Data from the

NATIONAL SURVEY OF FAMILY GROWTH

Patterns of Employment

Before and After Childbirth

United States

Statistics, based on data collected in 1973, are presented on the

employment of women before marriage, between marriage and first

birth, and between first and second births. Trends in employment

in these life-cycle stages are examined by comparing the experience

of women married in different periods. Employment of women

during and after the pregnancy preceding the most recent live birth

is also examined. These statistics on employment are shown for all

ever-marz-ied women, and for various socioeconomic groups.

DHEW Publication No. (PHS) 80-1980

Series 23

Number 4

U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE

Public Health Service

Office of Health Research, Statisticsr and Technology

National Center for Health Statistics

Hyattsville, Md. January 1980
Library of Congress Cataloging in Publication Data

United States. National Center for Health Statistics.

Patterns of employment before and after childbirth.

(Vital and health statistics : Series 23, Data from the National Survey of Family Growth ;

no. 4) (DHEW publication ; no. (PHS) 80-1 980)

Prepared by Larry L. Bumpass and James A. Sweet.

Bibliography: p. 14.

1. Mothers–Employment–United States. 2. Wives–Employment–United States.

3. Women–Employment–United States. I. Bumpass, Larry L. II. Sweet, James A. III.

Title. IV. Series: United States. National Center for Health Statistics. Vital and health

statistics : Series 23, Data from the Nation~ Survey of Fami]y Growth ; no. 4. V. Series:

United States. Dept. of Health, Education, and Welfare. DHEW publication ; no. (PHS)

80-1980.

HD6055.U53 1979331.4 79-607103

ISBN 0-8406 -0167-0

I:or sale by the Supcrintcndcllt of I>ocunlents, L“.5. (lo\7.rl]u]cl)t Printitlg OflIcr

\i”:l+illgtlm, 1). (.. ?O!(l:
NATIONAL CENTER FOR HEALTH STATISTICS

DOROTHY P. RICE, Director

ROBERT A. ISRAEL, Deputy Director

JACOB J. FELDMAN, Ph.D., Associate Directorfor/inalysis

GAIL F. FISHER, Ph.D., Associate Director for the Cooperative Health Statistics System

ROBERT A. ISRAEL, Acting Associate Director for Data Systems

ROBERT M. THORNER, SC.D., Acting Associate Director for International Statistics

ROBERT C. HUBER, Associate Director for Management

MONROE G. SIRKEN, Ph.D., Associate Director for Mathematical S tatistics

PETER L. HURLEY, Associate Directorfor Operations

JAMES M. ROBEY, Ph.D., Associate Director for Program Development

PAUL E. LEAVERTON, ph.D., Associate Director for Research

ALICE HAYW(OOD, Information Officer

DIVISION OF VITAL STATISTICS

JOHN E. PATTERSON, Director

ALICE M. HETZEL, Deputy Director

WILLIAM F. PRATT, Ph. D., chief Family Growth Survey Branch

MABEL G. SMITH, ChieJ Statistical Resources ~ranch

RITA U. HOFFMAN, chief ProNamming Branch

Vital and Health Statistics-Series 23-No. 4

DHEW Publication No. (PHS) 80-1980

Library of Congress Catalog Card Number 79-607103
FOREWORD

The National Survey of Family Growth collects information on the fertiIity,

family planning practices, and reproductive health of women in the United States.

The information is based on standardized, home interviews with large, nationally

representative samples of women in the reproductive years.

To supplement its own analyses of the Survey’s rich data, the National Center

for Health Statistics called upon various specialists outside the Center to prepare

several analytical reports in this series of Vital and Health Statistics.

This report was planned by its authors, Dr. Larry Bumpass and Dr. James A.

Sweet of the University of Wisconsin, within a generaI framework of analysis

requested by the National Center for Health Statistics. Dr. Bumpass and Dr. Sweet

conducted the analysis and prepared a report to the Center on their findings.

The report was adapted by Center staff for publication in Vital and Health

Statistics.

William F. Pratt, Chief

Family Growth Survey Branch

Division of Vital Statistics

...

III
CONTENTS

Foreword ...............................................................................................................................................

Introduction ...........................................................................................................................................

Source of Data ............................................................. ..........................................................................

Smmnary of Principal Findings .. ...........................................................................................................

Trends and Dlffcrcmtials in Female Employment at Pm-dcukwLife-cycle Stages ....................................

Premarital Employment ......... ..................................... ....................................................................

Employment Between Marriage and Childbfi ............. ................. .................................................

Employment Between First and Second Btis ............... .................................................................

Employment Within 2 Years of the Final Birth Intended ................. ................................................

Levels and Differentials in the Probabfity of Employment During Pregnancy

Duration of Employment in pregnancy

.............................. ........

................................................ . ..........................................

Work Since Latest Birth ....................................................................................................................

Proportion Entering the Work Force After Childbirth by Tning of Entry .......................................

References ........................................................................................................................ .....................

List of Detailed Tables ......... .................................................................................................................

Amxndixes .-

1.

2.

3.

4.

L Technical Notes ......................... ............................................................................... ...............

IL Definition of Terms ...................................................................................................................

III. Items on Questionnaire Relating to Employrncnt of Mothers in Intervals Before, Between, and

After Births ................................... ................. ..................... ..................................................

LIST OF TEXT FIGURES

Percent of ever-married women 1544 years of age who worked before marriage, percent of evcrmarried women 1544 ycam of age with a birth or intention to have a bti who worked between marriage and fit bti, and pcxent of ever-married women 15-44 years of agc with 2

births or a bii and intention to have a second who worked between firstand second btis,

by year of tit marriage: United States, 1973 .... ..... .................... .................... .......................

Percent of ever-married women 15-44 years of age, with work before marriage, who worked 2

years or more before maniagc; pcrccmt of ever-married women 15-44 ycam of age, with a bii

or intention to have a bti, and with work between marriage and first birth, who worked 1

year or more between marriage and fit bii; and percent of ever-married women 15-44 years

of age, with 2 bh-ths or a bti and intention to have a second, and with work between first

and second births, who worked 1 year or more between first and second biis; by year of

ilrst marriage: United States, 1973 .............. ................................................... ......"" ............ ...

Percent of cvcrmanied women 1544 years of age with 1 or more cbildrcn ever born who worked

during the last(most recent) pregnancy in 1970-73, and percent of ever-married women 15-44

years of age with 1 or more children ever born and employed during the last (most recent)

pregnancy who worked during the last trimester of that pregnancy, by paxity: United States,

1973 ........ ................................................................................................... ...............................

Pcment of ever-married women 1544 years of age with 1 or more chilcbxm ever born cmpIoycd

during the last (most recent) pregnancy in 1970-73 who returned to work since the last bti,

by parity: United States, 1973 ...................................................................................................

...

m

1

1

2

4

5

5

6

7

1;

10

12

14

15

34

44

49

2

3

3

4

v
SYMBOLS

Data not available-—-----–------—--- ---

Category not applicable——--—————— . . .

Quantity zero —---—-.-—- -

Quantity more than Obut less than 0.05——— 0.0

Figure does not meet standards of

reliability or precision—- *
PATTERNS OF EMPLOYMENT

BEFOR_EAND AITER CHILDBIRTH

Larry L. Bumpass, Ph.D., and James A. Sweet, Ph.D.,

Center for Demography and Ecology, University of Wisconsin, Madison

INTRODUCTION

The idea of a Iife cycle is an important

organizing principIe of social science research.

This concept recognizes that individuals live

their lives in a series of typically ordered stages,

and that there are crucial transition points that

involve decisions affecting subsequent stages.

Although various spheres of life such as marriage,

childbearing, and labor-force activity can be

studied individually, the life-cycle perspective

suggests that a better understanding of each of

these spheres of life can be achieved if they are

studied in relation to one another.

An important aspect of the Iife cycles of

women involves reproductive careers and laborforce activity. Throughout much of American

history, labor-force activity was concentrated in

one stage of the life cycle, and marriage and

reproduction in another. Only a small minority

of women were simultaneously workers, wives,

and mothers: a few very highly educated

women, women whose husbands were unable to

earn enough to support their families, and

women who were widowed, divorced, or

sepmated.

In recent years this segregation of activities

in the lives of women has diminished. As we

enter the 4th quarter of the 20th century,

nearly one-half of American women are in the

labor force. Among married women with children under the age of 3 in the household, about

one-third of the mothers are employed. Nevertheless, the probability of employment continues

to be influenced by the presence of young children in the household, by the composition of

families, and by other social and economic

factors.

This report describes and analyzes the

pattern of employment of American women in

relation to childbirth. It consists of three main

subject areas:

1.

2.

3.

Trends and differentials in female employment at particular life-cycle stages

Patterns of employment during pregnancy

Patterns of employment following childbirth

SOURCE OF DATA

The statistics in this report are from Cycle I

of the National Survey” of Family G;owth

(NSFG) conducted by the National Center for

Health Statistics (NCHS). The NSFG was designed to provide information about fertility,

family planning, and those aspects of maternal

and child health that are closely related to

childbearing. Data on these topics were collected by personal interviews with 9,797 women

aged 15 through 44 years who had ever been

married or who, although single, had offspring

living in the household. The interviews were

conducted between July 1973 and February

1974, and centered on September 13, 1973.

Respondents were selected by a multistage,

area probability, cross-sectional sample of

households in the conterminous United States.
Various subsets of this sample are used in different parts of this report; they are described

in conjunction with the analyses in which they

are used. Appendix I contains more discussion

of the sample design and discussions of estimating procedures and limitations of the data.

Appendix II contains definitions of terms used

in the report.

Two series of questions from the interview

are used extensively in this report. The first

determined how long a woman had worked

before marriage and in the intervals between

marriage and first birth, first and second births,

and second and third births. The second series

of questions asked how Iong before her most

recent birth the woman stopped working and

when she began work following that birth.

These questions are reproduced in appendix

III to this report.

SUMMARY OF PRINCIPAL

FINDINGS

Women are more likely to have worked

before marriage than at any other life-cycle

stage, less likely to have worked between marriage and first birth, and least likely to have

worked between the first and second births.

At all three of these life-cycle stages, however,

the percent of women employed has increased

over time. For instance, comparing women

first married in 1955-59 to women first married

in 1965-69, the percent who worked before

marriage increased from 80 to 84, the percent

who worked between marriage and first birth

increased from 66 to 80., and the percent who

worked between first and second births increased from 37 to 51 (see figure 1).

Many women worked before their last

child was 2 years old. Among mothers whose

most recent birth occurred in 1960-64, and who

intended to have no more children, 27 percent

worked before the latest child’s second birthday; the comparable statistic for women whose

latest birth occurred 2-3 years before the interview (in 1973) was 41 percent, a significant

increase.

Some of the increase in work activity by

women before marriage and between births of

first and, second babies may have been tempo102

[ m Year of first marriage1955.59

I

m Year of first marrmge 1965.691

80

60

40

20

0

Worked before rnarnage Worked beween marriage Worked Mween first

and first binh and second births

1196$-57 only f,), w{>,.,,, ‘A, 2 hlr[hs or . hir!l, ti!ldi!ltc!lllo!) 10lhWC m SCL’WIL

Figure 1. Percent of ever-married women 15-44 years of age

who worked before marriage, percent of ever-married

women 1544 years of age with a birth or intention to have

a birth who worked between marriage and first birth, and

percent of ever-married women 1544 years of age with 2

births or a birth and intention to have a second who

worked between first and second births, by year of first

marriage: United States, 1973.

rary or intermittent work, because the increasing trends are not observed always when shortterrn employment is excluded: The percent of

workers employed for 2 or more years before

marriage declined from 65 percent among

women first married in 1955-59 to 61 percent

among women first married in 1965-69, and the

percent of workers employed for 1 year or more

between first and second births did not change

significantly in the same period (see figure 2).

Not only do many women work between

births, many work during their pregnancies.

2
lW

[

m Yearoffimmarrla,e19s5.59

w Year of f,rst marria~ 1965.691

80

t

60 -

$

&

u

Y

40 -

20 -

0 -

..

65

Wbrked 2 ye,= or more Worked 1 year or more Worked 1 year or more

before mamagc tetwecn marrrage and between frost ●nd

fmf bmrh second b$rrh%

1196567 @ for W.!WII wth 2 h?r!hs., a hmh and mlenlmn w haw a ww.d

Figure 2. Percent of ever-merried women 1544 vears of eae. -.

with work before marriaga, who workad 2 years or more

before merriage; parcent of ever-married women 1544

yaars of age, with a birth or intention to have a birth, and

with work between marriage and first birth, who workad 1

year or more between marriaga and first birth; and percant

of evar-marriad women 1544 years of age, with 2 births or

a birth and intention to hava a second, and with work

between first and second births, who workad 1 year or

more batween first and second births; by year of first

marriaga: Unitad States, 1973

About 42 percent of ever-mamied mothers

worked during their most recent pregnancies;

and of those who worked during those pregnancies, about one-half worked in the last 3

months of the pregnancy. An earlier study

of women who had legitimate births in 1963

found that 31 percent worked duning pregnancy

then. 1 Working during pregnancy is more common among well-educated women than among

other women, more common among black

than white women, and more common among

women with few chiklren than among women

with many children (figure 3).

Among mothers whose latest birth occurred

in 1970-73, and who worked during that pregnancy, most (62 percent) had returned to work

by the time of the interview. The percents

returning to work were not very different for

women of different educational Ievels, and there

is no consistent trend with increasing education;

however, black women are more likely than

white women to return to work, and there is

some tendency for the percent returning to

102

60

60

+

z

g

!$

40

20

0

In

m

61

1

Worked during the last [most remm]

oregnancy m 1970.73

Worked d.rmg the last trtrmsler of

the last [most recent] pregmm.y m 1970.73

i-%

12 3 40, 123 4 or

more more

PARITY PARITY

—

Figure 3. Percent of ever-married women 1544 years of age

with 1 or more children aver born who workad during the

last (most recent) pregnancy in 1970-73, and percent of

ever-married women 1544 years of age with 1 or more

children ever born and employed during the lest (most recent) pregnancy who workad during tha last trimester

of that pregnancy, by parity: Un itad States, 1973

3
1s0—

so —

60 —

~

:

%

40 —

20 –

o .

65 64

1 2 3 4 or more

PARITY

Figure 4. Percent of ever-married women 1544 years of age

with 1 or more children ever born employed during the

last (most recent) pregnancy in 1970-73 who returned to

work since the last birth, by parity: United States, 1973

work to increase with the number of children

born (figure 4). Thus women with several

children are less likely to work during pregnancy,

but if they do work during pregnancy they are

more likely than other women are to return to

work after the birth.

The following sections contain a more detailed discussion of these and other findings

of the study.

TRENDS AND DIFFERENTIALS

IN FEMALE EMPLOYMENT AT

PARTICULAR LIFE-CYCLE STAGES

The decade of the 1960’s witnessed a large

increase in the employment of women, especially among mothers of young children. This

section examines that trend in terms of lifecycle stages. (For a related study of a State

population see Mott.2 ) For groups of women

married in successive 5-year periods beginning

in 1955 (“marriage cohorts”), trends and differentials in employment and length of employment are documented for the life-cycle stages

before marriage, between marriage and first

birth, and between first and second births.

Because interwds between births (“birth intervals”) tend to be short, much of the secondinterval employment (between first and second

births) is employment of mothers of young

children. However, employment of such women

‘is examined more directly in terms of trends in

the proportion who worked within 2 years of

the birth of their last (most recent) child.

Marriage cohorts before 1955 are not included because they are selective of young

ages of marriage, given the upper age limit of the

sample; for instance, women 44 years of age in

1973 who were married in 1952 were necessarily

married before the age of 24. In other words,

the sample women who married before 1955

underrepresent women who married at relatively

old ages, because some women were past the

upper age limit for sample eligibility (45 years)

at the time of the interview. In fact, even the

1955-59 sample cohort is somewhat biased

toward younger marriage ages.

Since marriage age is related to employment experience (early-marrying women tend

to work less at every life-cycle stage), this bias

could affect the interpretation of differences

between employment in the 1955-1959 marriage

cohort and subsequent cohorts. However, because the age-at-marriage bias in the 1.955-59

cohort is not large, its effect on comparisons

is probably not great. Even if all of tbe older

brides omitted from the sample (perhaps 5 percent of the 1955-59 marriage cohort) were in a

single employment category (an unlikely circumstance) the percents reported here would change

very little.

A similar problem exists with respect to lastintended births: Cohorts of last-intended births

are considered only after 1960 because earlier

cohorts must have completed childbearing before age 31, and thus are selective of those who

married young, Strategies employed to deal with

this problem (known technically as the problem

of “truncated open intervals”) are explained in

appendix I.

4
Premarital Employment

Proportion employ ed.–l’he proportion of

women who worked before maniage was Iarger

in the 1970-73 marriage cohort than in the

1955-59 cohort. The increase is observed in

most subgroups shown in tabIe 1, although not

all of the increases are statistically significant.

For two groups-those who married before

age 18 and those who had a premarital birth—

there was no increase between the 1955-59 and

1970-73 cohorts. The lowest employment rates

are found for women marrying before age 18

and” for women who did not complete high

school. The two are probably related: Early

marriage is a common reason for leaving high

school.

Employment for 2 or more years. –Among

women who worked before marriage, the proportion who worked at least 2 years was not

significantly different in the 1955-59 and

1970-73 cohorts, but there were significant

changes in some subgroups (see table 2). Women

who married at later ages and women with at

least some college education experienced increases in this proportion, although the latter

difference is not statistically significant. On the

other hand, decreases were experienced by black

women, women who married young and women

in low-education groups, although the latter

difference is not statistically significant.

The proportion working at least 2 years

before marriage varies directly with age at

marriage. This would be expected, because those

who marry later have more opportunity to work.

Education differentials are less clear, however.

A consistently linear, positive differential by

education is found only for the latest marriage

cohort.

Employment Between Marriage and

Childbirth”

Proportion employed. –Although increases

in early marital employment were registered

aWomen with a premarital pregnancy are excluded

from this analysis. Also the 1970-73marriage cohort is

not included because so many of its members had not

had a first birth to end the interval; see appendix I for a

full explanation.

among all groups considered, there were especially marked increases among black women

and women with little or no work experience

prior to marriage (table 3). Among black women,

the proportion working in the first interval

(between marriage and childbirth) increased

from 51 to 73 percent, and among women who

had either not worked or worked less than a

ye= before marriage, the increase was from 41

to 66 percent working between marriage and

childbirth.

Increases in the average lengths of first

intervals through postponement of fiist births

increased opportunity for employment in this

interval. However, at leaat at the aggregate

level, intercohort increases in employment are

not explained entirely by increases in the

length of first-birth intervals, since they occurred

among women of alI interval lengths. On the

other hand, the subgroup differentials in the

rate of increase in employment could reflect

subgroup differences in the lengthening of

first intervals over this time period.

Differentials in first-interval employment

are probably related to differences in the amount

of time available to work as conditioned by the

length of the first interval. Women who married

at young ages (less than 18 years) or who did

not fiiish high schooI are Iess likely than women

who married later or finished high school to

work between marriage and their first birth. In

spite of the increases experienced over the

decade, in the most recent marriage cohort only

about one-half of these groups worked in the

first interval, in contrast to over four-fifths

of the other age-at-maniage or education groups

combined. It is important to note in this regard

that although women with reported premarital

pregnancies or births have been excluded, it is

possible that the reporting error with respect to

premarital pregnancies is most serious for these

groups; that is, the low proportions working

may reflect the influence of premarital pregnancies not identified as such by the dating of

the pregnancy and marital histories.

Women who worked less than 1 year before

marriage were also less IikeIy to work after

marriage. However, the differential in firstinterval employment between those with less

than 1 year of premarital work experience and

those with 4 or more years of such experience

5
was reduced from 40 to 21 percentage points

between the earliest and latest marriage cohorts.

Employment of at least 1 year. –Unlike

trends in the proportion working in the first

interval, trends in the length of first-interwd

employment seem to be a consequence of the

changing opportunity to work resulting from

the increasing length of time between marriage

and childbirth (table 4). Among women with

similar interval lengths there is no significant

increase. Thus differential changes in employment of at least a year among other groups probably reflect differential increases in first-interval

lengths. For some subgroups, the increase in

proportions working at least a year between

marriage and birth of the first child are very

large; for instance, the proportion increased

from 56 to 80 percent among women marrying

at ages 22 and over, and from 61 to 81 percent

among women who attended college before

marriage. For the latest marriage cohort, there

was a direct relationship of extended firstinterval employment with education and age at

marriage, and no significant difference by race

or previous work experience.

Employment Between First and

Second Birthsb

Proportion employed. —Emplo yment between the births of first and second children

also increased among all groups considered

(table 5), significantly in almost all instances.

As for first-interval employment, this increase

is not simply a consequence of increasing

interval lengths since it is observed among

women with similar interval lengths. There

was an irregular pattern of changes among black

women, including an increase for the 1965-67

marriage cohort. Black women are more likely

than white women are to work between first and

second births (62 and 50 percent, respectively),

although more rapid increases among white

women have narrowed the gap. The rate of

increase in employment between first and second

bWomen married in 1968-73 are not included

because so many of them had not had a second birth

to end the interval; see appendix I for a full explanation.

births varied by education and previous work

experience. Whereas the rate for women with 12

or fewer years of education at marriage increased

16 percentage points (52 compared with 36

percent), there was a statistically insignificant

increase of only 4 percentage points among those

who had attended college before marriage. Also,

among women who had not worked at all,before

their first birth, the proportion working in the

second interval doubled from 22 percent in the

1955-59 cohort, to 43 percent in the 1965-67

cohort, compared with a modest increase from

44 to 52 percent among those who worked before the first birth. As a consequence of those

varied trends, differentials in the experience of

employment in the interval between first and

second births tended to be reduced for race,

previous work experience, and education.

The trends and differentials by age at marriage are particularly interesting. For all three

marriage cohorts, women who married at ages

22 and over are the least likely to be employed

in the interval between first and second births,

although the differences are not all statistically

significant. This might reflect the association

of older age at marriage with greater economic

security and hence less need to work. (However,

this interpretation is called into question by the

fact that the highest education group was

neither significantly less nor more likely to work

in any of the cohorts.) In any event, by the

1965-67’ marriage cohort, women who married

at ages 20 and over were 8 percentage points less

likely to work in the second interval than

women married at younger ages were.

Employment of at least 1 year–Whatever its

explanation, the decline over the last two marriage cohorts in the proportion of employed

women working at least a year between their

first and second births occurred for all groups

considered, although it was not always statistically significant (table 6). This proportion increased in most groups (not always significantly)

in the 1960-64 cohort, but then returned to the

earlier level for the 1965-67 marriage cohort,

declining from 70 to 62 percent. Although such

cl-ianges should be regarded cautiously, the most

Iikelv sort of bias does not appear responsible.

Tha~ is, rather than

lengths of exposure

being an ~~tifact o; shorter

among women in the most

6
recent cohort, as a consequence of remaining

truncation (see the discussion in appendix I),

the decline is greater among those with intervals

3 years or more in length than among women

with shorter intervals. If other sources corroborate this finding, it is important in its implication for the interpretation of recent increases in

the employment of mothers of young children.

The new entrants may be seeking such employment on a more short-term basis than employed

women with young children have in the past, or

they may be entering more tentatively and withdrawing from employment upon discovering the

difficulties involved.

Employment Within 2 Years of

the Final Birth Intended

One of the most remarkable changes in the

labor-force participation of women has been

the increase in the employment of mothers of

young children. As noted, the preceding section

relates indirectly to that issue. The 1973 NSFG

data provide further information on the basis

of reports about how soon the respondent went

back to work after her most recent child. Because the information is available only for the

most recent birth, some strategy must be employed to maximize the comparability of the

data over time. In order to examine trends in

the proportion of mothers working when the

child is less than 2 years old, it is necessary to

count only those births that occurred at least

2 years before interview. In order to avoid a

bias in the intervals being compared, it is also

necessary to limit the analysis to women who

intend to have no more children. This is because

women who intend to have more children and

whose latest birth was at least 2 years ago are a

selected subset of women who gave birth in the

same year and would continue chddbearing;

that is, they are selected for longer birth intervals. For, the sake of brevity, the following

text will simply refer to employment of mothers

of young children; it should be kept in mind

that the measure- is, more specifically, of employment within 2 years of the birth of the

final child intended. Trends are measured here

over dates of birth of final-intended children

rather than over marriage cohorts as in the

previous sections.

The increase in the employment of mothers

of young children was pervasive (table 7). For

example, similar trends were experienced at

all education levels, and with some further

reduction in the modest differences by education. Women with only one or two children

were more likely than women with larger

families to work when the youngest child

was under 2, and this difference increased over

this period. In the early 1970’s, one-half of the

mothers of smalI families worked within 2 years

of the final-intended child’s birth compared with

one-third of the mothers of three or more

chiIdren.

B1ack women, who had the highest employment level initially, experienced greater increases than white women did, further widening

the difference by race. For final-intended

births in the early 1970’s, 62 percent of the

bIack mothers worked within 2 years compared

with 38 percent of the white mothers. This

increasing differential occurred despite considerable increases among white women.

The differences by age at marriage paralleled

those noted for second-interval employment.

Women who married at 22 years of age or after

were less likely to work soon after the birth of

their last child than were women who married

before age 18. Again, if this reflects lower

financial need among those who marry later,

such an effect is not reflected in the education

differential.

LEVELS AND DIFFERENTIALS IN

THE PROBABILITY OF EMPLOYMENT DURING PREGNANCY

In this section, levels and differentials in

the proportion of women who work during

pregnancy are examined. Data are presented on

the proportion employed at any time during

pregnancy and the proportion employed during

the last trimester of pregnancy. The latter measure is based on the subsample of women who

were employed during pregnancy.

As noted in the previous section, the sample

of latest births is not a good sample of the

$B 7
. .

experience of women giving birth in any given

period of time, with the possible exception of

the most recent 9- to 12-month period. This is

because a large fraction of women who gave

birth in a particular period, for example,

1965-69, have since given birth to another

child, now their most recent birth, so their

earlier births are not included in the births for

1965-69. The sample of most recent births is

less representative of all births in a period the

further the analysis moves back in time. In

addition, women have aged out of the sampling

universe. For example, women giving birth to

their latest child in 1968 who were then over

the age of 40 are not included in the sample that

was under age 45 as of 1973. This analysis is

focused on births occurring in the period 1970-73

in the attempt to use the experience of the

sample that most completely represents the

total experience of all women giving birth

during a particular time period.

An additional consideration in this regard

is that aggregate employment rates of women

have been increasing for the past several decades

by 0,5-1.0 percent per year. The total sample of

“most recent births” spans a very broad period

of time. Consequently, the experience of older

women, whose latest birth occurred in the more

distant past, occurred in a period when employment rates for women were lower.

Analyses were done for the total sample of

most recent births and for those most recent

births that occurred during the period 1970-73.

For the reasons specified, this discussion is

limited to the 1970-73 births, although the

results for all most recent births are included

in the detailed tables.

Throughout this section, the statistical

procedure employed is “Multiple Classification Analysis. ~s8 This ca be thought of as a

multiple standardization in which composition

of the population with respect to selected variables is statistically controlled while assessing

the “effect” on the rate of employment of a

particular variable of interest. In tables 8 and 9

the column labeled “Percent” shows the proportion of women in each category who reported a given behavior; the column labeled

“Adjusted percent” is the standardized proportion, adjusted for the association of each characteristic with other characteristics included in

the analysis. Following table 10, which shows

only unadjusted percents, tables 11-12 also show

percent and adjusted percent columns, as just

defined.

For analyzing the interrelationships of

several characteristics simultaneously, Multiple

Classification Analysis has certain advantages

over cross-tabulation. In cross-tabulation the

simultaneous interrelationships of several characteristics are analyzed by cross-classifying cases

according to their category values on each of

the severaI characteristics; when this is done

with relatively small samples, however, the number of cases in individual cross-classified categories is often too small to produce reliable

statistics. In Multiple Classification Analysis

the data are handled differently, and simultaneous analysis of many variables need. not

reduce reliability. It is possible, therefore, to

consider more different characteristics, and to

consider more-detailed categories in each ch~aracteristic. That possibility is exploited in this and

the following sections of this report; many

characteristics are considered simultanecmsly

and some have many separate categories. Some

characteristics that appeared earlier are defined

somewhat differently in the following sections

to take advantage of the opportunity for more

detailed analyses afforded by Multiple Classification Amdysis. Additional discussion of Multiple

Classification Analysis is contained in appendix I.

OveraU, 42 percent of women giving birth

in 1970-73 worked at some time during their

pregnancy. (This compares with 38 percent

of the entire sample.) This proportion varied

quite widely depending on the order of the

birth (see table 8). For women giving birth to

a first child, 61 percent worked; for women

giving birth to a second child, 36 percent

worked. For third and higher order births, the

mothers had an employment rate. during pregnancy of 28 percent. Thus the major difference

occurred between women who gave birth to a

first child and those who had a higher order

birth. This is probably because women having

their first child did not have preschool-age

children of their own in the household during

the time that they were pregnant; but those

giving birth to a second or higher order child
often had preschool-age children in the household. If adjustments are made for the other

factors, the differential in employment during

pregnancy by parity increases slightly.

In Multiple Classification AnaIysis, two

variables with a common category cannot be

analyzed simultaneously. Because they have a

common category (no previous births), it was

not possible to include in the same model both

the parity of women and the time since previous

birth, that is, the interval between the birth

in question and the previous birth. This latter

variable was adjusted separately by including

all of the variables in table 8 except parity.

The proportion employed during pregnancy

increases with the length of the interval, which

is equivalent to the age of the youngest child

at the time of pregnancy: Women who had a

birth interval of 6 years or more had an unadjusted rate of employment of 46 percent,

compared with a rate of 26 percent for those

with an interval of less than 2 years. These differentials’ are not affected when other factors are

controlled. This finding results primarily from

the fact that the rate of current employment

vties directly with the age of the youngest

child. Women with a very young child tend to

have quite low rates of employment. The longer

the interval between births, the older the youngest child, the more likely the woman is to be

employed. Related to this may be the tendency

for women with longer interwds between children to expect no more children, and to begin

working as a result of that expectation.

By age, the highest unadjusted rate of employment during pregnancy occurs for women

who were 20-24 years of age at the time of the

birth, 50 percent. However, when other factors

are adjusted, the pattern changes. Women who

were under age 20 at the time of the birth had

an adjusted rate of 24 percent; women aged 20-

34 years had rates of 43-47 percent, and women

aged 35 and over (only a small proportion of

women in the sample) had a rate of 39 percent.

The low rate of employment for women under

age 20 reflects both their lack of work experience prior to the birth and the disadvantage

very young women experience in the labor

market.4 The reduction in the adjusted rate

for women aged 20-24 reflects the fact that

births to women of this age are very often

first births; it was noted previously that employment rates are high in the pregnancy preceding the first birth.

Women with higher levels of education were

more likely to work during pregnancy than

women were with less education. Women with

less than 12 years of education had an employment rate of less than 35 percent; women with

13 or more years of education had rates of

48-50 percent. These differentials are attenuated,

however, when the effects of other factors,

particubrly birth order and age, are controlled.

The adjusted rate for college graduates is low

(34 percent).

Black women had a rate of employment of

about 50 percent, compared with a rate for

white women of 42 percent. Hispanic women

had a rate of employment of 37 percent. After

controlling for other factors, the rate for Hispanic

women is intermediate between that for white

and black women, but closer to the rate of black

women.

There were modest regionzd differences in

employment during pregnancy. The adjusted

employment rate of women in the West is lower

than average and that for women in the South is

higher, although the latter difference is not

statistically significant. There is also a slight

difference between the rate of employment of

women living in metropolitan areas and those

living outside of metropolitan areas, although it

is not statistically significant. After adjusting

for other factors, women J.iving outside metropolitan areas have a rate that is about 3 percentage points higher than that for women living in

metropolitan areas.

Rates of working during pregnancy are also

considered for women classified by their current

or most recent occupation. This procedure for

classifying women by occupation is not completely adequate. Because occupation is not a

fixed characteristic, women may reenter the

labor force in an occupation group different

from that they left; indeed, the probability of

working at any given point may be related to

whether a woman’s previous job was commensurate with her training and skib. Similarly, a

woman whose family has great economic need

may be more willing to work in an occupation

9
below her qualifications than a woman who is

more affluent. Higher than average adjusted

rates of employment during pregnancy are

found for women who are professionals (59 percent), managers (57 percent), and operatives and

transport workers (48 percent). The rates of

women in other occupational groups do not

differ significantly from the average.

Finally, the year of most recent birth was

included as a control variable in the analysis.

This variable does not represent adequately the

time trend in working during pregnant y, because

the sample of most recent births that occurred

in a given period is not a sample of the total

universe of births in that period, as explained

earlier. For instance, the sample of births in

1970 is not representative of all births during

1970, because women who had a birth in 1970

and also in a later year would be classified in

the year of the most recent birth; therefore,

these differentials are not easily interpreted.

Duration of Employment in

Pregnancy

For women employed during pregnancy, the

proportion employed during the last trimester

of pregnancy is shown in table 9. In the sample

of women who gave birth to their latest child

in 1970-73, 48 percent of those who worked

during their pregnancy worked in the last trimester. The figure for the entire sample of

women is somewhat lower, 45 percent. Some

differences in this measure among subgroups of

women whose latest birth occurred in 1970-73,

adjusted for the effects of other variables, are

discussed briefly:

1. Low-parity women (parity 1) are more

likely than high-parity women (parity 4

or higher) to work into the last trimester of pregnancy.

2. Women 30 years old and over who gave

birth are more likely than younger

women, other things being equal, to work

into the last trimester.

3. Women living in metropolitan areas and

in nonmetropolitan areas are equally

like~lyto work into the last trimester.

4.

5.

6.

Regional differences are small and nonsignificant with regard to this measure of

work patterns.

Education does not have a linear relationship to working during the last trimester:

High school graduates have the highest

proportion, and women with less or

more schooling have lower rates.

There are no significant racial and ethnic

differences in $e probability of working

into the last trimester.

The timing of departure from the labor force

during pregnancy is also described by the proportion still employed at each month of pregnancy. Included in this analysis were women

who gave birth in the 2 years before the interview, and who worked at some time cluring

their most recent pregnancy. Table 10 indicates

the cumulative proportion remaining in the

work force at each month of pregnancy. For example, in the total column it will be seen that

by the 2d month of pregnancy, 7 percent of

those who were working at the beginning of

pregnancy had dropped out and 93 percent of

women remained at work. By the 6th month of

pregnancy, 61 percent remained. Beyond the

6th month, the proportion remaining drops off

rapidly. Less than half were working by the 7th

month, less than one-third by the 8th month,

and 19 percent by the 9th month. For the total

sample, the median point at which women leave

the work force is 6.9 months. Black women have

a median that is a half month earlier than that

of white women. Women who are high school

graduates, or who attended college remain in the

work force approximately 1 month longer than

those who did not finish high school. Women

having a first birth have a median of 7.2 months,

and women having a second or third and higher

order births have a median duration of 6.3-6.5

months.

Work Since Latest Birth

In this section, differentials are examined in

the probability that a woman who had her

most recent birth in the period 1970-73 had

worked since that birth. Forty-two percent of

the mothers who had a birth in that period

10
had worked since their latest birth. This proportion varies with the length of the intervals

since the most recent birth (table 11). Fifty-six

percent (adjusted) of women who had their

most recent birth in 1970 had worked by the

time of interview in 1973. This compares with

53 percent of those having a birth in 1971, 39

percent in 1972, and 14 percent in 1973.

These differentials reflect both the greater

opportunity for work associated with the

aging of the youngest child, and an increase in

the length of exposure to the possibility of

having worked.

Women whose most recent birth was a

first birth have considerably higher rates of

work since last birth, unadjusted and adjusted,

than those whose most recent birth was a second

or higher order birth. This is consistent with

earlier findings that there is a large difference in

employment rates between women with one and

two children, but only relatively small differences

between them and women with larger numbers

of children.

The rate for black women is quite high (56

percent), and that for white women is 40 percent. The rate for Hispanic women is not significantly different from that for white women

(42 percent) and is closer to the white women’s

rate than to the rate for black women. The

black-white differential is only slightly attenuated after controlling for other factors; however,

the rate for Hkpanic women is increased, so

that it is almost as high as that for black women.

There are only insignificant differences in

adjusted proportions employed with respect to

whether they expect additional children. It

seems reasonable that women might pkm their

work and childbearing so that those who have

had their last-intended child are more likely

to return to work than those who expect to have

an additional child. This, however, was not

found by Sweet4 using the 1965 National

Fertility Study, nor is it found here.

Women under age 25 at the time of a birth

were more likely than older women were to

work following the birth. This is true both

for the unadjusted and the adjusted rates.

Regional differences in employment are

significant, though not large. Women living in

the South and West have adjusted rates of

employment higher than those of women living

in the Northeast and North CentraI Regions.

Similarly, as was found for working during

pregnancy, women living outside of metropolitan areas have higher rates of employment than

do those living within metropolitan areas,

although those differences are not significant.

The association of higher education with

employment is once again found. The adjusted

rate of employment since latest birth for women

who are college graduates is 11 percentage

points higher than the rate for women who had

not attended high school.

Women who were no longer man-ied at the

time of interview in 1973 have high rates of

employment (57 percent, adjusted). Women

whose husbands are at either extreme of the

income distribution have lower than average

rates; those whose husbands are intermediate in

that distribution have rates that are not significantly different from average.

There are some sizeable differences in

employment by occupation. Women in clerical

occupations have a lower rate of employment

(36 percent, adjusted). Higher than average

rates are found for women in professional,

service, and operative occupations. Women in

other occupations have intermediate employment rates not significantly different from the

average in this survey.

One important issue is the extent to which

pregnancy disrupts periods of employment. It

is addressed by the following analyses of Ievels

and differentizds in returning to work following

childbirth. Because it is possible for a woman to

return to work after a birth only if she was

working prior to the birth, the sample is restricted to women who reported working during

their last pregnancy ending in live birth. Again,

the focus is on the experience of women who

gave birth to a child since January 1, 1970.

Although 42 percent of women giving birth

since 1970 had worked since their latest birth,

62 percent (adjusted) of those who were working during their pregnancy had returned to work

by the time of enumeration in 1973 (table 12).

The average interval from last birth to time of

observation was approximately 1?/2 years, but

some women in the sample had had only a few

days of opportunity to return to work; that is,

they had given birth just a few days before being

interviewed. Others had given birth a full 3 years

11
before. In this analysis, there is a statistical

control for year of birth to adjust for this

differential period of work reentry opportunity.

Women who gave birth in 1973, shortly before

being interviewed, have a much lower than

average unadjusted rate of return to work (28

percent); those who gave birth to their last

child in 1970 or 1971 have a high unadjusted

rate of return (74-77 percent). This reflects

both differences in the duration of opportunity

to return to work, and the probability that

many women who gave birth in 1970 and did

not go back to work were likely to have had a

subsequent pregnancy, and were thus selected

out of the sample of 1970 last births and into

the sample of more recent last births.

Fifty-nine percent of white women, compared with 73 percent of black women, had

returned to work since the birth of their latest

child. The Hispanic women had a rate of return

of 66 percent. When other factors are adjusted,

the rate for Hispanic women is not significantly

different from the rate for black women.

The unadjusted relationship between education and return to work is irregular. However,

when adjustment is made for husband’s income

and other characteristics, the relationship becomes positive. The adjusted proportion returningwas 46 percent of the women who did not

attend high school and 56 percent of women

with 1-3 years of high school, both significantly

lower than the 71 percent of college graduates

who returned.

Women who were under age 20 at the time

of the birth have a high adjusted rate of retuim

to work (79 percent). Women 20-24 to 30-34

years have rates of 59-63 percent.

Husband’s income is not significantly related to having returned to work, except that

women in the lowest income group are less

likely than average to return to work. Women

who were not currently married at the time of

interview had an adjusted rate 11 percentage

points above the average. The probability of

returning to work is lower after first births

than after higher order births, although the

difference is not statistically significant.

Among the occupationzd categories with

sufficient numbers of cases to permit analysis, the only significant difference is a lower

than average rate of return to work among

women whose most recent occupation was

clerical. Just over half (53 percent) of such

women had returned, compared with about

two-thirds to three-fourths among other occupations.

There are some significant regional differences in return to work. Women in the South

and West are more likely to return to work than

those in the North Central or Northeast. Women

living in metropolitan areas have significantly

lower rates of return to work than those living

outside of metropolitan areas.

Proportion Entering the Work

Force After Childbirth by

Timing of Entry

In this section the timing of entry into the

work force following childbirth is examined,

with the focus on the pattern of entry by

2-month intervals during the first year after

childbirth, using a subsample of women who

gave birth 12-23 months before interview.

Women who gave birth in the past 12 months

are excluded, because they had not had 12

months of opportunity to enter the labor

force. Sample women who gave birth more

than 2 years before interview are excluded

because they are not representative of women

who gave birth in those earlier periods.

It is emphasized that these rates are the

cumulative proportions of women who entered

the work force by a given month after pregnancy, not the proportion working in that

month. Many women who have returned to

work in, say the 6th month after birth, may not

be working in the 12th month after birth,

because there is a great deal of movement in

and out of the work force following the birth

of a child. In earlier studies it was shown that

about one-half of the women who gave birth

12-23 months before interview and who had

entered the work force since that birth, were

not working when interviewed.4’6

Five percent of women reported having

begun working in the first 2 months after the

birth of their child (table 13). This is a reasonable estimate of the proportion of women who

work almost continuously through the period

12
of childbirth with only a very short period out

of the labor force. By the 4th month after the

birth of a child, 15 percent of women have

entered the work force; by the 8th month the

figure is one-quarter; and by the 12th month,

31 percent of women have entered the work

force.

The remaining columns in table 13 present

cumulative proportions for women by race,

education, and birth order. Black women have

a more rapid rate of entry into the work force

following a birth: By the end of the 4th month,

20 percent of the black women, compared

with 14 percent of the white women, have

entered the work force; by the 8th month the

figures are 38 and 23 percent, respectively;

and by the end of the 12th month, 44 percent

of the black women and 30 percent of the

white women have entered the work force.

LeveIs of entry also vary by education.

Women who have attended college have lower

rates of entry into the work force after childbearing than other women have. High school

graduates and women with less than a high

school education have patterns of entry into

the work force that are similar to each other.

Generally, women who gave birth to a first

child have a higher cumulative rate of entry

into the work force than women who had

second or higher order births: By the 8th

month after childbirth, 31 percent of the

women who had a first birth had entered the

work force, compared with 19 percent of women

who had a second birth. Women who have had

a third or higher order birth have a higher

cumulative rate of employment than women

who had a second birth. A reason for the higher

employment rate of higher parity women may

be the greater economic need of large families.

Another way of looking at these same data

is to focus attention on the pattern of returning

to work for women who were working prior

to their pregnancy. This takes into account the

fact that some women remove themselves from

the labor force for the whole childbearing

period; other women work between births of

their children. Looked at from the perspective

of the work force, returning to work is more

relevant than the initial employment following childbirth. From an employer’s point of

view, for example, the probability that a woman

who becomes pregnant will stop working, and

the timing of her return, are more significant

than the probability that any woman having

given birth will enter the work force. Of the

women who were working during their pregnancy, 10 percent had returned to work by the

2d month following the birth of their child

(table 14). More than one-quarter had returned

by the 4th month, and more than one-third by

the 6th month. By the 12th month nearly onehalf had returned. For black women the rate of

return was considerably greater than that for

white women. By the 8th month, 56 percent

of the black women, compared with 40 percent

of the white women, had returned. By the

12th month, 60 percent of the black women,

compared with 48 percent of the white, had

returned. With respect to education, the highest

rate of return at any given interval since birth is

for women with less than a high school education, and the lowest cumulative proportion

returning is for college-educated women. The

level for women who are high school graduates

is intermediate.

Women who have a high-order birth have

high rates of returning to work; those who had a

first- and second-order birth have rates of

returning that are quite similar to one another.

Why sho~d the rate of returning be so much

higher for mothers of high-order births than for

mothers of Iower order births? First, mothers

of high-orde; births are more likely than others

to have an economic need motivating them to

seek employment.7 A second rem,on is that

women who had been working prior to a thirdorder or higher order birth may have adapted

their lifestyle to working. Such women probably have a higher than average commitment to

working.

000

13
REFERENCES

lNational Center for Health Statistics: Employment during pregnancy: Legitimate live births, United

States–1963. Vital and Health Statistics. PHS Pub. No.

1000-Series 22-No. 7. Public Health Service. Washington.

U.S. Government Printing Office, Sept. 1968.

2Mott, F. L.: Fertility, life cycle stage and female

labor force participation in Rhode Island: a retrospective overview. Demography 9:173-185, 1972.

3Andrews, F. M., Morgan, J. N., Sonquist, J. A., and

Klein, L.: Multiple Classification Analysis, 2nd ed. Arm

Arbor, Mich. Institute for Social Research, 1973.

4Sweet, J. A.: Women in the Labor Fovce. New

York. Seminar Press, 1973

5Sweet, J. A.: The Employment of Mothers of

Young Children: 1970. CDE Working Paper 74-17.

Madison. Center for Demography and Ecology, University of Wisconsin, 1974.

6Sweet, J. A.: Return to Work After Childbirth.

CDE Working Paper 74-16. Madison. Center for Demograph and Ecology, University of Wkconsin, 1974.

YRindfuss, R. R., and Sweet, J. A.: Postwar Fertility Trends and Differentials in the United States.

New York. Academic Press, 1977.

8National Center for Health Statistics: The National

Survey of Family Growth, Cycle I: sample design,

estimation procedures, and variance estimation. Vital

and Health Statistics. Series 2-No. 76. DHEW Pub. No.

(PHS) 78-1350. Washington. U.S. Government Printing

Office, Jan. 1978.

9U.S. Bureau of the Budget: Standavd Metropolitan Statistical Areas. Washington. U.S. Government

Printing Office, 1967.

1‘U.S. Bureau of the Census: 1970 Census of

Population, Detailed Characteristics, US. Summary.

PC( 1)Dl. Washington. U.S. Government Printing Office,

Feb. 1973. pp. A17-A18.
LIST OF DETAILED TABLES

1. Percent and number of women who worked before marriage, by year of first marria9e and sele=t~ characteristics: evermarried women 1544 years of age, United States, 1973 ...........................................................................................................

2. Percent and number of women who worked 2 years or more before marriage, by year of first marriage and selected characteristics: aver-married women 1544 yaars of age who worked before marriage, United States, 1973 ...................................

3. Percant and number of women who worked betwaen marriage and first birth, by yaar of first marriaga and selected characteristics: ever-married women 1544 years of age, United Statesr 1973 .................................................................................

4. Pemant and number of women who worked 1 year or mora between marriage and first birth, by year of first marriage and

selected characteristics: ever-married women 1544 years of age who worked between marriage and first birth, United

States, 1973 ............................................................................................................................................ ............................ ......

5. Percent and numbar of women who worked between first and second births, by year of first marriage and selected characteristics: ever-married women 1544 years of age: Unitad Stetas, 1973 ...............................................................................

6. PerCant and numbar of women who worked 1 year or more between the first and second births, by year of first marriage and

selected characteristics: ever-married woman 1544 yaars of age who worked between the first and second births, United

States, 1973 ...................................................................................................................................... ................................. .......

7. ParCent and number of women who worked within 2 years of their final birth, by year of final birth and selected characteristics: ever-married women 1544 years of age whose final bhth was at least 2 yaars ego, United States, 1973 ..........................

8. Percent, adjusted percent, and number of woman who worked during tha latest pregnancy, by selected characteristics,

according to year of latest birth: ever-married women 1544 yaars of age, United States, 1973 ...............................................

9. Percent, adjustad percent, and number of women who worked during the last trimester of the latest pregnancy, by selected

characteristics, according to year of latest birth: evar-married women 1544 years of age who worked during tha Iataat pregnancy, United States, 1973 .......................................................................................................................................................

10. Number of woman and percent amployed during aach month of the latest pregnancy, and median number of months employed during that pregnancy, by rata, aducation, and parity: aver-married women 1544 years of age who worked during

the latest pragnancy whose latest birth was less than 2 years ego, United Stetas, 1973 .............................................................

11. Percent, adjusted parcant, and number of women who worked since the latest birth, by selected characteristics, according to

year of Iatast birth: ever-married women 1544 years of age, United States, 1973 ...................................................................

12. Percent, adjusted percent, and number of women who returned ~o work since the latest birth, by selected characteristics,

according to year of latest birth: avar-rnarried women 1544 years of age who worked during the latest pregnancy, United

Statas, 1973 ............................................................................................................................................ ............................ ......

13. Number and cumulative percent of women who worked since the latest birth, by number of months since latest birth,

according to race, education, and parity: ever-married women 1544 years of age whose latest birth was 12-23 months ago,

United Statesr 1973 ............................................................................................................................................ ......................

14. Number and cumulative percent of women who returned to work after the latest birth, by months since latest birth, according to race, education, and parity: ever-married women 15-44 years of age who worked during the Iatast pregnancy, Unitad

States, 1973 ..............................................................................................................................................................................

16

17

18

19

20

21

22

23

25

27

28

30

32

32

15
Table 1. Percent and number of women who worked before marriage, by year of first marriage and selected characteristics: @Varmarriad women 11544 years of age, United States, 1973

Characteristic

All woman ................. ...................... ........................

-e

White .......................................................................................

Black .......................................................................................

Age at marriage

Lass than 18 yaars ...................................................................

18-19 years ..............................................................................

20-21 yaam ................................... ...........................................

22 yaars or more .....................................................................

Education at marriage

Less than 12 years .............................. .......... ...........................

12 years ...................................................................................

More than 12 years ..................................................................

Timing of first birth

Bafora marriage ..................................................... ......... .........

After marriage ........................ ................................... ..............

1Includes only women fiist married 195S-’?3

Parcent

so

87

76

52

88

94

95

67

91

94

77

87

84

85

73

49

83

91

96

63

E

75

84

Year of first marriage

79

81

71

44

83

90

93

61

87

88

68

80

1955-

1959

80

B2

68

55

82

90

91

63

89

91

77

80

EEEIEEIE

Numbar in thousands

4,703

4,218

405

429

1,514

1,239

1,526

898

2,276

1,531

308

4,410

6,080

5,439

550

550

1,794

1,669

2,035

1,170

3,034

1,836

423

5,606

4,543

4,152

401

515

1,525

1,196

1,315

1,0s1

2,400

1,074

261

4,283

4,192

3,781

377

639

1,306

1,060

1,1s8

1,150

2,172

8s5

249

3934

.—

NOTE: Numbers may not add to totals because of rounding; see appendm I.

16
Table 2. Parcant and numbar of women who worked 2 years or more bafora marriage, by year of first marriage and selectad

characteristics: ever-marriad women 11544 years of aga who worked bafore marriage, United States, 1973

Characteristic

All women ................................... ............................

Rata

White .......................................................................................

Black ................................................................... ....................

Age at marriage

Less than 18 years .... ...............................................................

18-19 years ............ .......................................................... ........

20-21 years ............................... ...............................................

22 years or mora ......................................... ............................

Education at marriage

Less than 12 years .......... ............................................ .............

12 years ..................................................... ..............................

More than 12 years ..................................................................

Timing of first birth

Before merri~ ..................................................... W ..............

After marriage ........................................................ .... .............

lInclude~ only women fiist married 1955-73.

Year of first marriage

1970-

1

1965- 1960-

1973 1969 1964

61

62

51

25

39

68

87

43

62

69

60

61

Percent

61

61

59

34

43

63

81

50

67

57

59

61

62

62

63

33

44

70

86

60

65

56

65

61

1955-

1959

65

65

71

34

54

80

81

62

68

61

67

65

EIIzEIE

Number in thousands

2,867

2,613

208

107

587

843

1,330

386

1,406

1,060

185

2,679

3,689

3,316

325

186

776

1,051

1,643

590

2,031

1,048

251

3,431

2,820

2,546

253

170

673

834

1,128

643

1,561

602

171

2,614

2,725

2,441

268

216

707

644

965

709

1,470

540

167

2,563

NOTE: Numbers may not add to totals because of rounding; see appendix I.

17
Table 3. Percent and number of women who worked between marriage and first birth, by year of first marriage and selected characteristics: ever-married women 1 15-44 years of age, United States, 1973

Characteristic

All women ...........................................................................................

~

White ...................................................................................................................

Black ....................................................................................................................

Age at marriage

Less than 18 years ................................................................................................

18-19 years ..........................................................................................................

20-21 years ..........................................................................................................

22 years or more ..................................................................................................

Education at marriage

Less than 12 years ................................................................................................

12 years .................u.............................................................................................

More than 12 years ..............................................................................................

Premarital employment

None or less than 1 year .......................................................................................

1-3 years ..............................................................................................................

4 years or more ....................................................................................................

Interval between marriage and first birth

Less than 1 year ...................................................................................................

1-2 years ..............................................................................................................

2 years or more ....................................................................................................

Year of first marriage

1965- 1

1960- 1955-

1969 1964 1959

80

81

73

50

77

90

88

52

85

91

66

87

87

59

71

93

Percent

69

70

63

45

69

78

78

45

75

83

52

77

80

52

64

85

66

67

51

42

65

76

75

44

75

76

41

76

81

56

60

82

1965- 1

1960-‘1955-

1969 1964 1958

Number in thousanda

4,311

4,058

222

362

1,227

1,302

1,429

564

2,253

1,505

1,127

1,944

1,259

576

1,125

2,630

2,991

2,840

151

375

944

813

852

517

1,597

877

775

1,344

558

991

1,456

2,699

2,554

114

339

834

739

771

547

1,496

647

547

1,268

880

670

934

1/096

I Includes OS-II~ women who have had a birth (or intend a birth), were first married 1955-69, and had no premarital PregnancY.

NOTE: Numbers may not add to totals because of rounding; see appendix L

18
Table 4. Percent and number of women who worked 1 year or more between marriage and first birth, by year of first marriage and

selacted characteristics: ever-married womenl 1544 years of age who worked between marriage and first birth, United States, 1973

Characteristic

All women ...........................................................................................

Race

White ...................................................................................................................

Black ....................................................................................................................

Age at marriage

Less than 18 yaars ................................................................................................

18-19 years ..........................................................................................................

20-21 years ..........................................................................................................

22 years or more ..................................................................................................

Education at marriage

Lass than 12 years ................................................................................................

12 years ...............................................................................................................

More than 12 years ..............................................................................................

Premarital employment

None or less than 1 year .......................................................................................

1-3 years ..............................................................................................................

4 years or mora ....................................................................................................

Interval between marriage and first birth

Less than 2 yaars ..................................................................................................

2 years or more ....................................................................................................

Year of first marriage

ET!Er!E

Percent

72

72

72

54

65

75

80

53

70

81

69

72

75

42

91

65

_

65

70

54

67

62

70

58

66

66

66

62

68

41

89

58

57

66

46

63

59

56

49

59

61

54

56

59

37

88

1965- 1960-

1969 1964

1955-

1959

Number in thousands

3,105

2,920

159

197

799

973

1,139

289

1,669

1,221

775

1,393

941

713

2,381

1,945

1,840

105

203

636

503

601

287

1,060

577

511

831

597

631

1,284

1,565

1,458

75

157

529

438

438

266

883

403

285

739

518

591

867

1In@jde~ ~nIy women who have had a birth (or intend a birth), were first married 1955-69, and had no Prem~ital PregnancyNOTE: Numbers may not add to totrds because of rounding; see appendix I.

19
Table 5. Percent and number of women who worked between first and second births, by year of first marriage and selected characteristics: ever-marrred women1 15-44 years of age, United States, 1973 

Characterrstic 

All women . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Race 

Black.. .................................................................................................................. 

Age at marrrage 

50 43 35 1,462 1,853 1,463 

62 49 54 200 238 257 

Less than 18 years.. .............................................................................................. 

18-19 years .......................................................................................................... 

20-21 years.. ........................................................................................................ 

22 years or more.. ................................................................................................ 

Education at marrrage 

53 46 35 284 479 383 

56 44 41 599 698 596 

49 44 38 392 491 408 

46 39 32 407 429 352 

Less than 12 years.. .............................................................................................. 

12 years ............................................................................................................... 

More than 12 years .............................................................................................. 

Previous employment 

51 43 35 410 598 505 

53 42 36 847 983 842 

47 47 43 417 523 404 

No previous employment.. ................................................................................... 43 28 22 158 227 168 

Premarrtal employment only.. .............................................................................. 50 42 32 477 665 491 

Employed between marriage and first birth ......................................................... 52 50 44 1,023 1,227 1,067 

Interval between first and second births 

Less than 3 years.. ................................................................................................ 37 29 25 394 572 538 

3-4 years .............................................................................................................. 48 40 36 456 465 417 

4 years or more.. .................................................................................................. 65 62 55 828 1,061 777 

Year of first mart-rage 

51 

Percent 

43 37 I 1,678 2,083 1,747 

1965- I 1960- I 1955- 

1967 1964 1959 

I I 

Number in thousands 

‘Includes only women who have had 2 births (or 1 birth and intend another) and were first married 19 5 5-67. 

NOTE: Numbers may not add to totals because of rounding; see appendix I. 

20 
Table 6. Percent and number of women who worked 1 year or more between the first and sacond births, by veer of first marriage and

selected characteristics: aver-married women 1 15-44 years of age who worked between the first and second bhths, United Statas,

1973

Characteristic

All women ...........................................................................................

Race

Whita ...................................................................................................................

Age at marriaW

Lass than 18 years ................................................................................................

18-19 years ..................................................................... .....................................

20-21 years ..........................................................................................................

22 years or more ..................................................................................................

Education at marriage

Less than 12 years ................................................................................................

12 yaars ...............................................................................................................

Mom than 12 years ..............................................................................................

Previous employment

No pmvious.employment .....................................................................................

Premarital employment only ..........................o.....................................................

Employed between marriaga and first birth .........................................................

Interval batween f irst and second births

Less than 3 years ..................................................................................................

3-4 years ..............................................................................................................

4 yaars or more .........................c..........................................................................

Yaar of first marriaoe

1865-

1867

1860.

1864

1955-

1968

62

61

68

55

85

58

66

61

60

67

%

61

41

53

76

70

69

76

68

70

73

70

70

:;

73

71

70

47

63

86

63

62

65

61

64

63

62

56

64

68

52

52

70

35

61

84

I

1955-

1959

Number in thousends

1,037

888

135

155

388

226

266

251

506

279

85

315

630

159

244

625

lInclude~ o~y women W. have had 2 births (or I birth and intend another) and were first m~fied 1955-67.

1,472

-

1,270

182

328

486

366

307

422

691

364

%!

853

267

284

919

1,087

908

166

231

383

257

221

279

539

277

88

259

753

191

266

653

NOTE: Numbers may not add to totals because of rounding; see appendix I.

21
Table 7. Percent and number of women who worked within 2 years of their finel birth, by yeer of finel birth and selected characteristics: ever-married women 11544 years of age whose final birth was at least 2 years ago, United States, 1973

Characteristic

All women ...........................................................................................

Race

Age at marriage

Less than 18years ................................................................................................

18-19 years ..........................................................................................................

20-21 years ..........................................................................................................

22 years or more ..................................................................................................

Education at marriage

Less than 12yaars ................................................................................................

12 years ....................................................................................o.............@o...m..mco..

More than 12 years ..............................................................................................

Previous employment

No previous employment .....................................................................................

Premarital employment only ................................................................................

Employed between marriage and first birth .........................................................

Children ever born

lor2 ...................................................................................................................

3 ..........................................................................................................................

4 or more .............................................................................................................

Year of final birth

1970-

1972

41

38

62

46

43

43

33

41

39

44

32

45

41

50

30

33

1965- 1960-

1969 1964

I

Percent

33

32

51

40

34

35

27

35

32

.35

32

33

34

39

29

28

27

26

45

36

26

26

24

24

27

31

24

26

29

33

21

25

1Include5 only women who have had a birth and intend to have no more and were first married 195S-67.

1970-

1972

1965-

1969

1960-

1964

Number in thousands

910

724

166

210

332

207

168

287

412

204

115

309

481

548

147

209

1,582

1,376

227

372

484

397

353

482

729

399

237

526

836

847

363

384

808”

714

104

222

237

183

182

173

410

234

103

231

485

464

213

143

NOTE: Numbers may not add to totals because of rounding; see appendix I.

22
2 by ~elected characteristics. Table 8. Percent, adjusted percent,l and number of women who worked during the latest pregnancy,

according to year of latest birth: ever-married women 15-44 years of age, United States, 1973

Characteristic

Education

Less than 9 years .....................................................................

9-11 years ................................................................................

12years ...................................................................................

13-15 years ..............................................................................

16 years or more .....................................................................

Husband’s income

Less than $3.000 .....................................................................

$3.000.$4.999 .........................................................................

$5.000.$5.999 .........................................................................

$6.000.$6.999 .........................................................................

$7.000.$7.999 .........................................................................

$8.000.$8.999 .........................................................................

$9.000.$9.999 .........................................................................

$lo.ooo.$l l.999 .....................................................................

$12.000.$14.999 .....................................................................

$15.000.$24.999 .....................................................................

$25,000 or more .....................................................................

Respondent not married ..........................................................

-

1 Iive birth ...............................................................................

2 live births ........................ ....................................................

3 live births .............................................................................

4 live births or more ................................................................

Age at birth of child

Less than 20 years ...................................................................

20-24 years ..............................................................................

25-29 years ..............................................................................

30-34 years ............ ..................................................................

35 years or more .....................................................................

Race and ethnicity

White. ......................................................................................

Black ....

Hispanic" ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

Other race or ethnicity ............................................................

Occupation

Professional .............................................................................

Managers .................................................................................

Sales ........................................................................................

Clerical ....................................................................................

Craftsman ................................................................................

Operatives and transport workers ............................................

Laborers, except farm .............................................................

Farmers ...................................................................................

Farm laborers ..........................................................................

Sewice .....................................................................................

Private household ....................................................................

Other .......................................................................................

See footnotes at end of table.

Percent

31

32

40

42

44

28

40

40

39

42

40

39

40

38

34

31

47

61

33

28

26

37

45

36

31

31

38

48

“36

29

47

51

34

41

46

41

30

●

36

36

28

*1

All women

Adjusted

percent 1

38

37

39

39

35

30

40

38

39

39

39

36

39

38

36

33

47

63

32

28

25

21

42

40

39

38

37

48

42

33

49

50

36

40

47

41

28

*

30

36

27

“3

Number

in

540

1,331

4,037

1,135

863

323

446

336

411

512

522

515

1,162

1,191

1,061

300

1,186

3,389

2,320

1,201

983

823

3,422

2,577

912

225

6,348

1,080

523

73

1,206

297

411

2,960

154

1,317

●61

●

●61

1,326

126

●lo

Latest birth in 1970-73

Percent

30

34

44

50

48

36

41

41

45

48

47

44

42

45

37

31

49

61

36

29

27

36

50

40

34

27

42

50

37

23

55

58

36

46

50

46

36

●

●25

39

28

●2

Adjusted

percent 1

41

40

43

47

34

27

42

41

46

43

47

42

43

44

36

32

51

63

34

28

27

24

46

43

47

39

40

53

48

32

59

57

37

44

52

48

28

*

●28

39

30

“4

Number

in

thousands

242

653

2,066

596

408

226

285

213

278

337

324

293

591

587

388

95

432

2,008

1,140

429

412

433

1,795

1,223

407

113

3,189

494

282

28

EJ53

128

206

1,542

78

663

●28

●

‘ 22

682

●62

●11

23
Table 8. Percent, adjusted percent,l and number of women who worked during the latest pregnancy,z by selected characteristics.

according to year of latest birth: ever-married women 15-44 years of age, United States, 1973 –Con.

Characteristic

Region

Place of residence

Metropolitan ...........................................................................

Nonmetropolitan .....................................................................

Yeer of latest birth3

Before 1955 or J970 ...............................................................

1955-59 or 1971 .....................................................................

1960-64 or 1972 .....................................................................

196559 or 1973 .....................................................................

197073 ...................................................................................

Interval since last birth

Less than 2 yean .....................................................................

2-2.9 yearn ...............................................................................

3-3.9 yean ...............................................................................

4-4.9 yean ...............................................................................

5.5.9 yearn ...............................................................................

6 years or more .......................................................................

No births .................................................................................

Percent

36

38

43

35

38

39

55

37

32

36

42

24

28

32

35

31

45

61

All women

Adjusted

percent 1

36

39

41

36

38

39

*36

33

34

39

41

23

27

32

35

33

46

61

Number

in

thousands

1,586

2,072

2,856

1,455

5,585

2,324

*53

367

1,161

2,331

3,976

1,080

1,103

837

498

303

737

3,390

Latest birth in 1970-73

Percent

40

41

48

36

41

45

40

45

42

40

...

26

28

35

34

35

46

61

Adjusted

percentl

41

42

45

37

41

44

41

45

42

39

...

26

27

34

34

38

47

61

Number

in

thousands

765

1,048

1,519

661

2,749

1,242

680

1,161

1,164

756

...

430

454

383

185

140

397

2,009

lAdju5ted by M~lti~le Cla5~ificetion Analysis for religious denomination, religious pi3rtiCipatiOn, and all other variables in this table;

see text and armendix I for further discussion.

z[nclude~”only pregnancies that ended in a live birth.

3Earljer date on each Iine refers to columns headed “AI] women,”

1970-73. ”

and later date refers to columns headed “Latest birth in

NOTE: See appendix II for defiiitiona of characteristics, and appendm I for discussion of rounding errors.

24
Table 9. Percent, adjusted percent,l end number of women who worked during the last trimester of the latest meanancv.z bv selected

characteristics, according to year of latest birth: ever-married women 15-4~ years of age who worked during the latest pregnancy,

.-. . .

United States, 1973

Characteristic

Less than 9 yearn .....................................................................

9-11 yearn ................................................................................

12 yearn ...................................................................................

13-15 yeaE ..............................................................................

16 years or more .....................................................................

Husband’s income

Lass than $3.000 .....................................................................

$3nm*999 .........................................................................

$5.w4599 .........................................................................

$6.W46399 .........................................................................

$7.m47999 .........................................................................

$6.0m*83w .........................................................................

$9.wti9999 .........................................................................

$lotm.$ll#999 .....................................................................

$12.~~14.999 .....................................................................

$15.~.$24S9 .....................................................................

$25,000 or more .....................................................................

Respondent not married ..........................................................

Parity

1 live hrth ...............................................................................

2 live births .............................................................................

3 live births .............................................................................

4 live births or more ................................................................

Aoe at birth of child

Less than 20 yearn ...................................................................

20-24 yea~ ..............................................................................

25-28 years ..............................................................................

30-34 yearn ..............................................................................

35 years or more .....................................................................

Race and ethnicity

White .......................................................................................

Black ..................................................................................... ..

Hispanic ..................................................................................

Other race or ethnicity ............................................................

Occupation

Professional .............................................................................

Managers .................................................................................

sales ........................................................................................

Clerical ....................................................................................

Cratiman ................................................................................

Operatives and transport workers ............................................

Laborers, except farm .............................................................

Farmers ...................................................................................

Farm laborem ..........................................................................

Service .....................................................................................

Private household ....................................................................

Otier .......................................................................................

See footnotes at end of table.

Percenl

34

35

49

44

51

44

51

54

39

46

45

48

41

50

40

48

44

50

42

42

37

40

44

46

48

47

45

41

46

69

49

63

42

50

42

38

*

*

34

58

*

All women

Adjustec

percentl

38

41

48

42

45

46

52

54

42

44

46

47

41

48

36

46

47

50

42

43

36

39

43

47

49

51

44

47

●

48

67

49

64

42

48

46

39

*

●

36

61

●

Number

in

thousands

181

472

1,981

498

438

230

131

181

160

235

232

244

472

590

424

142

516

1,690

%6

510

360

327

1,493

1,185

433

106

2,816

438

238

50

580

186

173

1,476

●84

497

*

●

454

74

●

Latest birth in 1970-73

Percent

38

38

53

42

58

45

56

60

42

50

48

57

47

50

42

55

42

53

46

44

34

38

48

50

54

50

49

38

51

●

55

72

52

52

38

43

●

●

32

●

*

Adjusted

percentl

41

47

53

39

44

47

56

63

45

50

49

55

47

46

39

46

49

54

47

43

28

36

45

51

62

58

48

47

49

●

55

73

60

50

42

46

#

*

34

●

●

Number

in

thousands

90

249

1,105

248

238

129

88

128

116

168

157

166

279

284

161

52

182

1,060

521

187

142

162

888

608

222

●58

1,555

188

142

*

311

92

108

785

*3O

286

●

*

219

*

●

25
Table 9. Percent, adjusted percent,l and number of women who worked during the last trimester of the latest pregnancy, 2 by selected

characteristics. accordina to vear of latest birth: ever-married woman 15-44 vears of a~a who workad durirm the Iatast cwaanancv.

United States,” 1973–CO;. “

All women

Region

Northeast ................................................................................

North Central .....................................................!.. ..................

South ......................................................................................

West ........................................................................................

Place of residence

Metropolitan ...........................................................................

Nonmetropolitan .....................................................................

Year of latest birth3

Before 1955 or 1970 ...............................................................

1955-59 or 1971 .....................................................................

1960-64 or 1972 .....................................................................

1965-69 or 1973 ;....................................................................

1970.73 ...................................................................................

Percent

45

42

46

47

45

46

28

24

45

43

48

Adjusted

percentl

45

42

45

48

44

46

27

24

45

44

48

Number

in

thousands

704

669

1,306

677

2,504

1,061

*I5

88

522

710

1,921

.-.

—

Latest birth in 1970-’73

Percent

53

46

47

50

48

49

44

49

46

56

...

Adjusted

percentl

48

47

49

51

48

49

47

48

48

52

...

Number

in

thousands

401

487

708

328

1,317

604

394

572

532

423

...

I Adju5ted ~~ ~ultiP1e Clw5ifjcation Analysis for ~eligiom denomination, religious participation, and all other variables in this table;

see text and appendix I for further dkcussion.

21nc]udes only pregnancies that ended in a live birth.

3Earfier date on each line refers to COlumnS headed “~1 women?”

1970-73. ”

and later dste refers to columns headed “Latest birth in

NOTE: See appendix II for definitions of characteristics.

26
Table 10. Number of woman and parcent employed during aech month of tha Iatast prugnamcyr 1 and madian number of monttrs employad during that pregnancy, by race, education, and parity: ever-married women 15-44 years of age who worked during the latest

pregnancy whose latest birth was less than 2 years ago, Unitad States, 1973

Month of pregnancy

AH women ................................

Before pregnancy ......................................

2d .............................................................

3d .............................................................

4th ............................................................

Median m~ths employed ........................

Education I

Puity

Total*

Whita Black Lees than 12 yews

More than ,

2

I

3 or

12 years 12yeera more

II I 1 I 1 1 I I

Number in thousands

2,280 # 2,033 I 242 t 533

100.0

88.8

93.2

86.5

76.4

69.4

61.0

48.6

32.7

19.2

100.0

96.6

93.4

88.5

76.7

70.0

61.5

49.2

33.5

19.1

100.0

98.6

91.6

85.8

71.8

84.8

56.1

42.1

25.9

19.2

100.0

95.1

80.4

80.8

67.0

58.6

50.3

38.6

26.6

20.9

1,175 I 583 I 1,208 I 628 I 453

Percent

100.0

97.0

84.4

87.6

77.9

74.6

63.2

51.7

31.7

I a9

Numbar

100.0

97.8

93.6

8fJ.6

81.7

88.1

62.3

51.4

40.3

18.2

100.0

98.8

96.0

80.2

81.9

74.1

66.4

54.6

35.8

20.5

100.0

93.7

88.5

82.2

70.6

62.8

54.4

40.9

27.7

14.2

100.0

95.8

91.1

82.9

68.5

88.4

55.5

43.3

31.2

22.5

6.0 7.1

I

7.1 7.2 6.3 6.5

lJn~ludes only pregnancies that ended in a live IMh.

21ncludea races other than white or black.

27
Table 11. Percent, adjusted percent,l and number of women who worked since the latest birth, by selected characteristics, according to

year of Iatast birth: ever-married women 1544 years of age, United States, 1973

Characteristic

Education

Lees than 9 years .....................................................................

9-11 years ................................................................................

12 years ...................................................................................

13-15 years... ...........................................................................

16 yaars or more .....................................................................

Husband’s income

Less than $3,000 .....................................................................

?$3,000-$4,999 ................................................................ .........

$5.000.$5.999 .........................................................................

$6.QO0.$6.999 .........................................................................

$7.00Q.$7B99 .........................................................................

$8.000.$8399 .........................................................................

$9.mo49399 .........................................................................

$10,000-$11,998 .....................................................................

$12,000-$14,999 .....................................................................

$15,000-$24,999 .....................................................................

$25,000 or more .....................................................................

Respondent not married ..........................................................

Parity

1 live Mrth ...............................................................................

2 live births .............................................................................

3 live births .............................................................................

4 live births or more ................................................................

Age at birth of child

Less than 20 yeers ...................................................................

20-24 yaars ..............................................................................

25-29 years ..............................................................................

30-34 years ..............................................................................

35 yaars or more .....................................................................

Rata and ethnicity

Black .......................................................................................

Hispanic ..................................................................................

Other race or ethnicity ..........................................................

Occupation

Professional .............................................................................

Managers .................................................................................

Sales ................................................................................... .....

Clerical ....................................................................................

Craftsman ..........................................c.c...................................

Operatives and transport workers ............................................

Laborers, except farm .............................................................

Farmers ...................................................................................

Farm laborars ........................ ..................................................

Sewice ................o....................c...............................................

Private household ....................................................................

Percent

52

61

5B

56

62

50

57

60

53

64

55

57

55

57

55

45

79

65

57

56

54

73

64

54

47

59

57

73

55

50

63

75

64

53

70

68

58

*

72

66

57

1

All women

Adjusted

percentl

52

56

59

58

65

53

60

61

57

65

57

59

57

57

55

42

71

62

56

56

60

74

63

54

4B

46

57

67

62

61

65

73

65

55

68

66

51

*

62

64

56

2

Number

in

thousands

905

2,538

5,653

1,514

1,216

578

635

503

559

780

717

753

1,598

1,767

1,716

436

1,993

3,611

4,007

2,401

2,042

1,624

4,667

3,665

1,383

429

9,521

1,642

799

125

1,617

437

773

3,826

234

2,185

118

*

121

2,431

256

*1 o

Latest birth in 1970-73

Percent

35

45

43

39

42

34

42

50

40

50

45

44

38

3B

33

2B

63

51

40

35

33

61

46

35

35

24

40

56

42

35

43

50

46

37

50

53

55

*

62

51

43

2

Adjusted

percentl

34

39

44

43

45

33

43

4B

41

44

44

46

39

40

36

30

57

47

41

37

38

59

43

37

40

31

40

52

50

45

52

54

47

36

50

52

*4O

*

54

49

41

*

Numbar

in

thousands

2B2

865

2,019

465

357

214

291

260

247

362

311

293

535

496

346

B5

555

1,680

1,267

518

504

733

1,651

1,070

419

101

3,038

553

320

43

440

111

263

1,241

78

764

*43

*

*54

892

92

*11

See footnotes at end of table.

28
Table 11. Percent, adjusted percent,l and number of women who worked since the latest birth, by selected characteristics, according to

year of latest birth: ever-married women 1544 years of age, United States, 1973 – Con.

Region

Northeast ................................................................................

North Central ..........................................................................

west........................................................................................

Pltw of residence

Metropolitan ...........................................................................

Nonmetropoliterr ......... ........ ....................................................

Year of latest hirth2

Before 1955 or 1970 ...............................................................

1965-59 or 1971 .....................................................................

1680-84 or 1972 .....................................................................

1885-69 or 1973 .....................................................................

f970.73 ...................................................................................

Additional children expected

None .......................................................................................

1..... .........................................................................................

2 or more ................................................................................

Percent

52

5s

62

62

57

61

100

88

78

86

42

56

5s

63

All women

Adjusted

percentl

54

57

61

61

58

60

78

83

79

68

42

57

59

●

60

Number

in

2,291

3,053

4,119

2,577

8,378

3,635

97

874

2,826

4,273

3976

4,s85

2,562

4,862

latest birth in 1970-73

Percent

32

40

48

44

41

45

55

53

39

16

...

35

47

43

Adjusted

percentl

37

38

45

45

41

43

%

38

14

...

41

44

41

Number

in

thousands

612

1,022

1,519

807

2,749

1,242

1,224

1,367

1,081

302

...

1,110

1,477

1,355

lAdjusted by MuItipIe cl=~fjcation AnaIySiS for religious denomination, religious participation, and all other ~fib~~ in th~ tabte;

CC%? to t and appendix I for further dmussion. #Earlier date on each line refera to columns headed “MI women,” and later date refers to columns headed “Latest biith in

1970-73.”

NOTE: See appendix II for definitions of characteristics, and appendix I for discussion of rounding errors.

28
Table 12. Percent, adjusted percent,l and number of woman who returned to work since the Iatast birth, by selected characteristics,

eccordi ng to year of latest birth: ever-married women 1544 years of age who worked during the latest pregnancY,2 United States, 1973

Characteristic

Education

Less than 9 years .....................................................................

9-11 years ................................................................................

12 years ...................................................................................

13-15 years ..............................................................................

16 years or more .....................................................................

Husband’s income

Less than $3.000 .....................................................................

$3.000.$4.999 ............u.............................. ..............................

$5.000.$5n999 .........................................................................

$6,000-$6,999 .........................................................................

$7,000-$7,999 .........................................................................

$8.000.$8.999 ............................. ............................................

$9,000-$9?899 .........................................................................

$10,000-.$11999 .....................................................................

$12,000-$14,988 .....................................................................

$15,000-$24,999 .....................................................................

$25,000 or mora .....................................................................

Respondent not married ..........................................................

Parity

1 live birth .............................................................................~.

2 live births .............................................................................

3 live birtha .............................................................................

4 live births or more ................................................................

Aga at birth of child

Less than 20 years ...................................................................

20-24 years.. ............................................................................

25-28 years ..............................................................................

30-34 years ............i...l ...................................l.l .......................

35 years or more ...........i ..........................lc.............................

Race and ethnicitv

White .......................................................................................

Black .......................................................................................

Hispanic ..................................................................................

Other race or ethnicitv ............................................................

Occupation

Professional .......................................................... ...................

Managers .................................................................................

Sales ................................!. ......................................................

Clerical ...............!. ...................................................................

Craftsman ................................................................................

Operatives and transport workers ............................................

Laborers, except ferm .............................................................

Farmers ...................................................................................

Farm laborars ..........................................................................

Service .....................................................................................

Privete household ....................................................................

Other .......................................................................................

See footnotes at end of table.

‘arcent

75

79

73

72

77

67

73

73

69

78

69

71

72

71

77

73

87

71

74

80

81

87

74

72

75

68

73

64

73

100

74

83

74

69

79

60

70

83

79

78

92

All women

~ercentl

65

71

74

76

87

64

74

73

71

81

72

73

75

73

75

71

81

71

75

79

82

90

76

71

70

64

73

80

76

95

72

81

77

70

77

81

66

73

79

78

85

in

housands

398

1,066

2,951

814

661

350

188

245

282

399

355

361

828

837

815

215

1,020

2,399

1,737

972

788

712

2,511

1,855

677

153

4,568

887

377

72

681

245

305

2,036

121

1,046

*42

*49

1,055

99

*9

Last birth in 1970-73

‘ercent

63

67

60

57

66

41

62

66

59

68

54

61

59

58

58

65

80

58

65

64

70

78

58

60

69

54

59

73

66

*

63

61

57

53

61

72

79

82

70

70

*9 I

ldjusted

)ercent 1

46

56

63

63

71

38

64

68

59

64

58

64

60

60

59

63

73

59

65

62

65

79

59

60

63

51

60

68

69

*

66

65

61

53

63

71

*7 I

77

66

62

*6(1

Number

in

thousands

149

439

1,251

33q

271

117

96

141

163

228

177

174

35Q

340

222

*61’

347

1,16Q

736

272

293

332

1,049

730

284

*62

1,872

363

184

*

357

78

119

810

*48

478

*22

*I8

480

*44

*5

30
Table 12. Percent, adjusted percent,l and number of women W+IO returned to work since the latest birth, by selacted characteristics,

according to year of latest birth: avar-married women 1544 yeara of a~ who worked during the latest pregnency,2 United States,

1973 – Con.

Charectaristic

Region

Northeast ................................................................................

North Central ..........................................................................

Wast ........................................................................................

Place of rasidence

Metropolitan ...........................................................................

Nonmetropolitin .....................................................................

Year of latest birth3

Before 1955 or 1970 ...............................................................

1955-59 or 1971 .....................................................................

1960-64 or 1972 .....................................................................

1965-69 or 1973 .....................................................................

1970.73 ...................................................................................

Additional children expected

None .......................................................................................

1..............................................................................................

2 or more ................................................................................

Percent

71

72

77

78

74

77

100

94

93

64

62

75

68

79

All women

Adjusted

percentl

71

73

77

77

73

78

93

90

90

85

62

75

74

75

Number

in

1,111

1,490

2,187

1,123

4,117

1,810

*55

345

1,078

3,341

2,460

2,084

1,583

2,219

Latest birth in 1970-73

Percent

55

57

68

63

60

66

77

74

60

28

...

61

59

66

Adjusted

percentl

57

56

67

63

59

66

75

74

61

28

...

61

60

64

Number

in

thousands

416

603

1,024

414

1,646

813

690

864

694

212

...

708

947

800

lAdjusted by Mu@Ie Clarification ~alysi~ for re]i~ow denomination, religious participation, and all other variables in th~ table;

see text and appendix I for further discussion.

21nc]udes OnIY pre~ancies that ended in a live b~th3&fier date on each line refera to columns headed “~ women, ,, and later date refers to columns headed “Latest birth in

1970 -73.”

NOTE: See appendix H for definitions of characteristics.

31
Table 13. Number and cumulative percent of women who worked since the Ietest birth, by number of months” since latest birth,

according to race, education, and parity: aver-married woman 1544 years of age whose latest birth was 12-23 months SLSO,United

Statas, 1973

Months since latest birth

All women ................................

2 ...............................................................

4 ...............................................................

6 ...............................................................

8 ...............................................................

10 .............................................................

12 .............................................................

E

Race

Total 1

Wh ita Black

2,686 n 2,388

I

5.2 5.2

14.9 14.0

20.0 18.6

24.6 22.9

28.7 27.1

-u_l13

Education I Perity

E51c4E2

Number in thousands

1- 1 2

268 I 733 I 1,390 I 562 I 1,039 I 833

Cumulative percent

*5.6 *7.9 ●4 .7 *3.O *3.6 *5.7

19.7 16.8 15.3 *11.3 16.3 13.5

30.6 21.0 21.5 14.6 23.3 17.0

38.2 25.9 26.5 18.1 31.3 18.8

41.3 30.6 30.6 21.4 34.0 24.4

43,6 33.8 32.9 23.5 36.9 26.5

3or’

more

815

*6.7

14.5

18.8

21.9

26.2

38.8

Table 14. Number and cumulative percent of women who returned to work after the latest birth, by months since latest birth, accorsfhg

to race, education, and parity: ever-married women 1544 years of age who workad during the latest pregnancy,l United States,

1973

*

Months since latest birth

All women ................................

............................................. ..................

: ...............................................................

6 ...............................................................

8 ...............................................................

10 .............................................................

12 .............................................................

II Race “1 Education I

Parity

Total 2

White Black Less than 12 years

More than ,

2

3 or

12 years 12 years more

Number in thousands

1,165 II 1,028 ! 124 I 266 I 619 I 280

Cumulative percent

m

603

*4.5

20.9

30.8

42.2

43.7

46.0

326 I 236

‘14.2

27.9

33.9

36.9

42.8

45.6

*1 7.9

38.0

46.4

49.7

58.8

63.5

lrncludes onl y pregnancies that ended in a live ~~th.

21ncludes races other than white or black.

32
APPENDIXESCONTENTS

L

IL

IIL

L

IL

L

IL

IJ.L

IV.

TeefmicfdNotes..............................................................................................................................

Background ...............................................................................................................................

Statistical Design .......................................................................................................................

Measurement Process ................................................................................................................

Data Reduction .........................................................................................................................

Reliability of Estimates .............................................................................................................

Nonsarnpling Error ....................................................................................................................

Interview Nonresponse ..............................................................................................................

Item Nonresponse .....................................................................................................................

The Open Interval Problem .......................................................................................................

34

34

34

35

35

35

36

40

40

42

Definition of Terms ........................................................................................................................ 44

Items on Questionnaire Relating to Employment of Mothers in Inta-vrds Before, Between, and

After Births ................................................................................................................................. 49

LIST OF APPENDIX FIGURES

Relative standard errors for numbers of women, by race: National Survey of Family Growth,

Cycle I ......................................................................................................................................... 37

Relative standard errors for percent of total and white women (base of percent shown in curve in

thousands): National Suivey of Family Growth, Cycle I ............................................................ 38

LIST OF APPENDIX TABLES

Approximate standard errors for estimated percents expressed in percentage points for white and

total women: National Survey of Family Growth, Cycle 1 ................... ...................................... 39

Approximate standard errors for estimated percents expressed in percentage points for black

womem National Survey of Family Growth, Cycle I .................................................................. 39

Approximate standard errors for estbnated numbers for white and total women: National Survey

of Family Growth, Cycle I ........................................................................................................... 39

Approximate standard errors for estimated numbers for black women: National Survey of

Family Growth, Cycle I ................” ............................................................................................. 39

33
APPENDIX I

TECHNICAL NOTES

Background

This report is one of a series of statistical

reports based cm information collected from a

nationwide sample of wornen by the National

Survey of Family Growth, conducted by the

National Center for Health Statistics.

The National Survey of Family Growth

(NSFG) utilizes a questionnaire to obtain demographic information and information on fertility, family planning, and health factors related

to childbearing. As data relating to various

subjects within these broad topics are tabulated

and analyzed, separate reports are issued. The

present report is based on data collected in the

first cycle of the survey which was centered on

September 1973.

The population covered by the sample for

the NSFG is women 15 to 44 years of age living

in households in the conterminous United States

at the time of interview who were ever married

or had offspring living with them. The sample

did not include women living in institutions or

group quarters. Personal interviews were conducted by the staff of the National Opinion

Research Center (NORC), Chicago, beginning in

July 1973 and ending in February 1974.

Statistical Design

The sampling plan for the survey was a

multistage probability design. Black households

and households of all other races were selected

at different probabilities so that the sample was

composed of about 40 percent black women and

60 percent women of all other races. The sample

was designed so that tabulations could be

provided for each of the four geographic regions

of the United States.

34

The first stage of the sample design consisted

of drawing a sample of primary sampling units

(PSU’S). A PSU consisted of a county, a small

group of contiguous counties, or a standard

metropolitan statistical area as defined by the

U.S. Bureau of the Census in March 1971. The

second and third stages of sampling were used to

select several segments (clusters of about 100

dwelling units) within each PSU. A systematic

sample of dwelling units was then selected from

each segment. Each sample dwelling unit was

visited by an interviewer who listed all household members. If a woman under 45 years of

age, ever married, or with offspring in the

household, was listed as being in the household,

an extended interview was conducted. If more

than one woman in the household met the .

eligibility criteria, one of the women was randomly selected for an extended interview.

Since the design of the NSFG was a complex

multistage probability sample, the derivation of

estimates involved three basic operations:

2.

2.

Injlation by the reciprocal of the probability of selection. —The probability of

selection is the product of the probabilities of selection from each step of

selection in the design (PSU, segmentstratum, listing unit, household, and sample persons within household).

Nonresponse adjustment.–The estimates

were inflated by a multiplication of two

factors. The first has the number of

sample households in a given PSU and

stratum as its numerator and the number

of households screened in the PSU and

stratum as its denominator. The second

factor has as its numerator the number of
screened households having an eIigible

woman of a specific age and race class

and PSU group, and as its denominator,

the number of women actually interviewed in the same age and race class and

PSU. Screener response for the total

survey was 89.8 percent and interview

response was 90.2 percent for the total

sample, yielding an overall response rate

of approximately 81.0 percent.

3. Poststratificatt’on by marital status-agerace.—The estimates are ratio adjusted

within each of 12 age-race cells to an

independent estimate of the population

for ever-married women. These independent estimates were derived from the

U.S. Bureau of the Census Current Population Surveys of 1971-73. The number

of single women with offspring Iiving

with them were inflated by steps 1 and 2.

All figures are individually rounded; aggregate figures are rounded to the nea-est thousand.

The sums of aggregates and percents may not

add up to the total due to the rounding.

The effect of the ratio-estimating process is

to make the sample more closely representative

of the population of women under age 45 years,

living in households in the conterminous United

States, and ever married or with offspring living

with them. The final poststratification reduces

the sample variance of the estimates for most

statistics.

Descriptive material on the sampling design

and estimation procedures may be found in

another reports

Measurement Process

Field operations for the survey were conducted by NORC as agent for NCHS. Their

responsibilities included pretesting the interview

schedule, selecting the sample, interviewing

respondents , and carrying out quality controI

checks. The questionnaire was pretested in

November 1972 and subsequent smaller field

trials were held in March 1973. Interviewers

were trained for a week prior to fieldwork and

had their first few schedules reviewed thoroughly. During the first part of the fieldwork,

NOTE: A list of references follows the text.

each interview schedule was reviewed for the

completeness of certain key items and more

intensive review and folIowup were performed if

errors were discovered. Review and followup

were reduced to a sample of each interviewer’s

work in the later part of the fieldwork. A

10-percent sample of all households with telephones was recontacted to verify the interview

and the accuracy of a few items. All of these

operations were monitored by NCHS.

The parts of the interview schedule applicable to this report are reproduced in appendix

HI. The compIete schedules are avaiIable upon

request. Two different forms were used, one for

interviewing currently married women and the

other for interviewing widowed, divorced, separated, or single women with their own children

living with them. The two forms differ mainly in

wording when reference is made to the husband;

there are a few questions in each schedule that

do not appear in the other.

Data Reduction

Coding and keying were done by NORC and

the U.S. Bureau of the Census. Each coder’s

work was systematicalIy sarnpIed for verification. Keying at the Bureau of the Census was

performed on key-to-disk equipment programed

to reject invalid entries. Each keyer’s work was

systematically sampled for verification. The data

were edited by the Bureau of the Census and

NCHS to minimize internal inconsistencies.

After editing, value entries were imputed to

cases with missing data on an item-by-item basis.

No item with more than 15 percent missing data

was included in the imputation. The imputed

value entry for a case was selected from a

randomly chosen case with simiktr characteristics such as race, age, and marital status, using

a procedure known as “hot deck” imputation.

Reliability of Estimates

Since the statistics presented in this report

are based on a sample, they may differ somewhat from the figures that would have been

obtained if a compIete census had been taken

using the same questionnaires, instructions,

interviewing personnel, and field procedures.

This chance difference between sample results

and a complete count is referred to as sampIing

35
.+

error and is measured by a statistic called the

standard error of estimate. The relative standard

error of an estimate is obtained by dividing- the

standard error of the estimate by the estimate

itself and is expressed as a percent of the

estimate. Included in this appendix are charts

and tables from. which the relative standard

errors can be determined for estimates shown in

this report. In order to derive relative errors that

would be applicable to a wide variety of health

statistics and that could be prepared at a

moderate cost, a number of approximations

were required. As a result, the charts provide an

estimate of the approximate relative standard

error rather than the precise, error for any

specific statistic. The standard errors were computed using a progedure known as balanced

half-sample replication.g

The chances are about 68 out of 100 that an

estimate from the sample would differ from a

complete census by less than the standard error.

The chances are about 95 out of 100 that the

differences between the sample estimate and a

complete count would be less than twice the

standard error. In this report numbers and

percents that have a standard error more than

25 percent of the estimate itself are considered

“unreliable.” They are marked with an asterisk

to caution the user, but may be combined to

make other types of comparisons of greater

precision.

In this report, sample stati~ics are-compared

among subgroups or across yearn., using the

normal deviate test at the .05 level of confidence. A statistically significant difference

among comparable proportions or other statistics from two or more subgroups is one sufficiently greater than zero that a difference of

that size or larger would be expected in less than

5 percent of repeated samples of the same size

and type if there were no true difference in the

populations sampled. If the observed difference

or a larger one could be expected in more than 5

percent of repeated samples, one cannot be

sufficiently confident to conclude that there is a

true difference in the populations. When an

observed difference is sufficiently greater than

zero to be statistically significant, the true

difference in the population is estimated to lie

NOTE: A list of references follows the textbetween the observed difference plus or minus

two standard errors of that difference in 95 out

of 100 samples.

When two or more sample statistics are

compared and the y have only small, statistically

nonsignificant differences among them, they

may be referred to as the “same” or “similar.”

However, where a substantial difference observed is found to be not statistically significant,

one should not conclude that no difference

exists, but simply that such a difference cannot

be established with 95-percent confidence from

this sample. Observed differences that are

described in terms such as “greater,” “less,”

“larger, “ “smaller,” etc., have been tested and

found statistically significant. Lack of comment in the text about any two statistics does

not mean the difference was tested and found to

be not significant.

The standard error of a difference between

two comparative statistics, say the proportion

with characteristic M among black women compared with white women, is approximately the

square root of the sum of the squares of the

standard errors of the statistics considered separatel y.

A formula for the standard error of a

difference, d = PI - P2, is

u/j = <(PI’ J’pl)z + (P*VP2)2

where PI is the proportion for one group, P2 the

proportion for the comparative group, and VP~

and ‘Vp z are the relative standard errors of PI

and P2, respectively. This formula wiIl represent

the actual standard error quite accurately for the

difference between separate and uncorrelated

characteristics, although it is only a rough

approximation in most other cases. The relative

standard error of various proportions can be

estimated from figures I and II and tables I-IV

for statistics based on the NSFG.

Nonsampling Error

In addition to sampling error, the survey

results are subject to several sources of potential

nonsampling error, including interview nonresponse, nonresponse to individual questions

within the interview, inconsistency of responses

to individual questions, respondent error or

misreporting, and errors of recording, coding, or

36
Figure 1. Relti-va standard errors for numbers of women, by race: National Survey of Familv Growth, Cvcle I

Lu

a

A’ 3 4 56789

A’ A’

3 456789 3 4 56789A 2 3 456789A 2 3 456789

1 10 100 1@O

ESTIMATED NUMBER OF WOMEN (IN THOUSANDS)

Example of use of chart: An aggregate of 2 million women (on the scale at the bottom

relative standard error of 4.8 percent, or a standard error of 96,000 (4.8 percent of 2 million).

105)0

of the chart) of all races has a
Figure 11. Relative standard errors for percent of total and white women (base of percent shown in curve in thousands): National

I.1.l

>

Survey of Family Growth, Cycle I

100

90

80

70

60

50

$0

30 L

u ml I I N I

.“. I <1 I ml I I i 1 1

*

1111

20

10

9

8

7

6

5

4

3

2

1

.9

.a

.7

.6

.5

1 I I I [ I I I 1 1 1~

.-

.4

.3

.2

‘~ 2 3 45678’! 2 3 45678:~o 2 3 ““’:~m

ESTIMATED PERCENT

Example of use of chart: An estimate of 10 percent (from the scale at the bottom of the chart)

of a pop;latiok sub~-oup of 1 million women (filth curve from the top) has a relative standard error

of 20.0 percent, or a standard error of 2.0 percent (20.0 percent of 10 percent).
Table 1. Approximate standard errors for estimated percents expressed in percentage points for white and total women: National

Survey of Family Growth, Cycle I

>

Base of parcent

lm.m ..............................................................................................................

m.m ..............................................................................................................

l.m.m ...........................................................................................................

Estimated percent

2 or

98

3.0

1.3

0.9

0.5

0.4

0.3

0.3

—

5 or

95

.

4.6

2.1

1.5

0.8

0.6

0.5

0.5

10or

90

f

30 or 40 or

70 50

9.7 10.4

4.3 4.6

3.1 3.3

1.8 1.8

1.4 1.5

1.2 1.2

1.0 1.0

20 or

80 50

10.6

4.7

3.3

1.9

1.5

1.3

1.1

6.4

2.8

2.0

1.2

0.9

0.8

0.6

8.5

3.8

2.7

1.5

1.2

1.0

0.8

5;ooo;fMo ...........................................................................................................

7.m.m ...........................................................................................................

lo.m.m .........................................................................................................

Table 11. Approximate standerd errors for estimated percents expressad in percentage points for Mck women: National Survey of

Family Growth, Cycle I

Estimated percent

5 or

95

12.3

8.7

3.9

2.7

1.6

1.2

1.0

0.9

10 or

80

17.0

12.0

5.4

3.8

2.2

1.7

1.4

1.2 E

30 or 400r ~

70 80

25.9 27.7 28.3

~8.3 19.6 20.0

8.2 8.8 8.9

5.8 6.2 6.3

3.3 3.6 3.6

2.6 2.8 2.8

2.2 ~3 2.4

1.8 2.0 2.0

Base of percent

5@ ..................................................................................................................

lo.m ................................................................................................................

60,000 ................................................................................................................

2 or

98

7.9

5.6

2.5

1.8

1.0

0,8

0.7

0.6

20 or

80

22.6

16.0

7.1

5.1

2.9

2.3

1.9

1.6

m;m..............................................................................................................

l.m.m ...........................................................................................................

Table ill. Approximate standard errors for estimated numbers TeblelV. Approximate standard errors for estimated numbers

for white and total women: National Survey of Family for black women: National Suwev of Family Growth,

Growth, Cycle I

—

Cycle I

Relative

standard

error

Relativa

standard

error

Standard

error

Standard

error

Size of estimate Size of estimate

50,000 .................................................

Ioo,ooo ...............................................

200,000 ...............................................

5U0,000 ...............................................

l,m#m ............................................

2,000,000 ............................................

5,000,000 ............................................

Io,ooo,ooo ..........................................

20,000,000 ..........................................

30.0

21.2

15.0

9.5

6.7

4.8

3.0

2.2

1.5

15,000

21,000

30,000

47,000

67,000

95,000

151,000

216,000

311,000

25,000 .................................................

50,000 .................................................

100,OOO ...............................................

150,000 ...............................................

250,000 ...............................................

350,000 ...............................................

500,0Q0 ...............................................

750,000 .. ................................. ... ... ......

l,m,w ............................................

25.3

17.9

12.7

10.3

8.0

6.8

5.7

4.7

4.0

6,000

9,000

!3,000

16,000

20,000

24,000

28,000

35,000

40,000

39
keying by survey personnel. It is impossible to

measure the extent of nonsampling errors

accurately. Although some useful approximate

measures can be made of some types of nonsampling error, the survey must rely upon several

quality control procedures and other methods

incorporated into the survey design to minimize

nonsampling error.

Estimated numbers of women representing

the numerators of the percents shown have been

presented in the tables for the readers’ convenience. These estimates are subject to somewhat

larger rounding differences than usual, since

they are the products of the whole percents

shown and the corresponding subpopulations of

ever-married women 15 to 44 years of age expressed in thousands. Column sums may occasionally differ from their totals by as much as a

percentage point or fractionally higher. However, individual figures will be rounded within

half a percentage point of the sample value,

which is generally well within the sampling variabilityy of the estimate.

Interview Nonresponse

Interview nonresponse, or the failure to

obtain whoIe interviews, arises from several

sources—incomplete Iisting of households for the

samplirijg frame, inability to screen all sample

households for eligible respondents, and inability to complete a full interview. Completeness of

listing cannot be tested directly as it requires an

independent, accurate accounting of the households that should have been listed. In the NSFG+

listing accuracy was tested at the time of

screening by use of the “half open interval”

check for missed households; that is, at designated sample households, the interviewer was

required to check for dwelling units between the

sample household just screened and the next

listed dwelling unit. This procedure resulted in

the addition of 781 missed units or an additional

2.4 percent to the original sample of dwelling

units to be screened.

Of the original sample of 32,818 dwelling

units to be screened, 3,820 were found to be

vacant, not dwelling units, or group quarters. Of

the remaining dwelling units, 9.7 percent were

not successfully screened. This included 2.3

percent refusals to have the household members

listed; 1.6 percent with language problems,

illness, or otherwise unavailable -in ‘the field

period; 4.6 percent where no one could be

found at home; and 1.1 percent for other

reasons such as refused access to the unit.

Of the 26,177 households for which screening was completed, 10,879 were found to

contain an eligible respondent. However, interviews were not completed in 9.8 percent of

these cases because of refusals by the eligible

respondents (5.0 percent ); language, illness, and

related problems (2.0 percent ); and no contact

after repeated calls (2.7 percent).

The nonresponse adjustment for interview

nonresponse described above imputes to nonresponding dwelling units and women the characteristics of similar respondent dwelling units

and women.

{tern Nonresponse

Nonresponse to individual questions (item

nonresponse) was less than 2 percent for about

half (51 percent) of the items. Item nonresponse

occurred when the person refused to answer the

question, when the person did not know the

answer to the question, when the question was

erroneously not asked or the answer not recorded by the interviewer, and when the answer

was uncodable. For 37 percent of the items,

nonresponse occurred between 2.0 and 10.0

percent. For the remaining 12 percent of the

items, nonresponse was greater than 10 percent

of persons eligible to answer the items. IHalf of

these high nonresponse items were concentrated

in two areas-detailed income questions and

questions about the reasons for switching from

one contraceptive method to another. The remaining high nonresponse items were generally

those asked of small numbers of persons.

The amount of missing data or imputed

values for various items will usually be shown

with the definition in appendix II, especially

where it is substantial. Some illustrative items

with their associated nonresponse rates are: the

number of children ever born (pari~y) (no

missing data), intentions about having another

child (O.7 percent), whether no contraceptive

method was used or whether contraception was

stopped in order to become pregnant (1.9

40
percent), highest grade of school attended (O.1

percent), and total family income (6.8 percent).

For most items, an adjustment for missing

data was made by one of four imputation

procedures. In order of frequency employed

they were: (1) “hot deck” imputation, (2)

imputation from a sorted file, (3) editing from

other data within the same case, and (4)

allocation based on technical judgments.

“Hot deck” imputation refers to a procedure

in which the file is first randomized. Next a

matrix is created for values of items (e.g., race,

age, and marital status) judged to be correlated

with the item to be imputed (e.g., number of

times married). A reasonable “cold deck” value

(e.g., 2 = married twice) is assigned to each cell

of the matrix in case the first file record with

the given characteristics has missing data. The

randomized file is processed and each record is

identified as belonging to one cell of the matrix

(e.g., white, age 25-29, currently married). The

item to be imputed is checked: If it is blank—

not applicable (e.g., not married before), it is

ignored; if it has a missing data code, the code in

the matrix is placed in the record. If it has an

acceptable code, that code replaces the code

already in the matrix, and it remains in the

matrix until another record with the same

characteristics and a known code is encountered.

This insures that the probability of a code being

assigned to a record with missing data is the

same as the probability of that code occurring

among records with the same characteristics but

with known data.

For imputation from a sorted file, the

records are first sorted by selected characteristics (e.g., marital status, race, and age) so that

the first group of records would be currently

married, black women aged 15-19, the second

group would be currently married black women

aged 20-24, etc. An initial value is assigned for

the item to be imputed–e.g., 4 (tubal ligation)

for type of sterilization-and for any item

dependent on the item to be imputed–e.g., 9

(not ascertained) as to whether the operation

was for contraceptive reasons. The ordered file is

processed and each record is checked. If the

item to be imputed is bknk—not applicable, it is

ignored; if it has a known code, it and its

dependent items would replace the existing set

of values; if it has a missing data code, it and its

dependent items wocdd be changed to the preset

values just stated. This procedure insures that

the imputed code is reasonable for the ordering

characteristics and that the probability of assignment is the same as in the population in general.

There will be some bias, however, as the

boundaries between groups are crossed.

Where sampIing error =ffects the precision of

survey estimates, nonsampling error introduces

bias. Imputation procedures reduce this bias to

the extent that the assumptions about the

relations between respondent and nonrespondent characteristics are true. But the amount of

remaining bias, if any, cannot be measured.

Therefore, stringent quality control procedures

were introduced at every stage of the survey,

including the check on completeness of the

household listing mentioned earlier, the extensive training and practice of interviewed, field

observations of interviewed, field editing of

questionnaires, short verification interviews with

a subsample of respondents and missed households, verification of coding and editing, an

independent recode of a sample of questionnaires by NCHS, keypunch verification, and an

extensive computer “cleaning” to check for

impermissible codes, missing data, and response

inconsistencies. One source of bias that can be

evaluated through speciaI studies but cannot be

controlled is respondent error, whether deliberate or unwitting. In this as in other surveys,

the data are subject to problems of accurate

recall and of the stability of respondents’ views

from one time to the next.

Standardization. –The overall rate at which

an event occurs in a population depends on the

distribution of its members in different categories (its “composition”), and the rates at

which the event occurs in each category (its

“category-specific rates”). For instance, the

overall birth rate of a population depends on its

age composition and age-specific birth rates. A

difference between the overall rates of two

populations may result from differences in their

compositions, differences in their categoryspecific rates, or some combination of both; ~for

instance, if the birth rate of a population is

higher than that of another, it may be because

its population is more concentrated in the young

ages which have high birth rates, or because its

birth rates are higher at all ages, or both.

41
Often interest focuses on differences in

rates, not differences in composition, so statistics are needed that are unaffected by differences in composition. The category-specific

rates, such as the age-specific birth rate, have

such characteristics but they pertain only- to

particular categories, whereas it is often desired

to have a single statistic that pertains to the

whole population. A variety of techniques has

been developed to produce overall rates for

populations that are unaffected, or relatively

unaffected, by population composition; they

may be referred to collectively as techniques of

“standardization.” Although the several techniques differ in significant details, they have

a common strategy: Assume the populations

being compared have the same “standard” composition, apply the category-specific rates of

each population to the numbers in each category

of the standard population, sum the numbers of

events that would have occurred in each population under these assumptions, and divide by the

total number in the standard population to

arrive at a standardized overall rate. The standardized rate is interpreted as the rate that each

population would have if its composition were

that of the standard population. It is an artificial

rate that corresponds to no real rate, but it

makes possible interpopulation rate comparisons

that are unaffected by differences in compositions.

The Multiple Classification Analysis (MCA)

technique used in this report is analogous to

standardization just described in that it adjusts

rates (through multiple regression) for differences in composition. This procedure was developed at the University of Michigan, and is

now widely available as a part of many computer software packages. MCA computes standardized rates for subpopulations, using the total

population as the standard. The MCA-standardized rate, like any standardized rate, may be

interpreted as the overall rate which the subpopulation would have if it had its own categoryspecific rates, but the composition of the total

population. Because all MCA-standardized rates

in a table use the same total population as standard, comparisons between them are unaffected

by differences in composition. It is not appropriate, however, to compare MCA-standardized

rates from different tables in this report.

The adjusted percents shown in each table

have been standardized for all other variables

shown in the same table, and, where indicated,

by religious denomination and religious participation as well. The categories of religion used in

the standardization were: Catholic, Baptist,

Lutheran, Fundamentalist, other Protestant

denominations, and other and Jewish. The categories of religious participation were: weekly

attendance at religious services, once a month or

more, occasionally, never, refused an answer,

and no religion. A further discussion of the

definitions of these variables is found in

appendix II. For the employment variables

considered, there were few significant differences between groups of women classified by

religious denomination and religious participation.

In Multiple Classification Analysis, as in

other techniques of standardization, it is

assumed that the effect of one variable on a

second is the same for all values of any third (or

fourth, or fifth, etc.) variable included in the

analysis. (In technical terms, it is assumed that

the effects are “additive.”) In fact, the effect of

one variable on a second is sometimes different

for different values of a third variable. (In

technical terms, there are “interactions” among

the variables.) In such cases, interpretations

based on assumptions of equal effects may be

misleading; that possibility is often outweighed,

however, by. the gain in interpretive insight

derived from standardizing for one or more

variables simultaneously.

The relative standard errors of MCA-standardized percents are estimated to be approximately equal to the relative standard errors of

unadjusted percents, so the same tables and

charts of standard errors may be used.

The Open Interval Problem

For all intervals of time not necessarily

completed before the date of interview (all

except the interval before marriage), some

strategy must be employed to avoid a downward

bias in the estimation of the experience of the

more recent cohorts when intercohort comparisons are being made. For example, for women

married only a few years before interview,

42
women who have already had a first birth

represent those with the shortest intervals and

thus the least opportunity to work before their

first birth. Among women of the same marriage

cohort who wiIl eventually have a first birth,

some who have not yet worked since marriage

will do so before ti,eir first birth.

Two strategies are employed to minimize the

potential bias from open intervals. First, labor

force participation levels are not considered for

the most recent cohorts in which the proportion

of closed intervals of aJl intended intervals is

quite low. Thus, although we can examine

premaritzd employment for the 1970-73 marriage cohorts, the series for first-birth intervals

necessarily terminates in 1969, and that for

second-birth intervals terminates in 1967.

Eighty-seven percent of the 1965-69 cohort

intending a first birth were at first or higher

parity and 72 percent of the 1965-67 cohort

intending a second birth were at second or

higher parity.

The second strategy is to include the open

interval experience of the remaining women who

intend to close the interval in question. Since

the previous rule necesszu-iIylimits such women

to those with longer intervak, any remaining

underestimate of their employment experience

should be minimal. Thus, included in the

measure of “ever worked” for a given interval is

the experience since the beginning of that

interval of women who intend to close it. For

example, the measure of employment before the

first birth includes in the numerator zero-ptity

women who intend to have a child and who have

worked since marriage; the denominator

incIudes all zero-parity women who intend to

have a child.

000
APPENDIX II

DEFINITION OF TERMS

Age.–Age of women at different events in

their lives is classified according to the last

completed year or age at last birthday. Age is

generally calculated by subtracting the reported

date (month and year) of birth from the

reported date of the event for which age is being

calculated. In some instances, the month of an

event was unreported and age was then calculated using the years only. In still other instances, the respondent did not recall a given

date but did recall her age at the time of the

event and-reported this directly. ,

Age of the respondent at the interview

(current age) was known for every case, since

this was a sampling criterion. However, for other

events (such as marriage, the birth of a child, or

divorce), the date may not have been completely

reported or neither date nor age at the* event

may have been recorded. In these cases, age was

imputed by imputing a year in which the event

was presumed to have occurred. These imputations were then checked for consistency with

the dates and ages reported at other related

events.

Race. –Women are classified as white, black,

or “other races” according to the interviewer’s

observations at the time of interview. Agreement

between this classification and the respondent’s

own reports of ethnic origin, also obtained in

the interview, was very high; for instance, of

those classified as “black” by interviewer

observation, 100 percent reported their ethnic

origin as at least partly “black, African, or

Negro t’ and of those who reported their ethnic

origin as “black, African, or Negro,” 96 percent

were classified as “black” by interviewer observation. Race was imputed for 10 cases.

Ethnicity.–Information about ethnic origins

was obtained for the woman and her husband by

asking, “What is your (his) origin or descent?”

Persons were classified as being of Hispanic

origin if any of the following responses were

given: Mexicano, Chicano, Mexican American,

Puerto Rican, Cuban, Hispano, or any other

Spanish origin or descent. Persons who did not

give any of those responses were classified as

being not of Hispanic origin. Persons may have

more than one origin or descent, and multiple

responses to the questions were recorded. However, any of the responses listed above :resulted

in classification of the person as being of

Hispanic origin, regardless of any other

responses that may have accompanied it. It

should be noted that in this report the classifications of race and ethnicity are independent;

each ethnic category may include persons of all

races, and each racial category may include

persons of all ethnic groups. Etlulicity was

reported for more than 99 percent of respondents and husbands.

Rega”on of residence. –Data are classified by

region of residence into the four major Census

regions: Northeast; North Central, South, and

West. Sample size very greatly restricts the

possibility of meaningful analyses by social

characteristics among smaller geographic divisions. The areas comprising these four major

geographic regions are:

Geogaphic regi”on and

division States included

Northeast

New England ...........Maine. New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut

44
Middle Atlantic .......New York, New .lerNorth Central

East North Central

West North Central

sey, Pennsylvania

...Ohio. Indiana, IIIinois,

Michigan, Wisconsin

..Minnesota, Iowa, Missouri, North Dakota,

South Dakota, Nebraska, Kansas

south

South Atlantic .........Delaware. Maryland,

District of Columbia,

Virginia, West Virginia, North Carolina, South CaroIina,

Georgia, Florida

East South Central ...Kentucky. Tennessee,

Alabama, Mississippi

West South CentraI ..Arkansas, Louisiana,

Oklahoma, Texas

West

Mountain .................Montana. Idaho, Wyoming, Colorado,

New Mexico, Arizona,

Utah, Nevada

Pacific ......................Washing-ton. Oregon,

AIaska, California,

Hawaii

Metropolitan-ra onmetropolitan residence.–

The population residing in standard metropolitan statistical areas (SMSA’S) constitutes the

metropolitan population. Except in New

England, an SMSA is a county or group of

contiguous counties that contains at least one

city of 50,000 inhabitants or more, or %vin

cities” with a combined population of at least

50,000. In addition to the county or counties

containing such a city or cities, contiguous

counties are included in an SMSA if, according

to certain criteria, they are essentiality metropolitan in character and are socially and economically integrated with the central county. In New

England, SMSA’S consist of towns and cities,

rather than counties. The metropolitan population in this report is based on SMSA’S as defined

in the 1970 census and does not include any

subsequent additions or changes. For a detailed

discussion see the Bureau of the Budget publication, Standard Metropolitan Statistical Areas:

1967.9

Man”tal status. –Marital status was a criterion

of sample selection. The NSFG sampled women

who were currently married at the time of

interview, had ever been married, or had never

been married but had offspring (i.e., children

born to them) in the household. Current marital

status was recorded in seven categories in response to the question, “Is (PERSON) now

married, widowed, divorced or annulled, separated, or has he/she never been married?” The

seven categories in which answers were recorded

were: married, informal union, widowed,

divorced or annulled, separated, single with own

children, and never married. Women in the k.st

category were not eligible for the survey.

Married women include those, legaIIy or

formally married, whose husbands are living in

the household or are temporarily absent on

business, ihess, vacation, etc. and those who are

inforndy married or “living together” with a

male partner whose usual residence is the same

household. Women currently in informal unions

were reported separately but me too few to be

separately classified for analytical purposes.

Information on informal unions was obtained

only if volunteered by the respondent in the

course of listing household members and their

relationship to the head of the household.

Divorced women include those legally separated from their former spouses by a legal decree

of divorce or annulment and free to remarry.

AIthough those legally separated but without

freedom to remarry belong in the later category

of separated, there was no direct question in the

interview to establish the issue of freedom to

remarry, with certainty. The term “divorce” is

presumed to refer most generally to “absolute”

decrees.

Widowed women are those previously

married women whose most recent spouses are

deceased.

Separated women are those legally or informality separated from their former spouses.

Included here would be cases of desertion,

NOTE: A list of references follows the text.

45
informal separation by mutual agreement, and

legal separations in which the partners are not

free to remarry.

Single with own children is a category of

women who have begun their childbearing and

have never been married. However, some of

these women were probably missed in the survey

because this category was not identified by a

direct question. These are single women who

have one or more children born to them and

living with them in the household. Single women

who gave a child up for adoption or who board

the child elsewhere, and those who have not had

a live birth are not included in the survey.

Marrz”age cohort.–A group of women who

were first married in a specified calend~ period

constitutes a marriage cohort. Because the information for classifying women in marriage cohorts comes from a sample at one point in time,

the sample of all women who married in a

specific period may be biased. Women who were

married in a specific period but who were

outside the ages included in the sample, 15

through 44 years, would not be represented in

the marriage cohorts constructed from these

data. This bias is negligible for recent cohorts,

but is significant for earlier cohorts; in early

cohorts, many women who ‘were of relatively

advanced age at the time of their marriage were

past age 45 at the time of interview, and are not

represented in the sample. The effect of their

omission is to overrepresent early-marrying

women in the early cohorts constructed from

the sample data. For that reason, marriage

cohorts earlier than 1955 are not considered in

this report.

Employment in life-cycle stages.–ln addition to her current employment status, respondents were asked: “Did you ever work for pay?”

in various, specified earlier periods as appropriate: before first marriage, since first marriage, between marriage and first birth, between

first and second birth, between second and third

bith, and between the third and last birth.

Within these periods, women were classified as

employed if they worked for pay and not

employed if they did not. The rate of nonresponse to these questions was low, its maximum

being for questions about employment between

the births of the third and the last child: Employment status was not ascertained for 3

percent of women asked about the period, and

duration of employment was not ascertained for

9 percent. Missing values were imputed.

Employment before and after last birth.–T.o

determine the relationship between pregnancy,

childbirth, and employment, women who had

had a live birth were asked: “How long before

the birth of your last child did you stop

working?” and “In what month and year did

you begin to work after your (last) child was

born?” Women who reported they stopped work

9 months or less before the last birth were

classified as having been employed during that

pregnancy; if they reported stopping 3 mo?t%s

or less before the birth, they were classified as

having worked in the last trimester of the

pregnancy. These classifications assume a

9-month pregnancy before the last birth, and,

therefore, may produce erroneous classifications J

of women whose pregnancies were significantly

longer or shorter; in the aggregate, however,

these errors would tend to cancel one another

out.

Responses to the second question, about

starting work after the last birth, were used in

conjunction with the reported date of the last

birth to compute the number of months between the birth and subseqiient employment.

About 7 percent of women to whom these

questions applied could not be classified because

of missing, data; values were imputed for those

cases.

Occupation.–Ociupation was determined by

asking women: “What (is/was) your (main)

occupation? That is, what (is/was) your job

called? What (are/were) your most important

activities or duties? What kind of place (do/did)

you work for? What do they make or do?” The

answers to those questions were recorded verbatim and used by coders to find the most

appropriate standard job title in the 19’70 U. S.’

Census occupation classification. If the responses indicated more than one occupation, the

primary occupation was coded. If none was

primary, the first-mentioned occupation was

coded. Although the classification used was very

detailed, occupations have been grouped into

major categori& for

practice of the U.S.

this report, according to the

Bureau of the Census. For a

46
more detailed discussion, see the Department of

Commerce publication, 1970 Census of Populatt”on, Detailed Characteristics, U.S. Summa~. ~O

Income.–To determine the husband’s income, currently married women whose husbands

had worked in the past 12 months were asked:

“In the past 12 months–that is since (MONTH)

1972–what did your husband earn in wages,

salary, or in his own business or profession?”

For the 44 percent of women who did not know

their husband’s income or who refused to

answer the question the interviewer continued:

“Here is a card showing amounts of weekly

and yearly incomes. Next to each amount is a

letter. Would you tell me what letter represents

the income before taxes and other deductions

that your husband earned in wages, salary or in

his own business or profession during the past

12 months.”

Weeldy incomes were converted to annual

amounts. Husband’s income was determined for

all but 7 percent of the women asked these

questions, and values were imputed for them.

Since the questions ask only about wages, salary,

and business and professional income, this measure of income does not include other forms of

income, such as unemployment compensation,

social security income, welfare payments, and

dividends. Information was obtained on these

other sources of income by other questions, but

was not used for this measure of income.

Education. –Education is classified according

to the highest grade or year of regular school or

college that was completed. Determination of

the highest year of reguhr school or college

completed by the respondent is based on responses to a series of questions concerning (a)

the last grade or year of school attended, (b)

whether or not that grade was completed, (c)

whether any other schooling of a vocational or

generally nonacademic type was obtained, and

(d) whether or not such other schooling was

included in the years of regular school or college

reported in (a). Information on education was

reported almost completely: OnIy about 1 percent of the data was imputed.

NOTE: A list of references follows the text.

Education at marriage.-h addition to the

questions about education at the time of the

interview, women were asked: “What was the

highest grade or year of regular school (or

college) you had completed at the time of your

(first) marriage?” Although the foIIowup questions that asked about current educational

attainment were not asked about education at

marriage, responses were coded in the same

categories. Response to this item was nearly

complete, with less than 1 percent of values

being imputed.

Reli#”on. –Women were classified by religion

in response to the question: “Are you Protestant, Roman CathoIic, Jewish, or something

else?” In addition to the three major religious

groupings, two other categories-other and none–

were used. Since the category of Protestant

includes numerous individual denominations,

these respondents were further asked to identify

the denomination to which they belonged.

Those who answered “other” to the original

question and then named a Protestant denomination were included with their own groups.

Although specific denominational names were

obtained and recorded, the numbers of cases for

most denominations were too few to produce

reliable estimates, so they have been combined

in larger categories. Data on religious denominations were reported for all but 26 respondent

cases, or more than 99 percent, and these few

cases were imputed.

Reli@-ous participation. –Roman Catholic

women were asked: “How often do you receive

communion?” Women in other religious groups

were asked: “About how often do -you usually

attend religious services?” For only 6.9 women,

less than 1 percent , uncodable answers were

obtained, and values were imputed for them.

For the purposes of this report, it was assumed

that the question asked Catholic women, and

the question asked other women, were enough

alike to be regarded as measuring the broadly

equiwdent aspects of behavior, so there is one

religious participation measure for all religious

groups.

Parz”ty.-Parity is the fact or condition of

having borne children and is specified in terms

of the number of live births a woman has had. A

woman with no live births is referred to in

47
obstetrical and demographic terminology as

“nulliparous” or of “zero parity”; a woman with

one live birth is referred to as “primaparous” or

of “first parity, ” and so forth. A woman’s parity

in these surveys is determined from the qhestions: “Have you given bitth to a baby at any

time?” and, if yes, “Altogether, how many

babies have you given birth to, including any

who died very young?” The accuracy of this

information is further verified by obtaining

detailed data about each pregnancy and additional information on those pregnancies ending

in live issue. A complete pregnancy history was a

primary focus of the survey and information on

the number of live births and number of

pregnancies was obtained for 10g, percent of the

respondents.

Timing of first birth.–The first live birth is

classified as occurring before or after the first or

only marriage. If the first birth preceded

marriage, a woman is classified as having had a

premarital birth.

Timing of first pregnancy. -If a woman’s

first pregnancy ended before marriage, or less

than 7 months after marriage, she is classified as

having had a premarital pregnancy.

Additional births expected.–The number of

children a woman expects to give birth to in the

future, including current pregnancy (if applicable) is termed, “additional births expected. ”

Women who were sterile or married to sterile

men were classified as expecting zero additional

births. Those physically able to have births were

asked whether they and their husbands intended

to have any babies in the future and, if so, how

many. Women who did not know whether they

intended any future births, or did not know a

particular number they intended to have, were

asked for the smallest and largest numbers they

expected to have. Women who reported a

particular number of children they intended to

have were asked how sure they were about

having specifically that number. Those uncertain

of having that specific number were also asked

for the Imaximum and minimum numbers they

expected to have.

For each woman, there is a maximum,

minimum, and central number of additional

births expected. If a woman reported a specific

number she intended to have, that was considered the central number she expected. If she

was sure about it, that was also the minimum

and maximum number she expected. For a

woman who was not sure of having just her

intended number, the smallest and largest numbers she expected were her minimum and

maximum numbers, respectively. For a womzm

who did not report any specific number of

intended future births, the average of the smallest and the largest numbers became her central

expected number. In this report, discussion of

additional births expected refers to the central

number unless specifically identified otherwise.

Since this datum was generated from basic

interview data for which missing data had

already been imputed, there were no missing

data for additional births expected. It should be

noted, however, that imputed data were used in

generating additional births expected for about

6 percent of the cases.

Last child intended. –If a woman had one or

more live births, and she was sterile or intended ‘

to have no more children, then her most

recently born child was the last child intended.

48

000

f? U.S. GOVERNMENT PRINTING OFFICE, 19S0 C-31 1-240 (40)
e

APPENDIX Ill

ITEMS ON QUESTIONNAIRE RELATING TO EMPLOYMENT OF MOTHERS

IN INTERVALS BEFORE, BETWEE-N, AND AFTER BIRTHS

A. IF YES: Altogether, how long did you work bO 61

before you were (first) married? (YEARS)

Less than one year 00

143, IF RHAS NEVER HAD ALIVE BIRTH, SKIP TO Q. 148 (SEE RECALL CHART@);

OTHERWISE CONTINUE.

Between the time of your (first) marriage Yes . . . (ASKA) . 1 10

and the birth of your (first) child, did

you ever work for pay?

No. . . . . . . . .2

A. Altogether,.how long did you work between 11 12

the time of your (first) marriage and the (YEAR)

birth of your (first) child? Less than one year . 00

l!!!, :~Tg;~H;::sy:o;::u;IRTH’ SKIP TO INTERV. CHECK ITEM BELOW (SEE RECALL

.

Between the birth of your first child and Yes . . . (ASKA) . 1 13

the birth of your second child, did you

ever work for pay?

No. . .: . . . . .2

A. Altogether, how long did you work between 14 1s

the birth of your first child and the (YEARS)

birth of your second child? Less than one year . 00

14.5,IF RHAS HAD ONLY TWO LIVE BIRTHS, SKIP TO INTERV. CHECK ITEM BELOW (SEE RECALL

CHART ~; OTHERWISE CONTINUE.

Between the birth of your second child and Yes . . . (ASKA) . 1 16

the birth of your third child, did you ever No. . . . . . , . .2

work for pay?

A. Altogether, how long did You work between 17 18

the birth of your second child and the (YEARS)

birth of your third child? Less than one year . 00
1~~, IF RI-M HAD ONLY THREE LIVE BIRTHS, SKIP TO INTERV. CHECK IT13fBELOW (SEE RECALL

CHART @j); OTHERWISE CONTINUE.

Between the birth of your third Yes .,. ~ASK A) . 1 19

child and the birth of your last

child, did you ever work for pay?

NO (SKIP TO Q. 149). 2

A. Altogether, how long did you

work between the birth of your (YEARS)

20 21

third child,and the birth of Less than one year . 00

your last child?

INTERVIEWER CHECK ITEM

MORE THAN ONE

LIVE BIRTH: DID R WORK BETWEEN BIRTH OF NEXT TO LAST CHILD AND LAST CHILD?

Yes . . . . CHECKD& CONTINUE WITH Q. 147.

No. . . . . CHECKm& SKIP TO Q. 149.

Don’t know . CHECK~ CONTINUE WITH Q. 147.

ONLY ONE

LIVE BIRTH: DID R WORK BEFORE BIRTH OF CHILD?

Yes . . . . CHECKO & CONTINUE WITH Q. 147.

No. . . . . CHECK m& SKIP TO Q. 149.

147, How long before the birth of your (last) child did you~ working?

Less than one month (SKIP TO Q. 149) . 00 22 23

Number of months (SKIP TO Q. 149)

One year or more (SKIP TO Q. 149) . . 12

1~~, Since you were (first) married, Yes (ASK A) . ...1

have you ever worked for pay?

24

No. . . . . . . . .2

A. Altogether, how long have

you worked since your (YEAR)

25 26

(first) marriage? Less than one year . 00

~, IF NO LIVj3BIRTHS, sKIp TO Q. 157 (SEE REcmL cH,ART @); OTHERWISE CONTINUE.

Have you worked for pay at any time since your (last) child was born?

Yes .1 41

No . &I; ~0 4.”1{7~ . 2

~, Altogether, how long have you worked Less than one year . . . . 00 42 43

since the birth of your (last)child? Number of years . .

~, Inwhatmonth andyeardid you begin mm 1$4 47

to work after your (last) child was

born? (MONTH) (yEAR)
Series 1.

Series 2.

Series 3.

Series 4.

Series 10.

.Sf’rrc\ /2.

.Vfries t ;,

Swie.s t4,

Series 20.

Series 21.

Series 22.

.%7ies 23.

.

VITAL AND HEALTH STATISTICS Series

Programs and Collection Procedures.–Reports which describe the general programs of the National

Center for Health Statistics and its offices and divisions and data collection methods used and include

definitions and other material necessary for understanding the data.

Data Ezmluatiorr and .Methods Research. –Studies of new statistical methodology including experimental tests of new survey methods, studies of vital statistics collection methods, new analytical

techniques, objective evaluations of reliability of coIlected data, and contributions to statistical theory.

Analytical Studies. –Reports presenting analytical or interpretive studies based on vital and health

statistics, carrying the analysis further than the expository types of reports in the other series.

Documents tzrzd Committee Reports. –Final reports of major committees concerned with vital and

health statistics and documents such as recommended model vital registration laws and revised birth

and death certificates.

Data Fro m the Health lnterzreu Survey. – Statistlm on illness, accidental injuries, disability, use of

hospital, medical, dental, and other services, and other health-related topics, all based on data collected

in a continuing national household interview survey.

l)ata b TOm the Health Examination Survey and the Health and Nutrition Examirwtion Swoey. Data

from direct examination, testing, and measurement of national samples of the civilian noninstitutionalized population provide the basis for two types of reports: (I) estimates of the medically defined

prevalence of specific diseases in the United States and the distributions of the population with respect

(o physical, physiological, and psychological characteristics and ( 2) analysis of relationships among the

various measurements without reference to an explicit finite universe of persons.

L)uta From th< lnstitutionaliz~d Population Survey s.--Disct)ntinued effective 1975. Future reports from

these surveys will he in Series 13.

Data on Health Resources (’utilization. --Statistics on the utilization of health manpower an[i facilities

providing long-term care, ambulatory care, hospital care, and family planning services,

Data on Health Resources: .Wurzpo uwr and Futilities. –Statistics on the numbers, geographic distri

bution. and characteristics of health resources including physicians, dentists, nurses, other health

occupations, hospitals+ nursing homes, and outpatient facilities.

Data on Morta/it},. –\’arious statistics on mortality other than as included in regular annual or monthly

reports. Special analyses by cause of death, age, and other demographic variables; geographic and time

series analyses; and statistics on characteristics of deaths not available from the vital records based on

sample surveys of those records.

Data o n .Vatality, .}larriugc, u n(l [Jiz)orc,. I:,wi[>us statistics on natality, marriage, and divorce othex

than as included in regular mnual or monthlv reports. Special analyses by demographic varlahles;

geographic and time series ,Iti.IIJ ses; stu(fies {If fertility; and statistics on {characteristics o} births not

available from the vital records based on sample surveys of those records.

Data From the Notional .Wortality and .Vatalit~ Stir? ey.c. Discontinued effective 1975 kuturr rrports

from these sample surveys ljased on vital re(t]rds \viil be included in Series 20 and 21, respective.,

Data From the National Sur:ev of Family Growth. Statistics on fertility, family formation and dissolution, family planning, and related maternal and infant health topics derived from a biennial survey

of a nationwide probability sample of ever-married women 15-44 years of age.

For a list of tit{es of reports published in these series, wr]te to: Scientific and Technical Information Branch

National Center for Health Statistics

Public Health Service

I{vattsville, hid. 20782

/