Data from the


NATIONAL VITAL STATISTICS SYSTEM


differentials in 

Expectationof 

AdditionalChildren 

AmongMothers of 

legitimate live Births 

UnitedStates-1964-1966 

Statistics on differentials inthe proportion of mothers expecting 

to have additional children and in the average number of additional children expected, according to selected demographic and 

socioeconomic characteristics. Based on data collected by a 

quest ionnaire mailed to mothers for a sample selected from records of births in 1964, 1965, and 1966 which were filed with 

the hJationa 1 Center for Hea Ith Statistics. 

DHEW Publication No. (HSM)-72-1044 

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

Public Health Service 

Health Services and Mental Health Administration 

National Center for Health Statistics 

Rockville, Md. February 1972 

Series 22 

Number 13 
Vital and Health Statistics-Series 22-No. 13 

For sale by the Superintendent of Docnments, U.S. Government Printing Office. washiwton, D.C. Z040S 

Price 55cents domestic postpaid or 40 cents GPO Bookstore 
NATIONAL CENTER FOR HEALTH STATISTICS 

THEODORE D. WOOLSEY, Director 

PHILIP S. LAWRENCE, SC.D,, Associate Director


OSWALD K. SAGEN, Ph. D., Assistant Director-for Health Statistics Development


WALT R. SIMMONS, M.A., Assistant Director for Research and Scientific Development


JAMES E. KELLY, D.D.S., Dental Advisor


EDWARD E. MINTY, Executive Officer 

ALICE HAYWOOD, Information Officer 

DIVISION OF VITAL STATISTICS 

ROBERT A. ISRAEL, M.S., Director


JOHN E. PATTERSON, Assistant Dire,ctor for Demographic Affairs


ARNE B. NELSON, M.A., Chief Vital Records Survey Branch


Vital and Health Statistics-Series 22-No. 13 

DHEW Publication No. (HSM) 72-1044


Library of Congress Catalog Card Number 79-610284

CONTENTS 

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


Sources and Limitations of the Data . . . . . . . . . . . . . . . . . . . . . .


Nature of the Population . . . . . . . . . . . . . . . . . . . . . . . . . . . .


The Expectation of Additional Children . . . . . . . . . . . . . . . . . . . .


Number of Living Children . . . . . . . . . . . . . . . . . . . . . . . . .


FetaJand Infant Deaths . . . . . . . . . . . . . . . . . . . . . . . . . . .


Interval Between Last Two Children and Sex of Children . . . . . . . . . .


Age of Mother, Interval Since First Marriage, and Age at


First Marriage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Family Income . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Mother’s Employment During Pregnancy . . . . . . . . . . . . . . . . . .


Education of Mother and Father . . . . . . . . . . . . . . . . . . . . . .


Race of Mother . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Geographic Region and Metropolitan Status of Residence . . . . . . . . .


Summary and Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . .


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


Listof Detailed Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Appendix I. Technical Notes on Methods . . . . . . . . . . . . . . . . . .


Background of This Report . . . . . . . . . . . . . . . . . . . . . . . . .


Sample Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


The Birth Certificate and Questionnaire . . . . . . . . . . . . . . . . . . .


Collection of Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Processing of Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Nonresponse and Imputation for Missing Data . . . . . . . . . . . . . . .


Estimation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


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


Standardization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Rounding of Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . .


1 

1 

3 

5 

5 

6 

6 

7 

9 

10 

10 

11 

12 

13 

16 

17 

35 

35 

35 

36 

37 

37 

38 

39 

41 

42 

43 

... 

Ill 
---

-------------------------------

----------------------------------------------

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CONTENTS–Con. 

Page 

Appendix II. Certain Terms Used in This Report . . . . . . . . . . . . . . . 44 

Information From the Certificate of Live Birth . . . . . . . . I. . . . . . . 44 

Information From the Questionnaire . . . . . . . . . . . . . . . . . . . . 44 

Appendix III. Source Forms... . . . . . . . . . . . . . . . . . . . . ...46 

Certificate of Live Birth . . . . . . . . . . . . . . . . . . . . . . . . . . . 46 

Informant Questionnaire . . . . . . . . . . . . . . . . . . . . . . . . ..47 

SYMBOLS 

Data not available---------------------------------------

Category not applicable 

Qtiantity zero 

Quantity more than Obut less than 0.05 -----

Figure does not meet standards of 

reliability or precision 

iv 

. . . 

. 

0.0 

* 
DIFFERENTIALS IN 

EXPECTATION OF ADDITIONAL CHILDREN 

AMONG MOTHERS OF LEGITIMATE LIVE BIRTHS 

Mary Grace Kovar, Divkion of Vital Statistics 

INTRODUCTION 

There have been a number of studies in the 

past few years designed to predict future fertility by asking women how many children they 

expect, intend, or desire to have. These studies 

have been exhaustively analyzed elsewhere and 

will not be discussed here. 

The present study, which is based on a sample 

of birth certificates, was designed to furnish 

information on two points only. First, given that 

a woman has recently given birth to a child, 

what factors obtained either from the birth 

certificate or from a questionnaire mailed to the 

mother might affect her expectation of having 

additional children? Second, if these factors do 

have an effect on the mother’s expectations, is it 

a consistent one regardless of the number of 

children she already has? Presumably the mothers with two living children or more will expect 

to have fewer additional children than the 

mothers with one child since they have already 

completed more of their family. The question 

then is whether the socioeconomic and demographic factors that influence the expectation of 

additional children among mothers of one child 

exert the same influence among mothers with 

two, three, or more children. Data from the 

196466 National Natality Survey (NNS) show 

that while the influence of demographic factors 

such as age and interval since first marriage 

seems to be consistent regardless of the number 

of children the mother already has, no such 

consistency is apparent for socioeconomic factors such as education and family income. 

SOURCES AND LIMITATION OF THE DATA 

The sample for the 1964-66 National Natality 

Survey was drawn from the file of birth certificates for children born in the United States 

during those 3 years. From the sample of all 

births, those which were recorded as or inferred 

to be legitimate were selected for the survey. 

Because the sample was drawn from the birth 

certificates in such a manner that each birth 

rather than each mother had a known probability of being selected, the estimates given here 

are technicality estimates of births rather than 

estimates of mothers. However, for ease and 

clarity in writing, the terms “married women” 

and “mothers” are used rather than “legitimate 

live births.” 

The sample was selected in advance from all 

the birth certificates expected in a given year so 

that as the monthly shipments of certificates 

were received by the National Center for Health 

Statistics (NCHS), those selected for the survey 

could be copied without waiting for the entire 

shipment to be processed. The first attempt to 

contact the mother was made as soon as possible 

after the birth, but because of registration and 

survey procedures the first contact was usually 

not made until the sampIe child was 3 to 6 

months old. In a few cases where the birth 

certificate was filed late or the mother proved 

difficult to locate, no contact was made until 

the child was nearly a year old. 

It is not known precisely how long after the 

birth of the child the mother reported her 

expectation of additional children. In general, it 

1

was close to 6 months; occasionally it was 

almost a year. 

The survey was conducted primarily by mail. 

To reduce the biases which might be introduced 

because of differential response to a mail survey, 

personal interviews were attempted with those 

women who did not res’pond to the mail survey 

and who were residents of one of the primary 

sampling units designated by the U.S. Bureau of 

the Census. The overall response rate for the 

10,395 cases selected for the survey was 89 

percent. Questionnaire information for the nonrespondents ,was imputed using a matrix based 

on age, color, and live-birth order obtained from 

birth certificate’ information available for both 

respondents and nonrespondents. 

Because the NNS was a mail survey, the 

questionnaire was designed to be as easily 

understood and as unambiguous as possible so 

that the woman could complete it without help. 

The design of the question on expectations was 

apparently successful, at least in that respect, as 

99 percent of the respondents to the questionnaire answered the question on whether they 

expected more children and 96 percent reported 

the number of children expected. Of those who 

did not answer, many wrote marginal comments 

explaining that they did not know. Data for 

those who did not respond to a specific item 

such as number of additional children expected 

were also imputed by a special matrix which 

took advantage of the information which was 

known from other parts of the questionnaire as 

well as that available from the birth certificate. 

The disadvantage of a mail questionnaire is 

that no probing in depth is possible because of 

the necessary restrictions on the design of a mail 

form. It is possible, however, that this disadvantage is offset by the willingness of the women to 

respond to an impersonal questionnaire which 

can be sealed in a preaddressed envelope and 

dropped into the mail rather than to an interviewer. Also, the use of the mail form eliminates 

the possibility of interviewer bias which is 

particularly important as some of the woman’s 

previous fertility might have antedated her 

marriage. No quantitative evidence on these 

points is available from the NNS. Only a 

qualitative judgment based on comments which 

respondents wrote on questionnaires and on a 

small sample of interviews supports this view. 

The number of additional children expected, 

as shown in this report, is more likely to be an 

underestimate than an overestimatee. First, 

women who responded “Definitely no” or 

“Probably no” were not asked how many 

children they expected to have in the future. 

The number of children expected by these 

women was set at zero, even though the mothers 

who responded “Probably no” most likely 

should have had a value greater than zero 

assigned to them. (In the Growth of American 

Families study, for example, certain women 

were assigned a value of 0.3.)1 Second, the rules 

for coding the responses were: If a respondent 

reported a range of one (e.g., two or three) the 

lower number was coded; if she reported a range 

of two (e.g., two or four) the middle number 

was coded. If the average of the range had been 

coded in both cases, 106,000 more children 

would have been added to the total number of 

additional children expected (table A). If the 

upper number of the range had been coded in 

both cases, 221,000 more children would have 

been added to the number of additional children 

expected. Finally, approximately 5 percent of 

the women responded to the question but wrote 

comments on the questionnaire which indicated 

that although they were doing their best to 

answer, they really did not know how many 

more children they expected to have. While it is 

obviously impossible to make quantitative estimates for these women which differ from their 

stated expectation regarding their future childbearing, a qualitative judgment is that for the 

most part they were making minimum estimates. 

They were mostly women who responded “Definitely yes.” They expected to have additional 

children, but found it difficult to predict how 

many additional children they would have. It 

seems likely that the number they gave was the 

number they were relatively firm about. Their 

problem was apparently in predicting how many 

children they might have beyond the minimum 

they were reasonably sure of. 

The number of living children has been used 

in this report rather than the conventional 

live-birth order (or parity) because the question 

used to ascertain expectation of additional 

children was “Do you expect to have more 

children?” not “Do you expect to have more 

births?” and thus the mother’s frame of refer2 
Table A. Average annual number of mothers according to qualifications on Pert two of expectation question, by response to part one: 

United States, 1964.66 National Natality Survey 

Reported qualifications on number 

Number of I of children expected 

mothers 

None Range of one Range of two Don’t know Religion Refusal 

/ 

All responses . . . . . . . . 3,480 3,077 

Total responses“yes” . . . . . . . 1,882 

Definitely “yas” . . . . . . . . 887 710 

Probably “yes” . . . . . . . . . 994 812 

Total responses “no” . . . . . . . . 1,599 

Probably “no” . . . . . . . . . 981 945 

Definitely “no” . . . . . . . . . 618 610 

ence when she answered the auestion was A 

children rather than births. 

The number of living chiklren was defined as 

the number living on the date of the sample 

child’s birth, including the sample child. The 

possible death of a child between that date and 

the time the mother completed the questionnaire may introduce an unknown bias in the 

data. This method of coding was used, however, 

because the 1964-66 NNS was a multipurpose 

survey and other needs for the data required 

such coding. 

There was very little difference in the average 

number of children whether live births or living 

children were used. On the average, the mothers 

in the 19W-66 NNS had 2.84 live births and 

2.78 living children. The differences in expectation according to whether or not the mother had 

had a child who died in infancy before the birth 

of the sample child are shown later in this 

report.. 

NATURE OF THE POPULATION 

The population discussed in this report consists of married women in the United States who 

Number in thousends 

212 9 156 22 3 

125 7 36 8 1 

87 2 83 10 . 

30 3 2 

7 1 

had a live birth in 1964, 1965, or 1966. Because 

they had recently had a child, they were a 

special subset of all married women in the 

childbearing ages who differed from all married 

women in the childbearing ages in several important respects. 

They were younger than all married women 

ages 15-44; 14 percent were under age 20, 36 

percent were aged 20-24; and 26 percent were 

aged 25-29. Altogether, 75 percent were under 

age 30, and only 2 percent were age 40 or older 

(table B). 

In contrast, according to data from the June 

1965 Current Population Survey (CPS) conducted by the Bureau of the Census, only 4 

percent of all currently married women aged 

15-44 were under age 20, 17 percent were aged 

20-24, and 19 percent were aged 25-29. Altogether, 39 percent were under age 30 and 21 

percent were aged 40-44.2 

The women in the NNS had had, on the 

average, 2.84 live births while the married 

women in the CPS had had, on the average, 2.48 

children ever born. One reason for the difference 

in the number of children ever born is, of 

course, the exclusion from the NNS of married 

3 
Table B. Percent distribution of mothers of legitimate births (196446) and of currently married women (June 1965) aged 1544, by 

selected characteristics: United States, 1964-66 National Natality Survey and June 1965 Current Population Survey 

Characteristics 

Age of woman 

All ages 1544 years 

15-19 years . . . . . . , 

20-24 years . . . . . . , 

25-29 years . . . . . . , 

30-34 years . . . . . . , 

35-39 years . . . . . . , 

40-44 years . . . . . . . 

Race of woman 

All races . . . . . 

White . . . . . . . . . . 

Negro . . . . . . . . . . 

All other races . . . . . . 

All regions . . , . 

Northeast . . . . . . . . 

North Cantral . . . . . . 

South . . . . . . . . . . 

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

Metropolitan status 

of residence 

All United States . 

Metropolitan . . . , . . 

Non-metropolitan . . . . 

Number of 

times married 

All married women 

Once . . . . . . . . . . . 

More than once . . . . . 

I Mothers of I Currently 

legitimate married 

births women 

1964%6 NNS June 1965 CPS 

Percent distribution 

. . 100.0 100.0 

. . 13.6 4.0 

. . 36.1 16.7 

. . 25.6 18.6 

. . 14.5 18.9 

. . 7.8 20.9 

. . 2.3 20.9 

. . 100.0 100.0 

. . 86.9 88.8 

. . 11.7 10.2 

. . 1.4 0.9 

. . 100.0 100.0 

. . 23.5 24.3 

. . 28.5 28.0 

. . 31.4 30.9 

. . 16.7 16.7 

. . 100.0 100.0 

. . 64.3 65.5 

. . 35.7 34.5 

. . 100.0 100.0 

. . 92.4 88.6 

. . 7.6 11.4 

Education of woman Percent distribution 

All levels . . . . . . . 

Elementary school . . . . . .


High school, 1-3 years . . . .


4years . . . . .


College, 1-3 years . . . . . .


4 years 

or more . . . . . 

Family income 

All incomes . . . . . . 

Under $3,000 . . . . . . . . 

$3,000-$4,988 . . . . . . . . 

$5,000-$6,999 . . . . . . . . 

$7,000-$8,988 . . . . . . . . 

$10,OOO and over. . . . . . . 

Age at first marriage 

Alleges . . . . . . . . 

Under 18years . . . . . . . 

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

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

22-24 years . . . . . . . . . 

25 years and over. . . . . . . 

Number of children 

born alive 

All children . . . . . . 

No children . . . . . . . . . 

Onechild . . . . . . . . . . 

Two children . . . . . . . . 

Three children . . . . . . . . 

Four children , . . . . . . . 

Five children or more , . . . 

100.0 100,0 

12.2 33.7 

25.0 22.7 

43,7 47,3 

12.2 9.5 

6.9 6.9 

100.0 100.0 

19.8 11.6 

22,4 18.9 

25.5 24,6 

20.6 26.8 

11.7 18.2 

100.0 100.0 ~ 

24.0 21.9 

31.9 29.2 

22.7 22.4 

14.2 16.5 

7.3 10.0 

100.0 100.0 

. . . 13.8 

29.0 17.1 

25.1 25.3 

17.8 19.9 

11.5 11.2 

16.5 12.6 

women who had never had a child. According to 

the CPS, approximate] y 14 percent of ‘the 

married women had never borne a child. If these 

women are excluded, then the average numb er 

of children ever born to women who had had 

one child or more was higher in the CPS than in 

the NNS for all ages 15-44 although probably 

not for age-specific components. The data necessary to make the age-specific comparisons have 

not been tabulated. 

Approximately 63 percent of the women in 

the NNS were at least high school graduates and 

4 
19 percent had completed 1 year or more of 

college. Approximately 64 percent of the 

women in the CPS had graduated from high 

school, but only 16 percent had completed 1 

year or more of college. The median number of 

years of school completed was 12.3 for both 

groups. 

In the NNS the median family income during 

the calendar year before the child 

was born was $5,61 O; approximately 42 percent 

of the families had an income of under $5,000. 

Only 31 percent of the families in the CPS had 

an income of under $5,000. The relatively low 

income for families in the NNS would be expected because the fathers, being young, would 

not yet have reached peak earning power and 

because the presence of small children in the 

home may have prevented many mothers from 

working. Data from the March 1965 CPS show 

that in all husband-wife families where the husband was under 45 years of age, 25 percent of 

the families had incomes under $5,000 in 1964. 

Within this same category, however, 34 percent 

of the families had incomes under $5,000 in 

1964 when all the children were under 6 years of 

age, 24 percent when some of the children were 

under 6 years of age, and only 15 percent when 

all of the children were aged 6-17. Thus the 

incomes ~f the families in the NNS seemed 

comparable with those of all husband-wife families where the husband was under age 45 and all 

the children were under age 6.3 

Approximately 87 percent of the women in 

the NNS were white, 12 percent were Negro, 

and 1 percent were members of other minority 

races. About 64 percent of the women were 

residents of metropolitan areas of the United 

States. Approximately 31 percent of all the 

women and more than 50 percent of the women 

who were members of Negro or other minority 

races were residents of the South. 

Thus the women .in the 1964-66 NNS were 

younger and had had more children than would 

be the case had the sample been drawn from all 

ever-married women. Furthermore, because the 

sample was drawn from women who had recently had a birth, age and number of children 

were closely related. Because both age and 

number of children are closely related to expectations of additional children, the data shown 

here should not be used to make generalizations 

about the total population of married women. 

The tables were designed only to show differentials in expectations among married women 

who were having chihiren during 196466. 

THE EXPECTATION OF 

ADDITIONAL CHILDREN 

Of the estimated annual average 3,480,000 

women who had legitimate live births in the 

United States during 1964-66, approximately 54 

percent expected to have at least one more 

child. Given that they had, on the average, 2.78 

living children at the time they were asked about 

their expectations, they expected to COmP1ete 

their families with 3.73 children. 

Approximately 26 percent of the mothers 

reported that they definitely expected to have 

more children; they expected to have an average 

of 2.10 addh.ional children (table 1). Approximately 29 percent reported that they would 

probably have additional children, with an average of 1.45 additional children. Approximately 

28 percent of the mothers reported that they 

would probably not have any more children, tid 

18 percent reported that they would definitely 

not have any additional children. Thus 46 

percent of the mothers expected to have no 

more children. They had completed their families with the birth of this child. 

Number of Living Children 

The proportion of mothers who expected to 

have more children decreased from 92 percent 

of those who had one living child to 55 percent 

of those who had two, 38 percent of those who 

had three, and 22 percent of those who had four 

children. There was little variation in the proportion who expected to have more children among 

women who had four, five, or six or more living 

children. Among those mothers who expected to 

have more children, approximately two-thirds of 

those with only one chJd definitely expected 

more while one-third or less of those with two 

living children or more were definite. 

The average number of additional children 

expected showed. the same sort of differential 

pattern as the proportion expecting to have 

additional children. The mothers of one living 

child expected to have, on the average, 1.77 

additional childrem, mothers of two children 

expected 0.90 additional children; mothers of 

5 
three children expected 0.55 and mothers of 

four children expected 0.35 additional children. 

Again there was little variation among mothers 

of four, five, or six or more children. 

Among mothers who reported that they 

expected to have additonal children, the differences in the average number expected were not 

as great. On the average, mothers who expected 

additional children expected to have 1.76 more 

children. Mothers of one child expected the 

most—1.93 additional children. Mothers of three 

children expected the fewest—1.44 additional 

children. Mothers of four, five, or six or more 

living children who expected to have additional 

children expected more additional children than 

mothers with only three. 

Regardless of the number of children they 

already had, the mothers who reported that they 

definitely expected to have more expected a 

higher average number of additional children 

(2.10 overall) than those who reported that they 

would probably have more (1.45). Neither of 

these measures appeared to differentiate well 

between classes of women with a specified 

number of children. 

Because the proportion of mothers expecting 

to have additional children and the average 

number of additional children expected by all 

mothers show, the greatest differential, the remainder of the report concentrates on these two 

measures. The average number of additional 

children expected by mothers who expect more 

is also shown in all detailed tables. 

Fetal and Infant Deaths 

The number of living children a woman has 

depends on the number of times she has been 

pregnant, the number of children born alive, and 

the number who survive after birth. In other 

words, the number of living children depends 

upon whether any pregnancies failed to result in 

a live birth and whether any of the children born 

alive died after birth. 

The mothers in the NNS were asked whether 

they had ever had a miscarriage or a stillbirth 

and, if so, how many. They were also asked if 

any of their children had died and, if so, the 

date of death. These questions were used to 

develop a measure of fetal deaths (reported 

miscarriages plus stillbirths) and infant deaths 

(deaths of children under 1 year of age). 

The death of a child in infancy (under 1 year) 

appeared to have more influence on a mother’s 

stated expectations of having additional children 

than a fetal death (tables 2 and 3). The 

proportion of mothers expecting to have additional children was lower among those mothers 

reporting one infant death or more than among 

those whose chilcken had all survived their first 

year. Except among mothers with one child, 

the proportion expecting to have additional 

children was approximately the same regardless 

of whether the mother had ever experienced a 

fetal death. 

These data on infant deaths can be used to 

obtain an approximate answer to the question of 

whether women will try to replace a child lost in 

infancy. Because the majority of the mothers 

with one infant death or more had only one 

such death, the mothers in a specified livingchild category who had one infant death or 

more have had the same number of live births as 

the mothers in the next higher category who had 

no infant deaths. Thus the expectations of the 

39,000 mothers of two living children who had 

one infant death or more would be comparable 

to those of the 583,000 mothers of three living 

chiklren who had no infant deaths. In all except 

one case, such a comparison shows that if the 

mothers had been classified by number of 

children born alive, a higher proportion of those 

who lost a child in infancy than of those who 

did not lose a child expected to have additional 

children. 

Interval Between Last Two Children and Sex of 

Children 

Among mothers of two or three children, 

there was an inverse relationship between the 

proportion expecting to have additional children 

or the average number expected and the interval 

between the birth of the preceding child and the 

sample child. Among mothers of four or five 

children, “expectation of additional children was 

highest when the preceding child had been born 

12-23 months before the sample child. However, 

the inverse relationship held for all longer 

intervals (table 4). 

6 
At least part of the decrease in the proportion 

expecting additional children could be explained 

by the fact that longer birth intervals denote 

older mothers, since there is a direct relationship 

between the age of the mother and the length of 

the interval. For example, the median age of the 

mothers whose previous child had been born 12 

months or less before the sample child was 24.3 

years; when the previous child had been born at 

least 120 months before the sample child, the 

median age of the mothers was 36.6 years. 

It is a common belief that couples prefer to 

have both boys and girls in their families, but 

that there is a preference for boys. If thk is true, 

then for a given number of children, a higher 

proportion of mothers with all children of the 

same sex would expect to have additional 

children than those with children of both sexes, 

and a higher propmtion of mothers with all girls 

than mothers with all boys would expect to have 

additional children. The datid in table 5 show 

fairly strong support for the first statement and 

some, though not significant, support for the 

second. 

The difference in the proportion expecting 

additional children between mothers with children of one sex and those with children of both 

sexes was greatest among mothers of two childreri and decreased as the size of the family 

increased, which is the reverse of the direction 

found when the Growth of American Families 

data were analyzed.A 

Age of Mother, Interval Since First Marriage, 

and Age at First Marriage 

There was, in general, an inverse relationship 

between the mother’s age or the length of time 

she had been married at the time the sample 

child was born and the number of additional 

children she expected to have (tables 6 and 7). 

These two variables me related, of course. The 

median interval since first marriage was 11 

months for those mothers under 20 years, 35 

months for those 20-24, 82 months for those 

25-29, and more than 10 years for those 30 

years or over at the time of the sample child’s 

birth (figure 1). 

One reason older women did not expect to 

have as many additional chilchen as did younger 

women was that their families were nearer to 

I50


140


130


120
 u


w 110
 =


K
E 100E


z


~ 50


2 40
 E


30


20’


10’


L_l_
 Under 20-24 

20 over 

AGE IN YEARS 

Figure 1. Madian length of marriage, in months, for U.S. women 

aged 1544 years. 

completion. Table C shows the average number 

of children women in each class already had as 

well as the average number expected. It also 

shows, however, that even when the number 

expected is standardized to control for the 

differences in the number already living, older 

women still expected to have fewer additional 

children than did younger women. 

An exception to the general observation on 

the relationship between age and duration of 

marriage and the number of additional children 

expected was that mothers of one child who 

were under age 20 when that child was born 

expected to have fewer additional children than 

did those aged 20-24. Data from the NNS 

indicate that a high proportion (42 percent) of 

the mothers of first births who were aged 15-19 

had been married for less than 8 months at the 

time of the child’s birth; over half (56 percent) 

had not finished high school; and many (46 

percent) were classified as having a family 

income of under $3,000. All of these factors 

may make their expectations of limiting their 

families unrealistic, particularly in view of the 

long period of potential childbearing ahead of 

them. 

It is possible that those women who married 

before they were 20 really did not intend to 

7 
Table C. Average number of children now living, expected, in expected completed family, expected when standardized for number now living, by age of mother: United States, 1964-66 National Natality Survey 

Average number of children 

Now 

living Expected completed 

family 

standardized 

for number 

now living 

Alleges . . . . . . . . . . . . . . . . . 2.78 .95 3.73 .95 

Under 20years . . . . . . . . . . . . . . . . 1.35 1.54 2.89 1.01 

20-24 years . . . . . . . . . . . . . . . . . . 2.00 1.25 3.25 1.05 

25-29 years . . . . . . . . . . . . . . . . . . 3.06 .80 3.86 .96 

30-34 years . . . . . . . . . . . . . . . . . . 4.06 .42 4.48 .60 

35years And over . . . . . . . . . . . . . . . 4.97 .22 5.19 .34 

Age of mother In expected Expected when 

have large families. When all of the women in pear, and among those with five children or


the survey were classified according to age at more it no longer existed.


first marriage regardless of age at the time of the Because expectation of additional children


sample child’s birth, those mothers of one child has been shown to be related to the mother’s


who were first married at ages 20-24 expected to age, it is important to know something of the


have more additional children than those first age differences among women in the various


married before age 20 (table 8). Even when the income classes. If the number of children is held


mothers’ expectation of additional children was constant, women in families with low incomes


standardized to control for the number already tended to be younger than women in higher


living, those who first married in the early income families. For example, among mothers


twenties had higher expectations than those whose first birth was the sample child, 62


married before age 20 (table D). The difference percent of those in families with incomes under


in expectation and realization can be estimated $3,000 were under age 20 at the time of the


by comparing the number of children already child’s birth compared to 41 percent in families


born to those women who first married before with incomes of $3,000-$4,999, 26 percent in


age 18 with the number born to those who families with incomes of $5,000-$6,999, 10


married later. percent in families with incomes of


$7,000-$9,999 and 7 percent in families with 

Family Income incomes of $10,000 or more. 

In general, median age at the time of the 

There was no clear indication that in the early sample child’s birth, median age at first marstages of family formation mothers with low riage, and median interval since first marriage 

incomes expected to have larger families than were directly associated with family income 

those with high incomes (table 9). Among (table E). The proportion of mothers under age 

mothers of one or two living children, the 20 at the time of the child’s birth, the proporexpectation of additional children was of ap- tion married less than 1 year, and the proportion 

proximately the same magnitude for the high- married before age 18 were inversely associated 

and the low-income classes. Only among with the family income. Thus the mothers in the 

mothers of three or four children did the lower income classes were younger than those in 

differential of higher expectation of additional the higher income classes and had been married 

children among mothers with low incomes ap- for a shorter period, 

8 
Table D. Average number of children now living, expected, in expected completed family, and expected when standardized for number now living, by mother’s age at first marriage: United States, 1964-66 National Natality Survey 

Average number of children 

Expected when 

Age of mother at first marriage Now 

In expected standardized 

family now living 

Alleges . . . . . . . . . . . . . . . . . 2.78 .95 \ 3.73 I .95 

Under 18years . . . . . . . . . . . . . . . . 3.13 .84 3.97 .90 

18-19 years . . . . . . . . . . . . . . . . . . 2.64 .96 3.60 .94 

20-21 years . . . . . . . . . . . . . . . . . . 2.60 1.05 3.65 1.01 

22-24 years . . . . . . . . . . . . . . . . . . 2.84 1.00 3.85 1.01 

25yearsand over . . . . . . . . . . . . . . . 2.69 .84 3.54 .83 

living Expected completed for number 

Despite the median interval of 34 months 

since first marriage for mothers in families with 

incomes under $3,000 and 83 months for those 

in families with incomes of $10,000 or more, 

mothers in both income classes had an average 

of 2.84 living children. However, the mothers in 

families with incomes tqder $3,000 expected to 

have 1.07 additional children while those in the 

top income class expected to have 0.88 additional children. Therefore the size of the expected completed families of the highest income 

women was smaller than that of the 10west 

income women. The number of living children 

mothers in the middle-income farnili& already 

had was lower than at either of the income 

extremes and their expected completed family 

size was also smaller than that of the women in 

either the highest or lowest income classes. 

When the number of additional children 

expected is standardized for the number already 

living, the number expected is still inverseIy 

proportional to family income although the 

gradient is less. Because the mothers in the lower 

income classes were younger than those in the 

Table E. Average number of childran now living, expacted, in expected completad family, and exp+ctad when standardized for number of children now living; 

median age of mothar at birth of sample child and at first marriage and length of marriage; percentage of mothers under age 20 at birth of sample child, under 

a~ 18 at first marriage, and married lass than 12 months at birth of sample child, by femily income: Unitad States, 1984-86 National Natelity Survay 

Madian age of Average number of children mother (in years) Median Percentage of mothers 

length of Mcrriad 

Now 

living Expected completed 

family 

standardized 

for number 

now living 

of sample 

child 

At first 

marriage 1 

(in months) at birth of 

scmple child 

under 

age 18 

months at 

birth of sample child 

All incomes . . . . 2.78 .95 3.73 .95 25.0 19.8 56.2 13.6 21.8 13.7 

Under $1,000 . 

$1,000-$2,888 . 

. 

. 

. 

. 

. 

. 

. 

. 

. 

. 

2.84 

2.65 

1.10 

1.06 

3.94 

3.81 

1 SXl 

1.02 

22.1 

22.8 I 

18.7 33.9 37.6 

28.3 I 38.9 26.2 

$3,000.$4,888 . . . . . . 2,69 .88 3.65 .95 23.8 19.2 48.2 18.2 30.1 14.5 

S5,0CWW396... . . . 2.75 .82 3.66 .95 24.8 19.7 57.5 8.9 17.1 10.7 

$7,000-$%888 . . . . . . 2.83 .90 3.72 95 27.1 20.7 73.6 3.5 11.7 8.3 

$10,OW and over . . . . . 2.84 .88 3.73 .90 29.2 21.7 82.6 2.1 5.8 6.7 

Family income In expected Expected when At ~nh marriage Under age 20 Married less than 12 

1Married only once. 
higher income ‘classes, this difference could be 

account ed for by age alone; younger women, 

regardless of number of children already living 

or family income, expected to have more children in the future than older women, 

In general, possibly because of the differing 

age distribution among the mothers in the 

several income classes, family income appears to 

be a poor variable to use in predicting differentials in future childbearing, 

Mother’s Employment During Pregnancy 

One of the methods often suggested for 

reducing the birth rate is to give women alternatives to motherhood. The hypothesis is that if 

women had an alternative, such as employment 

outside the home, they would have fewer 

children. If this hypothesis is true and the 

number of chikken the wornan already has is 

held constant, the woman who has been employed outside the home would expect to have 

fewer additional children than the woman who 

has not been ,employed. 

While it is not within the limits of this survey 

to present data on the mother’s employment 

history or her plans for future employment, it is 

possible to examine the differentials in expectation between those mothers who were employed 

during their latest pregnancy and those who 

were not. The data are shown in table 10. 

Except for mothers of one child, the majority 

of the women reported that they had not been 

employed at any time during the pregnancy that 

resulted in the birth of the sample child. Only 

30 percent of all the mothers and 21 percent of 

the mothers of two children or more said that 

they had been employed during pregnancy; 53 

percent of the mothers of one child had been 

employed at some time during pregnancy. Employment during pregnancy is, of course, related 

to other variables presented in this report and 

has been discussed in some detail in an earlier 

report in this series.5 

In general, a smaller proportion of mothers of 

two or three children who were employed 

during pregnancy expected to have additional 

children than did women who were not employed. Mothers who were employed and who 

had two or three children also expected to have 

a lower average number of additional children 

than did those who were not employed. The 

differences are statistically significant for 

mothers of two and of three living children. 

Among mothers of four children or more, there 

were no significant differences in expectation of 

additional children between employed and nonemployed mothers. 

Among mothers of one child, however, a 

higher proportion of those who were employed 

expected to have additional children than did 

those who were not employed. Approximately 

93 percent of those who were employed as 

compared with 90 percent of those who were 

not employed expected to have more children. 

This difference is interesting as mothers who 

were employed during their first pregnancy were 

some what older and better educated than 

mothers who were not employed, 

When the number of children expected was 

standardized for number of living children, 

mothers who were employed expected to have 

0.91 additional children. Mothers who were not 

employed expected to have 0.95 additional 

children. 

Education of Mother and Father 

Only among mothers of one child was there 

any clear relationship between level of education 

and the reported expectation of having more 

children. The proportion expecting to have 

additional children was directly related to both 

parents’ levels of education (tables 11 and 12). 

The average number of additional children expected was not so closely related to level of 

education. The number of additional children 

expected was higher when either parent had 

only an elementary school education than when 

either had attended but not completed high 

school. 

The mothers who had attended but not 

graduated from high school had low expectation 

of additional children regardless of how many 

they already had. They may just be poor 

predictors of their future fertility, They were 

younger on the average than women at the other 

levels of educational attainment; their median 

age was only 23.4 years; and 27 percent of them 

were under 20 at the time of the birth of the 

sample child. A high proportion of them had 

their first child soon after marriage. Among 

10 
those in the survey who had just had their first 

child, 32 percent had been married for less than 

8 months when the child was born as compared 

with approximately 21 percent of those who 

had not gone beyond elementary school, 21 

percent of those who were high school graduates, 18 percent of those who had some college, 

and 8 percent of those who were college 

graduates. Yet they expected to have fewer 

additional children than mothers at any other 

level of educational attainment. 

The number of children in the expected 

completed family was inversely proportional to 

the mother’s level of education (table F). 

Mothers who had not gone beyond elementary 

school expected to complete their families with 

4.81 children while those who had graduated 

from college expected to complete their families 

with 3.40 children. The majority of the children 

in the expected completed family (approximately 83 percent of the children if the mother 

had not gone beyond elementary school, 72 

percent if she had graduated from high school, 

and 65 percent if she had graduated from 

college) were children she already had. Thus the 

number of additional chkh-en expected was 

directly proportional to the mother’s level of 

education. 

When the number of additional children 

expected was standardized for the number already living, mothers who had not gone beyond 

elementary school expected to have the largest 

average number of additional children. Mothers 

who were college graduates expected almost as 

many, and mothers who had ~ttended but not 

graduated from high school expected the fewest. 

The same was not true for the fathers’ level of 

education (table G). Mothers and fathers at the 

two educational extremes were the oldest, and 

those who had completed 1-3 years of high 

school ‘were the youngest (tables F and G). 

Race of Mother 

Among married mothers of one or two 

children, a higher proportion of white mothers 

expected to have additional children than did 

Negro mothers; among mothers with three or 

more children, a higher proportion of Negro 

than of white mothers expected to have additional chikken (figure 2 and table 13). In addition, among mothers with one or two children 

who expected to have more children, a higher 

proportion of white mothers than of Negro 

mothers definitely expected more. 

Overall, white mothers expected to have 0.98 

additional children and Negro mothers expected 

to have 0.73 additional children. White mothers 

had, on the average, 2.66 children living at the 

time of the sample child’s birth. If their expectations were realized, they would complete their 

families with 3.64 children. Because Negro 

mothers already had an average of 3.68 living 

children, the y would complete their families 

with 4.41 children per mother even though their 

expectation of additional children was lower 

Table F. Average number of children now living, expectad, in expected completed family, and expected when standardized for 

number now living; median family income, median age of mother, and median length of marriage, by mother’s level of education: 

United States, 1964-66 National Natality Survey 

Average number of children 

Median Median Median 

Level of 

mother’s education 

Now 

living Expected 

Expected when In expected standardized 

completed for number 

family now living 

family 

income 

age of mother 

(in years) 

length of marriage 

(in months) 

All levels . . . . . . . . 2.78 .95 3.73 .95 $5,610 25.0 56.2 

Elementary school only . . . . 4.00 .81 4.81 1.05 $3,310 27.1 91.6 

High school, I-3 years . . . . . 2.92 .82 3.74 .86 $4s0 23.4 56.8 

4 years ..,... 2.55 1.01 3.55 .95 $6,050 25.9 51.3 

College, 1-3 years . . . . . . . 2.45 1.03 3.47 .96 $7,080 26.0 52.3 

4 years or more . . 2.21 1.19 3.40 1.02 $8,010 28.1 53.6 

11

Table G. Average number of children now living,, expected, in expected completed femily, end expect I when standardized for 

number now Iiving; median fami Iy income and median age of father: United States, 1964-66 Nation Natality Survey 

I Average number of children 

Median Madian 

In expected Expected when family age of 

Lavel of father’s education	 Now standardized income father 

living Expected completed for number (in years) 

All levels . . . . . . . . . . . . . . . . . . 2.78 

Elementary school only . . . . . . . . . . . . . . 3.84


Highschool, l-3years , . . . . . . . . . . . . . . 2.82


4years . . . . . . . . . . . . . . . . 2.52


College,l-3 yea~ . . . . . . . . . . . . . . . . . 2.42


4years ormore . . . . . . . . . . . . . 2.48


Race of mother 

White 

Negro I-1 Iiiiiil

tFour Five 

NUM8ER OF LIVING CHILDREN 

Figure 2. Percentage of mothers who expect to have additional 

childran, according to race of mother and number of living 

children. 

than that of the white mothers (table 13). 

However, even when the average number of 

1.08

family now living 

.95 3.73 .95 $5,610 28.2 

.75 4.59 .94 $3,470 31.5 

.84 3.66 .86 $4,560 27.0 

.99 3.51 .93 $5,820 27.3 

1,13 3.55 1.01 $6,500 27.5 7 3.56 1.04T$8,800 30.3 

additional children expected was standardized 

for the number of children already living, Negro 

mothers still expected to have only 0.84 additional children on the average as compared with 

0.96 expected by the white mothers (table H). 

Although standardization for number of living children or making comparisons between 

mothers with a specific number of children 

controls for the number of children the mother 

already has, it does not control for any of the 

other variables which may have some influence 

on the mother’s expectation of additional children. Data on some of these variables are 

presented in table J. For all mothers having 

births during 1964-66 and for mothers with a 

specified number of children, white mothers 

were older at the time of the birth and at first 

marriage; had been married longer; were mem= 

hers of families with higher incomes; and had 

achieved higher levels of education than had 

Negro mothers. Expectations of additional children were affected by these variables; therefore, 

their possible influence must be taken into 

account when child-specific comparisons are 

made between white and Negro mothers. 

Because there were only 48,000 mothers of 

minority races other then Negro, it is not 

possible to give much detail concerning their 

expectation of additional children. In general, 

however, the data available seem to indicate that 

their expectations of future childbearing were 

lower than those of the white mothers but 

higher than those of the Negro mothers. 

12 
Table H. Average number of children now living, expected, in expeeted completed family, and expected when standardized for number now living, by race of mother: United States, 1964-66 National Natality Survey 

Race 

All 

Average number of children mothers 

Nonliving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.78 

Expected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95 

Inexpeeted completed family . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.73 

Expeeted when standardized for 

number non living . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95 

White Negro 

2.66 3.68 

.98 .73 

3.64 4.41 

.96 .84 

Geographic Region and Metropolitan Status of 

Residence 

Among mothers with one or two living 

children, those who resided in standard metropolitan statistical areas (SMSA’S) expected to 

have more additional children than did those 

who resided outside SMSA’S. Among mothers 

with three living children or more, those who 

resided in metropolitan areas expected to have 

fewer additional children than did those who 

resided outside metropolitan areas (table 14). 

This is not due to the racial composition of the 

population. Among mothers with one, two, or 

three children, the proportion of residents of the 

nonmetropolitan areas who were white was 

higher than the proportion of residents of the 

metropolitan areas, which is the reverse of what 

would be expected were race of the mother the 

determining factor. 

When the mothers are classified by geographic 

region of residence, mothers in the Northeast 

and North Central Regions generally expected to 

have the highest average number of additional 

children, followed by those in the West, with 

mothers in the South expecting the fewest 

additional children. When the number of children expected was standardized for number of 

living children, mothers in the Northeast expected to have 1.02 additional children while 

those in the South expected to have only 0.89 

additional children. 

Because the racial composition of the South is 

different from the rest of the United States 

(approximately 21 percent of the mothers in the 

South were Negro compared with about 10 

T 

percent in each of the other three regions), the 

possibility exists that the lower expectation in 

the South is due to the high proportion of Negro 

mothers. When the expectation of additional 

children is computed separately for white and 

Negro mothers in the South and the results are 

standardized to the number of living children of 

white and Negro mothers in the United States, it 

is seen that at least two factors contribute to the 

lower expectation of additional children in the 

South. One is the high proportion of Negro 

mothers. who, in general, expected to have fewer 

additional children than did white mothers. 

More interestingly, however, Negro mothers in 

the South expected more additional children 

than did Negro mothers in the entire United 

States, but white mothers in the South expected 

fewer additional children than did white 

mothers in the entire United States. Thus the 

regional difference was caused primarily by the 

low expectation of the white mothers rather 

than by the racial distribution since the Negro 

mothers in the South expected to have more 

additional children than did Negro mothers in 

the rest of the country (table K). 

SUMMARY AND CONCLUSIONS 

The married women who had babies in 

1964-66 had, on the average, 2.78 children. 

They expected to have 0.95 additional children 

and thus will complete their families with 3.73 

childen if their expectations are correct. This 

estimate is, as expected, higher than those 

derived from surveys of all married women. All 

of the women in the NNS had demonstrated 

13

Table J. Percent distribution of mothers and median age, age at first marriage, length of marriage, family income, and education, by 

race and number of living children: United States, 1954-56 National Natality Survey 

Number of living children 

Race of mother 

All mothers . . . . . . . . . . . . . . . 

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

Negro . . . . . . . . . . . . . . . . . . . . . 

All other races . . . . . . . . . . . . . . . . . 

Alimothers . . . . . . . . . . . . . . . 

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

Negro . . . . . . . . . . . . . . . . . . . . . 

All mothers . . . . . . . . . . . . . . . 

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

Negro . . . . . . . . . . . . . . . . . . . . . 

All mothers . . . . . . . . . . . . . . . 

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

Negro . . . . . . . . . . . . . . . . . . . . . 

All mothers . . . . . . . . . . . . . . . 

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

Negro . . . . . . . . . . . . . . . . . . . . . 

All mothers . . . . . . . . . . . . . . . 

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

Negro . . . . . . . . . . . . . . . . . . . . . 

Total One Two Three Four Five Six or more 

I 

Percent distribution 

100.0 100.0 100.0 100.0 100.0 100.0 100.0 

86.9 90.6 88.6 88.0 86.6 83.1 70.7 

11.7 8.2 9.4 11.0 12.5 15.2 27.8 

1.4 1.2 2.0 1.0 0.9 1.7 1.4 

Median age (in years) 

25.0 21.8 23.8 26.7 29.0 30.8 33.5 

25.1 21.9 23.9 27.0 29.3 31.3 34.1 

24.8 20.4 22.6 23.9 25.8 28.6 32.1 

Median age at first marriage (in years) 

19.6 19.8 19.7 19.6 19.6 19.6 19.1 

19.7 19.8 19.7 19.5 19.6 19.5 19,4 

19.3 19.4 19.3 19.7 18.9 19.8 18.4 

Median length of time married (in months) 

56.3 14.6 44.9 83.1 105.7 over 120 over 120 

56.4 15.1 45.9 86.9 108.4 over 120 over 120 

56.0 8.9 31.4 47.5 79.3 105.2 over 120 

Median family income (indollars) 

5,610 5,190 5,680 5,880 6,080 5,730 5,200 

5,910 5,350 5,890 6,140 6,470 6,220 6,260 

2$70 3,040 3,180 3,470 2,680 2,750 2,570 

Median education (in years) 

12.3 12.4 12.4 12.3 12.2 11.0 10.8 

12.3 12.5 12.4 12.3 12.3 12.1 11.9 

11.3 12.3 11.8 11.9 11.0 10.5 9.2 

fertiiity by the birth of a child shortly before have. Yet they were, for the most part, young 

they were queried about their expectations of women with many more years of possible 

having additional children. childbearing ahead ofthem. 

Whether this is an accurate prediction of the The number of additional children expected 

number of additional children the women will by the mothers who were under age20 when the 

actually have is problematical. According to sample child was born seemed particularly low 

their stated expectations, they have already had in view of the number of years of possible 

75 percent of the children they ever expectto childbearing they had aheadof them. They had 

14 
Table K. Average number of additional children expected, by 

race of mother andavarage number axpected by region when 

standardized to specified race for number of Iiving children: 

United States, 1964-66 National Natality Suwey 

I Race of mother 

Geographic region 

EFF’=E 

Average 

United States . . .95 .98 .73 .89 

Standardized 

Northaast . . . . . . . . 

NortN Central . . . . . 

South . . . . . . . . . . 

West . . . . . . . . . . 

started childbearing early and the majority had 

relatively low levels of education. Both factors 

have been shown to be associated with high 

Ievles of completed fertility, and low levels of 

education are associated with poor ability to 

predict future fertility. 6~7 

Despite the reservations about the accuracy of 

the estimates of the actual number of children 

these young, recently fertile women will have in 

the future, the data are useful for investigating 

different ials in the women’s perception of their 

future fertility at different stages of family 

formation. Only two of the variables considered 

here–the age of the mother and whether her 

children were of the same or different sexes— 

showed a differential in the same direction for 

each specified number of children. Other variables, such as the interval since the mother’s first 

marriage or preceding child and whether she had 

ever had a child who died in infancy, were 

generally consistent. 

The proportion of mothers who expected to 

have additional children did not seem to be 

influenced by whether the mother reported any 

fetal deaths, except for mothers of one child. It 

is possible that these mothers had been told that 

they had impairments which would make additional children unlikely; over half of those who 

reported that they did not expect to have any 

more children responded “Definitely no.” Nor 

did the mothers’ residence inside or outside a 

metropolitan area seem to have much influence 

on whether she expected to have more children. 

For some of the variables, however, the 

direction of any differential reversed after the 

first one or two children. Mothers of one child 

who were in high family income or education of 

father categories, who were employed during 

pregnancy, who were white, or who lived outside of the South were more likely to expect 

additional children than those who were in low 

family income or education of father categories, 

who were not employed, Negroes, or residents 

of the South. Conversely, mothers of three 

chiIdren who were in low family income or 

education of father categories, who were not 

employed during pregnancy, who were Negro, or 

who lived outside of the West were more likely 

to expect additional children than those in high 

family income or education of father categories, 

who were ‘ employed during pregnancy, who 

were white, or who lived in the West. 

Cohort or age-specific analysis might help 

explain some of the reversal. It seems likely, 

however, that there are real differences between 

the population composed of mothers of one 

child and that composed of the mothers of 

three. These differences probably are the result 

of two selection processes. 

Almost all of the married women in the 

United States want to have at least one child. 

The mothers of one child are thus a sample of all 

the women who are capable of having children. 

However, less than two-thirds of the women in 

the 1960 Growth of American Families Survey 

said that they wanted three or more children. 

The mothers of three children then are those 

women who wanted to have that many and 

those who had them even though they did not 

really want them. The women who wanted only 

one or two children and who successfully 

prevented unwanted pregnancies are no longer in 

the sample. Those who wanted only one or two 

children but who were not successful in preventing unwanted pregnancies are included with 

those who had always intended to have three 

children or more. 

Other data show that couples in the lower 

socioeconomic classes are less likely to use 

contraception than are those in the higher 

classes and are less likely to be successful users 

even if they have tried contmception.3 They 

would thus be more likely than those in the 

upper socioeconomic classes to have three or 

15 
more children even though they had not expected to. With a history of failure to prevent 

pregnancy, mothers of three children would be 

more likely to report that they expected to have 

additional children than they had been as 

mothers of one child who had not yet found 

that they were not successful at preventing 

pregnancy. 

The mother’s level of education warrants 

special consideration. It is one of the most 

common measures used in fertility studies because it is easy and reliable to measure and 

because it has appeared to be a good measure 

with consistent differentials in expected and 

completed fertility. There were no consistent 

differentials in the National Natality Survey 

when the mothers were classified according to 

the number of children they had. When the expected completed size of family was computed, 

there appeared to be an inverse relationship with 

the level of education. Much of the expected 

family, however, is accounted for by the children the mother already had. 

It is possible that the lack of the expected 

differentials among mothers with the specified 

number of children is an artifact due to the 

differing age distributions. It is also possible that 

differences in fertility according to the m@her’s 

level of education are lessening or shifting 

direction. In either case, the lack of the expected differentials shggests a need for further 

investigation, 

REFERENCES


lWhelpton, P. K., Campbell, A. A., and Patterson, J. E.: 

FertiZity and Family Plannzkg in the United States. Princeton, 

New Jersey. Princeton University Press, 1966. 

2U.S. Bureau of the Census: Marriage, fertWty and childspacing, June 1965. Cur-rent Pofndutims Refwts, Series P-20-NG. 

186. Washington. U.S. Government Printing Office, Aug. 1969. 

%1.S. Bureau of the Census: Household and family characteristics, March 1965. Current Population Reports, Series 

P-20-No. 153. Washington. U.S. Government Ptiting Office, 

Aug. 1966. 

4Freedman, D. S., Freedman, R., and Wbelpton, P. K.: Size 

of family and preference for children of each sex. A m. j. SocioL, 

66(2): 141-46, Sept. 1960. 

5Nation~ Centm for Hmlth Statistics: Employment during 

pregnancy, Iegiti-te live births, United States, 1963. Vital and 

Health Statrktics. PHS Pub. No. 1000-Senes 22-No. 7. Pubfic 

Health Service Washington. U.S. Government Printing Office, 

Sept. 1968. 

6Bumpass, L., and Westoff, C, F.: The Predictionof 

com leted fertility. Demography, 6(4), Nov. 1969.-

?Campbell, A. A., Whelpton, P. K., and Tomasson, R. F.: 

The reliability of birth expectation of U.S. wives. Proceed@s of 

the International Population Conference, New York, 1961. 

8National Center for Health Statistics: Vital Statistics of the 

Uns’ted States, Vol. I, 1964, 1965, and 1966. Public Health 

Service. Washington. U.S. Government Printing Office, May 

1969. 

‘National Center for Health Statistics: Replication: an 

approach to the analysis of data from complex surveys. PHS 

Pub. No. 1000-Series 2-No. 14. Public Health Service. Washington. U.S. Government Printing Office, Apr. 1966. 

16 
Table 1. 

2. 

3. 

4. 

5. 

6. 

7. 

8. 

9. 

10. 

LIST OF DETAILED TABLES 

Average annual number of mothers having legitimate births during 1964-66, percent distribution of mothers by 

whethar they expected to have more children, and avarage number of additional children expected by all mothers, 

by mothers expecting additional children, by mothers definitely expecting additional children, and by mothers 

probably expecting additional children, according to number of living children: United States, 1964-66 National 

Natality Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Average annual number of women who had legitimate births during 1964-66, percentage expecting to have 

additional children, and average number of additional children expected by all the mothers and by those expecting 

to have additional children, according to number of living children and number of fetal deaths: United States, 

1964-66National NatalitySurvey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Average annual number of women who had legitimate births during 1964-66, percentage expecting to have 

additional children, and average number of additional children expected by all the mothers and bythosaexpacting 

to have additional children, according to number of living children and number of infant deaths: United States, 

1964-66National NatalitySurvey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Average annual number of women who had legitimate births during 1964-66, percentage expecting to have 

additional ch’ildren, and average number of additional children expected by all the mothers and bythoseexpacting 

to have additional children, according to number of living children and interval since birth of preceding 

child: UnitedStates,1964-66National NatalitySurvey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Average annual number of wornen who had legitimate births during 1964-66, percentage expecting to have 

additional children, and average number of additional children expected by all the mothers and bythoseexpacting 

to have additional children, according to number and sex of living children: United States, 1964-66 National 

NatalitySurvey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Average annual number of women who had legitimate births during 1964-66, parcentaga expecting to have 

additional children, and average number of additional children expected by all the mothers and bythosaexpacting 

to hava additional children, according to number of living children and age of mother at birth of sample 

child: UnitedStates,1964-66National NataiitySurvey . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . 

Average annual number of women who had legitimate births during 1964-66, percentage expecting to have 

additional children, and average number of additional children expected by all the mothers and bythoseexpacting 

to have additional children, according to number of Iiving children and interval since first marriage: Unitad Statas, 

1964-66National NatalitySurvey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Average annual number of women who had legitimate births during 1964-66, percentage expecting to have 

additional children, and average number of additional children expected by all the mothers and bythose expecting 

to have additional children, according to number of living children and age of mother at time of first 

marriaga: United States, 1964 -66 National Natality Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Average annual number of women who had legitimate births during 1964-66, percentage expecting to have 

additional children, and average number of additional children expected by all the mothers and bythoseexpacting 

to have additional children, according to number of living children and family income: United States, 1864-6S 

Na&onal Natality Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Average annual number of women who had legitimate births during 1964-66, percentage expecting to have 

additional children, and average number of additional children expected by all the mothars and bythosaexpacting 

to hava additional children, according to number of living children and mother’s employment status during 

pregnancy: Unitad Statas, 1964-66 National Natality Survay . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Page 

19 

20 

21 

22 

23 

24 

25 

26 

27 

28 

17 
LIST OF DETAILED TABLES–Con, 

Page 

Table 11.	 Average annual number of women who had legitimate births during 1964-66, percentage expecting to have 

additional children, and average number of additional children expected by all the mothers and by those expecting 

to have additional children, according to number of living children and level of mother’s education: United States, 

1964-66 National Natality Survey. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..29 

12.	 Average annual number of women who had legitimate births during 1964-66, percentage expecting to have 

additional children, and average number of additional children expected by a;l the mothers andby those expecting 

to have additional children, according to number of living children and level of father’s education: United States, 

1964-66 National Natality Survey. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..30 

13.	 Average annual number of women who had Iagitimate births during 1964-66, percentage expecting to have 

additional children, and average number of additional children expected by all the motherland by those expecting 

to have additional children, according to number of living children and race of mother: United States, 1964-66 

National NataiitySurvey . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,. . . . . . . 31 

14.	 Average annual number of women who had legitimate births during 1964-66, percentage expecting to have 

additional children, and average number of additional children expected by all the mothers and by those expecting 

to have additional children, according to number of living children, geographic region, and metropolitan status of 

residence: United States, 1964-66 National Natal ity Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 

18

Table 1. Average annual number of mother$ having legitinwte births during 19S4-66, percent distribution ofmothersby whether theyexpected tohavemore children, ati 

averase number of additional children expected by all mothers, by mMhersexpeming adtitionaI children, bymothem definimly expetiingaMtional children, and by 

mothers probably expecting dtitional children, according to numberof Iiving children: United States, 19S4$6National Natality Suwey 

Average number of additional Percent distribution of mothers by response children expected by: Number of 

Number of living children mothers Yes I No Mothers who expect more (in thousands) All — Total mothers Total Definitely Probably Total Definitely kobabi y 

All living children . . . . . . . . 3,430 100.0 54.1 25.5 28.6 17.8 28.2 .95 1.76 2.10 1.45 

. - ==1=-

Onectild. . . . . . . . . . . . . . . . 1,026 100.0 91.6 59.5 32.1 2.9 I 5.5 1.77 1.93 2.19 1.46 

Two children . . . . . . . . . . . . . . 9W 100.0 55.4 18.4 37.0 13.7 30.9 .90 1.62 1.95 1.46 

Three children . . . . . . . . . . . . . 621 100.0 37.9 9.9 279 23.3 36.8 .55 1.44 1.74 1.34 

Fourchildren . . . . . . . . . . . . . . 393 100.0 21.5 5.7 15.8 34.7 43.7 .35 1.61 2.00 1.47 

Fivechildren . . . . . . . . . . . . . . 232 100.0 23.1 6.4 16.7 34.8 42.1 .35 1.51 1.93 1.35 

Sixchildrenormore . . . . . . . . . . 30s 100.0 22.7 4.1 18.6 33.7 43.6 .3S 1.74 2.10 1.66 

— 
Table2. Average annual number of women who hed legitimate births during 1964-66, percentage expecting to have additional 

children, and average number of additional children expected by all themothars and bythosa expecting tohave additional children, 

according to number of Iivingchildren and number of fetal deaths: United States, 1964-66 National Natality Survey 

Number of living children 

and number of fetal deaths 

Onechild, total . . . 

No feteldeaths . . . . . . . 

One fetal death or more . . 

One fetal death . . . . . 

Two fetal deaths or more 

Two children, total . 

No fetal deaths . . . . . . . 

One fetal death dr more . . 

One fetal death . . . . . 

Two fetal deaths or more 

Three children, total 

No fetal deaths . . . . . . . 

One fetal death or more . . 

One fetal death . . . . . 

Two fetal deaths or more 

Four children, total . 

No fetal deaths . . . . . . . 

One fetal death or more . . 

One fetal death . . . . . 

Two fetal deaths or more 

Five children, total . 

No fetal deaths . . . . . . . 

One fetal death or more . . 

One fetal death . . . . . 

Two fetal deaths or more 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

. . . . . . . . . . 

Six children or more, total . . . . . . . 

No fetal deaths . . . . . . . . . . . . . . . . . 

One fetal death or more . . . . . . . . . . . . 

One fetal death . . . . . . . . . . . . . . . 

Two fetal deaths or more . . . . . . . . . . 

Percentage Number of 

expecting mot hers 

additional 

(in thousends) children 

1,026 91.6 

915 92.4 

110 84.7 

87 86.1 

23 79.3 

900 55.4 

720 55.5 

180 55.3 

134 57.2 

45 49.5 

621 37.9 

454 37.9 

166 37.7 

121 38.9 

46 34.6 

393 21.5 

279 21.2 

114 22.4 

73 22.4 

41 22.5 

232 23.1 

147 22.3 

85 24.4 

50 25.5 

35 22.9 

308 22.7 

179 22.8 

128 22.6 

74 23.2 

55 21.8 

Average number of additional 

children expected by: 

All Mothers who 

mothers expect more 

1.77 1.93 

1.79 1.94 

1.59 1.88 

1.62 1.88 

1.47 1.85 

.90 1.62 

.92 1.65 

.83 1.51 

.85 1.49 

.78 1.57 

.55 1.44 

.56 1.47 

.52 1.38 

.55 1.42 

.43 1.25 

.35 1.61 

.33 1.55 

.40 1.77 

.35 1.58 

.47 2.10 

.35 1.51 

.34 1.50 

.37 1.53 

.38 1.51 

.36 1.57 

.39 1.74 

.39 1.69 

.41 1.80 

.40 1.72 

.42 1.91 

20 
Table 3. Average annual number of women who had legitimate births during 1954-66, percentage expecting to have additional 

children, and average number of additional children expected by all the mothers and by those expecting to have additional children, 

according to number of living children and number of infant deathx United States, 1964-66 National Natality Survey 

Average number of additional 

Number of living children 

Number of 

mothers expecting 

children expected by: 

and number of infant deaths (in thousands) 

additional 

children 

==I=%= 

Onechild, total . . . . . . . . . . . . . 1,026 91.6 1.77 I 1.93 

No infant deaths . . . . . . . . . . . . . . . . 1,010 91.7 1.77 1.93 

Oneinfant death or more. . . . . . . . . . . . 16 63.4 1.59 1.91 

Twochildren, total . . . . . . . . . . . 900 55.4 .90 1.62 

No infant deaths . . . . . . . . . . . . . . . . 55.5 .91 1.63 

Onainfant death or more. . . . . . . . . . . . 38 52.6 .76 1.45 

Three children, total . . . . . . . . . . 621 37.9 .55 1.44 

Noinfantdeaths . . . . . . . . . . . . . . . . 582 38.2 .55 1.44 

Oneinfant death or more. . . . . . . . . . . . 38 32.8 .51 1.54 

Four children, total . . . . . . . . . . . 383 21.5 .35 1.61 

No infant deaths . . . . . . . . . . . . . . . . 364 22.1 .36 1.62 

Oneinfantdeath or more. . . . . . . . . . . . 29 14.8 .23 1.54 

Percentage 

Five children, total . . . . . . . . . . . 232 23.1 .35 1.51 

No infant deaths . . . . . . . . . . . . . . . . 307 23.0 .34 1.49 

Oneinfant death or more. . . . . . . . . . . . 25 24.1 .42 1.73 

Six children or mora, total . . . . . . . 308 22.7 .38 1.74 

Noinfantdaaths . . . . . . . . . . . . . . . . 264 22.5 .37 1.65 

Oneinfant death or more..... . . . . . . . 44 23.8 .54 I 2.26 

21 
Table 4. Average annual number of women who had legitimate births during 1964-66, parentage expecting to have additional 

children, and average number of additional children expected by all the mothers and by those expecting to have additional children, 

according to number of living children and interval since birth of preceding child: United States, 1964-66 National Natality Survey 

Average number of additional 

Percentage Number of children expected by: Number of living children and expacting mothers 

interval since birth of preceding child additional 

(in thousands) children All Mothers who 

Onechild, total . . . . . . . . . . . . . 

No preceding child . . . . . . . . . . . . . . . 

All intervals . . . . . . . . . . . . . . . . . . 

Twochildren, all intervals . . . . . . . . 

Under 12 months . . . . . . . . . . . . . . . 

12-23 months . . . . . . . . . . . . . . . . . 

12-17 months . . . . . . . . . . . . . . . . 

18-23 months . . . . . . . . . . . . . . . . 

24-35 months . . . . . . . . . . . . . . . . . 

36-59 months, . . . . . . . . . . . . . . . . 

60-119 months . . . . . . . . . . . . . . . . . 

120 months and over . . . . . . . . . . . . . 

Three children, all intervals . . . . . . . 

Under 12 months . . . . . . . . . . . . . . . 

12-23 months . . . . . . . . . . . . . . . . . 

12-17 months . . . . . . . . . . . . . . . . 

18.23 months . . . . . . . . . . . . . . . . 

24-35 months . . . . . . . . . . . . . . . . . 

36-59 months . . . . . . . . . . . . . . . . . 

60-119 months . . . . . . . . . . . . . . . . . 

120 months and over . . . . . . . . . . . . . 

Four children, all intervals . . . . . . . . 

Undw12 months . . . . . . . . . . . . . . . 

12-23 months . . . . . . . . . . . . . . . . . 

12.17 months . . . . . . . . . . . . . . . . 

18-23 months . . . . . . . . . . . . . . . . 

24-35 months . . . . . . . . . . . . . . . . . 

36-59 months . . . . . . . . . . . . . . . . . 

60-119 months . . . . . . . . . . . . . . . . . 

120monthsand over . . ., . . . . . . . . . 

Five children, all intervals . . . . . . . . 

Under 12 months . . . . . . . . . . . . . . . 

12-23 months . . . . . . . . . . . . . . . . . 

12.17 months . . . . . . . . . . . . . . . . 

18-23 months . . . . . . . . . . . . . . . . 

24-35 months . . . . . . . . . . . . . . . . . 

36-59 months . . .. . . . . . . . . . . . . . . 

60-119 months . . . . . . . . . . . . . . . . . 

120 months and over . . . . . . . . . . . . . 

SiX children or more, ail intervals . . . . 

Under 12 months . . . . . . . . . . . . . . . 

12-23 months . . . . . . . . . . . . . . . . . 

12-17 months . . . . . . . . . . . . . . . . 

18-23 months . . . . . . . . . . . . . . . . 

24-35 months . . . . . . . . . . . . . . . . . 

36-59 months . . . . . . . . . . . . . . . . . 

60119 months . . . . . . . . . . . . . . . . . 

120 months and over . . . . . . . . . . . . . 

mothers expect more 

1,026 91.6 1.77 1.93 

1,010 91.7 1.77 1.93 

16 83.4 1.59 1.91 

900 55.4 .90 1.62 

44 67.5 1.37 2.03 

342 63.0 1.10 1.74 

176 66.8 1.21 1.81 

166 59.0 .98 1.67 

220 56.6 .89 1.57 

192 48.2 .68 1.41 

81 36.8 .49 1.33 

21 32.2 .39 1.20 

621 37.9 .55 1.44 

15 57.9 .96 1.66 

194 48.1 .77 1.60 

111 48.7 .80 1.64 

83 47.3 .73 1.55 

135 43.2 .60 1.39 

142 32.1 .43 1.35 

108 23.8 .27 1.14 

27 12.2 .12 1.00 

393 21.5 .35 1.61 — 

14 22.0 .36 1.65 

125 30.2 .54 1.80 

67 34.6 .57 1.66 

58 25.1 .51 2.02 

77 20.8 .36 1.74 

94 18.1 .24 1.31 

71 12.4 .15 1.24 

12 16.9 .22 * 

232 23.1 .35 1.51 

11 15.6 .22 1.41 

72 30.2 .57 1.88 

40 29.2 .53 1.81 

32 31.6 .62 1.97 

59 25.3 .32 1.25 

51 16.2 .19 1.20 

37 16.5 .23 1.36 

3 * * * 

308 22.7 .39 1.74 

19 25.5 .34 1.33 

114 24.4 .45 1.86 

60 22.3 .37 1.65 

54 26.8 .55 2.06 

77 24.4 .46 1.90 

65 21.0 .33 1.56 

31 15.2 .20 1.29 

2 

22 
Table 5. Average annual number of women who had legitimate births during 1964-66, percentage expecting to have additional 

children, and average numbar of additional children expected by all the mothers and by those expecting to have additional children, 

according to number and sex of living children: United States, 1964-66 National Natelity Survey 

Average number of additional 

Percentage Numberof children expected by: Number and sex of expecting mothers 

living children, additional 

(in thousands) All Mothers who 

children 

Onechild, total . . . . . . . . . . . . . 

Male . . . . . . . . . . . . . . . . . . . . . . 

Female . . . . . . . . . . . . . . . . . . . . . 

Twochildren, total . . . . . . . . . . . 

Both onesex . . . . . . . . . . . . . . . . . . 

Male . . . . . . . . . . . . . . . . . . . . 

Female . . . . . . . . . . . . . . . . . . . 

Bothsexes . . . . . . . . . . . . . . . . . . . 

Three children, total . . . . . . . . . . 

All onesex . . . . . . . . . . . . . . . . . . . 

Male . . . . . . . . . . . . . . . . . . . . 

Female . . . . . . . . . . . . . . . . . . . 

Bothsexes . . . . . . . . . . . . . . . . . . . 

Fourchildren,total . . . . . . . . . . . 

Allonesex . . . . . . . . . . . . . . . . . . . 

Male . . . . . . . . . . . . . . . . . . . . 

Female . . . . . . . . . . . . . . . . . . . 

Bothsexes . . . . . . . . . . . . . . . . . . . 

Fivechildren, total . . . . . . . . . . . 

Allonesex . . . . . . . . . . . . . . . . . . . 

Male . . . . . . . . . . . . . . . . . . . . 

Female . . . . . . . . . . . . . . . . . . . 

Bothsexes . . . . . . . . . . . . . . . . . . . 

Sixchildren ormore, total . . . . . . . 

All onesex . . . . . . . . . . . . . . . . . . . 

Bothsexes . . . . . . . . . . . . . . . . . . . 

mothers expect more 

1,026 91.6 1.77 1.93 

535 91.9 1.79 1.95 

490 91.2 1.75 1.92 

900 55.4 .90 1.62 

446 60.9 .96 1.5B 

235 60.2 .96 1.59 

212 61.7 .97 1.57 

454 50.1 .& 1.67 

621 37.9 .55 1.44 

166 40.8 .62 1.51 

88 40.3 .59 1.46 

78 41.4 .65 1.57 

455 36.8 .52 1.42 

383 21.5 .35 1.61 

60 25.1 .36 1.42 

28 24.8 .36 1.45 

30 25.5 .35 1.38 

333 20.9 .35 1.65 

232 23.1 .35 1.51 

19 24.9 .30 1.22 

11 25.5 .35 1.39 

8 24.0 .24 1.00 

213 22.9 .35 1.54 

308 22.7 .38 1.74 

6 11.B .12 1.00 

302 22.9 .40 1.74 

23 
� � � 

� 

Table6. Average annual number of women who had legitimate births during 1964-66, percentage expecting to have additional 

children, andaverage number of additional children expected by all themothew and bythose expecting tohaw additional children, 

according to number of Iivingchildran and age of mother at birth ofaemple child: United States, 1964-66 National Netality Survey 

Percentage Average number of additional 

and ege of mother at 

birth of sample child 

mothars 

(in thousands) additional 

children All 

mothers 

Mothers who 

expect more 

Onechild, allages . . . . . . . . . . . . 1,026 91.6 1.77 1.93 

Under 20years . . . . . . . . . . . . . . . . . 339 90.7 1.74 1.91 

20-24 years . . . . . . . . . . . . . . . . . . 487 95.0 1.91 2.01 

25-29 years . . . . . . . . . . . . . . . . . . 140 91.6 1,73 1.89 

30-34 years . . . . . . . . . . . . . . . . . . 41 78.1 1.08 1.38 

35yaarsand over . . . . . . . . . . . . . . . 19 47.0 .61 1.30 

Two children, all eges . . . . . . . . . . 900 55.4 .90 1.62 

Under 20yaers . . . . . . . . . . . . . . . . . 110 61.5 1.08 1.77 

20-24 years . . . . . . . . . . . . . . . . . . 444 60.3 1.01 1.68 

25-29 years . . . . . . . . . . . . . . . . . . 234 52.3 .79 1.52 

WX34years . . . . . . . . . . . . . . . . . . 76 41.2 .56 1.35 

%“yeariand over . . . . . . . . . . . . . . . 37 26.0 ,38 1.35 

Three childrenr all ages . . . . . . . . . 621 37.9 .55 1.44 

Under 20years . . . . . . . . . . . . . . . . . 22 63.7 1.00 1.56 

20-24 years . . . . . . . . . . . . . . . . . . 214 44.5 .70 1.50 

25-29 years . . . . . . . . . . . . . . . . . . 224 41.6 .61 1.46 

30-34years . . . . . . . . . . . . . . . . . . 108 23.6 .28 1.20 

35yearsandover . . . . . . . . . . . . . . . 53 13.6 .14 1,00 

Fourchildren, allagas . . . . . . . . . . 393 21.5 .35 1.61 

Under 20years . . . . . . . . . . . . . . . . . 4 

20-24years . . . . . . . . . . . . . . . . . . 78 29.7 .49 1.66 

25-29years . . . . . . . . . . . . . . . . . . 146 27.8 .47 1.67 

30-34years . . . . . . . . . . . . . . . . . . 101 15.5 .22 1.45 

Number of living children Number of expecting children expected by: 

* 35yearsandover . . . . . . . . . . . . . . . 65 7.1 .10 

Fivechiidren, all ages . . . . . . . . . . 232 23.1 .35 1.51 

Under20years . . . . . . . . . . . . . . . . . 

20-24yeara . . . . . . . . . . . . . . . . . . 26 32.6 .51 1.56 

25-29years . . . . . . . . . . . . . . . . . . . 78 30.1 .52 1.56 

30-34years . . . . . . . . . . . . . . . . . . 74 22.6 .30 1.34 

35yearsandover . . . . . . . . . . . . . . . 54 9.2 .10 

Sixchildren ormore, all ages . . . , . . 308 22.7 .38 1.74 

Under20years . . . . . . . . . . . . . . . . . * 20-24years . . . . . . . . . . . . . . . . . . 9 11.6 .16


25-29years . . . . . . . . . . . . . . . . . . 71 28.9 .55 1.90


30-34years . . . . . . . . . . . . . . . . . . 105 24.6 .48 1.87


35yearsandover . . . . . . . . . . . . . . . 123 18.2 .26 1,45


24 
� � � 

� � � 

Table7. Average annual number of women who had legitimate births during 1964-66, percentage expecting to have additional 

children, andaverage number of additional children expected by all themothars and bythose expacting to have additional children, 

according to number of Iivingchildren andinterval since first marriage: United States, 1964-66 National Natality Survey 

Average number of additional 

Number of living Number of	 Percentage children expected by: expecting children and interval mothers 

since first marriage (in thousands) children 

All 

mothers 

Mothers who 

expect more 

One child, all intervals . . . . . . . . . . 1.026 91.6 1.77 1.93 

Under 12months . . . . . . . . . . . . . . . 437 92.1 1.88 2.05 

Under 8months . . . . . . . . . . . . . . 219 91.4 1.82 1.99 

8-n months . . . . . . . . . . . . . . . . 218 92.9 1.96 2.11 

12-23 months . . . . . . . . . . . . . . . . . 292 93.2 1.88 2.02 

12-17 months . . . . . . . . . . . . . . . . 178 93.8 1.91 2.04 

18-23 months . . . . . . . . . . . . . . . . 114 92.4 1.83 1.99 

24-35 months . . . . . . . . . . . . . . . . . 120 95.5 1.76 1.84 

3647 months . . . . . . . . . . . . . . . . . 60 94.4 1.60 1.69 

46-59 months . . . . . . . . . . . . . . . . . 31 69.1 1.41 1.58 

60-119 months . . . . . . . . . . . . . . . . . 60 84.8 1.20 1.41 

120 months and over . . . . . . . . . . . . . 25 56.9 .73 1.28 

Two children, all intervals . . . . . . . . 900 55.4 .90 1.62 

Under 12months . . . . . . . . . . . . . . . 32 64.8 1.02 1.58 

Under 8 months . . . . . . . . . . . . . . 16 62.6 .97 1.55 

8-n months . . . . . . . . . . . . . . . . 15 67.1 1.08 1.61 

12-23 months . . . . . . . . . . . . . . . . . 105 64.1 1.21 1.89 

12-17 months . . . . . . . . . . . . . . . . 32 63.9 1.11 1.73 

15-23 months . . . . . . . . . . . . . . . . 73 64.2 1.25 1.95 

24-35 months . . . . . . . . . . ...” . . . . 188 66.5 1.20 1.80 

3647months . . . . . . . . . . . . . . . . . 167 57.1 .95 1.66 

46-59 months . . . . . . . . . . . . . . . . . 126 56.1 .78 1.40 

60-119 months . . . . . ...’... . . . . . . 230 45.6 .63 1.39 

120monthsandovar . . . . . . . . . . . . . 51 27.8 .40 1.45 

Three children, all intarvals . . . . . . . 621 37.9 .55 1.44 

* * Undar12 months . . . . . . . . . . . . . . . 4 � 

12-23 months . . . . . . . . . . . . . . . . . 12 46.2 .60 1.29 

24-35 months . . . . . . . . . . . . . . . . . 26 60.1 1.06 1.77 

3647months . . . . . . . . . . . . . . . . . 71 57.2 .93 1.63 

48-59 months . . . . . . . . . . . . . . . . . 87 48.2 .77 1.59 

60-119 months . . . . . . . . . . . . . . . . . 285 37.0 .49 1.33 

120monthsand over . . . . . . . . . . . . . 135 16.7 .19 1.15 

Four children, all intervals . . . . . . . . 393 21.5 .35 1.61 

Under 36months . . . . . . . . . . . . . . . 8 

3647months . . . . . . . . . . . . . . . . . 10 33.3 .50 1.49 

46-59 months . . . . . . . . . . . . . . . . . 33 33.0 .61 1,86 

60-119 months . . . . . . . . . . . . . . . . . 190 26.3 .44 1,66 

120monthsand over . . . . . . . . . . . . . 151 10.5 .13 1.24 

Five children, all intarvak . . . . . . . . 232 23.1 .35 1.51 

* Under 60months . . . . . . . . . . . . . . . 9 � � 

60-119months . . . . . . . . . . . . . . . . . 92 28.3 .49 1.74 

120rnonthsandover . . . . . . . . . . . . . 131 18.8 .24 1.28 

Six children or more, all intervals . . . . 306 22.7 .39 1.74 

Under 60months . . . . . . . . . . . . . . . 6 

60-119 months . . . . . . . . . . . . . . . . . 54 22.8 .50 2.22 

120monthsandover . . . . . . . . . . . . . 246 22.3 .36 1.61 

additional 

25 
� 

� 

Table 8. Average annual number of women who had legitimate births during 1964-66, percentage expecting to have additional 

children, and average number of additional children expected by all the mothers and by those expecting to have additional children, 

according to number of Iiving children and age of mother at time of first marriage: United States, 1964-66National Natality Survey 

Percentage Average number of additional 

Number of living Number of expecting children expected by: 

children and age of mother mothers additional 

mothers expect more 

Onechild, all ages . . . . . . . . . . . . 1,206 91.6 1.77 1.93 

Under 18 years . . . . . . . . . . . . . . . . . 206 68.4 1.62 1.83 

18-19 years . . . . . . . . . . . . . . . . . . 343 91.6 1.76 1.92 

20-21 years . . . . . . . . . . . . . . . . . . 254 94.9 1.90 2.01 

22-24 years . . . . . . . . . . . . . . . . . . 147 93.1 1.91 2.05 

25yearsandover . . . . . . . . . . . . . . . 75 85.8 1.55 1.81 

Two children, all ages . . . . . . . . . . 900 55.4 .90 1.62 

Under 18years . . . . . . . . . . . . . . . . . 203 55.2 .91 1.65 

18-19 years . . . . . . . . . . . . . . . . . . 297 54.3 .87 1.60 

20-21 years . . . . . . . . . . . . . . . . . . 206 58.5 1.00 1.70 

22-24 years . . . . . . . . . . . . . . . . . . 121 56.0 .86 1.54 

25yearsandover . . . . . . . . . . . . . . . 74 51.1 .77 1.51 

Three children, all ages. . . . . . , . . . 621 37.9 .55 1.44 

Under 18 years . . . . . . . . . . . . . . . . . 150 38.4 .53 1.37 

18-19 years . . . . . . . . . . . . . . . . . . 205 37.9 .55 1.45 

20-21 years . . . . . . . . . . . . . .. . . . . 142 37.5 .58 1.54 

22-24 years . . . . . . . . . . . . . . . . . . 83 36.7 .55 1.50 

25yearsand over . . . . . . . . . . . . . . . 41 39.3 .50 1.27 

Four children, all ages . . . . . . . . . . 393 21.5 .35 1.61 

Under 18years . . . . . . . . . . . . . . . . . 104 18.5 .26 1.43 

18-19 years . . . . . . . . . . . . . . . . . . 117 22.1 .36 1.70 

20-21 years . . . . . . . . . . . . . . . . . . 87 21.7 .34 1.58 

22-24 years . . . . . . . . . . . . . . . . . . 59 26.2 .46 1.74 

25yearsandover . . . . . . . . . . . . . . . 27 20.5 .32 � 

Fivechildren, all ages . , . . . . . . . . 232 23.1 .35 1.51 

Under 18years . . . . . . . . . . . . . . . . . 64 27.1 .43 1.58 

18-19 years . . . . . . . . . . . . . . . . . . 67 20.5 .35 1.70 

20-21 years . . . . . . . . . . . . . . . . . . 47 23.0 .30 1.28 

22-24 yaars . . . . . . . . . . . . . . . . . . 37 26.7 .39 1.47 

25yearsandover . . . . . . . . . . . . . . . 16 10.0 .10 

sixchildren ormore, all ages . . . . . . 306 22.7 .39 1.74 

Under 18years . . . . . . . . . . . . . . . . . 106 23.7 .43 1.81 

18-19 years . . . . . . . . . . . . . . . . . . 80 17.0 .32 1.90 

20-21 years . . . . . . . . . . . . . . . . . . 53 20.4 .31 1.50 

22-24 years . . . . . . . . . . . . . . . . . . 47 31.2 .52 1.66 

25yearsand over . . . . . . . . . . . . . . . 20 26.5 .44 

at time of first marriage (in thousands) children All Mothers who 

26 
Table9. Average annual number of women who had legitimate births during 1964-66, percentage expecting to have additional 

children, and average number of additional children expected by ail the mothers end by those expacting to have additional children, 

according to number of Iivingchildren and family income: United States, 1964%6 National Natality Survey 

Percentage Average number of additional 

Number of children expectedly: Number of living children mothers expecting 

and fami Iy income additional

(in thousands) children 

All Mothers who 

mothers expact more 

One child, all incomes . . . . . . . . . . 1,026 91.6 1.77 1.93 

Under $1,000 . . . . . . . . . . . . . . . . . 

$l,0W-$2~9 . . . . . . . . . . . . . . . . . 

$3.000-$4,999 . . . . . . . . . . . . . . . . . 

$5,000-.$6j899 . . . . . . . . . . . . . . . . . 

$7,000-$9 /899 . . . . . . . . . . . . . . . . . 

$lO,OOOand over . . . . . . . . . . . . . . . 

Two children, all incomes . . . . . . . . 

Under $1,000 . . . . . . . . . . . . . . . . . 

$1,00062,999 . . . . . . . . . . . . . . . . . 

$3,0004$4,999 . . . . . . . . . . . . . . . . . 

$5,000~6999 . . . . . . . . . . . . . . . . . 

$7,000-$8,999 . . . . . . . . . . . . . . . . . 

$lO,OOOand over . . . . . . . . . . . . . . . 

Three childran, all incomes . . . . . . . 

Under $1,000 . . . . . . . . . . . . . . . . . 

$I,0W-$299 . . . . . . . . . . . . . . . . . 

$3,000-$4$399 . . . . . . . . . . . . . . . . . 

$5,W-$6$99 . . . . . . . . . . . . . . . . . 

$7,000-$8999 . . . . . . . . . . . . . . . . . 

$lO,OOOandover . . . . . . . . . . . ...”. 

Four children, all incomes . . . . . . . . 

Under $1,000 . . . . . . . . . . . . . . . . . 

$1,000-$2,999 . . . . . . . . . . . . . . . . . 

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

$5,000-$6,999 . . . . . . . . . . . . . . . . . 

$7,000-$9,999 . . . . . . . . . . . . . . . . . 

$l0,000andovar . . . . . . . . . . . . . . . 

Fivechildren, all incomes . . . . . . . . 

Under $1,000 . . . . . . . . . . . . . . . . . 

$1,000-$2999 . . . . . . . . . . . . . . . . . 

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

$5,000-$6,999 . . . . . . . . . . . . . . . . . 

$7,000-$9999 . . . . . . . . . . . . . . . . . 

$lO,OOOand over . . . . . . . . . . . . . . . 

Sixchildren ormore, ali incomes . . . . 

Under $1,000 . . . . . . . . . . . . . . . . . 

$1,00042,999 . . . . . . . . . . . . . . . . . 

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

$5,000-$6,999 . . . . . . . . . . . . . . . . . 

$7,000-$9,999 . . . . . . . . . . . . . . . . . 

$l0,000andover . . . . . . . . . . . . . . . 

113 87.9 1.76 2.C3 

141 90.7 1.74 1.92 

236 90.1 1.69 1.87 

231 93.8 1.86 1.99 

185 91.8 1.79 1.96 

119 84.7 1.78 1.88 

900 55.4 .90 1.62 

45 56.1 .88 1.57 

108 56.0 1.01 1.80 

208 58.4 .97 1.66 

263 54.9 .88 1.60 

185 53.2 .& 1.57 

92 53.7 .81 1.50 . 

621 37.9 .55 1.44 

29 47.3 .76 1.61 

63 44.5 .68 1.52 

144 37.1 .54 1.46 

170 37.2 .51 1.36 

142 38.1 .53 1.39 

73 30.7 .48 1.56 

21.5 .35 1.61 

23 33.8 .59 1.75 

35 23.2 .42 1.82 

82 24.4 .33 1.37 

104 20.7 .28 1.34 

96 20.0 .38 1.95 

53 15.3 .28 1.81 

232 23.1 .35 1.51 

18 22.7 .26 1.16 

28 33.0 .51 1.55 

49 24.9 .45 1.82 

56 19.6 .30 1.52 

52 21.3 .32 1.4s 

29 20.7 .23 1.12 

22.7 .39 1.74 

37 19.6 .34 1.75 

51 25.0 .45 1.82 

60 17.4 .38 2.18 

64 24.1 .32 1.32 

57 22.6 .48 2.14 

38 28.7 .38 1.34 

27 
Table IO. Average annual number of women who had legitimate births during 1964-66, percentage expecting to have additional 

children, and average number of additional children expected by all the mothers and by those expecting to have additional children, 

according to number of living children and mother’s employment status during pregnancy: United States, 1964-86 National 

Natality Survay 

Average number of additional 

Percentage Number of living children Number of children expected by: expecting and mother’s employment mothers 

additional status during pregnancy (in thousends) All Mothers who 

children 

mothers expect more 

One child, all statuses . . . . . . . . . . 1,026 91.6 1.77 1.93 

Employed . . . . . . . . . . . . . . . . . . . 540 93.1 1.83 1.97 

Notemployed . . . . . . . . . . . . . . . . . 485 89.9 1.71 1.90 

Two children, all statusas . . . . . . . . 900 55.4 .90 1.62 

Employed . . . . . . . . . . . . . . . . . . . 224 49.9 .75 1.50 

Notemployed . . . . . . . . . . . . . . . . . 677 .57.2 .95 1.66 

Three children, all statusas . . . . . . . . 621 37.9 .55 1.44 

Employ Ed . . . . . . . . . . . . . . . . . . . 115 31.5 .43 1.35 

Notempioyed . . . . . . . . . . . . . . . . . 506 39.3 .57 1.46 

Four children, all statuses . . . . . . . . 393 21.5 .35 1.61 

Employed . . . . . . . . . . . . . . . . . . . 68 19.7 .38 1.84 

Notemployed . . . . . . . . . . . . . . . . . 325 21.9 .34 1.55 

Five children, all statuses . . . . . . . . 232 23.1 .35 1.51 

Employed . . . . . . . . . . . . . . . . . . . 47 23.7 ,32 1.36 

Notemployed . . . . . . . . . . . . . . . . . 185 22.9 .36 1.55 

sixchildren ormora, all statuses . . . . 308 22.7 .39 1.74 

Employed . . . . . . . . . . . . . . . . . . . 51 22.7 .41 1.79 

Notemployed . . . . . . . . . . . . . . . . . 257 22.7 .39 1.73 
� 

� 

Table Il. Average annual number of women who had legitimate births during 1864-66, percentage expecting to have additional 

children, and average number of additional children expected by all the mothers and by those expecting to have additional children, 

according to number of Iivingchildren and level of mother’saducation: United States, 1964%6 National Natality Survey 

Percentage Average number of additional 

Number of children expected by: Number of living children mothers expecting 

and level of mother’saducation (in thousands) 

additional All Mothers who 

children 

One child, all levels . . . . . . . . . . . 

Elementary school only . . . . . . . . . . . .


Highschool, l-3years . . . . . . . . . . . . .


4years . . . . . . . . . . . . . .


Collage, total . . . . . . . . . . . . . . . . . .


l-3yaars . . . . . . . . . . . . .


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


Two children, all levels . . . . . . . . . 

Elementary school only . . . . . . . . . . . .


Highschool, l-3yaars . . . . . . . . . . . . .


4years . . . . . . . . . . . . . .


College, total . . . . . . . . . . . . . . . . .


l-3years . . . . . . . . . . . . .


4yearsor more . . . . . . . . . .


Three children, all levels . . . . . . . . . 

Elementary school only . . . . . . . . . . . .


HighschooI, l-3years . . . . . . . . . . . . .


4 years . . . . . . . . . . . . . .


Collage, total . . . . . . . . . . . . . . . . . .


l-3years . . . . . . . . . . . . .


4yearsormore. . . . . . . . . .


Four children, all levels . . . . . . . . . 

Elementary school only . . . . . . . . . . . .


Highschool, l-3years . . . . . . . . . . . . .


4years . . . . . . . . . . . . . .


College, total . . . . . . . . . . . . . . . . . .


l-3years . . . . . . . . . . . . .


4yearsor more . . . . . . . . . .


Fiva children, all Iavals . . . . . . . . . 

Elementary school only . . . . . . . . . . . .


Highschool,l-3 years . . . . . . . . . . . . .


4years . . . . . . . . . . . . . . .


College, total . . . . . . . . . . . . .. . . . . .


l-3years . . . . . . . . . . . . .


4yearsormore . . . . . . . . . .


Six children or more, all levels . . . . . 

Elementary school only . . . . . . . . . . . . 

Highschool,	 l-3 years . . . . . . . . . . . . . 

4years . . . . . . . . . . . . . . 

Collage, total . . . . . . . . . . . . . . . . . . 

l-3years . . . . . . . . . . . . . 

4yearsormore . . . . . . . . . . 

mothers expect more 

1,026 91.6 1.77 1.83 

65 84.2 1.78 2.11 

228 88.2 1.55 1.80 

498 93.5 1.83 1.96 

233 94.8 1.86 1.97 

140 93.1 1.82 1.95 

94 97.5 1.93 1.98 

900 !55.4 .90 1.62 

79 57.5 1.07 1.87 

210 54.4 .69 1.64 

413 54.3 .87 1.59 

198 58.1 .86 1.56 

126 58.0 .93 1.60 

72 58.2 .87 1.50 

621 37.9 .55 1.44 

56 45.6 .73 1.60 

174 38.1 .49 1.35 

269 36.6 .51 1.39 

110 38.9 .62 1.59 

68 34.2 .53 1.56 

43 46.4 .75 1.62 

383 21.5 .35 1.61 

59 27.6 .44 1.58 

105 19.3 .30 1.54 

164 23.1 .38 1.67 

65 15.7 .25 1.58 

46 16.9 .26 1.54 

18 12.6 � � 

232 23.1 .35 1.51 

48 31.5 .49 1.56 

68 18.7 .27 1.45 

86 22.6 .34 1.51 

30 21.0 .33 1.56 

23 18.7 .32 1.74 

7 28.2 � 

308 22.7 .38 1.74 

105 23.8 .41 1.73 

81 18.0 .39 2.17 

93 22.7 .36 1.58 

30 31.5 .46 1.45 

22 27.7 .42 1.53 

8 42.3 � 

29 
Table 12. Average annual number of women who had legitimate births during 1984-66, percentage expecting to have additional 

children, and average number of additional children expected by all the mothers and by those expecting to have additional children, 

according to number of living children and level of father’s education: United States, 1964-66 National Natality Survey 

Percentage Average number of additional 

Number of living Number of 

expecting ch iIdren expected by: 

children and level mothers 

additional of father’s education (in thousands) All Mothers who 

children 

One child, all levels . . , . . . . . . . . 

Elementary school only . . . . . . . . . . . .


Highschool, l-3 years . . . . . . . . . . . . .


4 years . . . . . . . . . . . . . .


College, total . . . . . . . . . . . . . . . . . .


l-3 years . . . . . . . . . . . . .


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


Two children, all levels . . . . . . . . . 

Elementary school only . . . . . . . . . . , .


Highschool, l-3years . . . . . . . . . . . . .


4 years . . . . . . . . . . . . . .


College, total . . . . . . . . . . . . . . . . . .


l-3 years . . . . . . . . . . . . .


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


Three children, all levels . . . . . . . . . 

Elementary school only . . . . . . . . . . . .


Highschool, l-3 years . . . . , . . . . . . . .


4 years . . . . . . . . . . . . . .


College, total . . . . . . . . . . . . . . . . . .


l-3 years . . . . . . . . . . . . .


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


Four children, all levels . . . . . . . . . 

Elementary school only . . . . . . . . . . . .


Highschool, l-3years . . .. . . . . . . . . . .


4 years . . . . . . . . . . . . . .


College, total . . . . . . . . . . . . . . . . . .


l-3 years . . . . . . . . . . . . .


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


Five children, all levels . . . . . . . . . 

Elementary school only . . . . . . . . . . . .


Highschool, l-3 years . . . . . . . . . . . . .


4 years . . . . . . . . . . . . . .


College, total . . . . . . . . . . . . . . . . . .


l-3 years . . . . . . . . . . . . .


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


Six children or more, all levels . . . . . 

Elementary school only . . . . . . . . . . . .


Highschool, l-3 years . . . . . . . . . . . . .


4 years . . . . . . . . . . . . . .


College, total . . . . . . . . . . . . . . . . . .


l-3 years . . . . . . . . . . . . .


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


mothers expect more 

1,026 91.6 1.77 1.93 

94 84.7 1.62 1.91 

204 88.6 1.58 1.78 

418 91.8 1.78 1.93 

306 95.3 1.94 2.03 

155 95.0 1.90 2.00 

155 95.7 1.97 2.06 

900 55.4 .90 1.62 

111 52.8 .90 1.71 

189 52.1 .83 1,60 

343 55.2 .89 1.60 

257 59.3 .96 1.63 

115 57.0 1.00 1.75 

143 61.1 .94 1.53 

621 37.9 .55 1.44 

98 42.6 .66 1,54 

138 41.0 .56 1.37 

221 34.6 .48 1.38 

164 36.8 .56 1.52 

70 37.1 .54 1.46 

94 36.5 .57 1.56 

393 21.5 .35 1.61 

80 25.9 .39 1.50 

84 19.4 .29 1.47 

141 21.5 .36 1.67 

88 19.6 .35 1.78 

38 19.2 .32 1.68 

51 20.0 .37 1.85 

232 23.1 .35 1.51 

64 30.7 .48 1.56 

56 17.2 .24 1.42 

64 22.6 .36 1.58 

48 20.7 .29 1.41 

22 23.1 .31 1.34 

27 18.8 .28 1.47 

308 22.7 .39 1.74 

122 21.7 .41 1.88 

64 18.2 .33 1.79 

75 19.3 .33 1.69 

47 36.9 .56 1.52 

23 34.8 .46 1.33 

24 38.9 .65 1.68 

30 
Table 13. Average annual number of women who had legitimate births during 1964-66, percentage expecting to have additional 

children, and avera~ number of additional children expected by all the mothers and by those expecting to have additional children, 

according to number of living children and race of mother for the United States and South: Unitad States, 1964-66 National 

Natality Survey 

Percentage Average number of additional 

Number of living children Number of 

expecting children expected by: 

mothers and race of mother additional (in thousands) All Mothers who children 

White, total . . . . . . . . . . . . . . . 

Onechild . . . . . . . . . . . . . . . . . . . 

Two children . . . . . . . . . . . . . . . . . . 

l%reechildren . . . . . . . . . . . . . . . . . 

Fourchildren . . . . . . . . . . . . . . . . . 

Five children . . . . . . . . . . . . . . . . . . 

Sixchildren or more . . . . . . . . . . . . . . 

Negro, total . . . . . . . . . . . . . . . 

Onechild . . . . . . . . . . . . . . . . . . . 

Twochiidren . . . . . . . . . . . . . . . . . . 

Three children . . . . . . . . . . . . . . . . . 

Fourchildren . . . . . . . . . . . . . . . . . 

Five children . . . . . . . . . . . . . . . . . . 

Sixchildren or more . . . . . . . . . . . . . . 

Another races, totel . . . . . . . . . . 

Onechild . . . . . . . . . . . . . . . . . . . 

Twochildren . . . . . . . . . . . . .. . . . . . 

Three children or more . . . . . . . . . . . . 

South 

White, total . . . . . . . . . . . . . . . 

Onechild . . . . . . . . . . . . . . . . . . . 

Twochildren . . . . . . . . . . . . . . . . . . 

Three children . . . . . . . . . . . . . . . . . 

Fourchildren . . . . . . . . . . . . . . . . . 

Fivechildren . . . . . . . . . . . . . . . . . . 

Sixchildren or more . . . . . . . . . . . . . . 

Negro, total . . . . . . . . . . . . . . . 

Onechild . . . . . . . . . . . . . . . . . . . 

Twochildren . . . . . . . . . . . . . . . . . . 

Three children . . . . . . . . . . . . . . . . . 

Fourchildren . . . . . . . . . . . . . . . . . 

Fivechildren . . . . . . . . . . . . . . . . . . 

Sixchiidren or more . . . . . . . . . . . . . . 

mothers expect more 

3,025 55.3 .98 1.77 

930 92.2 1.80 1.95 

798 55.9 .91 1.63 

546 37.9 .55 1.45 

340 20.5 .33 1.64 

193 22.8 .34 1.51 

218 23.3 .38 1.64 

407 44.7 .73 1.63 

84 85.7 1.45 1.69 

85 49.8 .77 1.56 

68 40.3 .56 1.39 

49 27.5 .41 1.51 

35 23.4 .37 1.57 

86 21.6 .43 1.99 

48 54.5 .89 1.64 

12 87.7 1.66 1.89 

18 62.7 .94 1.49 

18 24.1 .34 1.40 

856 54.3 .91 1.68 

277 90.1 1.65 1.84 

236 52.3 .83 1.59 

156 32.3 .45 1.39 

80 17.8 .23 1.30 

51 26.7 .37 1.38 

55 24.7 .38 1.53 

231 45.8 .78 1.69 

41 83.9 1.46 1.74 

47 56.2 .84 1.50 

36 45.7 .67 1.47 

29 32.0 .54 T.69 

22 26.5 .45 1.69 

56 24.2 .53 2.20 

31 
Table 14. Average annual number of women who had legitimate births’ during 1964-66, percentage expecting to have additional 

children, and average number of additional children expected by all the mothers and by those expecting to have additional children, 

according to number of living children, geographic region, and metropolitan status of residence: United States, 1964-66 National 

Natal ity Su rvey 

Percentage Number of living children, Numberof 

expecting geographic region, mothers 

additional 

and metropolitan status (in thousands) children 

= 

One child 

United States . . . . . . . . . . . . . . 1,026 91.6 I 1.77 I 1.93 

inside SMSA . . . . . . . . . . . . . . . . . . 669 91.7 1.80 1.96 

Outside SMSA . . . . . . . . . . . . . . . . . 357 91.3 1.72 1.89 

Northeast . . . . . . . . . . . . . . . . 241 92.5 1.92 2,08 

lnsideSMSA . . . . . . . . . . . . . . . . . . 191 92.3 1.89 2.05 

OutsideSMSA . . . . . . . . . . . . . . . . . 50 93.3 2.03 2.17 

North Central . . . . . . . . . . . . . . 281 93.1 1.80 1.93 

lnsideSMSA . . . . . . . . . . . . . . . . . . 172 92.8 1.82 1.96 

OutsideSMSA . . . . . . . . . . . . . . . . . 109 93.6 1.77 1.89 

South . . . . . . . . . . . . . . . . . . 318 89.3 1.63 1,83 

lnsideSMSA . . . . . . . . . . . . . . . . . . 162 89.8 1.67 1.86 

OutsideSMSA . . . . . . . . . . . . . . . . . 157 88.8 1.59 1.79 

West . . . . . . . . . . . . . . . . . . . 185 92.0 1.78 1.93 

lnsideSMSA . . . . . . . . . . . . . . . . . . 144 91.9 1.78 1.94 

OutsideSMSA . . . . . . . . . . . . . . . . . 41 92.6 1.76 1.90 

Two children 

Northeast, . . . . . . . . . . . . . . . 214 w 

lnsideSMSA . . . . . . . . . . . . . . . . . . 173 58.9 .96 1,64 

OutsideSMSA . . . . . . . . . . . . . . . . . 47 60.1 .90 1.50 

North Central . . . . . . . . . . . . . . 243 56.5 .98 1.73 

lnsideSMSA . . . . . . . . . . . . . . . . . . 152 58.9 1.03 1.76 

OutsideSMSA . . . . . . . . . . . . . . . . . 91 52.6 .88 1.67 

South . . . . . . . . . . . . . . . . . . 285 53.3 .84 1.57 

lnsideSMSA . . . . . . . . . . . . . . . . . . 143 52.2 .83 1.59 

OutsideSMSA . . . . . . . . . . . . . . . . . 142 54.3 .64 1.55 

West . . . . . . . . . . . . . . . . . . . 158 52.6 .83 1.57 

lnsideSMSA . . . . . . . . . . . . . . . . . . 113 51.8 .81 1.56 

OutsideSMSA . . . . . . . . . . . . . . . . . 45 54.7 .87 1.59 

United States . . . . . . . . . . . . . . 900 

lnaideSMSA . . . . . . . . . . . . . . . . . . 581 

OutsideSMSA . . . . . . . . . . . . . . . . . 319 

32 
Table 14. Average annual number of women who had legitimate births during 19S4-66, percentage expecting to have additional 

children, end average number of additional children expected by all tha mothers and by those expecting to have additional children, 

according to number of living children, geographic region, and metropolitan status of rasidence: United Statas, 1964-66 National 

Natality Survey-Con. 

1 1 , 

Number of living children, Numbar of Percentage 

geographic region, mothers expecting 

additional and metropolitan status (in thousands) children 

Three children 

United States, . . . . . . . . . . . . . . 

inside SMSA . . . . . . . . . . . . . . . . . . 

Outside SMSA . . . . . . . . . . . . . . . . . 

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

Inside SMSA . . . . . . . . . . . . . . . . . . 

Outside SMSA . . . . . . . . . . . . . . . . . 

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

inside SMSA . . . . . . . . . . . . . . . . . . 

Outside SMSA . . . . . . . . . . . . . . . . . 

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

inside SMSA . . . . . . . . . . . . . . . . . . 

Outside SMSA . . . . . . . . . . . . . . . . . 

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

lnsideSMSA . . . . . . . . . . . . . . . . . . 

OutsideSMSA . . . . . . . . . . . . . . . . . 

Four children 

United States . . . . . . . . . . . . . . 

lnsideSMSA . . . . . . . . . . . . . . . . . . 

OutsideSMSA . . . . . . . . . . . . . . . . . 

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

lnsideSMSA . . . . . . . . . . . . . . . . . . 

OutsideSMSA . . . . . . . . . . . . . . . . . 

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

lnsideSMSA . . . . . . . . . . . . . . . . . . 

OutsideSMSA . . . . . . . . . . . . . . . . . 

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

lnsideSMSA . . . . . . . . . . . . . . . . . . 

OutsideSMSA . . . . . . . . . . . . . . . . . 

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

lnsideSMSA . . . . . . . . . . . . . . . . . . 

OutsideSMSA . . . . . . . . . . . . . . . . . 

m 

621 37.9 .55 1.44 

405 37.4 .53 , 1.40 

216 38.7 .59 1.52 

168 42.3 .62 1.47 

124 38.2 .55 1.41 

34 53.6 .86 1.61 

172 40.2 .59 1.48 

106 40.9 .61 1.48 

66 38.1 .57 1.46 

193 34.7 .49 1.41 

105 35.4 .49 1.37 

88 33.8 .49 1.46 

98 32.8 .46 1.40 

70 31.8 .41 1.28 

28 35.2 .58 1.66 

393 21.5 .35 1.61 

258 20.9 .34 1.62 

136 22.7 .37 1.61 

94 23.2 .37 1.59 

77 24.9 .40 1.60 

17 15.6 .23 1.50 

123 23.0 .38 1.66 

78 21.4 .36 1.70 

45 26.9 .41 1.60 

109 21.6 .31 1.46 

55 19.5 .26 1.34 

54 23.7 .37 1.55 

67 16.4 .30 1.88 

47 15.3 .28 1.86 

19 19.0 .36 1.91 

33 
� 

Table 14. Average annual number of women who had legitimate births during 1964-66, percentage expecting to have additional 

children, and average number of additional children expected by all themothers and bythosa expecting tohave additional children, 

according to number of living children, geographic region, and metropolitan status of residence: United States, 1964:66 National 

Natality Survey-Con. 

Number of living children, 

geographic region; 

and metropolitan status 

Five children 

United States . . . . . . . . . . . . . . 

inside SMSA . . . . . . . . . . . . . . . . . . 

Outside SMSA . . . . . . . . . . . . . . . . . 

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

inside SMSA . . . . . . . . . . . . . . . . . . 

Outside SMSA . . . . . . . . . . . . . . . . . 

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

inside SMSA . . . . . . . . . . . . . . . . . . 

Outside SMSA . . . . . . . . . . . . . . . . . 

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

inside SMSA . . . . . . . . . . . . . . . . . . 

Outside SMSA . . . . . . . . . . . . . . . . . 

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

lnsideSMSA . . . . . . . . . . . . . . . . . . 

OutsideSMSA . . . . . . . . . . . . . . . . . 

Six children or more 

United States . . . . . . . . . . . . . . 

lnsideSMSA . . . . . . . . . . . . . . . . . . 

OutsideSMSA . . . . . . . . . . . . . . . . . 

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

lnsideSMSA . . . . . . . . . . . . . . . . . . 

OutsideSMSA . . . . . . . . . . . . . . . . . 

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

lnsideSMSA . . . . . . . . . . . . . . . . . . 

OutsideSMSA . . . . . . . . . . . . . . . . . 

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

lnsideSMSA . . . . . . . . . . . . . ...’.. 

OutsideSMSA . . . . . . . . . . . . . . . . . 

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

lnsideSMSA . . . . . . . . . . . . . . . . . . 

OutsidaSMSA . . . . . . . . . . . . . . . . . 

Avarage number of additional 

Percentage Number of children expected by: expecting mothers 

additional 

(in thousands) All Mothers who 

children 

mothers expect more 

232 23.1 .35 1.51 

152 21.5 .31 1.42 

80 26.2 .43 1.66 

49 20.3 .30 1.48 

41 22.5 .34 1.51 

8 8.5 � 

73 23.0 .38 1.67 

47 21.5 .31 1.43 

26 25.5 .52 2.02 

73 26.7 .39 1.47 

38 20.9 .29 1.38 

35 32.9 .50 1.53 

37 20.0 .26 1.31 

26 20.6 .27 1.30 

11 18.4 .25 1.34 

308 22.7 .39 1.74 

175 21.1 .37 1.78 

133 24.8 .42 1.69 

m .38 I 1.59 

.35 1.51 

.50 1.82 

m112 24.3 .45 1.87 

44 23.5 .52 2.22 

68 24.8 .41 1.65 

37 26.7 .38 1.43 

24 23.0 .30 1.28 

13 33.8 .55 1.63 

I I I 1 

34 
APPENDIX 1 

TECHNICAL NOTES ON METHODS 

Background of This Report 

This report which presents estimates of the 

expectations of additional children of married 

women who had babies in 1964, 1965, or 1966 

is based on data collected in the 1964-66 

National Natalit y Survey. The survey, which was 

conducted by the National Center for Health 

Statistics, was designed primarily to collect 

information on the past and expected future 

fertility of women who were currently bearing 

children. In addition, information on certain 

socioeconomic and demographic characteristics, 

which were thought to be relevant to the study 

of fertility and of infant mortality, was obtained 

from the mother. 

The basic source document was the certificate 

of live birth. Using the information given on the 

birth certificate to determine name, address, and 

legitimacy status, a questionnaire was mailed to 

the mother of each legitimate birth. Additional 

mailings were made if the original questionnaire 

was not returned or was returned with the 

answers to certain questions incomplete. If there 

was no response or if a usable questionnaire was 

not obtained after three mailings, a personal 

interview was attempted by U.S. Bureau of the 

Census interviewers if the mother was a resident 

of a primary sampling unit of the Bureau of the 

Census. 

Although all stages of the survey from questionnaire through final processing were identical 

during the 3 years, each year was an independent survey and was treated as such. Sample 

selection, data collection, and all processing was 

completely independent until the final tape files 

were merged in the computer in order to prepare 

tables for publication. The description of survey 

procedures which follows is written for all 3 

years, but all steps were actually carried out 

separately for each year. 

Sample Design 

The sampling frame for the 1964-66 National 

Natality Survey was the file of microfilm records 

received each month by the National Center for 

Health Statistics from the 54 birth-registration 

areas in the United States. As a general rule, 

each registration area assigns a number to each 

certificate prior to or during the filming of the 

birth record. The certificates are numbered 

consecutively from the first to the last birth 

occurring during the year, 

The sample for the survey was based on a 

probability design which made use of these 

numbers on the birth records. Each 1,000 

records constituted a primary sampling unit. 

Within each 1,000 records, one record was 

chosen at random. Thus a sample of 1 out of 

1,000 births was selected horn the records from 

each registration area. 

The national sample included a total of 4,025 

births in 1964, 3,702 births in 1965, and 3,604 

births in 1966 or 11,331 births for the 3 years 

of the survey. Of these 11,331 births, 647 were 

reported as illegitimate on the birth certificate. 

However, legitimacy status is reported in only 

36 of the 54 registration areas. Hence, a procedure was developed to infer legitimacy status 

on the basis of indirect evidence on the birth 

certificate for the 18 registration areas not 

reporting this item. If the surname of the father 

on the birth record was different from the 

surname of the child or if the surname of the 

father was not reported, the birth was inferred 

to be illegitimate. On the basis of this procedure 

289 births in the sample were inferred to be 

ille#irnate in addition to those reported. 

The mothers of these 936 illegitimate births 

were outside the scope of the survey and were 

not queried. The mothers of an additional 79 

births were not sent questionnaires although 

35 
.

they were within the scope of the survey 

because the State of New Mexico did not 

participate and because nine births in California 

were also in a sample selected by the State. 

Mothers of 10 additional births were not sent 

questionnaires either because their residence was 

outside the United States or because no usable 

mailing address was obtainable, Thus the final 

sample of mothers to whom questionnaires were 

mailed was 10,306. Table I shows the number in 

the original sample drawn from the birth records, the number of mothers of legitimate births 

included in the survey, and the final number of 

mothers to whom questionnaires were mailed. 

The Birth Certificate and Questionnaire 

Facsimiles of the’ Standard Certificate of Live 

Birth and of the questionnaire used in the survey 

are shown in appendix HI. 

Although not all States use the standard 

certificate, most do include the basic information used in this report. The major exception is 

legitimacy status (item 23) which is not re~orted . in- 18 registration areas. The procedure which 

was developed to overcome this omission is 

discussed under Sample Design. 

The questionnaire sent to the mother of a 

legitimate birth was designed primarily to obtain . 

information about her fertility history and her 

expected fertility. Information was obtained on 

the number of pregnancies and the date of birth, 

sex, and present status of the child if the 

pregnancy resulted in a live birth. Information 

on whether she expected to have more children 

and, if so, how many, was also collected. In 

addition, there were questions concerning the 

family income during the previous calendar year, 

the educational attainment of the mother and 

father, and the mother’s employment at any 

time during her pregnancy. A household listing 

provided space for the age, sex, marital status, 

and relationship to the mother of every person 

residing in the household at the time of the 

sample child’s birth. 

Table 1. Total number of births in the United States and the number in the survey of mothers: 1964-66 National 

Item 

Total births in the United 

States . . . . . . . . . . . . . . . . 

Number of births selected in 

thesample . . . . . . . . . . . . . 

Number of illegitimate births 

excluded from survey . . . . . . . 

Number of legitimate births 

in survey . . . . . . . . . . . . . . 

Number of births from New Mexico 

and California . . . . . . . . . . . 

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

Number of births for which questionnaires were mailed . . . . . . . . . 

Natality Survey 

Year 

Total 

1964 1965 1966 

11,394,000 4,027,000 3,760,000 3,606,000 

11,331 4,025 3,702 3,604 

936 282 345 309 

10,395 3,743 3,357 3,295 

79 26 22 31 

10 3 7 

10,306 3,717 3,332 3,257 

36 
Collection of Data 

Data were collected primarily by mail. Using 

the addresses given on the birth certificates, 

questionnaires wei-e mailed to the mothers of 

births which were either recorded as or inferred 

to be legitimate. 

Followup procedures when there was no 

response consisted of a questionnaire sent by 

certified mail 2 weeks after the original mailing 

and a second followup questionnaire sent by 

regular mail 3 weeks after the certified mail. 

When the questionnaire was returned and there 

was no indication of a refusal but certain items 

were either incomplete or inconsistent, either a 

special letter was sent or a telephone call was 

made to obtain the missing data. 

If the mother was a resident of one of the 

primary sampling units designated by the Bureau 

of the Census, a final followup was made by the 

Bureau of the Census interviewers for mothers 

who did not respond or whose responses were 

essent idly incomplete. Because the primary sampling units are geographically selected to give 

unbiased national estimates, such a followup 

sh~uld serve to reduce the bias which might be 

introduced by the nonresponses to a mail 

survey. 

Of the 10,395 legitimate births in the survey 

(including the 89 for whom questionnaires were 

not ‘iiled), questionnaire information was obtained for 9,232, or 89 percent. Approximately 

54 percent of the respondents returned the 

original questionnaire, 31 percent the first (certified) followup, and 7 percent the second followup. The remaining 8 percent were Bureau of 

the Census interviews. 

It should be noted that the response rates to 

the original questionnaire might not have been 

as high if there had been no followups. The 

original questionnaire was sometimes returned 

after the respondent had had time to receive the 

followup questionnaire. And either the original 

or the first followup questionnaire was sometimes returned several weeks after the second 

followup had been mailed. 

Response rates for selected characteristics of 

the mother are shown in table II. 

Processing of Data 

After all the methods of obtaining complete 

questionnaires had been exhausted, the data 

Table II. Numbar of mothers,of Iagitimate births in the survey 

and percent responding by salected characteristics of the 

mother: 1964+6 National Natality Survey 

Characteristic of mother 

All mothers . . . . . . . . . . 

— 

Age

Under 20years . . . . . . . . . . . 

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

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

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

35yearsand over . . . . . . . . . . 

Color 

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

Another . . . . . . . . . . . . . . 

Live-birth order 

First . . . . . . . . . . . . . . . . . 

Second . . . . . . . . .. . . . . . . . 

Third . . . . . . . . . . . . . . . . 

Fourth . . . . . . . . . . . . . . . . 

Fifth orhigher . . . . . . . . . . . . 

Raaion of residence 

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

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

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

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

Metropolitan status 

inside SMSA . . . . . . . . . . . . . 

Outside SMSA . . . . . . . . . . . . 

Number Percentage 

insurvay “esponding 

10,395 88.8 

1,466 82.5 

3,698 88.7 

2,617 90.7 

1,562 90.7 

1,052 90.5 

9,096 89.5 

1,299 84.0 

3,009 88.7 

2,596 89.4 

1,852 89.4 

1,208 89.1 

1,730 87.2 

2,445 92.8 

2,968 91.4 

3,246 87.1 

1.736 82.0 

6,682 90.4 

3,713 85.9 

were edited, coded. and transcribed onto trench 

cards. Basic range edits were made to eli~nate 

punching err”ors, and the cards were then used as 

input for magnetic tape. Computer processing 

included consistency checks, interval edits, estimation or assignment of weights, and imputation of missing data. 

CoWistency checks were made whenever the 

birth record and the questionnaire provided 

information about items which could be 

checked against one another. For example, both 

37 
the birth record and the questionnaire contained 

items about the number of children born alive to 

this mother. In addition, the questionnaire 

provided space for listing the birth date and 

other information about each child. The iterns 

were cross-checked to make certain that no child 

was omitted. 

Interval edits were made wherever two dates 

were given which could reasonably be assumed 

to have some definite relationship or minimum 

or maximum interval between them. For example, if the interval between the mother’s and 

the child’s date of birth was less than 15 years or 

more than 44 years, the record was rejected for 

verification. Similarly, if the interval between 

the birth dates of any two children was less than 

10 months, the record was rejected for verification. 

When a record was rejected because of a 

consistency check or interval edit, the folder 

containing all records on the sample case was 

pulled from the files and gone over carefully to 

ascertain the correct answer. In almost all cases, 

information available on the questionnaire, either 

in answer to questions or in comments which 

the respondent had written voluntarily, made 

the correct answer apparent. In the few remaining cases where the differences could not be 

reconciled, questionnaire items were treated as 

nonresponies and were imputed at that stage of 

the processing. 

Nonresponse and Imputation for Missing Data 

Failure to obtain a response represents one of 

the main sources of error and bias in any data 

collection system. Data must be imputed for 

persons for whom the information is unknown 

in order to use the data at all. Often the user of 

the data merely assumes that the persons for 

whom the information is unknown are exactly 

like those for whom it is known. Instead, the 

imputation for the National Natality Survey was 

done as part of the processing by taking advantage of available information. This insured that 

imputed data for nonrespondents are the same 

as that for “similar” respondents, rather than for 

all respondents. 

Imputation was done first for unit nonresponses. Unit nonresponse in this survey is 

defined as failure to mail a questionnaire to the 

mother of a legitimate birth for any of the 

reasons given at the beginning of this appendix, 

failure to obtain a returned questionnaire after 

all followup procedures had been completed, 

and failure to obtain a usable questionnaire even 

though the form was returned. Out of the 

10,395 legitimate births selected’ in the sample, 

1,163 or 11 percent were classed as unit 

nonresponses. 

The number of sample cases and the proportion which were classed as unit nonresponses are 

shown by color and age of mother in table III 

and by color and live-birth order in table IV. 

Age of mother, live-birth order, and color of 

mother are all characteristics which could be 

expected to influence the mother’s responses to 

items on the questionnaire such as number. of 

children expected. They are also characteristics 

which are recorded on the birth certificate and 

are therefore available for all sample cases 

Table I I 1. Number of mothers of legitimate births in the survey and the nonresponse rates by age and color of mother: 1964-56 

National Natality Survey 

. 

Age 

Alleges . . . . . . . . . . . . . . . . . . 

Under 20 years . . . . . . . . . . . . . . . . . 

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

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

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

35years And over . . . . . . . . . . . . . . . . 

Total White 

Number Percent Number Parcent 

in survey nonrasponse in survey nonrasponse 

10,395 11.2 9,086 10.5 

1,466 17.5 1,235 16.8 

3,698 11.3 3,258 10.5 

2,617 9.3 2,315 8.5 

1,562 9.3 1,389 8.9 

1,052 9.5 919 9.2 

All other 

= 

1,299 I 16.0 

231 20.8 

440 16.8 

302 15.6 

193 12.4 

133 11.3 

38 
Table IV. Number of mothers of legitimate births in the survey and the nonresponse rates by live-birth order and color 

of mother: 1964-66 National Natality Survey 

Total White All other 

Birth order Number Percent 

Percent 

Number 

Percent 

Number non- non- in survey nonresponse in survey response 

in survey esponse 

All birth orders . . . . . . . . . . 10,395 i 11.2 9,096 10.5 1,299 16.0 

First . . . . . . . . . . . . . . . . . . . 3,009 

Second . . . . . . . . . . . . . . . . . . 2,596 

Third . . . . . . . . . . . . . . . . . . . 1,852 

Fourth . . . . . . . . . . . . . . . . . . 1,208 

Fifth and higher . . . . . . . . . . . . . 1,730 

whether these cases represent respondents or 

nonrespondcnts. For ti”ese reason:, the three 

characteristics were chosen for use in unit 

imputation as well as estimation. 

Imputation was done in the computer by 

setting up a matrix of 24 color, age, and 

live-birth order classes (shown in the section on 

Estimation), the cells of which were filled as 

each record meeting the criteria pas sed through. 

As the file of records was processed, the 

information in each cell was replaced by that 

from the next record which met the specifications. When a record for which no questionnaire 

information was available was read in, i.e., a unit 

nonresponse, the data already in the appropriate 

cell were imputed to that record. 

In addition to unit ncmresponses, there were 

also item nonresponses. Item nonresponse is 

defined as no information available on a particular item because of omission, illegibility, or 

refusal even though the questionnaire was complete enough to be considered a unit response. 

In general, item nonresponse rates were very 

low–less than 1 percent. Most of the item 

nonresponses were imputed on the basis of 

information available elsewhere on the birth 

certificate e or questionnaire. For example, 

11.3 2,734 10.8 275 16.0 

10.6 2,315 9.6 281 18.1 

10.6 1,643 9.8 209 17.2 

10.9 1,069 10.3 139 15.8 

12.8 1,335 12.4 395 13.9 

mother’s age as recorded on the birth certificate 

was used t= compute her year of birth when she 

had not completed that questionnaire item. 

Other items with very low nonresponse rates 

(less than 0.5 percent) were imputed arbitrarily. 

Five items with fairly high nonresponse rates 

were imputed in the computer by procedures 

similar to those used for unit imputation on the 

basis of matrices designed specific for each item. 

Completed weeks of pregnancy were imputed 

using birth weight and race; expectation of more 

children by using age of mother and whether 

any children were expected; education of father 

by using age of father and education of mother; 

and family income by using age and education 

of father. 

Item nonresponse rates for iterns used for this 

report are shown in table V. 

Estimation 

Published statistics based on the survey are 

national estimates prepared by the use of a 

poststratified ratio estimation procedure. The 

purpose of ratio estimation is to take into 

account available relevant information, thcreb y 

reducing the variability of the estimate. The 

39 
Table V. Item nonresponsa rates for statistics shown in this Color and age Live-birth order 

report: 1964-66 National Natality Survay 

White 

Itern Uumber aercent 1 . . . . . . .. . . . .. Under 20 years 1


2 . . . . . . . . . . . . . Under 20 years 2+ 

Ageofmotherl . . . . . . . . . . . . . . 3 0.0 

Raceofmotherl . . . . . . . . . . . . . 7 0.1 

Sexofchildl . . . . . . . . . . . . . . . 1 0,0 

Number of previous children born alive 

Nowlivingl . . . . . . . . . . . . . 43 0.4 

Nowdeadl . . . . . . . . . . . . . 199 1.9 

Number of fetal deathsl . . . . . . . . . . 310 3.0 

Employment during pregnancy2 . . . . . 13 0.1 

Yaar of first marriage2 . . . . . . . , . . 35 0.4 

Education of mother2 . . . . . . . . . . . 15 0.2 

Education of father2 . . . . . . . . . . . 78 0.8 

Family income2 . . . . . . . . . . . . . . 231 2.5 

Whether additional children are 

expected . . . . . . . . . . . . . . . 73 0.8 

Number expected2 . . . . . . . . . 378 4.1 

Sex of previous child3 . . . . . . . . . . . 17 0.0 

18ase: 10,395 legitimate live births. 

2 Base: 9,232 unit responses. 

3 Base: 26,177 children reportad. 

relevant information used in the 1964-66 National Natality Survey was age and race of 

mother and live-birth order of child. These three 

items are recorded on the birth certificate, and 

statistics showing the national totals (based on a 

50-percent sample) are published annually by 

the Division of Vital Statistics, National Center 

for Health Statistics.8 

The birth certificates were first checked to be 

certain that these iterns were complete on all 

records. When they were not, the items were 

imputed by hand, taking advantage of the 

information available on the questionnaire of a 

respondent and of all other items on the birth 

certificate of a nonrespondent. It was necessary 

to impute race of mother for seven records, age 

of mother for three records, and live-birth order 

for 242 records. 

All certificates were classified as belonging in 

one of the following 24 groups: 

40


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


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


5 . . . . . . . . . . . . .


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


7 . . . . . . . . . . . . .


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


9 . . . . . . . . . . . . .


lo . . . . . . . . . . . ... 

11 . . . .. . . . . . . .


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


13 . . . . . . . . . . . .


14 . . . . . . . . . . . .


15 . . . . . . . . . . . .


16 . . . . . . . . . . . .


17 . . . . . . . . . . . .


18 . . . . . . . . . . . .


19 . . . . . . . . . . . .


20 . . . . . . . . . . . .


21 . . . . . . . . . . . .


22 . . . . . . . . . . . .


23 . . . . . . . . . . . .


24 . . . . . . . . . . . .


20-24 yaars 

20-24 years 

20-24 years 

25-29 years 

25-29 years 

25-29 yaars 

25-29 yaars 

30-34 years 

30-34 years 

30-34 years 

35 years and over 

35 vears and over 

All other 

Under 20 years 

Under 20 years 

20-24 years 

20-24 years 

25-29 years 

25-29 years 

25-29 years 

30-34 yaars 

30-34 years 

35 years and over 

1


2


3+


1


2


3-4


5+


1-2


34


5+


1-4


5+ 

1


2+


1-2


3+


1-2


3-4


5+


14


5+


All 

For each group, the ratio of the number of 

births in the United States in 1964, in 1965, and 

in 1966 estimated from the 50 percent sample 

to the number of births selected for the National 

Natality Survey (NNS) sample in each year was 

calculated. These 24 ratios for each year were 

the sample weights used in estimating national 

totals. In addition, for each of the same 24 

groups, the ratio of births in the United States 

during the combined 3 years to the number of 

births selected in the National Natality Survey 

during the same 3 years was calculated so that 

statistics could be published on the annual 

average number of births in 1964-66. 

The effect of the ratio adjustment is to make 

the estimate from the National Natality Survey 

sample consistent with the estimate based on the 
50 percent sample for each of the groups used in 

the estimation procedure. However, since data 

published from the 1964-66 National Natality 

Survey include only legitimate births, the published statistics are not the same as those in Vital 

Statistics of the United Statess which include all 

births. 

Thus, estimates of characteristics are produced from the NNS using the following formula: 

24 

x;=I ~ Yi 

+, ‘i 

where 

X; is the estimate of the number of births 

with a particular characteristic in group i, 

xi is the count of sample births with the 

characteristic in group ~ 

YQ the count of all s~mP1ebirths in 90UP ~$ 

Yi is the total ,number of births in group i, 

based on the 50-percent sample. 

Reliability of Estimates 

Since the statistics derived from this survey 

are estimates based on a sample, they may’ differ 

from the figures that would have been obtained 

had a complete count been made using the same 

questionnaire and procedures. 

The probability design makes possible the 

calculation of sampling errors. The standard 

error is a measure of the sampling variation that 

occurs by chance because only a sample rather 

than the entire population is surveyed. The 

chances are about 68 out of 100 that an 

estimate from the sample differs from the value 

for the entire population by less than one 

standard error. The chances axe about 95 out of 

100 that the difference is less than twice the 

standard error and about 99 out of 100 that the 

difference is less than three times the standard 

error. 

Estimates of sampling variability for the 

statistics derived from- thi= survey were based on “ 

20 random half-sample replications. This technique yields overall variability through observation of variability among random subsamples of 

the total sample. It reflects both the error that 

arises rom sampling and a part of the measurement error, but it does not measure any systematic biases in the data. A general discussion 

of the development and evaluation of a replication technique for estimating variance has been 

published elsewhere.9 However, the procedures 

and computations required to estimate variances 

by this method for the National Natality Survey 

are briefly described below. 

Each record from the entire file of records in 

the survey was assigned systematically to a 

group numbered at random from 1 through 40. 

Twenty pairs of random groups were created 

from these groups. A half sample was formed by 

randomly selecting one group from each of the 

20 pairs. This process was repeated until 20 

“replicate half samples” were formed from 

which variance estimates were derived. The 

composition of the 20 half samples was determined by an orthogonal plan. 

After the composition of each of the half 

samples was determined, all the estimation 

procedures used to produce the final estimates 

for the entire sample were applied separately to 

each of the resulting half samples. 

An estimated variance S’ of an estimated 

statistic x’ of the parameter ‘X was obtained by 

applying the folIowing formula: 

where 

x’ is the estimate of X based on the entire 

sample, and 

x“ is the estimate of X based on half sample 

i 

Rules to determine the approximate standard 

errors for estimates presented in this report are 

as follows: 

1. Estimates of aggregates. —Approximate 

standard errors for estimates of aggregates, 

41 
such as the number of mothers who were 

high school graduates, are given in table VI. 

2. Estimutes of percentages in a percent 

distribution. –Approximate standard errors 

for estimated percentages, such as proportion of mothers who expected to have 

additional children, are determined in one 

of the two following ways, depending upon 

the source of the base of the percentage: 

a.	 when the denominator i; an es&nate 

from the sample which is not one of the 

ratio estimation cells shown on page 40, 

the approximate standard errors are 

given in table VII. 

b.	 when the denominator is one of the 24 

rat io estimation cells and is therefore not 

subject to sampling error, the relative 

standard error of the percentage is equivalent to the relative standard error of the 

numerator, which is given in table VI. 

3. Estimates of rates. –Approximate standard 

errors	 for estimated rates, such as average -.. 

Table VI. Approximate standard errors of aggregates: 1964-56 

National Natality Survey 

Relative 

standard Standard Annual estimate error error 

percent 

5,000 . . . . . . . . . . . . . . . 28.8 1,490 

10,000 . . . . . . . . . . . . . . . 19.6 1,960 

15,000 . . . . . . . . . . . . . . . 14.8 2,220 

20,000 . . . . . . . . . . . . . . . 12.2 2,440 

25,000 . . . . . . . . . . . . . . . 10.9 2,725 

50,000 . . . . . . . . . . . . . . . 7.5 3,750 

75,000 . . . . . . . . . . . . . . . 6.0 4,500 

100,000 . . . . . . . . . . . . . . . 4.9 4,910 

150,000 . . . . . . . . . . . . . . . 3.9 5,850 

200,000 . . . . . . . . . . . . . . . 3.3 6,600 

250,000 . . . . . . . . . . . . . . . 2.8 7,175 

300,000 . . . . . . . . . . . . . . . 2.5 7,590 

500,000 . . . . . . . . . . . . . . . 2.0 10,100 

700,000 . . . . . . . . . . . . . . . 1.8 12,670 

1,000,000 . . . . . . . . . . . . . . . 1.3 13,200 

number of children per mother, are determined in one of the two following ways, 

depending upon the source of the base of 

the rate: 

a.	 when the denominator is an estimate 

which is not one of the cells used in ratio 

estimation, the approximate standard 

errors are given in table VIII. 

b.	 when the denominator is one of the 24 

ratio estimation cells, the relative standard error of the rate is equivalent to the 

relative standard error of the numerator 

which is given in table VI. 

4. Difference between two sample 

estimates. —The standard error of a difference is approximately the square root of 

the sum of the squares of the standard 

errors of the two estimates. This formula 

will represent the actual standard error 

quite accurately for the difference between 

rno thers with separate and uncorrelated 

characteristics, although it is only a rough 

approximation in cases where the characteristics are correlated. 

In addition to sampling errors, survey results 

are subject to errors in conceptual formulation, 

ambiguities in definitions and in the wording of 

questions, biases due to nonresponse or incomplete response, and errors in coding, editing, and 

tabulation. There is no way of computing the 

magnitude of these errors. However, they were 

minimized as far as possible. 

Errors in conceptual formulation and ambiguities were reduced by pretesting the questionnaire before the survey be@n. The steps 

taken to reduce biases due to nonresponse were 

discussed in the sections on data collection and 

imputation. Errors in coding and editing were 

reduced by verification and the consistency and 

interval checks discussed in the section on 

processing the data. Errors in tabulation were 

reduced, if not eliminated, by carefully crosschecking the tabulations and by comparing data 

from this survey with data from other sources 

when available. 

%andardiziztion 

Standardization was done by the direct 

method, using the total number of mothers as 

the standard population. 

42 
Table VI 1. Approximate standard errors for percentages: 1964-66 National Natality Survey 

Estimated percent 

Base of percentage 2 5 10 20 25 30 

or 98 or 95 or 90 or 80 or 75 or 70 Ono 50 

Standard errors expressed in percentage points 

30,000 . . . . . . . . . . . . . . . . . . . . 1.5 2.3 3.2 4.2 4.6 4.8 5.2 5.3 

50,000 . . . . . . . . . . . . . . . . . . . . 1.1 1.8 2.4 3.3 3.5 3.7 4.0 4.1 

100,000 . . . . . . . . . . . . . . . . . . . . 0.8 1.3 1.7 2.3 2.5 2.6 2.8 2.9 

250,000 . . . . . . . . . . . . . . . . . . . . 0.5 0.8 1.1 .1.5 1.6 1.7 1.8 1.8 

500,000 . . . . . . . . . . . . . . . . . . . . 0.4 0.6 0.8 1.0 1.1 1.2 1.3 1.3 

1,000,000 . . . . . . . . . . . . . . . . . . . . 0.3 0.4 0.5 0.7 0.8 0.8 0.9 0.9 

2,000,000 . . . . . . . . . . . . . . . . . . . . 0.2 0.3 0.4 0.5 0.6 0.6 0.6 0.6 

3,000,000 . . . . . . . . . . . . . . . . . . . . 0.1 0.2 0.3 0.4 0.5 0.5 0.5 0.5 

4,000,000 . . . . . . . . . . . . . . . . . . . . 0.1 0.2 0.3. 0.4 0.4 0.4 0.4 0.5 

— 

Table Vlll. Standard error ofnumber ofchildren permother: 1964-66 National Natality Survey 

Numberofchildren 

Average annual 

number of mothers 

1 2 3 4 5 

500,000 .04

Standard error expressed in number of children 

25,000 . . . . . . . . . . . . . . . . . .13 .17 .21 .25 .29 

50,000 . . . . . . . . . . . . . . . . . .10 .14 .16 .19 .22 

75,000 . . . . . . . . . . . . . . . . . .08 .09 .11 .12 .13 

100,000 . . . . . . . . . . . . . . . . . .08 .09 .09 .10 .11 

150,000 . . . . . . . . . . . . . . . . . .06 .07 .07 .08 .08 

200,000 . . . . . . . . . . . . . . . ,. .05 .05 .06 .06 .07 

. . . . . . . . . . . . . . . . . .03 J.04 .05 .05 

Rounding of Numbers 

aggregates are rounded to the nearest thousand 

The original tabulations on which the data in although they are not necessarily accurate to 

this report are based show figures to the nearest that detail. AII percentages, ratios, and averages 

whole unit. In the published tables, estimates of were computed using unrounded figures. 

43 
APPENDIX II 

CERTAIN TERMS USED IN THIS REPORT 

Information From the Cetiificate of Live Birth 

Race ofmother. –Race is recorded or derived 

from entries on the birth certificate. Negro is 

used as recorded. The category “white” includes 

white, Mexican, or Puerto Rican. The category 

“all other races” @eludes American Indian, 

Chinese, Japanese, Aleut, Eskimo, Hawaiian, or 

part-Hawaiian. 

Color. –Color is recorded or derived from 

entries on the birth certificate. The category 

“white” includes white, Mexican, or Puerto 

Rican. The category “all other” includes Negro, 

American Indian, Chinese, Japanese, Aleut, 

Eskimo, Hawaiian, or part-Hawaiian. Color is 

used only in appendix I. 

Region of residence. –States are grouped into 

four regions which correspond to the regions 

used by the U.S. Bureau of the Census. The 

regions are as follows: 

&!3EI! States Included 

Northeast . . . . . . .	 Maine, New Hampshire, 

Vermont, Massachusetts, 

Rhode Island, Connecticut, 

New York, New Jersey, 

Pennsylvania 

North Central . . .	 Ohio, Indiana, Illinois, 

Michigan, Wisconsin, Minn esota, Iowa, Missouri, 

North Dakota, South 

Dakota, Nebraska, Kansas 

South . . . . . . . . . .	 Delaware, Maryland, District of Columbia, Virginia, 

West Virginia, North Carolina, South Carolina, 

Georgia, Florida, Kentucky, Tennessee, Alabama, Mississippi, Arkansas, Louisiana, Oklahoma, 

Texas 

West . . . . . . . . . . . Montana, Idaho, Wyoming, 

Colorado, New Mexico, 

Arizona, Utah, Nevada, 

Washington, Oregon, California, Alaska, Hawaii 

Metropolitan status of residence. –Usual residence of mother of infant is classified by 

location in metropolitan or nonmetropolitan 

areas. Metropolitan areas are standard metropolitan statistical areas (SMSA’S) defined by the 

U.S. Office of Management and Budget and used 

by the U.S. Bureau of the -Census. In New 

England, metropolitan State economic areas are 

used in place of SMSA’S. 

Age of mo ther. –Age of mother is recorded or 

derived from entries on the birth certificate. It 

refers to the mot her’s age at the time of the 

sample child’s birth. 

Le#”timacy status. –For the reporting States, 

legitimacy is recorded or derived from the entry 

on the birth certificate. For States not reporting 

legitimacy on the birth record, it is inferred 

from other evidence on the certificatee as, for 

example, mother, father, and child all with the 

same last name, and mother’s maiden name is 

different. Legitimacy status is reported in 36 of 

the 54 registration areas in the United States. 

Information From the Questionnaire 

Living children. –All of the mother’s own 

children whom she reported as live births but for 

whom no date of death was reported were coded 

as living at the time of the sample child’s birth. 

The sample child was always coded as a living 

child. 

44 
Expectation of additional children. -Coded 

directly as the response to the question: “In 

your case, do you expect to have more children?” with four possible responses of “Definitely yes, “ “Probably yes,” “Probably no,” 

“Definitely no. ” 

Number of children expected. –Coded from 

the number reported by mothers who responded 

“Definitely yes” or “Probably yes.” All numbers 

were coded as integers with the lower number 

reported if a range of one and the middle if a 

range of two. Mothers who responded “Definitely no” or “Probably no” were coded to 

zero. 

Intervals. –All intervals were computed by 

converting the dates of birth, marriage, or death 

into the number of months since January 1, 

1900, and subtracting one date from the other. 

Measures computed in this manner include 

mother’s age at first marriage, interval from first 

marriage to sample child, and interval from 

preceding birth to sample child. 

First murriage.–Defined by the mother’s own 

response to the question. If her present marriage 

was the first marriage, she was asked to record 

the month, day, and year of her marriage. If her 

present marriage was not her first marriage, she 

was asked to record the month, day, and year of 

her first marriage and her present marriage. All 

data in this report are based on her first 

marriage. 

Preceding child –Defined as the child, 

whether living or not, whose date of birth 

immediately preceded that of the sample child 

when all the children born alive to this mother 

were ranked by date of birth. If the sample child 

was the second (or later) cldd of a multiple 

birth, the preceding child was the first (or 

second) child of that birth. 

Dates of birth. –Dates of birth of all members 

of the household were recorded in the household listing and of all the mother’s children who 

were not members of the household in speeific 

questions. AU dates were recorded by month, 

day, and year. 

Infant death. –Defined as a child born alive 

who died before his first birthday. If the interval 

in months between the date of birth and the 

date of death was less than 12, the child was 

coded as an infant death. 

Fetal death. –Defined by the mother’s response that she had had one or more miscarriages and/or babies born dead. 

Sex of children. –Recorded on the household 

listing or the specific questions for children who 

were not living in the household. 

‘Mother’s age at first mam”age.–Defined by 

the interval in months between her date of birth 

and date of first marriage. The intervals in 

months were converted into years of age. 

Famz”ly income. –Defined as the total income 

during the calendar year preceding the birth of 

the sample child received by all members of the 

family who were living in the same household as 

the mother at the time of the birth of the 

sample child. 

Level of educational attainment. –Defined as 

the highest grade of regular school completed. 

Employment status. –Defined by employment 

outside the home at any time during the 

pregnancy which resulted in the birth of the 

sample child. 

45 
APPENDIX Ill 

SOURCE FORMS 

Certificate of Live Birth 

Form .m.r.vd,
 Buds,t Buren. No. IIS-BS74S.


CERTIFICATE Or LIVE BIRTH STATE OF BIRTH No, 

I. PLACE OF �IRTH .2. $S$T41+ERESIDINCC OF MOTHER ~W’&:N:s mofhcr UOc?) 0. mumv 

: k CITY. TOWN, OR LOCATION c. CITY, TOWN, OR LOCATION g 

& I 

g c. NAME OF (IJ ml h Msplfd, obc #lresf addrc8#) d. STREETAOORESS HOSPITALOR 

i lNSli iUTICN 

u d, IS PLACEOF EIRTN INSIOECITY LIMITS? e. IS RESIDENCEINSIDECITY LIMITS? [/. IS RESIDENCEOfl A FARMI 

u 

5 4. SEX %, THIS CNRTN $b. IF TWIN OR TRIPLET, WAS CNILO CORN 6, OATE hfowh Da# Yew 

SINGLE o TWIN O TRIPLET � 1ST � 200 30a Bly7H . . 

7. NAME #wJt MlddEc - lzw 8. COLOROR RACE, u ~ 

f? 

g! g ‘9, AGE (Al,i~ of ~h& bf,l~) 10. BIRTHPLACE (dVeEeor foreign Couniq) 1la. USUALCCCUPATON I lb. KINO OF BUSINESSOR INOUSTRY 

C$ YEARS 

al= 

pj b “ = 12. MAIOEN NAA4E FM Middle Lad 13, COLOROR RACE 

i ~: 9 

2 J g t4, AGE (Al lfnlc .f {Ah birth) !s, BIRTHPLACE(StaEe or Jordan cM@r#) 16. PREVIOUSDELIVERIESTo MoTHER (2% NOT lIN4udethb birth) 

; YEARS — - ., Mm ma”” b, Maw -W OTHER chU- ,. Hew mm !clal dmlA* OTHER ahild?m d“. w,m bun din 6.( .,, l/,lw, In,. dead .1 A .V Y ..w ~j ‘TiNEOESMAS4T .“ “m Ii,i”#?d,td? dim .ft4r mwtuion) ? 

Oa 

$ z 18. MOTNER’S MAILING AOORESS 

~ g“ 

!60. SlaNATURC 18b, AITENOANT AT BIRTH 9

J 1 Asreb# ctti D 

Ihti lhJ4 EA f d M, 0,0 D. O. a. MIOWIFE � OTHER (S@Jr) waa born aEbe s x- yf:tidatg W. AODRE3S 

* 

16d, OATESIGNEO 

3 I z 19. DATE RECO. BY LOCALREG. 20. REGISTRARS SIGNATURE 21, OATSON WHICH GIVEN NAME AOOEO 

b BY (RcPi#trar) 1-

%1 POR R4COEOAL ANO S4SALTMUBBOSSLW = 

~ (Tkti #sclion MUST & flUcd OUA)

~ 220. LENG7N OF PREGNANCY 22b. WEIGNT AT SIRTH 23. LEGITIMATE 

B ~E:&TEO LB. oz. YES � NO � I 

7

= (SP&X FCR AOOtTIOA 0?ASECKALANG NEALTH ITSAESSY lNOIVICUAL STATSS) s 

: I 
Informant Questionnaire 

DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE 

PUBLIC HEALTH SERVICE 

WASHINGTON. D.C. -l 

NATIONAL CENTER POk 

IWALTIS STATISTICS 

1-

L 

TM U. S. FublicHealthServiceis conductinga natimal studyof families 

havingbabiesduring1966. In this study,we are particularlyinterested 

in learningaboutthe sizeand typssof thesefamilies,as well as about


otherfamilycharacteristics.This informationis neededin orderto


betterunderstandthe grovthsnd changestak~ placein our population.


Detailedand accurateinformationof thistype is essentialfor intelligent


planningof programsto improvethe NationIshealthand welfa=.


Thisnationalstudywill be based cm informatim obtainedfrau families


whichwere selectedas a samplefrcm amongthe 4 millionfamilieshavinga


baby during1966. Your femllywas one of those selected. Pleaseanswer


the qpestionson the followingpagesend zwturnthis fozm in the enclosed


postage.fmse
envelope.


As you mightexpect,statisticalaccuracyrequiresthatwe receiveyour 

mpl.yand thoseof all of the other,f~l.iesin the study. you may be 

assmd that all infonuationwhich you reportaboutyourselfand your femily


willbe kept ccmplstelyconfidentialin acco~ce with regulaticm of the


U. S. PublicXealthService. Your cooperationin this study,which seeks 

infomatica of importancefor the general welfare,is appreciated. 

I#u’oe G. SMzei, Ph. D. 

Chief,Divisionof Health 

Reco?sistatistics


NsmeofChild


DateofBirth FNeNumber


,


66M


47 
CWFIOWTIUllY ha- ba@m �-curd thm Individual � s Publ i-hod In thq Fdor.1 Raoist.r May 20. 19S9 

?c.rm Approved 

Budaet BurmmI No. 68-R823 

NATIONAL BIRTH SURVEY 

PART 1. INFORMATION ABOUT YOUR CHILDREN 

In this part, we aye interested in knowing about aU of 

the childyen which have ever been born to you, even if 

they were by a pvevious marriage. 

How many babies have you ever had? (Count all 4. Have you ever had any babies that were born 

those that were born alive to you at any time.) dead? 

� l � 4 � 7 � 10 or more � NO 

� 2 � 5 08 

1 

Number 

� YES ~How many have you ever hay 

Number � 3 � 6 � 9 

.	 Have you ever had any children who have died? 5. Have you ever had a miscarriage? (Do not count miscarriages or babies that were 

born~ead.) � NO 

� NO H YES--HOw many have you ever had? 

1 

� YES-Please list below the name, sex, date Number 

of birth, and date of death of each 

such child. 

! 

Name of child Sex Birth Death families are completed, while others expect more 

children. In your case, do YOUexpect to have 

more children? 

� Definitely yes How many more 

- children do you 

Date of Date of 6. After each birth, some couples feel that their 

3.	 Were any of your children fiving away from you � Probably yes I think you will 

when your last baby was born ? (For example, probably have? 

in the Armed Forces, living with relatives, etc.) � Probably no 

� NO l_’JDefinitely no 

� YES--Please list below the name, sex, and & 

date of birth of each such child. 

+ 

Date of 

Name of child Sex Birth 

vis. 442s - 19 (P.s. 2) (GO ONTO PART If) - KEv, w{, 

4s 
PART Il. INFORMATION ABOUT YOUR FAMILY 

In this part, information is asked about the members of the family who 

lived with you when your lastbaby was born. 

L	 Lkt below everyone who usually lived in your household at the time your last baby was born. Be sure 

to list yourself, your husband (if he lived at home) and your newborn baby, as well as other children 

and relatives living with you. Unrelated persons who lived with you, and children who were away at 

school or college, should be listed. Do not include persons who lived away. (For example, persons 

in the Armed Forces). Also, include persons who were only visiting temporarily at the time 

your baby was born. 

Enter your name on the first line; For each person, provide the information requested below. 

enter the names of every other Relationship to you MaritaI Status (for 

person who lived with you, including (husband, daughter, Date of birth persons 14 years 

your newborn baby, on the following son, father-in- law, and older). 

lines. nephew, stepson, Married JXvorced 

adopted daughter, Month-Day-Year Widowed Separated 

:First name? (Last name) etcJ I kwzle (never married 

Yourself I I 

1 I 

(If more spat is needed, please continue on separate sheet) 

3. What was the total income of your family during 1965? 

2.	 Who was the head of your (Include all income of all members of the family listed above even 

household? if they not living together during 1965. Include income from

� Your husband 

� Another person 

I 

I Name of head 

4S-4425- 19 (Pam 3) 

EV. 3/C4 

were 

all sources such as wages, salaries, unemployment compensation. 

help from relatives, profita and fees from own business or farm, 

welfare payments, Social Security payments, etc.) 

� None � $4000-$4999 

� Under $1000 � $5000-$6999 

� $1000-$1999 � $7000-$9999 

� $2000-$2999 •1 $10,000-$14,999 

•1 $3000-$3999 •l $15,000 or over. 

(GO ON To PART UI) ~ 

49 
--------------

--------------

--------------

------------------

~ART 111.INFORMATION ABOUT YOURSELF PART Ill. Con. 

AND YOUR HUSBAND 

In this part, information is requested about 4. What was the highest grade (or year) of regular 

you and your husband. school thst your husband ever attended? 

1.	 Is this your first marriage? 

(Circle highest grade attended) 

~ YES , 

Please give the date of None -------------------- O 

your marriage. Elementary 1 2 3 4 5 6 7 8 

- 4a”z-:::’:;;6+”N0 

PART IV. INFORMATION ON 

o NO HEALTH INSURANCE 

In this part, we are interested in finding out u,hethev 

you were covered by health insurance atany time duriw Your recent Pregnancy. Please report on each kind 

of health insurance protection which you had, wJLether 

G. Ovnot the insurance was used. 

1. During your recent pregnancy, did you have health 

Please give the date of insurance to pay for doctor?s bills for office 

present marriage. visits or home calls? 

2. Dld you have health insurance to pay for hospital 

F careat~~~~ofdeliv~y~ 

Z. Were you employed outside your home at any 

time during your recent pregnancy ? � YES n NO 

O YES _ When did you stop working before 3. Did you have health insurance to pay for the 

your baby was born? doctor’s bill for delivexy of your baby? 

“N” + PART::&:;:P~~T,N~ 

3.	 What was the highest grade (or year) of regular THIS FORM 

school that you ever attended? 

Name of person completing this form 

(Circle highest grade attended) 

None -------------------- O Address


Elementary 1 2 3 4 5 6 7 8


High School 1 2 3 4


College 1 2 3 4 5 6+


3a. Did you finish this grade ? � YES O NO	 Telephone 

Number 

;OMMENTS: 

PSS.4425-IP 

raw. M% (Pue 6 GPO035.,,6 

50 * U. S. GOVERNMENT PRINTING OFFICE :1973 515-214/63 
VITAL AND HEALTH STATISTICS PUBLICATION SERIES 

Formerly Public Health Service Publication No. 1000 

Series 1.	 Programs and collection procedures. — Reports which describe the general programs of the National 

Center for Health Statistics and its offices and divisions, data collection methods used, definitions, 

and other material necessary for understanding the data. 

Series 2.	 Data evaluation and methods research. —Studies of new statistical methodology including experimental tests of new survey methods, studies of vital statistics collection methods, new anal~ytical -

techniques, objective evaluations of reliability of collected data, contributions to statistical theory. 

Swies 3. .4nalvtical 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. 

Swies 4. Documents aria’ committee repovts. —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. 

Sen”es 10.	 Data porn the Health Interview Swwev. —Statistics on illness, accidental injuries, disability, use 

of hospital, medical, dental, and other services, and other health-related topics, based on data 

collected in a continuing national household interview survey. 

Series 11. Dab jkom the Health Examination Survey. —Data from direct examination, testig, and measurement of national samples of the civilian, noninstitutional population provide the basis for two types 

of reports: (1) estimates of the medically defined prevalence of specific diseases in the United 

States and the distributions of the population with respect to physical, physiological, and psychof	 logical characteristics; and (2) analysis of relationships among the various measurements without 

reference to an explicit finite universe of persons. 

Series 12. Data from the Institutional Population Surveys —Statistics relating to the health characteristics of 

persons in institutions, and their medical, nursing, and personal care received, based on national 

samples of establishments providing these services and samples of the residents or patients. 

Series 13.	 Data jkom the Hospital Dischavge Survey. —Statistics relating to discharged patients in short-stay 

hospitals, based on a sample of patient records in a national sample of hospitals. 

Series 14.	 Data on health resources: manpower and facilities. —Statistics on the numbers, geographic distribution, and characteristics of health resources including physicians, dentists, nurses, other health 

occupations, hospitals, nursing homes, and outpatient facilities. 

Series 20.	 Data on mortality.— Various statistics on mortali~ other than as included in regular anrmal or 

montrdy reports—special analyses by cause of death, age, and other demographic variables, also 

geographic and time series analyses. 

S.97z”es21.	 Data on natality, mawiage, and divoyce. —Various statistics on natality, marriage, and divorce 

other than as included in regular annual or monthly reports+pecial analyses by demographic 

variables, also geographic and time series analyses, studies of fertility. 

Sem”es 22.	 Data jrom the National Nakzlity and Mortality Surveys. — Statistics on characteristics of births 

and deaths not available from the vital records, based on sample surveys stemming born these 

records, including such topics as mortali~ by socioeconomic class, hospital experience in the 

last year of life, medical care during pregnancy, health insurance coverage, etc. 

For a list of tities of reports published in these series, write to: Office of Information 

National Center for Health Statistics 

Public Health Service, HSMHA 

Rockville, Md. 20852