FROM VITAL & HEALTH STATISTICS OF THE NATIONAL CENTER FOR HEALTH STATISTICS 

U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE � Public Health Service ~ Number 43 � December 1Z, 197s 

Use of Intrauterine Contraceptive Devices in the United Statesq 

INTRODUCTION 

About 6 percent of the married women and 

about 9 percent of the widowed, divorced, and 

separated women were using an intrauterine contraceptive device (IUD) as of 1976. The Lippes 

Loop was the most popular IUD, followed by 

the Copper 7. 

The data presented in this report are the first 

national estimates of the use of intrauterine contraceptive devices, by type of device, from the 

1973 and 1976 National Surveys of Family 

Growth conducted by the NationaI Center for 

Health Statistics. The data were collected by 

means of personal interviews with a multistage 

probability sample of women 15-44 years of age 

in the household population of the conterminous United States. Women were eligible 

for inclusion in the sample if they were currently or previously married or were never 

married but had offspring presently living in the 

househoId. In this report the data refer only to 

women who were currently married, widowed, 

divorced, or separated at the time of interview. 

The interview was focused on the respondents’ marital and pregnancy histories, their 

use of contraception and the planning status of 

each pregnancy, their intentions regarding number and spacing of future births, their maternal 

and family planning services, and on a broad 

range of social and economic characteristics. 

Between June 1973 and February 1974, 3,856 

1This report was prepared by Kathleen Ford, Ph.D., 

formerly with the Division of Vital Statistics. 

black women and 5,941 women of other races 

were interviewed for Cycle I of the National 

Survey of FamiIy Growth (NSFG). Between 

January and September of 1976, 3,009 bIack 

women and 5,602 women of other races were 

interviewed for Cycle H. 2 Further discussion of 

the survey design, definition of terms, and sampling vanability is in the Technical Notes. 

EXTENT OF IUD USE IN 

THE UNITED STATES 

Among married women in the United States, 

the use of the intrauterine device (IUD) increased from less than 1 percent in 1965 to 

about 6 percent during the 1970’s (table 1).3 As 

of 1976, simik.r percents (6.1) of both white 

and black married women were using the IUD. 

2The numbers of black and white women interviewed 

in Cycle II were revised for this report and differ slightly 

from those numbers reported in Advance Data, Nos. 36 

and 40. The revisions do not affect any other statistics 

reported here or previously. 

3Data for 1965 and 1970 are from the fiist and 

second National FertiIity Studies (NSF-I and NFS-11) 

and are reported, respectively, in Reproduction in the 

United States, 1965 by Ryder, N. B., and Westoff, C. F., 

Princeton, N.J. Princeton University Press, 1971; and in 

The Contraceptive Revolution, by Westoff, C. F., and 

Ryder, N.B., Princeton, N.J., Princeton University Press, 

1977. The figures in table 1 were computed from the 

computer tapes obtained from the Data and Program 

Library Service at the University of Wisconsin at 

Madison. 
19703

19703

---

2 dmcdata 

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

contraceptive method users who were using the IUD at the 

survey date, by marita I status and race: United States, 1965, 

1970,1973, and 1976 

Race and year 

All racesz 

1976 ........................... 

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

19703 ......................... 

19653 ......................... 

White 

1976 ....... ....................


a
 1973 ...........................


,9653 .........................


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

Black 

1976 ........................... 

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

,9653 ......................... 

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

lMethod use exclua 

Widowed, 

Currently married divorced 

and separated 

Percent Percent 

Percent of Percent of 

of method of method women usersl woman usersl 

6.1 12.5 9.1 20.0 

6.7 12.5 7.2 23.7 

5.0 9.3 *3.9 16.9 

* 0.7 *1.3 . . . 

6.1 12.4 9.4 19.4 

6.6 12.3 7.0 23.2 

4.9 8.9 *3.6 15.9 

*0.7 *1.2 -.. . . . 

6.1 13.4 8.8 22.3 

7.6 16.9 7.9 24.7 

5.0 11.1 5.3 22.2 

*1.5 *3.3 . . . .-. 

surgical :erilization in this table. 

card displaying pictures of IUD’s and were asked 

which type they had used most recently. About 

9 percent of the married women and 8 percent 

of the widowed, divorced, and sepaxated women 

did not know which type had been inserted. 

Table 2 shows the number and percent distribution of ever-married women whose current 

or most recent method of contraception was the 

IUD by type of IUD, according to race and marital status. Among married women, the Lippes 

Loop was the most popular method mentioned 

(37.7 percent of IUD users), followed by the 

Copper 7 (27.8 percent), the DaIkon ShieId 

(16.9 percent), and the Safe-T-Coil (12.5 percent ). The relative popularity of the different 

types of IUD’s among white and black women 

was similar except that more black women used 

the Safe-T-Coil than used either the Copper 7 or 

the Dalkon ShieId. Among widowed, divorced, 

or separated women, the Lippes Loop was also 

the most commonly used IUD, followed by 

the Copper 7, the Safe-T-Coil, and the Dalkon 

Shield. As may be seen in table 3 and figure I, 

the distribution of women who were currently 

using the IUD at the survey date, by type of 

IUD, is similar to that of women whose most 

recent method was the IUD (table 2). 

Figure 1. PERCENT DISTRIBUTION OF CURRENTLY MARRIED 

WOMEN 15-44 YEARS OF AGE USING THE IUD AT SURVEY 

DATE, BY TYPE OF IUD USED: UNITED STATES, 1976 

L ippes Copper Dalkon %fe. 

LooP ? Shield T.Coil Other 

a 

TYPE OF IUO USED 

z~lraces ticludes white, blac! and other races.


3Da*a for 1965 and 1970 are from the first and second


National Fertility Studies. 

Among widowed, divorced, and separated 

women the proportion was higher (about 9 percent) than among married women. 

Although the use of the IUD has increased in 

the last 10 years, it still represents a smalI part 

of American contraceptive practice. In 1976 the 

IUD was used by 12.5 percent of married users 

of nonsurgical contraceptive methods and by 

20.0 percent of those who were widowed, divorced, or separated. 

Type of IUD Used 

In the 1976 NSFG, women whose current or 

most recent method was the IUD were shown a 

Q. 
amcdata 3 

Table 2. Number of ever-married women 15-44 years of age whose most recent method of contraception was the IUD and percent distribution by type of IUD, according to marital status and race: United States, 1976 

I I 

Type of IUD used 

Number of . 

Marital status and race women in Lippes Safe-T- Copper Dal kon 

thousands Total LooP Coil 7 Shield Other 

Currently married I All racesl ...................................................... 1,990 100.0 37.7 I 12.51 27.8 ] 16.9 *5,0 

)== --4 I 

, I I 

White . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,802 100.0 II 36.1 I 12.41 29,21 17.8 I *4.5 

Black .................. .......................... .......... ............ ... 159 

Widowed, divorced, or separated I All racesl .. .... . . .. ... . ... .. .. ... .. . ... .. . .. ... .... . . ... . .. ... . 423 

l== 

White .... .. .. ... .. ... . .. ... ... . ... . .. ... .. . ... . .. ... . . ... .. .... ... ... . .. . 305 100.0 39.8 �1 7.3 27.4 *1O.9 *4.5 

Black ... ... .. .. .. .. .. .. ... . ... . .. ... .. ... .. .. . .. . .. ... .. .. .. .. . .. .. . ... . .. 112 100.0 I 62.3 *1 5.4 *1 5.0 *2.4 *4.7 

lNI ~ace~ includes white, black, and other races-. 

Parity of IUD Users 

using the various types of IUD’s differed by 

Among currently married women, IUD users pari;y or the number- ;f Iive births they have had 

are more likely to have had at least one child (table 4). For women with no live births, the 

@ (87.5 percent) compared with users of other nonsurgical contraceptive methods (79.0 percent). 

Copper 7 was the most popular type IUD, but 

for women w-M two or more children the 

The proportion of current$ married women Llppes Loop was the type most often used. 

Table 3. Nutier of ever-married women 15-44 years of age using the IUD at survey date and percent distribution by type of IUD, according to marital status and race: United States, 1976 

I I 

Type of IUD used 

Numbsr of 

Marital status and race women in Lippes Safe-T- Copper Dal kon 

thousands Total LooP Coil 7 Shield Other 

Currently married I I All racesl ............ .......................................... 1,582 100.0 35.2 13.1 30.2 15.3 ‘6.2 

White . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,436 100.0 33.7 13.1 31.5 15.9 *5.7 

Black .. .... . .. ... ... .. ... . .. .. .. .. .. .. ... . .. .. .. . ... . .. ... . .. .. .. .. .. . .. .. 124 100.0 51.3 * 15.8 * 14.8 �10.2 * 7.8 

Widowed, divorced, or separated 

All racesl .. . .. .. .. .. .. . .. ... .. . ... .. . ... . . ... . .. ... .. . ... . . ... . 311 100.0 48.5 * 15.8 24.6 *8.8 *2.2 

White ...................?. .......... ....................... .............. . 230 100.0 41.9 * 17.7 27.3 *11.6 �1.5 

Black ................. ................................................. ... 81 100.0 67.8 *10.3 *16.7 *0.9 *4.3 

1 Ml races includes white, black, and other races. 
4 ixkncedata 

Table 4. Number of currently married women 15-44 years of age using the IUD at survey date and percent distribution by type of IUD 

used, according to parity: United States, 1976 

I t 

Type of IUD used 

Number of 

Parity	 women in Lippes Safe-T- Copper Dalkon 

thousands Total LOOP Coil 7 Shield Other 

All .. ... ... .. . ... .... ... ... ... . ... .. . .... . . .. .. .. .. .... .. .. ... .. ... . 1,582 100.0 35.2 13.1 30.2 15.3 *6.2 

Zero ...... .. .. .... .. .. .. .. .. .. ... . .. .. .. .. .. .... . . .... .. .. .... . . ..... . ... . 205 100.0 *20.5 *2.6 50.6 *23.6 *2.8 

First ..... . ... .... ... . ..... . .. .... .. .. .... . .. ... .. .. .. .. ... .... .. . .... . . ... 351 100.0 24.8 * 12.3 36,3 *15.6 * 10.9 

Second or more .... .. . ... .. .. .. .. .. .. .... .. .. ... . .. . .... . . .... .. .. .. 1,026 100.0 42.3 16.8 23.4 13.3 *5.2 

TECHNICAL 

The Survey Design 

The National Survey of Family Growth 

(NSFG) is designed to provide data on fertility, 

family planning, and related aspects of maternal 

and child health. Field work for Cycle I was 

carried out by the National Opinion Research 

Center between June 1973 and February 1974. 

Field work for Cycle II was carried out by 

Westat, Inc., between Januzuy and September 

1976. 

A multistage probability sample of women 

in the household population of the conterminous United States was used in both cycles. 

Each time, approximately 33,000 households 

were screened to identify the sample of women 

who would be eligible for the NSFG, i.e., women aged 15 to 44 years, inclusive, who were 

currently married or previously married or who 

were never married but had offspring presently 

living in the household. In households with more 

than one eligible woman, a random procedure 

was used to select ordy one to be interviewed. 

Since the interviews were always conducted with 

the sample person, the term “respondent” is 

used as synonymous with sample person. A detailed description of the sample design for Cycle 

NOTES 

I is presented in “National Survey of Family 

Growth, Cycle I: Sample Design, Estimation 

Procedures, and Variance Estimation, ” Series 2, 

No. 76 in the Vital and Health Statistics series. 

A similar report is in preparation for CycIe 11. 

While the interviews varied greatly in the 

time required for their completion, they averaged about 70 minutes for Cycle I and about 58 

minutes for Cycle II. 

QuaIity control procedures were applied at 

all stages of the survey. These included a verification of Listing completeness, with unlisted 

dwelling units being brought into the sample; a 

preliminary field review of completed questionnaires for possible missing data or inaccurate administration; a 10-percent sample recheck of all 

households to be screened during the survey; observation of interviews in the field; and an independent recoding of a 5-percent subsample of 

compIeted interviews. 

Reliability of Estimates 

Since the statistics presented in this report 

are based on a sample, they may differ somewhat from the figures that would have been obtained if a complete census had been taken using 
.........................

ZKIWlncedata 5 

0 

the same questionnaires, instructions, inter- Table I L Approximate standard errors for estimated percentages 

expressed in percentage points for white and total women: viewing personnel, and field procedures. This 1973 National Survey of Family Growth. 

chance difference between sample results and a 

complete count is referred to as sampling error. I 

I 

Estimated rsercentaaa In addition, the results are also subject to non- Base of 

-, 

data processing mistakes, and nonresponse. It is T 98 95 80 80 70 60 

very difficult, if not impossible, to obtain 

accurate measures of nonsampling errors. These 100,000 ........... 3.0 4.6 6.4 8.5 9.7 10.4 10.6 

types of errors were kept to a minimum by the 500,000 .. ... ... .. 1.3 2.1 2.8 3.8 4.3 4.6 4.7 

1,000,000 ... . . ... 0.9 1.5 2.0 2.7 3.1 3.3 3.3 

sampling error due to respondent misreporting, percentage 2or 5or lOor 200r 30 or 40 or 50 

quality control procedures and by other 

3,000,000 ....._. 0.5 0.8 1-2 1.5 1.8 1.9 1.9 

methods incorporated into the survey design and 5,000,000 ........ 0.4 0.6 0.9 1.2 1.4 1.5 1.5 

administration. 7,000,000 ........ 0.3 0.5 T0.8 1.0 1.2 1.2 1.3

f 

1.0 1.1 Sampling error, or the extent to which sam- 10,000,000 ...... 0.3 0.5 0.6 0.8 1.0 

ples may differ by chance from a complete


count, is measured by a statistic called the stand- Table I I L Approximate standard errors for estimated numbers


ard error of estimate. Approximate standard for black woman: 1973 National Survey of Family Growth


errors for estimated numbers and percentages


from Cycle I are shown in tables I and II for the 8ize of Relative Standard


total and white populations and in tables III and estimate standard error error 

IV for the black population. Provisional esti­


mates for standard errors for Cycle II for total


and white women can be obtained by multi- 25,000 ............................ ..... 25.3 6,000


50,000 .................................. 17.9 9,000 plying the standard errors for these women from 100,000 ................................ 12.7 13,000 

Cycle I by a factor of 1.1. Similarly, provisional 150,000 ................................ 10.3 16,000 

estimates of standard errors for Cycle II for 250,000 ........................... ..... 8.0 20,000 

350,000 ........................... ..... 6.8 24,000 black women can be obtained by multiplying 500,000 ... ............ ................. 5.7 28,000 

the standard errors for these women from Cycle 750,000 ................................ 4.7 35,000 

I by a factor of 1.2. 1,000,000 ............................. 4.0 40,000 

Table IV. Approximate standard errors for estimated percentages 

Table 1. Approximate standard errors for estimated numbers for expressed in percentage points for black women: 1673 

white and total women: 1973 National 8urvey of Family Growth National Survey of Family Growth 

Relative Estimated percentage 

Size of standard Standard Base of 

estimate error error percentage 2or 5or 

50 98 95 

— 

50,000 .................................. 30.0 ‘i 5,000


100,000 ............ .................... 21.2 21,000 5,000 ............... 7.9 12.3 17.01 22.6 25.9 27.7 28.3


200,000 ................................ 15.0 30,000 10,000 ............. 5.6 8.7 12.0 16.0 18.3 19.6 20.0


500,000 ................................ 9.5 47,000 50,000 ............. 2.5 3.9 5.4 7.1 8.2 8.8 8.9


1,000,000 ............................. 6.7 67,000 100,000 ........... 1.8 2.7 3.8 5.1 5.8 6.2 6.3


2,000,000 .. ........................... 4.8 95,000 300,000 ........... 1.0 1.6 2.2 2.9 3.3 3.6 3.6


5,000,000 ............................. 3.0 151,000 500,000 ........... 0.8 1.2 1.7 2.3 2.6 2.8 2.8


10,000,000 . 2.2 216,000 .
 700,000 ........... 0.7 1.0 1.4 1.9 2.2 2.3 2.4

20,000,000 ........................... 1.5 311,000 1,000,000 ........ 0.6 0.9 1.2 1.6 1.8 2.0 2.0 

; I 1 1 I 
The chances are about 68 out of 100 that an 

estimate from the sample would differ from a 

complete census by less than the standard error. 

The chances are about 95 out of 100 that the 

differences between the sample estimate and a 

complete count would be less than twice the 

standard error. The relative standard error is the 

ratio of the standard error to the statistic being 

estimated. In this report, numbers and percentages which have a standard error that is 

more than 25 percent of the estimate itself are 

considered “unreliable.” They are marked with 

an asterisk to caution the user but may be combined to make other types of comparisons of 

greater precision. 

In this report, terms such as “similar” and 

“the same” mean that any observed difference 

between two estimatesbeing compared is not statistically si~ificant. Similarly, terms such as 

“greater,” “less,” “larger,” and “smaller” indicate that the observed differences are statistically significant. The normal deviate test with a 

0.5 level of significance was used to test all comparisons which are discussed in the text. A statistically significant difference is one large enough 

that in repeated samples of the same size and 

type as this one, such a large difference would 

be expected to be found in less than 5 percent 

of the samples. Lack of comment in the text 

between any two statistics does not mean the 

difference was tested and found not to be significant. 

Adjustment for nonsampling error due to 

nonresponse was made in two ways. Nonrespondent cases, as distinct from missing data 

items, were imputed by weighting for nonresponse within each primary sampling unit, 

stratum, and age-race category. In the 1973 survey, codes for missing items were imputed using 

a “hot deck” procedure. In the 1976 survey, 

imputation for missing data items has not been 

performed and the distributions shown in the 

tables are based only on those interviews where 

enough information was obtained from the respondent to determine contraceptive status. 

Cases for which the value of a given distribution is missingare shown in the totals. As a result, 

in the 1976 figures, about 1,061,000 women out 

of an estimated 31,847,000 total ever-married 

women are not represented in the distribution 

by contraceptive status. 

Definition of Terms 

Method U&mS.–A woman (or couple) who 

reported use of a contraceptive method at the 

date of interview was classified according to the , 

specific method used. 

Most Recent Method.–A woman (or couple) 

who reported use of a method at the time of 

interview was classified according to the specific 

method used. A woman (or couple) not using a 

method at the time of interview was classified 

according to the specific method used most 

recently. 

Type of Intrauterine Device .–Type of intrauterine device was determined by showing the 

woman being interviewed a card with pictures 

and names of IUD’s and asking her to identify 

the type she was using or had used. * 

Age.–In this report, age is classified by the 

age of the respondent at her last birthday before 

the date of interview. 

Race. –Classification by race, based on interviewer observation, was reported as black, white, 

or other. Race refers to the race of the woman 

interviewed. 

Man”tal status.–Persons are classified by marital status as married, widowed, divorced, separated, or never married. Married persons include those who report themselves as married or 

as informally mzmied, such as living with a 

partner or common-law spouse. Persons who are 

temporarily separated for reasons other than 

marital discord, such as vacation, illness, or 

Armed Forces, are classified as married. Divorced persons are those whose most recent marriage was legally dissolved and who are free to 

remarry. Women with an annulled marriage, 

while having the legal status of never having 

been married, axe classified together with the divorced. The category “separated” includes those 
---

who are Iegally or informally separated from However, in the NSFG, only single women with 

their most recent spouse due to marital discord. offspring living in the household are included 

The “never married” include those who have and separately classified.


never had a formal marriage and do not consider Parz-ty.–Parity refers to the number of live


themselves in any of the preceding categories. births the respondent has had. 

SYMBOLS 

Data not available 

I Category not applicable . . . I 

Quantity zero 

Quantity more.than O but less than 0.05— 0.0 

Figure does not meet standards of 

* reliability or precision 

Recent Issues of Advance Data From Vital and Health Statistics 

No. 42.	 Office Viiits to Cardiovascular Specialists, 

National Ambulatory itfedical Care Survey: 

United States, 1975-76 (Issued: October 31, 

1978) 

No. 41. Office Visits for Respiratory Conditions, 

National Ambulatory Medical Care Survey: 

United States, 1975-76 (Issued: October 30, 

1978) 

No. 40. Contraceptive Utilization Among Wzdowed, 

Dkorced, and Separated Women in the United 

States: 1973 and 1976 (Issued: September 22, 

1978) 

No. 39.	 Office Wits to Urologists, National Ambulatory Medical Care Survey: United States, 

1975-76 (Issued: September 7, 1978) 

No. 38.	 Office Viiits to Psychiatrists, National Ambulatory Me&al care Survey: United States, 

1975-76 (Issued: August 25, 1978) 

I A complete list of Advance Data From Vital and Health Statistics is available from the Scientific snd Technical 

Information Branch. I 

I I