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The fertility of young adolescents
JOURNAL OF ADOLESCENT HEALTH CARE 1:54-59, 1980
REVIEW ARTICLE
The Fertility of Young Adolescents WENDY BALDWIN, Ph.D.
This paper is a demographic analysis of trends and patterns in fertility behavior of adolescents under age 16 in the United States. Trends in numbers and rates of births are presented with particular attention to parity, race, and marital status. The sexual and contraceptive behavior of these women is discussed along with abortion behavior. KEY WORDS:
Abortion Adolescents Contraception Demography
Fertility Sex United States
For young adolescents--those under age 16--birth rates and numbers of births are low. However, the young adolescent may contribute more than her share of medical and social problems w h e n she engages in sexual intercourse, becomes pregnant, and either has an abortion or bears a child. A basic measure of fertility is the age-specific fertility rate, or the number of births per 1000 women of a given age. Because numbers of births are also a concern, it is important to look at the size of the young adolescent population, for the number of babies born to w o m e n under age 16 is a function of their birth rates and the numbers of such young women. This interrelationship is basic to an understanding of recent trends in adolescent childbearing. In 1977, the most recent year for which detailed statistics are available, the birth rates for 14- and 15-year-olds were 6.7 and 18.2, respectively. These rates are very low. By comparison, for women aged 20-24 the birth rate was 115.2 (National Center for From the Center for Population Research, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland. Direct reprint requests to: Wendy Baldwin, Ph.D., Center for Population Research, NICHD, NIH, Bethesda, MD 20205. Manuscript accepted February 20, 1980. 54 ISSN 0197-0070/80/010054-06/$02.25
Health Statistics, unpublished data). There were 42,411 births to women under age 16:30,956 to 15-year-olds and 11,455 to adolescents under age 15. Approximately four-fifths of births to women under 15 are to 14-year-olds. Young adolescents contributed 1.3% of all births in 1977 (1). To appreciate better the current figures, it is helpful to place them in historical perspective. Table 1 gives the birth rates for teenagers by single year of age from 1920 to the present and shows a trend similar to that among older women. Birth rates that had been falling before World War II rose from the mid-1940s to the late 1950s. This increase resulted from couples electing to have more children, couples having children as opposed to remaining childless, a "catching u p " of childbearing that was deferred because of the' war, and a trend toward marriage and childbearing at younger ages. It is not unusual for birth rates to rise after a war, but the boom observed in the United States was more extreme and protracted than that in most other countries or at other times in the United States. This increase applied to even young women, but when fertility rates began to fall, theirs fell more slowly. In fact, among young teens, birth rates rose slightly in the early 1970s. While the birth rates for even young adolescents are presently declining, it is only the older teenagers who have been able to push their fertility rates back to pre World War II levels. The post World War II baby boom has had an "echo" effect resulting from the large birth cohorts of the late 1940s and 1950s who are now young women able to bear children. Because of this increase in the population of adolescents, the number of births to women under age 20 has remained high, even though the overall birth rate for this age group has markedly decreased. For example, in 1960 there were 6780 births to adolescents under age 15, a number that peaked at 12,861 in 1973 and
(~ Society for Adolescent Medicine, 1980 Published by Elsevier North Holland, Inc., 52 Vanderbilt Ave., New York, NY 10017
September 1980
FERTILITY OF YOUNG ADOLESCENTS
55
Table 1. Births per 1000 W o m e n 14-19 Years of Age, by Single Years of Age, for All Women: United States, 1920-1977 Age (years) Period
14
15
16
17
18
19
1920-24 1925-29 1930-34 1935-39 1940-44
3.6 3.9 3.4 3.7 4.0
11.9 12.3 10.9 11.5 12.7
28.6 28.5 25.2 26.0 27.8
57.9 55.6 48.6 49.0 52.2
93.1 86.9 75.3 75.0 81.7
125.4 114.0 99.0 97.9 109.2
1945-49 1950-54 1955-59 1960-64
4.9 5.9 6.0 5.4
15.5 19.3 20.1 17.8
34.1 43.1 45.7 40.2
63.7 79.7 85.8 75.8
99.4 123.1 136.2 122.7
133.0 162.6 184.0 169.2
1965 1966 1967 1968 1969
5.2 5.3 5.3 5.7 6.0
16.5 16.4 16.5 16.7 17.4
36.0 35.5 35.3 35.2 35.8
66.4 64.8 63.2 62.6 63.1
105.4 101.8 97.5 95.7 95.7
142.4 136.1 129.5 125.2 124.5
1970 1971 1972 1973 1974
6.6 6.7 7.1 7.4 7.2
19.2 19.2 20.1 20.2 19.7
38.8 38.3 39.3 38.8 37.7
66.6 64.2 63.5 61.5 59.7
98.3 92.4 87.1 83.1 80.5
126.0 116.1 105.0 98.5 96.2
1975 1976 1977
7.1 6.8 6.7
19.4 18.6 18.2
36.4 34.6 34.5
57.3 54.2 54.2
77.5 73.3 73.8
92.7 88.7 89.5
10%
25%
37%
46%
51%
Percent decline from highest rate to 1977 9%
Sources: 1920-73: National Center for Health Statistics. Fertility Tables for Birth Cohorts by Color: United States, 1917-73. DHEW Publication No. (HRA) 76-1152, U.S. Government Printing Office, 1976, p 37 1974: National Center for Health Statistics. Vital Statistics of the United States: 1974. Volume 1--Natality. DHEW Publication No. (PHS) 78-1100, U.S. Government Printing Office, 1978, p 32 1975: National Center for Health Statistics. Vital Statistics of the United States: 1975. Volume 1--Natality. DHEW Publication No. (PHS) 78-1113, U.S. Government Printing Office, 1978, p 32 1976-1977: National Center for Health Statistics. Unpublished tabulations
n o w s t a n d s a t 11,485. S i n c e t h e adolescent population and birth g r o u p a r e n o w b o t h d e c l i n i n g , it in the coming years the numbers c o n t i n u e to d e c l i n e ( 2 - 4 ) .
s i z e of t h e y o u n g rates for that age appears likely that of such births will
Subgroup Differences S t a t i s t i c s for b i r t h s a r e a v a i l a b l e f o r w h i t e s , b l a c k s , and other races. Other nonwhites provide small n u m b e r s o f b i r t h s ( o n l y 788 to g i r l s a g e d 16 i n 1977). S i n c e t h e s e g r o u p s b e h a v e s o m e w h a t d i f f e r e n t l y , it is u s e f u l to l o o k a t t h e l e v e l a n d p a t t e r n of fertility separately. Birth rates for nonwhite adolesc e n t s ( 9 2 % o f w h o m a r e b l a c k ) (4,5) a r e s u b s t a n t i a l l y h i g h e r t h a n t h e r a t e s for w h i t e . T h e y o u n g e r the adolescent, the more discrepant are the rates, a s s h o w n i n T a b l e s 2 a n d 3. M o s t b i r t h s to a d o l e s c e n t s a r e first b i r t h s , b u t
the proportion varies somewhat with the mother's a g e a n d color. I n 1977, 9 5 % of t h e b i r t h s to a d o l e s c e n t s u n d e r a g e 15 w e r e first b i r t h s , w i t h a n a d d i tional 2.7% in which the birth order was not stated. For 15-year-olds, the proportion was 93%, with an u n s t a t e d 2 . 2 % . I n t e r m s of n u m b e r s of b i r t h s , w o m e n u n d e r 16 a c c o u n t e d for 39,508 first b i r t h s ; 1848, s e c o n d b i r t h s ; 74, t h i r d a n d f o u r t h b i r t h s ; a n d 1055, b i r t h s for w h i c h t h e o r d e r w a s n o t r e c o r d e d . G i v e n t h e h i g h e r b i r t h r a t e s for n o n w h i t e a d o l e s cents, one would expect differences in the distribut i o n o f b i r t h s b y p a r i t y a n d race. A m o n g w h i t e s , 9 5 % o f b i r t h s to a d o l e s c e n t s u n d e r a g e 16 a r e first b i r t h s , a n d a m o n g b l a c k s , 9 1 % a r e first b i r t h s . T h i s is n o t s u r p r i s i n g s i n c e a m a j o r c h a r a c t e r i s t i c of t h e b l a c k - w h i t e d i f f e r e n c e is t h a t b l a c k r a t e s a r e h i g h e r for y o u n g e r a g e s . T h i s m e a n s t h a t m o r e y o u n g b l a c k m o t h e r s a r e a b l e to h a v e a s e c o n d o r h i g h e r o r d e r b i r t h w h i l e still a n a d o l e s c e n t (4).
56
BALDWIN
JOURNAL OF ADOLESCENT HEALTH CARE Vol. 1, No. 1
Social costs accrue more immediately to outof-wedlock births and circumstances of such births are frequently characterized by limited resources for mother and child. Consequently, the marital status of teenagers who give birth is of interest. Where young adolescents are concerned, births are most frequently out of wedlock, with substantial differences between 15-year-otds and younger teens and between white and black adolescents. In 1977, 78% of the births to young adolescents were to single mothers; 88% for those under age 15 and 74% to those age 15. For both age groups combined, 69% of births to white adolescents were out of wedlock as opposed to 97% for blacks. Among other racial groups, 89% of the births were illegitimate. During the 1970s there has been a substantial increase in the likelihood that a birth will be out of wedlock, as can be seen by comparing 1977 data with 1970 data (Table 4). The biggest shift has been among whites, for w h o m the proportions were comparatively low in 1970 (1,4). The implications of an increase in illegitimate births are complex. Analysis of teenage (age 15-19) births shows that over time there has been a greater likelihood of a young woman having a premarital pregnancy as well as a decreased likelihood that a teenage couple will marry to legitimate a premarital conception (6). Analyses of the effect of an early birth on the mother and child indicate that both may have better outcomes in terms of mother's education and baby's health and well-being w h e n they have access to resources. For this age group the main resources may well come from the young mother's family. An insightful work by Frank Furstenberg addresses the adaptations families make to their young unmarried daughter's motherhood. While many families offer help in terms of food, lodging, and/or child care, they may also define the baby as
Table 3. Births per 1000 Women 14-15 Years of Age, by
Single Years of Age and Race: United States, 1970-1977 14-Year-olds
15-Year-olds
Year
White
Nonwhite
White
Nonwhite
1970 1971 1972 1973 1974 1975 1976 1977
3.6 3.7 4.1 4.3 4.3 4.4 4.2 4.1
23.8 23.6 24.1 24.5 22.8 22.1 20.5 20.0
12.6 12.4 13.2 13.6 13.5 13.4 12.8 12.6
58.0 57.6 58.2 57.0 53.6 51.2 48.6 47.4
Source: 1970-73: National Center for Health Statistics. Fertility Tables for Birth Cohorts by Color: United States, 1917-73. DHEW Publication No. (HRA) 76-1152, U.S. Government Printing Office, 1976, p 37
"theirs" as opposed to the young "mother's and father's." Considerably more research is needed on the influence of v e r y e a r l y parenthood on family structure and the effects of different living arrangements for the generations involved (7). To dichotomize births as "legitimate" or "illegitimate" is only taking a snapshot view of the circumstances at the time of the birth. Marriages begun when the partners are very young have higher rates of disruption, and young unmarried mothers have higher rates of marriage in the period following such a birth as well as higher rates of subsequent marital disruption. The considerable cross-over between these two groups makes discussion of the causes or implications of the legitimacy of a birth difficult (8).
Abortion Each year, a large number of legal abortions are performed on young adolescents. While the total number of legal abortions has risen yearly since the Table 4. Out-of-Wedlock Births to Young Adolescents
by Age and Race, 1970 and 1977 Table 2. Births per 1000 Women 14-19 Years of Age, by Single Years of Age and Race: United States, 1977 Age (years)
White
Nonwhite a
Ratio W/NW
14 15 16 17 18 19
4.1 12.6 26.4 44.1 63.0 79.3
20.0 47.4 77.0 107.4 131.3 145.3
1:4.9 1:3.8 1:2.9 1:2.4 1:2.1 1:1.8
Source: National Center for Health Statistics. Unpublished tabulations aWhile nonwhite rates are higher than white rates, nonwhite rates have shown a more consistent pattern of decline for young adolescents in the 1970s (see Table 3).
1970
1977
% Change 1970-77
PERCENTAGE OF OUT-OF-WEDLOCKBIRTHS Under 15 years of age, total 80.8 88.2 + 9.2 Nonwhite 94.2 98.8 ~ 4.6 White 57.9 72.8 + 25.7 15 years of age, total Nonwhite White
43.3 87.2 41.7
74.3 95.3 56.2
NUMBERS OF OUT-OF-WEDLOCK BIRTHS Under age 15 9500 10,100 15 19,300 23,000
+ 71.6 + 9.3 +34.8
+ 6.3 +19.2
September 1980
Supreme Court decision in 1973, the proportion of those abortions attributed to w o m e n under age 20 has remained about one-third. In 1977 there were an estimated 1.32 million abortions, 413,410 to teenagers (9). There are two major sources of abortion statistics. The Center for Disease Control (CDC) reports abortion surveillance data compiled from central state agencies and from hospitals or facilities in which abortions are performed (10). The Alan Guttmacher Institute (AGI) reports numbers of abortions based on survey of health institutions and private physicians providing abortion services. The AGI figure includes abortions performed in physicians' offices and is higher than the CDC figure. For this analysis, the overall figure from AGI is used with the age distribution estimated from the CDC material. Most reporting is in 5-year age groupings, but estimates for single years of age may be made from those states so reporting. Of those abortions reported in 1977 through the CDC abortion surveillance, 1.2% were to adolescents under age 15. This estimate is based on data from 37 states and leads to an estimated total number of abortions for w o m e n under age 15 of 15,690. F o r the 32 states reporting by single years of age, 11% of the abortions to w o m e n under 20 were to w o m e n under age 16, thus an estimated 45,500 abortions were to w o m e n under age 16 in 1977: 2900 to 13-year-olds, 12,800 to 14-year-olds, and 29,800 to 15-year-olds (10). This means that the 15-year-old is about equally likely to end a pregnancy in a live birth as in a legal abortion, but a younger adolescent is more likely to resolve a pregnancy in abortion. Little can be said about abortion trends over time, because legal abortion has such a short history, and virtually no national statistics exist for abortion before 1973. In the period from 1973 to 1977, the estimated number of legal abortions obtained by adolescents under age 15 rose from 11,550 in 1973 to 13,630 in 1974; to 15,520 in 1975; to 15,820 in 1976; and to 15,690 in 1977 (9). This suggests a rising abortion ratio for this age group, i.e., a growing likelihood that a pregnancy will be terminated in a legal abortion.
Sex and Contraception The likelihood that an adolescent will be sexually active has been increasing, and although contraceptive practice is improving, there are still major gaps in protection. Two national probability surveys of women age 15-19 conducted at Johns Hopkins University by Drs. Kantner and Zelnik point to an
FERTILITYOF YOUNG ADOLESCENTS
57
increase in sexual activity among the unmarried over the period 1971-1976. In the 1971 survey, 13.8% of 15-year-olds reported that they were sexually active, a proportion that rose by 30% to 18.0% in 1976. For sexually active 15-year-olds, the median age at first intercourse was 14.7 in both periods. The likelihood that a black adolescent aged 15 will be sexually active is higher (38.4%) than for a white teen (13.8%), but the rate of increase in sexual activity among 15-year-olds was similar for blacks and whites. At older ages whites had much greater increases during this period, as shown in Table 5. The median age at first intercourse for all sexually active 15-19-year-olds was 16.2 in 1976 (11). Consequently, almost half of those who will become sexually active while an unmarried teen will first have intercourse as a young adolescent. The phrase "sexually active" must be used with some caution. In this, and in most writings, it refers to those who have had sexual intercourse at least once. In fact, m a n y teens are not very active sexually, as the Kantner and Zelnik data show. Of "nonvirgin" 15-17-year-olds, approximately 1 in 5 report having had sex only once. When frequency of intercourse was measured, 51% of sexually experienced 15-17-year-olds had not had sex in the 4 weeks preceding the survey and another 30% had had sex only once or twice during that period. In 1976 more than half of the 15-17-year-olds had had only one partner (14.5% reported four or more partners). When this is compared with 1971 data, it appears that recently, fewer teens had confined themselves to one partner and that more had had several partners. Of course, any trend toward earlier first intercourse means there is more time available to switch partners. The authors of this study note "the decline in age at first intercourse for 15-19-year-olds from 16.5 to 16.2 years" (11). This decline occurs at virtually each age, which is consistent w i t h the apparent general relaxation in sexual behavior that has been observed. There has been both an increase in the proportion of teens who have had intercourse and a relative increase in the number of partners (11). Table 5. Percent Unmarried Women Experiencing Sexual Intercourse, 1971 and 1976 (11) Age (years)
1971
1976
Percent increase
15-19 15 16 17 18 19
26.8 13.8 21.2 26.6 36.8 46.8
36.9 18.0 25.4 40.9 45.2 55.2
30.2 30.4 19.8 53.8 22.8 17.9
58
BALDWIN
JOURNAL OF ADOLESCENT HEALTH CARE Vol. 1, No. 1
The data from these surveys s h o w a mixed t r e n d in contraceptive practice. A m o n g 15-year-olds, the p r o p o r t i o n n e v e r contraceptively p r o t e c t e d rose from 32.9% to 38.0% d u r i n g this five-year period, b u t the p r o p o r t i o n always protected or p r o t e c t e d at last intercourse also rose. In the case of those adolescents always protected, the p r o p o r t i o n rose f r o m 19.7% to 2 9 . 5 % - - a n increase of 50%. W h e n the m o s t recent act of intercourse is considered, the change is a spectacular 80% i m p r o v e m e n t from 29.9% to 53.8% always protected. This change was m o s t a p p a r e n t a m o n g whites. Both blacks a n d whites s h o w e d a similar pattern of change over the period, with pill use increasing at the expense of the c o n d o m a n d withdrawal. W h e n all m e t h o d s ever u s e d are considered, there was a considerable d r o p in the use of d o u c h e a n d an increase in the use of r h y t h m . Analysis of the m e t h o d u s e d m o s t recently gives a clearer picture of contraceptive practice. Table 6 shows the p r o p o r t i o n of sexually active 15-17-year-olds using each m e t h o d and the p e r c e n t change in use from 1971 to 1976 (11). The y o u n g e r the adolescent at the time of first intercourse, the less likely she is to be contraceptively protected. K a n t n e r a n d Zelnik f o u n d n o evidence that the gap b e t w e e n first intercourse and first contraceptive use is lessening. The y o u n g e r the adolescent at first intercourse, the greater the gap. A recent analysis b y Zabin et al. of the risk of p r e g n a n c y d u r i n g the first m o n t h s of exposure s h o w s that for w o m e n w h o were 18 or 19 at the time of the 1976 survey, " n e a r l y one-fifth b e c a m e p r e g n a n t six m o n t h s after first b e g i n n i n g sexual i n t e r c o u r s e " (12). Of all the first pregnancies these girls experienced, half occurred in that first sixm o n t h period a n d m o r e t h a n one-fifth of that n u m b e r in the first m o n t h . The risk of p r e g n a n c y occurring d u r i n g this initial period is twice as great for girls w h o first have intercourse at age 15 or
Table 6, Use of Method of Contraception at Last Intercourse, Women Age 15-17 by Race, 1976 (11) Method Pill IUD Condom Douche Withdrawal Other
All
White
Black
36.4 (+136)~ 2.4 (+300) 27.6 (-32) 3.8 (-42) 24.7 (-22) 5.1 (--)
35.5 (+203) 3.5 (~) 27.7 (-27) 2.8 (-17) 25.5 (-39) 5.0 (-12)
52.8 (+142) 2.7 (--) 25.3 (-41) 6.9 (-50) 8.2 (-46) 4.1 (+28)
aThe percent change over the period 1971-1976 is shown in parentheses. b0.0 in 1971.
y o u n g e r t h a n for those w h o wait until t h e y are 18 or 19. Despite some a p p a r e n t s u b f e c u n d i t y a m o n g y o u n g adolescents, their p o o r use of contraceptives puts t h e m at v e r y high risk for conception. For all w o m e n w h o begin sex at age 15 or y o u n g e r , over 9 % b e c o m e p r e g n a n t in the first m o n t h of e x p o s u r e - - 7 . 6 % for whites a n d 15.3% for blacks. After 6 m o n t h s , the p r o p o r t i o n w h o b e c o m e pregn a n t rises overall to 2 0 . 7 - - 1 9 . 7 % for whites a n d 28.2% for blacks (12).
Conclusions Childbearing is not a n e w p h e n o m e n o n for teenagers, b u t the likelihood of entering into r e p r o d u c t i v e b e h a v i o r as a y o u n g adolescent w o m a n has apparently increased. Adolescents u n d e r age 16 t o d a y are m o r e likely to bear a child t h a n their counterparts a generation a g o - - d e s p i t e the fact that birth rates a m o n g older w o m e n h a v e declined in this period. Increasingly, the adolescent is e x p o s e d to sexual activity while quite y o u n g a n d her relatively p o o r record regarding contraceptive protection places her at the highest risk of b e c o m i n g pregnant. This risk is particulary high d u r i n g the first m o n t h s of sexual intercourse. P r o g r a m s that dep e n d on adolescents to come for s e r v i c e s - educational or c o n t r a c e p t i v e - - a f t e r t h e y initiate sexual intercourse will probably miss m a n y adolescents. Adolescents t e n d to delay seeking help, a n d m a n y thus experience u n w a n t e d pregnancies.
References 1. National Center for Health Statistics: Monthly Vital Statistics Report: Final Natality Statistics, 1970. Rockville, Md., National Center for Health Statistics, 1974. (Vol. 22, No. 12, Suppl., March 20) (DHEW publication No. (HRA) 74-1120) 2. National Center for Health Statistics: Vital Statistics. Vital Statistics of the United States. Volume 1: Natality 19501960. Rockville, Md., National Center for Health Statistics 3. National Center for Health Statistics: Monthly Vital Statistics Report: Final Natality Statistics, 1973. Rockville, Md.: National Center for Health Statistics, 1975. (Vol. 23, No. 11, Suppl., January 30) (DHEW publication No. (HRA) 75-1120) 4. National Center for Health Statistics: Monthly Vital Statistics Report: Final Natality Statistics, 1977. Rockville, Md., National Center for Health Statistics, 1979. (Vol. 27, No. 11, Suppl., February 5) (DHEW publication No. (HRA) 79-1120) 5. Baldwin WH: Adolescent pregnancy and childbearing-Growing concerns for Americans. Population Bulletin 31: 2; 1980 update. Washington, D.C., Population Reference Bureau, Inc. 6. O'Connell M, Moore MJ: The legitimacy status of first births: A retrospective study, 1939-42 to 1975-78. Family Plann Perspect 12:1, 1980
September 1980
7. Baldwin W, Cain VS: The children of teenage parents. Family Plann Perspect 12:34-43, 1980 8. Moore KA, Waite LJ, Hofferth SL, Caldwell SB: The consequences of age at first childbirth: Marriage, separation and divorce. Final report to NICHD. Springfield, Va., National Technical Information Service Report No. PB 289053/AS, 1978 9. Forrest JD, Sullivan E, Tietze C: Abortion in the United States, 1977-1978. Family Plann Perspect 11:329-341, 1979
FERTILITY OF YOUNG ADOLESCENTS
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10. Center for Disease Control: AbQrtion Surveillance, 1977. Atlanta, Ga., Center for Disease Control, September 1979 11. Zelnik M, Kantner JF: Sexual and contraceptive experience of young unmarried women. Family Plann Perspect 9:55-71, 1977 12. Zabin LS, Kantner JF, Zelnik M: The risk of adolescent pregnancy in the first months of intercourse. Family Plann Perspect 11:215-222, 1979
REVIEW ARTICLE
The Fertility of Young Adolescents WENDY BALDWIN, Ph.D.
This paper is a demographic analysis of trends and patterns in fertility behavior of adolescents under age 16 in the United States. Trends in numbers and rates of births are presented with particular attention to parity, race, and marital status. The sexual and contraceptive behavior of these women is discussed along with abortion behavior. KEY WORDS:
Abortion Adolescents Contraception Demography
Fertility Sex United States
For young adolescents--those under age 16--birth rates and numbers of births are low. However, the young adolescent may contribute more than her share of medical and social problems w h e n she engages in sexual intercourse, becomes pregnant, and either has an abortion or bears a child. A basic measure of fertility is the age-specific fertility rate, or the number of births per 1000 women of a given age. Because numbers of births are also a concern, it is important to look at the size of the young adolescent population, for the number of babies born to w o m e n under age 16 is a function of their birth rates and the numbers of such young women. This interrelationship is basic to an understanding of recent trends in adolescent childbearing. In 1977, the most recent year for which detailed statistics are available, the birth rates for 14- and 15-year-olds were 6.7 and 18.2, respectively. These rates are very low. By comparison, for women aged 20-24 the birth rate was 115.2 (National Center for From the Center for Population Research, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland. Direct reprint requests to: Wendy Baldwin, Ph.D., Center for Population Research, NICHD, NIH, Bethesda, MD 20205. Manuscript accepted February 20, 1980. 54 ISSN 0197-0070/80/010054-06/$02.25
Health Statistics, unpublished data). There were 42,411 births to women under age 16:30,956 to 15-year-olds and 11,455 to adolescents under age 15. Approximately four-fifths of births to women under 15 are to 14-year-olds. Young adolescents contributed 1.3% of all births in 1977 (1). To appreciate better the current figures, it is helpful to place them in historical perspective. Table 1 gives the birth rates for teenagers by single year of age from 1920 to the present and shows a trend similar to that among older women. Birth rates that had been falling before World War II rose from the mid-1940s to the late 1950s. This increase resulted from couples electing to have more children, couples having children as opposed to remaining childless, a "catching u p " of childbearing that was deferred because of the' war, and a trend toward marriage and childbearing at younger ages. It is not unusual for birth rates to rise after a war, but the boom observed in the United States was more extreme and protracted than that in most other countries or at other times in the United States. This increase applied to even young women, but when fertility rates began to fall, theirs fell more slowly. In fact, among young teens, birth rates rose slightly in the early 1970s. While the birth rates for even young adolescents are presently declining, it is only the older teenagers who have been able to push their fertility rates back to pre World War II levels. The post World War II baby boom has had an "echo" effect resulting from the large birth cohorts of the late 1940s and 1950s who are now young women able to bear children. Because of this increase in the population of adolescents, the number of births to women under age 20 has remained high, even though the overall birth rate for this age group has markedly decreased. For example, in 1960 there were 6780 births to adolescents under age 15, a number that peaked at 12,861 in 1973 and
(~ Society for Adolescent Medicine, 1980 Published by Elsevier North Holland, Inc., 52 Vanderbilt Ave., New York, NY 10017
September 1980
FERTILITY OF YOUNG ADOLESCENTS
55
Table 1. Births per 1000 W o m e n 14-19 Years of Age, by Single Years of Age, for All Women: United States, 1920-1977 Age (years) Period
14
15
16
17
18
19
1920-24 1925-29 1930-34 1935-39 1940-44
3.6 3.9 3.4 3.7 4.0
11.9 12.3 10.9 11.5 12.7
28.6 28.5 25.2 26.0 27.8
57.9 55.6 48.6 49.0 52.2
93.1 86.9 75.3 75.0 81.7
125.4 114.0 99.0 97.9 109.2
1945-49 1950-54 1955-59 1960-64
4.9 5.9 6.0 5.4
15.5 19.3 20.1 17.8
34.1 43.1 45.7 40.2
63.7 79.7 85.8 75.8
99.4 123.1 136.2 122.7
133.0 162.6 184.0 169.2
1965 1966 1967 1968 1969
5.2 5.3 5.3 5.7 6.0
16.5 16.4 16.5 16.7 17.4
36.0 35.5 35.3 35.2 35.8
66.4 64.8 63.2 62.6 63.1
105.4 101.8 97.5 95.7 95.7
142.4 136.1 129.5 125.2 124.5
1970 1971 1972 1973 1974
6.6 6.7 7.1 7.4 7.2
19.2 19.2 20.1 20.2 19.7
38.8 38.3 39.3 38.8 37.7
66.6 64.2 63.5 61.5 59.7
98.3 92.4 87.1 83.1 80.5
126.0 116.1 105.0 98.5 96.2
1975 1976 1977
7.1 6.8 6.7
19.4 18.6 18.2
36.4 34.6 34.5
57.3 54.2 54.2
77.5 73.3 73.8
92.7 88.7 89.5
10%
25%
37%
46%
51%
Percent decline from highest rate to 1977 9%
Sources: 1920-73: National Center for Health Statistics. Fertility Tables for Birth Cohorts by Color: United States, 1917-73. DHEW Publication No. (HRA) 76-1152, U.S. Government Printing Office, 1976, p 37 1974: National Center for Health Statistics. Vital Statistics of the United States: 1974. Volume 1--Natality. DHEW Publication No. (PHS) 78-1100, U.S. Government Printing Office, 1978, p 32 1975: National Center for Health Statistics. Vital Statistics of the United States: 1975. Volume 1--Natality. DHEW Publication No. (PHS) 78-1113, U.S. Government Printing Office, 1978, p 32 1976-1977: National Center for Health Statistics. Unpublished tabulations
n o w s t a n d s a t 11,485. S i n c e t h e adolescent population and birth g r o u p a r e n o w b o t h d e c l i n i n g , it in the coming years the numbers c o n t i n u e to d e c l i n e ( 2 - 4 ) .
s i z e of t h e y o u n g rates for that age appears likely that of such births will
Subgroup Differences S t a t i s t i c s for b i r t h s a r e a v a i l a b l e f o r w h i t e s , b l a c k s , and other races. Other nonwhites provide small n u m b e r s o f b i r t h s ( o n l y 788 to g i r l s a g e d 16 i n 1977). S i n c e t h e s e g r o u p s b e h a v e s o m e w h a t d i f f e r e n t l y , it is u s e f u l to l o o k a t t h e l e v e l a n d p a t t e r n of fertility separately. Birth rates for nonwhite adolesc e n t s ( 9 2 % o f w h o m a r e b l a c k ) (4,5) a r e s u b s t a n t i a l l y h i g h e r t h a n t h e r a t e s for w h i t e . T h e y o u n g e r the adolescent, the more discrepant are the rates, a s s h o w n i n T a b l e s 2 a n d 3. M o s t b i r t h s to a d o l e s c e n t s a r e first b i r t h s , b u t
the proportion varies somewhat with the mother's a g e a n d color. I n 1977, 9 5 % of t h e b i r t h s to a d o l e s c e n t s u n d e r a g e 15 w e r e first b i r t h s , w i t h a n a d d i tional 2.7% in which the birth order was not stated. For 15-year-olds, the proportion was 93%, with an u n s t a t e d 2 . 2 % . I n t e r m s of n u m b e r s of b i r t h s , w o m e n u n d e r 16 a c c o u n t e d for 39,508 first b i r t h s ; 1848, s e c o n d b i r t h s ; 74, t h i r d a n d f o u r t h b i r t h s ; a n d 1055, b i r t h s for w h i c h t h e o r d e r w a s n o t r e c o r d e d . G i v e n t h e h i g h e r b i r t h r a t e s for n o n w h i t e a d o l e s cents, one would expect differences in the distribut i o n o f b i r t h s b y p a r i t y a n d race. A m o n g w h i t e s , 9 5 % o f b i r t h s to a d o l e s c e n t s u n d e r a g e 16 a r e first b i r t h s , a n d a m o n g b l a c k s , 9 1 % a r e first b i r t h s . T h i s is n o t s u r p r i s i n g s i n c e a m a j o r c h a r a c t e r i s t i c of t h e b l a c k - w h i t e d i f f e r e n c e is t h a t b l a c k r a t e s a r e h i g h e r for y o u n g e r a g e s . T h i s m e a n s t h a t m o r e y o u n g b l a c k m o t h e r s a r e a b l e to h a v e a s e c o n d o r h i g h e r o r d e r b i r t h w h i l e still a n a d o l e s c e n t (4).
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JOURNAL OF ADOLESCENT HEALTH CARE Vol. 1, No. 1
Social costs accrue more immediately to outof-wedlock births and circumstances of such births are frequently characterized by limited resources for mother and child. Consequently, the marital status of teenagers who give birth is of interest. Where young adolescents are concerned, births are most frequently out of wedlock, with substantial differences between 15-year-otds and younger teens and between white and black adolescents. In 1977, 78% of the births to young adolescents were to single mothers; 88% for those under age 15 and 74% to those age 15. For both age groups combined, 69% of births to white adolescents were out of wedlock as opposed to 97% for blacks. Among other racial groups, 89% of the births were illegitimate. During the 1970s there has been a substantial increase in the likelihood that a birth will be out of wedlock, as can be seen by comparing 1977 data with 1970 data (Table 4). The biggest shift has been among whites, for w h o m the proportions were comparatively low in 1970 (1,4). The implications of an increase in illegitimate births are complex. Analysis of teenage (age 15-19) births shows that over time there has been a greater likelihood of a young woman having a premarital pregnancy as well as a decreased likelihood that a teenage couple will marry to legitimate a premarital conception (6). Analyses of the effect of an early birth on the mother and child indicate that both may have better outcomes in terms of mother's education and baby's health and well-being w h e n they have access to resources. For this age group the main resources may well come from the young mother's family. An insightful work by Frank Furstenberg addresses the adaptations families make to their young unmarried daughter's motherhood. While many families offer help in terms of food, lodging, and/or child care, they may also define the baby as
Table 3. Births per 1000 Women 14-15 Years of Age, by
Single Years of Age and Race: United States, 1970-1977 14-Year-olds
15-Year-olds
Year
White
Nonwhite
White
Nonwhite
1970 1971 1972 1973 1974 1975 1976 1977
3.6 3.7 4.1 4.3 4.3 4.4 4.2 4.1
23.8 23.6 24.1 24.5 22.8 22.1 20.5 20.0
12.6 12.4 13.2 13.6 13.5 13.4 12.8 12.6
58.0 57.6 58.2 57.0 53.6 51.2 48.6 47.4
Source: 1970-73: National Center for Health Statistics. Fertility Tables for Birth Cohorts by Color: United States, 1917-73. DHEW Publication No. (HRA) 76-1152, U.S. Government Printing Office, 1976, p 37
"theirs" as opposed to the young "mother's and father's." Considerably more research is needed on the influence of v e r y e a r l y parenthood on family structure and the effects of different living arrangements for the generations involved (7). To dichotomize births as "legitimate" or "illegitimate" is only taking a snapshot view of the circumstances at the time of the birth. Marriages begun when the partners are very young have higher rates of disruption, and young unmarried mothers have higher rates of marriage in the period following such a birth as well as higher rates of subsequent marital disruption. The considerable cross-over between these two groups makes discussion of the causes or implications of the legitimacy of a birth difficult (8).
Abortion Each year, a large number of legal abortions are performed on young adolescents. While the total number of legal abortions has risen yearly since the Table 4. Out-of-Wedlock Births to Young Adolescents
by Age and Race, 1970 and 1977 Table 2. Births per 1000 Women 14-19 Years of Age, by Single Years of Age and Race: United States, 1977 Age (years)
White
Nonwhite a
Ratio W/NW
14 15 16 17 18 19
4.1 12.6 26.4 44.1 63.0 79.3
20.0 47.4 77.0 107.4 131.3 145.3
1:4.9 1:3.8 1:2.9 1:2.4 1:2.1 1:1.8
Source: National Center for Health Statistics. Unpublished tabulations aWhile nonwhite rates are higher than white rates, nonwhite rates have shown a more consistent pattern of decline for young adolescents in the 1970s (see Table 3).
1970
1977
% Change 1970-77
PERCENTAGE OF OUT-OF-WEDLOCKBIRTHS Under 15 years of age, total 80.8 88.2 + 9.2 Nonwhite 94.2 98.8 ~ 4.6 White 57.9 72.8 + 25.7 15 years of age, total Nonwhite White
43.3 87.2 41.7
74.3 95.3 56.2
NUMBERS OF OUT-OF-WEDLOCK BIRTHS Under age 15 9500 10,100 15 19,300 23,000
+ 71.6 + 9.3 +34.8
+ 6.3 +19.2
September 1980
Supreme Court decision in 1973, the proportion of those abortions attributed to w o m e n under age 20 has remained about one-third. In 1977 there were an estimated 1.32 million abortions, 413,410 to teenagers (9). There are two major sources of abortion statistics. The Center for Disease Control (CDC) reports abortion surveillance data compiled from central state agencies and from hospitals or facilities in which abortions are performed (10). The Alan Guttmacher Institute (AGI) reports numbers of abortions based on survey of health institutions and private physicians providing abortion services. The AGI figure includes abortions performed in physicians' offices and is higher than the CDC figure. For this analysis, the overall figure from AGI is used with the age distribution estimated from the CDC material. Most reporting is in 5-year age groupings, but estimates for single years of age may be made from those states so reporting. Of those abortions reported in 1977 through the CDC abortion surveillance, 1.2% were to adolescents under age 15. This estimate is based on data from 37 states and leads to an estimated total number of abortions for w o m e n under age 15 of 15,690. F o r the 32 states reporting by single years of age, 11% of the abortions to w o m e n under 20 were to w o m e n under age 16, thus an estimated 45,500 abortions were to w o m e n under age 16 in 1977: 2900 to 13-year-olds, 12,800 to 14-year-olds, and 29,800 to 15-year-olds (10). This means that the 15-year-old is about equally likely to end a pregnancy in a live birth as in a legal abortion, but a younger adolescent is more likely to resolve a pregnancy in abortion. Little can be said about abortion trends over time, because legal abortion has such a short history, and virtually no national statistics exist for abortion before 1973. In the period from 1973 to 1977, the estimated number of legal abortions obtained by adolescents under age 15 rose from 11,550 in 1973 to 13,630 in 1974; to 15,520 in 1975; to 15,820 in 1976; and to 15,690 in 1977 (9). This suggests a rising abortion ratio for this age group, i.e., a growing likelihood that a pregnancy will be terminated in a legal abortion.
Sex and Contraception The likelihood that an adolescent will be sexually active has been increasing, and although contraceptive practice is improving, there are still major gaps in protection. Two national probability surveys of women age 15-19 conducted at Johns Hopkins University by Drs. Kantner and Zelnik point to an
FERTILITYOF YOUNG ADOLESCENTS
57
increase in sexual activity among the unmarried over the period 1971-1976. In the 1971 survey, 13.8% of 15-year-olds reported that they were sexually active, a proportion that rose by 30% to 18.0% in 1976. For sexually active 15-year-olds, the median age at first intercourse was 14.7 in both periods. The likelihood that a black adolescent aged 15 will be sexually active is higher (38.4%) than for a white teen (13.8%), but the rate of increase in sexual activity among 15-year-olds was similar for blacks and whites. At older ages whites had much greater increases during this period, as shown in Table 5. The median age at first intercourse for all sexually active 15-19-year-olds was 16.2 in 1976 (11). Consequently, almost half of those who will become sexually active while an unmarried teen will first have intercourse as a young adolescent. The phrase "sexually active" must be used with some caution. In this, and in most writings, it refers to those who have had sexual intercourse at least once. In fact, m a n y teens are not very active sexually, as the Kantner and Zelnik data show. Of "nonvirgin" 15-17-year-olds, approximately 1 in 5 report having had sex only once. When frequency of intercourse was measured, 51% of sexually experienced 15-17-year-olds had not had sex in the 4 weeks preceding the survey and another 30% had had sex only once or twice during that period. In 1976 more than half of the 15-17-year-olds had had only one partner (14.5% reported four or more partners). When this is compared with 1971 data, it appears that recently, fewer teens had confined themselves to one partner and that more had had several partners. Of course, any trend toward earlier first intercourse means there is more time available to switch partners. The authors of this study note "the decline in age at first intercourse for 15-19-year-olds from 16.5 to 16.2 years" (11). This decline occurs at virtually each age, which is consistent w i t h the apparent general relaxation in sexual behavior that has been observed. There has been both an increase in the proportion of teens who have had intercourse and a relative increase in the number of partners (11). Table 5. Percent Unmarried Women Experiencing Sexual Intercourse, 1971 and 1976 (11) Age (years)
1971
1976
Percent increase
15-19 15 16 17 18 19
26.8 13.8 21.2 26.6 36.8 46.8
36.9 18.0 25.4 40.9 45.2 55.2
30.2 30.4 19.8 53.8 22.8 17.9
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BALDWIN
JOURNAL OF ADOLESCENT HEALTH CARE Vol. 1, No. 1
The data from these surveys s h o w a mixed t r e n d in contraceptive practice. A m o n g 15-year-olds, the p r o p o r t i o n n e v e r contraceptively p r o t e c t e d rose from 32.9% to 38.0% d u r i n g this five-year period, b u t the p r o p o r t i o n always protected or p r o t e c t e d at last intercourse also rose. In the case of those adolescents always protected, the p r o p o r t i o n rose f r o m 19.7% to 2 9 . 5 % - - a n increase of 50%. W h e n the m o s t recent act of intercourse is considered, the change is a spectacular 80% i m p r o v e m e n t from 29.9% to 53.8% always protected. This change was m o s t a p p a r e n t a m o n g whites. Both blacks a n d whites s h o w e d a similar pattern of change over the period, with pill use increasing at the expense of the c o n d o m a n d withdrawal. W h e n all m e t h o d s ever u s e d are considered, there was a considerable d r o p in the use of d o u c h e a n d an increase in the use of r h y t h m . Analysis of the m e t h o d u s e d m o s t recently gives a clearer picture of contraceptive practice. Table 6 shows the p r o p o r t i o n of sexually active 15-17-year-olds using each m e t h o d and the p e r c e n t change in use from 1971 to 1976 (11). The y o u n g e r the adolescent at the time of first intercourse, the less likely she is to be contraceptively protected. K a n t n e r a n d Zelnik f o u n d n o evidence that the gap b e t w e e n first intercourse and first contraceptive use is lessening. The y o u n g e r the adolescent at first intercourse, the greater the gap. A recent analysis b y Zabin et al. of the risk of p r e g n a n c y d u r i n g the first m o n t h s of exposure s h o w s that for w o m e n w h o were 18 or 19 at the time of the 1976 survey, " n e a r l y one-fifth b e c a m e p r e g n a n t six m o n t h s after first b e g i n n i n g sexual i n t e r c o u r s e " (12). Of all the first pregnancies these girls experienced, half occurred in that first sixm o n t h period a n d m o r e t h a n one-fifth of that n u m b e r in the first m o n t h . The risk of p r e g n a n c y occurring d u r i n g this initial period is twice as great for girls w h o first have intercourse at age 15 or
Table 6, Use of Method of Contraception at Last Intercourse, Women Age 15-17 by Race, 1976 (11) Method Pill IUD Condom Douche Withdrawal Other
All
White
Black
36.4 (+136)~ 2.4 (+300) 27.6 (-32) 3.8 (-42) 24.7 (-22) 5.1 (--)
35.5 (+203) 3.5 (~) 27.7 (-27) 2.8 (-17) 25.5 (-39) 5.0 (-12)
52.8 (+142) 2.7 (--) 25.3 (-41) 6.9 (-50) 8.2 (-46) 4.1 (+28)
aThe percent change over the period 1971-1976 is shown in parentheses. b0.0 in 1971.
y o u n g e r t h a n for those w h o wait until t h e y are 18 or 19. Despite some a p p a r e n t s u b f e c u n d i t y a m o n g y o u n g adolescents, their p o o r use of contraceptives puts t h e m at v e r y high risk for conception. For all w o m e n w h o begin sex at age 15 or y o u n g e r , over 9 % b e c o m e p r e g n a n t in the first m o n t h of e x p o s u r e - - 7 . 6 % for whites a n d 15.3% for blacks. After 6 m o n t h s , the p r o p o r t i o n w h o b e c o m e pregn a n t rises overall to 2 0 . 7 - - 1 9 . 7 % for whites a n d 28.2% for blacks (12).
Conclusions Childbearing is not a n e w p h e n o m e n o n for teenagers, b u t the likelihood of entering into r e p r o d u c t i v e b e h a v i o r as a y o u n g adolescent w o m a n has apparently increased. Adolescents u n d e r age 16 t o d a y are m o r e likely to bear a child t h a n their counterparts a generation a g o - - d e s p i t e the fact that birth rates a m o n g older w o m e n h a v e declined in this period. Increasingly, the adolescent is e x p o s e d to sexual activity while quite y o u n g a n d her relatively p o o r record regarding contraceptive protection places her at the highest risk of b e c o m i n g pregnant. This risk is particulary high d u r i n g the first m o n t h s of sexual intercourse. P r o g r a m s that dep e n d on adolescents to come for s e r v i c e s - educational or c o n t r a c e p t i v e - - a f t e r t h e y initiate sexual intercourse will probably miss m a n y adolescents. Adolescents t e n d to delay seeking help, a n d m a n y thus experience u n w a n t e d pregnancies.
References 1. National Center for Health Statistics: Monthly Vital Statistics Report: Final Natality Statistics, 1970. Rockville, Md., National Center for Health Statistics, 1974. (Vol. 22, No. 12, Suppl., March 20) (DHEW publication No. (HRA) 74-1120) 2. National Center for Health Statistics: Vital Statistics. Vital Statistics of the United States. Volume 1: Natality 19501960. Rockville, Md., National Center for Health Statistics 3. National Center for Health Statistics: Monthly Vital Statistics Report: Final Natality Statistics, 1973. Rockville, Md.: National Center for Health Statistics, 1975. (Vol. 23, No. 11, Suppl., January 30) (DHEW publication No. (HRA) 75-1120) 4. National Center for Health Statistics: Monthly Vital Statistics Report: Final Natality Statistics, 1977. Rockville, Md., National Center for Health Statistics, 1979. (Vol. 27, No. 11, Suppl., February 5) (DHEW publication No. (HRA) 79-1120) 5. Baldwin WH: Adolescent pregnancy and childbearing-Growing concerns for Americans. Population Bulletin 31: 2; 1980 update. Washington, D.C., Population Reference Bureau, Inc. 6. O'Connell M, Moore MJ: The legitimacy status of first births: A retrospective study, 1939-42 to 1975-78. Family Plann Perspect 12:1, 1980
September 1980
7. Baldwin W, Cain VS: The children of teenage parents. Family Plann Perspect 12:34-43, 1980 8. Moore KA, Waite LJ, Hofferth SL, Caldwell SB: The consequences of age at first childbirth: Marriage, separation and divorce. Final report to NICHD. Springfield, Va., National Technical Information Service Report No. PB 289053/AS, 1978 9. Forrest JD, Sullivan E, Tietze C: Abortion in the United States, 1977-1978. Family Plann Perspect 11:329-341, 1979
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59
10. Center for Disease Control: AbQrtion Surveillance, 1977. Atlanta, Ga., Center for Disease Control, September 1979 11. Zelnik M, Kantner JF: Sexual and contraceptive experience of young unmarried women. Family Plann Perspect 9:55-71, 1977 12. Zabin LS, Kantner JF, Zelnik M: The risk of adolescent pregnancy in the first months of intercourse. Family Plann Perspect 11:215-222, 1979