Mm6013.pdf

Vital Signs: Teen Pregnancy — United States, 1991–2009
On April 5, this report was posted as an MMWR Early Release on the MMWR website (http://www.cdc.gov/mmwr). ABSTRACT
Background: In 2009, approximately 410,000 teens aged 15–19 years gave birth in the United States, and the teen birth
rate remains higher than in other developed countries.
Methods: To describe U.S. trends in teen births and related factors, CDC used data on 1) teen birth rates during 1991–
2009 from the National Vital Statistics System, 2) sexual intercourse and contraceptive use among high school students
during 1991–2009 from the national Youth Risk Behavior Survey, and 3) sex education, parent communication, use of
long-acting reversible contraceptives (LARCs), and receipt of reproductive health services among teens aged 15–19 years
from the 2006–2008 National Survey of Family Growth.
Results: In 2009, the national teen birth rate was 39.1 births per 1,000 females, a 37% decrease from 61.8 births per
1,000 females in 1991 and the lowest rate ever recorded. State-specific teen birth rates varied from 16.4 to 64.2 births
per 1,000 females and were highest among southern states. Birth rates for black and Hispanic teens were 59.0 and 70.1
births per 1,000 females, respectively, compared with 25.6 for white teens. From 1991 to 2009, the percentage of high
school students who ever had sexual intercourse decreased from 54% to 46%, and the percentage of students who had
sexual intercourse in the past 3 months but did not use any method of contraception at last sexual intercourse decreased
from 16% to 12%. From 1999 to 2009, the percentage of students who had sexual intercourse in the past 3 months
and used dual methods at last sexual intercourse (condoms with either birth control pills or the injectable contraceptive
Depo-Provera) increased from 5% to 9%. During 2006–2008, 65% of female teens and 53% of male teens received
formal sex education that covered saying no to sex and provided information on methods of birth control. Overall, 44%
of female teens and 27% of male teens had spoken with their parents about both topics, but among teens who had ever
had sexual intercourse, 20% of females and 31% of males had not spoken with their parents about either topic. Only
2% of females who had sexual intercourse in the past 3 months used LARCs at last sexual intercourse.
Conclusions: Teen birth rates in the United States have declined but remain high, especially among black and Hispanic
teens and in southern states. Fewer high school students are having sexual intercourse, and more sexually active students
are using some method of contraception. However, many teens who have had sexual intercourse have not spoken with
their parents about sex, and use of LARCs remains rare.
Implications for Public Health Practice: Teen childbearing is associated with adverse consequences for mothers and
their children and imposes high public sector costs. Prevention of teen pregnancy requires evidence-based sex education,
support for parents in talking with their children about pregnancy prevention and other aspects of sexual and reproduc-
tive health, and ready access to effective and affordable contraception for teens who are sexually active.
Introduction
greater risk for low birth weight, preterm birth, and death in infancy (5,6). Teen childbearing also perpetuates a cycle of Despite declines since 1991 (1), the teen birth rate in the disadvantage; teen mothers are less likely to finish high school, United States remains as much as nine times higher as in and their children are more likely to have low school achieve- other developed countries (2),* and significant racial/ethnic ment, drop out of high school, and give birth themselves as and geographic disparities exist in the United States (3,4). teens (7,8). Each year, teen childbearing costs the United States Compared with births to adult women, births to teens are at approximately $6 billion in lost tax revenue and nearly $3 billion in public expenditures. However, these costs are $6.7 * By comparison, the U.S. teen birth rate is nearly one and a half times higher than the teen birth rate in the United Kingdom, which has the highest teen billion lower than they would have been had teen childbearing birth rate in western Europe. The U.S. rate is nearly three times higher than the teen birth rate in Canada and six to nine times higher than the teen birth rates in Denmark, the Netherlands, Sweden, and Switzerland (2).
This report describes trends in birth rates among U.S. teens NSFG is an in-person, household survey based on a strati- aged 15–19 years and percentages of high school students fied, multistage probability sample that is nationally represen- having sexual intercourse and using contraceptives. The tative of eligible women and men aged 15–44 years. For this prevalence of four measures with the potential to reduce teen report, 2006–2008 data were used to examine the prevalence pregnancy (i.e., sex education, communication with parents, of receiving sex education, parental communication, use of use of long-acting reversible contraceptives, and receipt of long-acting reversible contraceptives (LARCs) and receipt of reproductive health services) (10–14) also are examined among reproductive health services, among never-married teens aged 15–19 years (16,19). LARCs were defined as intrauterine devices and contraceptive implants (Norplant and Implanon) (14). Receipt of reproductive health services was measured in Data sources were natality files from the National Vital terms of whether female teens had received a method of birth Statistics System and two nationally representative surveys: the control or a prescription from a health-care provider in the national Youth Risk Behavior Survey (YRBS) and the National preceding 12 months. This measure was evaluated because Survey of Family Growth (NSFG). U.S. natality files are com- females can only obtain LARCs and other hormonal methods¶ piled annually and include demographic information such as maternal age, race, and Hispanic origin for all births in the United States. This report includes preliminary national and state-specific data for 2009 (which include 99.95% of all births Teen birth rates. In 2009, approximately 410,000 births
during that year) (15) and final data from 1991–2008 (1,3,5). occurred among teens aged 15–19 years; the teen birth rate YRBS is a school-based, self-administered survey conducted fell to 39.1 births per 1,000 females, a 37% decrease from by CDC using a multistage cluster sample to obtain data rep- 61.8 births per 1,000 females in 1991 and the lowest rate ever resentative of students in grades 9–12 attending private and recorded. During that period, the birth rate decreased 50% public schools in the United States. In this report, 1991–2009 among black teens, 41% among white teens, and 33% among data were used to assess the percentage of students who ever Hispanic teens. In 2009, birth rates for black teens (59.0 per had sexual intercourse and the percentage of currently sexually 1,000 females) and Hispanic teens (70.1 per 1,000 females) active students† who did not use any method of contracep- were more than twice that of white teens (25.6 per 1,000 tion at last sexual intercourse. Use of selected contraceptive females). Although birth rates were higher among black teens methods§ at last sexual intercourse among sexually active than Hispanic teens during 1991–1994, Hispanic teens had students was assessed from 1999, the first year that use of the higher birth rates during 1995–2009 (Figure). injectable contraceptive Depo-Provera was measured, through In 2009, birth rates were lowest in the Northeast and upper 2009. In addition, because research has shown that many Midwest and highest among southern states. State-specific birth youths do not use condoms consistently (16) and use of an rates varied from 16.4 to 22.7 births per 1,000 females aged additional birth control method is recommended (17), dual 15–19 years in states with the lowest birth rates (Connecticut, method use (i.e., condoms with birth control pills or Depo- Massachusetts, New Hampshire, New Jersey and Vermont), Provera) was assessed. Temporal changes were analyzed overall to 59.3 to 64.2 births per 1,000 females aged 15–19 years in and by sex and race/ethnicity using logistic regression analyses states with the highest birth rates (Arkansas, Mississippi, New that simultaneously assessed linear and quadratic (e.g., level- Mexico, Oklahoma, and Texas).** Birth rates for white and ing off or change in direction) time effects (18). Racial/ethnic Hispanic teens have been highest in the Southeast, whereas data are presented only for black (non-Hispanic), white (non- birth rates for black teens have been highest in the upper Hispanic), and Hispanic students (of any race); the numbers of students from other racial/ethnic groups were too small for Sexual behavior and use of contraception. In 2009, 46%
of high school students reported ever having had sexual inter-course, a decrease from 54% in 1991. In 2009, for female † Students were considered currently sexually active if they had sexual intercourse with at least one person during the 3 months before the survey. ¶ NSFG measures use of the following methods that have been classified in this § Use of the following selected contraceptive methods among sexually active report as hormonal contraceptives: birth control pills, the injectable contracep- students was assessed: 1) condoms but not birth control pills or Depo-Provera; tives Depo-Provera and Lunelle, and contraceptive patches and rings. The 2) birth control pills or Depo-Provera but not condoms; and 3) dual methods contraceptive implants Norplant and Implanon and the intrauterine device (condoms and birth control pills or Depo-Provera). The percentage of students Mirena also contain hormones but are classified in this report as LARCs.
who used methods other than condoms, birth control pills, or Depo-Provera ** Information available at http://www.cdc.gov/mmwr/preview/mmwrhtml/ FIGURE. Birth rate for teens aged 15–19 years, by race/ethnicity* — National Vital Statistics System, United States, 1991–2009
Sources: Hamilton BE, Martin JA, Ventura SJ. Births: preliminary data for 2009. Natl Vital Stat Rep 2010;59(3). Martin JA, Hamilton BE, Sutton PD, et al. Births: final data
for 2008. Natl Vital Stat Rep 2010;59(1).
* Persons categorized as black or white were non-Hispanic. Persons categorized as Hispanic might be of any race.
students, the percentage who ever had sexual intercourse was In 2009, 44% of sexually active female students and 60% highest among black students (58%) and similar among white of sexually active male students used condoms at last sexual (45%) and Hispanic students (45%). For male students, the intercourse. Among sexually active female students, 18% used percentage who ever had sexual intercourse was higher among birth control pills or Depo-Provera without condoms, and 10% black students (72%) than Hispanic (53%) and white students used dual methods (i.e., condoms with birth control pills or (40%) and higher among Hispanic than white students. During Depo-Provera). Among sexually active male students, 10% 1991–2009, the overall percentage of female and male students did not use a condom but their partner used birth control who ever had sexual intercourse decreased; however, this decrease pills or Depo-Provera, and 8% used dual methods in which did not occur among white female students, Hispanic female they used a condom and their partner used birth control pills or students, or Hispanic male students, and beginning in 2001, the Depo-Provera. During 1999–2009, condom use without birth decrease among black male students leveled off (Table 1). control pills or Depo-Provera remained the most commonly used In 2009, 12% of sexually active students did not use any method contraceptive method; the percentage of students who used dual of contraception at last sexual intercourse, a decrease from 16% in methods (condoms with birth control pills or Depo-Provera) was 1991. In 2009, both for female and male students, the percent- low, but increased from 5% in 1999 to 9% in 2009. However, age who did not use any method of contraception at last sexual whereas this increase occurred among male and female students intercourse was higher among Hispanic students (females, 23%; overall, it was only observed among white students (Table 1). males, 16%) and black students (females, 20%; males, 12%) than During 2006–2008, use of long-acting reversible contraceptives white students (females, 10%; males, 6%). During 1991–2009, (LARCs) (i.e., intrauterine devices and contraceptive implants) the overall percentage of sexually active female and male students was rare (16). Only 2% of sexually active females aged 15–19 years who did not use contraception at last sexual intercourse decreased. reported using one of these methods at last intercourse. This decrease occurred for female and male students in every racial/ Sex education, parent communication, and receipt of services.
ethnic group, but for black female students, the decrease leveled During 2006–2008, most teens said they had received formal sex education before age 18 years that either covered saying no to sex TABLE 1. Percentage of high school students who reported pregnancy risk behaviors and contraceptive use, by sex and race/ethnicity* — Youth
Risk Behavior Survey, United States, 1991–2009
Race/Ethnicity
Hispanic
Behavior/Year
Ever had sexual intercourse
(46.7–54.9)
(47.5–52.8)
(46.9–57.2)
(43.9–51.5)
(43.5–51.9)
(40.1–45.8)
(42.6–48.0)
(42.0–49.4)
(43.1–48.6)
(43.0–48.5)†
Did not use any method of contraceptive¶,**
(15.7–20.7)
(14.1–18.5)
(14.6–20.4)
(13.1–17.0)
(13.8–19.9)
(12.5–17.0)
(10.1–14.3)
(12.8–16.5)
(11.8–16.5)
(12.1–15.9)†
Used condoms††
(37.9–50.5)
(40.0–46.9)
(45.7–52.0)
(43.8–49.9)
(44.3–50.5)
(40.9–46.4)§
Used birth control pills or Depo-Provera§§
(16.5–22.6)
(17.2–21.6)
(14.9–21.0)
(13.4–19.5)
(13.5–18.5)
(15.0–20.5)
Used dual methods¶¶
(4.6–7.8)
(6.3–8.9)
(6.2–10.2)
(7.1–10.0)
(6.3–8.8)
(7.9–12.1)†
(females, 87%; males, 81%) or provided information on methods about either topic. The percentage of teens who spoke with of birth control (females, 70%; males, 62%); 65% of females and their parents about methods of birth control was higher among 53% of males received education on both topics (Table 2). Among those who had ever had sexual intercourse (females, 70%; teens who had ever had sexual intercourse, 5% of females and 13% males, 64%) than among those who had not (females, 48%; of males had received no formal education on either topic. males 35%) (Table 2). However, among those who had ever Approximately half of all teens had spoken with their parents had sexual intercourse, 20% of females and 31% of males had either about how to say no to sex or about methods of birth never spoken with their parents either about how to say no to control†† (Table 2). Fewer teens (females, 44%; males, 27%) sex or about methods of birth control.
had spoken with their parents about both topics, and 24% of Among sexually active females, during 2006–2008, 55% females and 38% of males had not spoken with their parents (95% confidence interval [CI] = 48%–63%) either had received a method of birth control or a prescription from a health-care †† Includes communicating with parents about contraception, methods of birth provider in the preceding 12 months; this percentage was higher control, where to get birth control, or how to use a condom.
TABLE 1. (Continued) Percentage of high school students who reported pregnancy risk behaviors and contraceptive use, by sex and race/
ethnicity* — Youth Risk Behavior Survey, United States, 1991–2009
Race/Ethnicity
Combined total for
Hispanic
males and females
Behavior/Year
Ever had sexual intercourse
(53.1–61.5)
(50.5–57.8)
(52.0–59.2)
(50.2–55.8)
(49.0–58.8)
(48.4–57.7)
(45.4–52.3)
(45.2–51.6)
(48.0–56.2)
(46.1–53.7)
(45.8–51.3)
(43.2–48.1)
(44.6–51.4)
(44.0–49.4)
(44.4–51.5)
(43.4–50.2)
(46.7–52.9)
(45.1–50.6)
(41.5–50.9)†
(42.9–49.2)†
Did not use any method of contraceptive¶,**
(12.2–18.3)
(14.6–18.6)
(12.4–16.3)
(13.7–17.0)
(11.6–17.1)
(13.6–18.2)
(12.9–18.0)
(13.5–17.1)
(11.0–15.8)
(13.2–16.8)
(10.1–13.9)
(11.7–15.0)
(8.9–12.3)
(9.9–13.0)
(9.1–12.9)
(11.4–14.3)
(8.8–12.0)
(10.8–13.7)
(8.3–11.4)†
(10.7–13.2)†
Used condoms††
(56.6–65.8)
(48.0–57.0)
(55.1–60.1)
(47.9–52.4)
(60.9–65.9)
(53.5–58.4)
(59.3–66.9)
(52.2–57.4)
(60.6–66.9)
(53.3–57.5)
(57.4–63.0)
(49.3–54.1)§
Used birth control pills or Depo-Provera§§
(6.2–15.5)
(11.8–18.3)
(9.2–12.6)
(13.9–16.8)
(8.6–12.1)
(12.1–16.1)
(8.0–11.9)
(11.0–15.4)
(7.5–11.6)
(11.0–14.6)
(8.7–12.6)
(12.3–16.2)
Used dual methods¶¶
(2.6–4.5)
(3.8–6.0)
(5.7–8.6)
(6.5–8.1)
(4.1–7.2)
(5.6–8.4)
(5.1–8.4)
(6.4–8.8)
(3.6–5.9)
(5.1–7.1)
(6.4–9.5)†
(7.6–10.3)†
Abbreviation: CI = confidence interval.
* Students categorized as black or white were non-Hispanic. Students categorized as Hispanic might be of any race. Other racial/ethnic populations were too small for meaningful
† Significant linear effect.
§ Significant quadratic effect.
¶ At last intercourse among students who had sexual intercourse with at least one person during the 3 months before the survey.
** The percentages of sexually active students who did not use any method of contraception and the percentages who used selected contraceptive methods do not add to 100% because the percentage of students who used methods other than condoms, birth control pills, or Depo-Provera is not assessed in this report.
†† Without birth control pills or the injectable contraceptive, Depo-Provera, at last sexual intercourse among students who had sexual intercourse with at least one person during the 3 §§ Without condoms, at last sexual intercourse among students who had sexual intercourse with at least one person during the 3 months before the survey.
¶¶ Condoms with birth control pills or the injectable contraceptive, Depo-Provera, at last sexual intercourse among students who had sexual intercourse with at least one person during among sexually active teens who had spoken with their parents 12 months, 56% (CI = 47%–64%) reported using a hormonal about birth control (64%; CI = 55%–71%) compared with method (i.e., birth control pills, injectable contraceptives, con- those who had not (37%; CI = 26%–50%). Among those sexu- traceptive patches and rings), or a LARC (i.e., contraceptive ally active females who had received a method of birth control implants and intrauterine devices) at last sexual intercourse. or a prescription from a health-care provider in the preceding TABLE 2. Percentage of never-married teens aged 15–19 years who received formal sex education or talked to their parents about sex, by
sexual intercourse status — National Survey of Family Growth, 2006–2008
Ever had sexual
Never had sexual
Ever had sexual
Never had sexual
intercourse
intercourse
intercourse
intercourse
Education/Parental
communication
Received formal sex education before age 18 years on
(83.4–90.3)
81.1 (78.1–83.7)
69.5 (65.0–73.6)
61.9 (57.6–66.0)
(60.2–68.8)
53.4 (49.6–57.1)
(5.9–10.5)
(8.3–13.1)
Ever spoke to a parent or guardian about
(58.3–66.8)
41.9 (37.2–46.6)
Methods of birth control*
(52.9–61.7)
47.7 (43.6–51.8)
(39.7–48.1)
27.4 (23.2–32.1)
(20.4–27.8)
37.8 (34.1–41.7)
Abbreviation: CI = confidence interval.
* Includes talking with parents about methods of birth control, where to get birth control, or how to use a condom.
Conclusions and Comment
Provera on site or through prescription, the need to be referred The teen birth rate in the United States declined during to another doctor might impede the use of intrauterine devices 1991–2009 to its lowest level in the nearly 70 years these data and contraceptive implants (20). In addition, teens who receive have been collected (1). Nonetheless, in 2009, approximately these methods do not always use them; the findings in this report 410,000, or 4% of all female teens aged 15–19 years, gave birth suggest that only half of sexually active females who received in the United States, and the teen birth rate remains nearly three a method of birth control from a health-care provider used a to four times higher in those states with the highest birth rates LARC or another hormonal method at last intercourse.
(>59 births per 1,000 females), compared with those states with Numerous sex education programs have been shown to be the lowest rates (<23 births per 1,000 females). Moreover, the effective in delaying sexual initiation or increasing contracep- teen birth rate in the United States remains six to nine times tive use (10). Research also has shown that parent-child com- higher than in developed countries with the lowest birth rates. munication can delay sexual initiation and reduce sexual risk Even in U.S. states with the lowest rates, the teen birth rate is behaviors (11–13). Nonetheless, consistent with other recent nearly three to five times higher than in developed countries with publications (19), this report suggests many teens do not the lowest birth rates, and in U.S. states with the highest rates, receive formal sex education that covers both abstinence and the teen birth rate is approximately 10 to 15 times higher than contraception, and many teens do not talk with their parents in other developed countries with the lowest birth rates (2). Paralleling the decline in births to teens aged 15–19 years The findings in this report are subject to at least five limita- during 1991–2009, the percentage of high school students who tions. First, natality data are based on births, not pregnancies, had ever had sexual intercourse and the percentage of sexually and therefore exclude pregnancies that do not result in live active students who did not use any method of contraception at birth. Second, estimates of sexual risk and protective behaviors last sexual intercourse both decreased. However, these decreases (i.e., contraceptive use) are self-reported; the extent of underre- were not consistently observed across all race/ethnicity groups. porting or overreporting cannot be determined and can vary by Moreover, among sexually active high school students, use of sex (e.g., males might be unaware of the contraceptive methods hormonal methods (i.e., birth control pills or the injectable their partners are using). Nonetheless, survey questions dem- contraceptive Depo-Provera), alone or in combination with onstrate good test-retest reliability (21). Third, the findings condoms, remains low. Among teens aged 15–19 years, use of obtained through YRBS are applicable only to youths who LARCs (i.e., intrauterine devices and contraceptive implants), attend school and are not representative of out-of-school teens remains rare. Unlike condoms, use of these methods is limited who might have a higher prevalence of health risk behaviors in part because they must be obtained from a health-care pro- (22). Fourth, although surveys indicate the majority of teen vider; the findings in this report suggest that only half of sexually births are unintended (23), distinguishing unintended from active females receive birth control methods from a health-care intended births is not possible using data from the National provider. Although approximately 98% of health-care providers Vital Statistics System. Finally, this report does not address offer birth control pills and the injectable contraceptive Depo- births to females aged <15 years. In 2009, approximately 5,000 2. United Nations. 2008 Demographic Yearbook. New York, NY: United Key Points
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