Assessing Adolescent Pregnancy - Maine, 1980-1996

Morbidity and Mortality Weekly Report, June 5, 1998

Maine vital statistics data for 1980-1996 were used to assess adolescent pregnancies, births, and abortions by age, marital status, education, partner's age, and previous pregnancies. Annual reports from FPA, the only recipient of Title X funds in Maine and the largest provider of reproductive health-care services in the state, were used to examine clinical factors that may have contributed to decreasing adolescent pregnancy rates (e.g., what contraceptive methods clients reported using). The Maine Pregnancy Risk Assessment Monitoring System (PRAMS), a survey of new mothers about pregnancy behaviors, practices, and outcomes, was used to determine the number and rate of unintended pregnancies among adolescents who gave birth. Chlamydia rates from the MBH Sexually Transmitted Diseases Surveillance System were used as a proxy indicator to help evaluate trends in unprotected Intercourse among adolescents. The Maine Youth Risk Factor Behavior Survey, a survey of adolescents in grades 9-12, was used to obtain inf ormation about adolescent sexual behavior. Data from the Maine Department of Education were used to assess high school drop-out rates and the percentage of high school seniors who intended to pursue postsecondary education.

Adolescent pregnancy rates were calculated as the total reported live-born infants, abortions, and fetal deaths per 1000 females in Maine for females aged 15-17, 18-19, and 15-19 years (3); fetal losses at <20 weeks' gestation were not included. Population data are from the MBH, Office of Data, Research and Vital Statistics. Trends in adolescent pregnancy, birth, and abortion rates were tabulated by demographic variables, and changes in potential explanatory variables were examined overtime. Correlation coefficients (r) and p values were used to assess the strength and significance of correlations between these factors and adolescent pregnancy rates.

From 1980 through 1996, pregnancy rates in Maine among females aged 15- 19 years decreased from 67.9 to 45.6 pregnancies per 1000; the largest decrease occurred from 1991 to 1992 (Table 1, Figure 1). Both birth and abortion rates decreased among females aged 15-17 and 18-19 years. Among females aged 15-19 years, the percentage of pregnancies among those who were unmarried increased from 58% to 83%, while the percentage of pregnancies among those with a previous pregnancy decreased from 29% to 24%. There were no substantial changes in mean years of education or partner's age among adolescents who became pregnant.

From 1984 through 1996, the percentage of females aged 15-19 years who were seen at FPA clinics was approximately 22% per year (Table 1). OCs have been the predominant family planning method of adolescents at the FPA clinics, but the percentage using OCs declined from 75% to 58%. Condom use increased from 5% to 14%, and the use of long-acting contraceptive methods (primarily [Norplant.sup.(r)$] [Wyeth-Ayerst, Philadelphia, Pennsylvania] and [Depo-Provera.sup.(r)] [The Upjohn Company, Kalamazoo, Michigan]) increased from <1% to 11%. Both the decrease in OC use and the increase in use of condoms and long-acting contraceptive methods among FPA clients were significantly correlated with the decrease in adolescent pregnancy rates from 1984 to 1996 (r=0.76 -0.85, and -0.77, respectively).

Changes in some behavioral factors also were significantly correlated with the decrease in adolescent pregnancy rates. From 1988 to 1996, rates for chlamydia among females aged 15-19 years (a proxy for having unprotected intercourse) decreased from 27 to eight cases per 1000 (correlation with decrease in adolescent pregnancy rates: r-0.96). From 1989 to 1996, unintended pregnancies among adolescent females who gave birth increased from 85% to 77% (correlation with decrease in adolescent pregnancy rates: r=-0.77). Among males and females, from 1980 to 1996, the high school dropout rate decreased from 4% to 3% (correlation with decrease in adolescent pregnancy rates: r=0.74), and the percentage of high school seniors who indicated a goal to pursue postsecondary education increased from 45% to 62% (correlation with decrease in adolescent pregnancy rates: r=-0.57). The percentage of males and females aged 15-19 years who had ever had sexual intercourse was 58% in 1991 49% in 1995, and 52% in 1997; the changes in these percentages were not statistically significant.

Reported by: E Kieltyka, Family Planning Association of Maine, Augusta; J Foster, F Antonicci, Maine Dept of Education; F Wolman, MD, 0 Hall, MN, B Corkum, DA Mills, MD, Bur of Health, Maine Dept of Human Svs, Div of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion; Div of Health Promotion Statistics, National Center for Health Statistics; Div of Applied Public Health and Training (proposed), Epidemiology Program Office; and an EIS Officer, CDC.

Editorial Note: A thorough assessment of factors influencing adolescent pregnancy rates at the state level can be used to target adolescent pregnancy prevention efforts and evaluate progress toward national health objectives for 2000. This retrospective assessment of pregnancy rates among adolescents in Maine illustrates how states can identify trends in adolescent pregnancy rates and associated factors. In Maine, changes in behavioral factors may have had the greatest impact on adolescent pregnancy rates, including increased condom use, decreased high school drop-out rates, and increased intent to pursue postsecondary education. The use of long-acting contraceptive methods was rare before 1993 and therefore could not have contributed to the large decrease in adolescent pregnancy rates from 1991 to 1992. Decreases in rates for chlamydia may indicate a decrease in the incidence of unprotected intercourse among this group.