This study examines changes over time in the prevalence of select sexual behaviors and contraceptive use measures in a national sample of U.S. adolescents.

Study Design
We used data on adolescents aged 15-19 from the 2006-2010 (n=4,662), 2011-2015 (n=4,134), and 2015-2019 (n=3,182) National Surveys of Family Growth. We used logistic regression to identify changes between periods in sexual behaviors and contraceptive use by gender, and for some measures by age. We estimated probabilities of age at first penile-vaginal intercourse with Kaplan-Meier failure analysis.

Over half of adolescents have engaged in at least one of the sexual behaviors measured. Males reported declines in sexual behaviors with a partner of a different sex. Adolescent males reported delays in the timing of first penile-vaginal intercourse. Adolescent females reported increases from 2006-2010 to 2015-2019 in use at last intercourse of any contraceptive method (86%, 95%CI 83-89; 91%, 95%CI 88-94), multiple methods (26%, 95%CI 22-31; 36%, 95%CI 30-43), and IUDs or implants (3%, 95%CI 1-4; 15%, 95%CI 11-20). Adolescent males reported increases in partners' use of IUDs or implants use from <1% to 5% and recent declines in condom use at last intercourse (78%, 95%CI 75-82, 2011-2015; 72%, 95%CI 67-77, 2015-2019). Condom consistency declined over time. Males were more likely than females to report condom use at last intercourse and consistent condom use in the last 12 months.

These findings identify declines in male adolescent sexual experience, increased contraceptive use overall, and declines in consistent condom use from 2006 to 2019.

This analysis contributes a timely update on adolescent sexual behavior trends and contraceptive use, showing that adolescent behaviors are complex and evolving. Sexual health information and services must be available so that young people have the resources to make healthy and responsible choices for themselves and their partners.