This study examined the relationship between self-esteem in adolescence and later risky sexual behavior and pregnancy in late adolescence and early adulthood. The investigation analyzed data from a birth cohort of over 1,000 New Zealand young adults studied to the age of 25. Lower levels of self-esteem at age 15 were associated with greater risks of engaging in unprotected sex (sexual intercourse with either an opposite- or same-sex partner without using a condom), a greater number of sexual partners, and a greater risk of pregnancy at ages 15-25. Adjustment for potentially confounding factors, including family socioeconomic background, family functioning, child abuse, and individual characteristics and behavior, reduced the strength of these associations to statistically non-significant levels. It was concluded that the effects of self-esteem during adolescence on later risky sexual behavior and pregnancy were weak and largely explained by the psychosocial context within which self-esteem develops.