The dramatic overall decrease in rates of pregnancies and births to American teenagers over the last few decades should be counted among contemporary success stories in systematic efforts to reduce bio-psychosocial risks to youth. Since the modern peak in 1991, fertility among all major racial and ethnic groups of teens has, with a few brief reversals, steadily and sharply declined: births by about 64% and pregnancies 55% [1]. Though the rate of births to teens remains among the highest in developed nations, approaching twice that of the next-highest, the U.K., the consistency of the trends suggests that the modern tide of high-risk sexual activity associated with unplanned conception among ever-younger American youth has been at least somewhat curtailed [1]. While we see broad changes in young people's sexual behavior that resulted in reduced risk overall of unplanned pregnancy and childbearing, continuing stark disparities in the incidence of early pregnancy among adolescents reveal the profound impact of social and economic inequality on youth's wellbeing in American society. For example, despite within-group declines, Latinas, African American and Native American girls continue to face disproportionate risk of pregnancy; births to teens in impoverished rural areas have risen sharply; and girls in foster care are twice as likely to give birth as those in the general population [2,3]. The clear association of teen pregnancy and childbearing with the complex dimensions of disadvantage led Sarah Brown, former Director of the National Campaign to Prevent Teen and Unplanned Pregnancy to observe that we may already have achieved the "easy wins" in bringing down rates of pregnancy and childbearing among American adolescents [2]. After several years of significant public investments in reducing fertility among teenagers though research, policy, services, and education, the result is that more teens are delaying sexual initiation; many teens are less sexually active; more of those teens who do have sex use contraception effectively; and many of those teens who become pregnant have abortions. Though there remain both empirically-and ideologically-based debates over the relative value of abstinence-only interventions and comprehensive sex education, research suggests that many teenage pregnancy prevention programs are quite effective, and that some programs are more effective for certain teens than for others. That is, if we employ a comprehensive and multi-faceted rather than one-size-fits-all strategy to preventing teen pregnancy, we have significant impact on diverse youth's sexual behavior. The largest proportion of adolescents falls into whom Brown includes as the "easy wins". In other words, the category of youth who were, and remain, at lowest risk of early conception have benefitted most from efforts at teen pregnancy prevention, while others at higher risk will require interventions that target more closely the particular sources of their vulnerability. Most American teenagers are unlikely to become parents bec...