South African young people face numerous challenges as they prepare for adulthood. High levels of household chaos and sexual and physical violence are common and many young people get pregnant and take risks with sexual activity. Trauma and other disruptions during this life stage can have an especially strong influence on future life chances because of their potential to interfere with the preparation for adult roles. This interference can constrain ones' possibilities for education, employment, and family formation, with clear economic and social consequences. Thus, understanding how such experiences influence young people's decisions about sexual behavior and childbearing is important to understanding how social inequality is perpetuated.

The three papers in this dissertation examine how two types of trauma and disruption-household economic and contextual shocks and sexual coercion-influence the sexual and reproductive behavior of South African young people, and investigates whether neighborhood characteristics moderate some of these influences. In particular, I examine: 1) whether household shocks, such as parental job loss or divorce, influence three sexual behaviors with particular relevance to the increased risk of HIV infection; 2) whether neighborhood collective efficacy moderates the influence of household shocks on sexual behavior; and 3) whether the causal relationship between sexual coercion and adolescent pregnancy suggested by previous work is supported by more methodologically rigorous tests. I integrate approaches from sociology, economics, psychology, and public health, capitalizing on the strengths of each discipline and further our understanding of factors influencing the wellbeing of adolescents and young adults. Moreover, I use appropriate statistical methods to conduct more robust tests of these influences than previous research has included. My findings have implications for research on social inequality, resilience, and the health and wellbeing of adolescents and young adults, as well as for policy and prevention efforts.