Despite recent declines, the teen birth rate in the United States is still the highest among high-income countries. Immigrant youth can be expected to increasingly shape US trends in adolescent childbearing as their share of the youth population continues to grow. About one in four US children has foreign-born parents currently, up from 6% in 1960; this share is projected to rise to one-third by 2050. In this talk, Goldberg will explain how she used data from the National Longitudinal Study of Adolescent Health (Add Health) to examine how the risk of early childbearing varies by immigrant generation; to what extent generational variation reflects discrepancies in the timing of sexual onset (versus post onset factors); and what family, neighborhood, and individual-level social factors underlie generational differences. She will also describe a new data collection project called the mDiary Study of Adolescent Relationships, which pairs a year-long diary study with an ongoing birth cohort study to increase understanding of the content and quality of teen partnerships over time, and of the childhood precursors and health and developmental consequences of teen relationship behavior.