Understanding Generational Differences in Early Fertility: Proximate and Social Determinants.

Although US rates of early fertility have declined, they remain high relative to other high-income countries, and disparities by population group persist. The share of the US youth population with immigrant parents has expanded greatly, yet relatively little is known about generational variations in early fertility. This study used Add Health data to investigate: (1) differences by generational status in the risk of early childbearing; (2) to what extent observed differences reflected timing of sexual onset versus post-onset proximate determinants like contraceptive use; and (3) the influence of individual-, family-, and neighborhood-level social factors. Foreign-born and second-generation young women initiated both sexual activity and childbearing later than those with US-born parents. Sequential hazard models revealed the importance of later sexual onset in explaining delayed fertility among the foreign-born, and of family attributes for their later sexual onset. Post-onset behaviors were central to the delayed childbearing observed among the second generation.