Academic achievement and cognitive ability have been shown to predict later age at first sexual intercourse. Using a sample of 536 same-sex twin pairs who were followed longitudinally from adolescence to early adulthood, this study tested whether relations between intelligence, academic achievement, and age at first sex were due to unmeasured…

Transactional models of problem behavior argue that less effective parenting and adolescent problem behaviors coevolve, exerting bidirectional influences. This article extends such models by analyzing growth trajectories of sexual risk behaviors and parenting processes among 3,206 adolescents (aged 13-18) and their residential parents. Within…

Longitudinal studies in two countries investigated impact of father absence on girls' early sexual activity (ESA) and teenage pregnancy. Findings indicated that greater exposure to father absence strongly related to elevated ESA and adolescent pregnancy risk. Elevated risk was not explained (U.S. sample) or only partly explained (New Zealand…

Studied the social networks and daily activities of children and adolescents living or working on the streets of Belo Horizonte, Brazil. Found that youngsters who lived at home and worked on the street appeared to be experiencing orderly development despite their impoverished circumstances. Youngsters who lived on the streets, however, showed…