Gender-based violence is a key health risk for women globally and in South Africa. The authors analyzed data from 1,395 interviews with women attending antenatal clinics in Soweto, South Africa, between November 2001 and April 2002 to estimate the prevalence of physical/sexual partner violence (55.5%), adult sexual assault by nonpartners (7.9%), child sexual assault (8.0%), and forced first intercourse (7.3%). Age at first experience of each type of violence was modeled by the Kaplan-Meier method, and Cox hazard models with time-varying covariates were used to explore whether child sexual assault and forced first intercourse were associated with risk of violent revictimization in adulthood. Child sexual assault was associated with increased risk of physical and/or sexual partner violence (risk ratio = 2.43, 95% confidence interval: 1.93, 3.06) and with adult sexual assault by a nonpartner (risk ratio = 2.33, 95% confidence interval: 1.40, 3.89). Forced first intercourse was associated with increased risk of physical and/or sexual partner violence (risk ratio = 2.64, 95% confidence interval: 2.07, 3.38) and nonsignificantly with adult sexual assault by a nonpartner (risk ratio = 2.14, 95% confidence interval: 0.92, 4.98). This study confirms the need for increased attention by the public health community to primary and secondary prevention of gender-based violence, with a specific need to reduce risk among South African adolescents.