Sexual violence at first intercourse against women in Moshi, northern Tanzania: prevalence, risk factors, and consequences.

To explore the relationship between sexual violence at first intercourse and later sexually transmitted infections (STIs) in Moshi, Tanzania, we analysed data from a representative household survey that comprised face-to-face interviews with 1,835 women and tests for six STIs on biological samples from 1,235 of these women. Overall, 10.9 per cent report forced first intercourse and 15.3 per cent report unwanted first intercourse. Unadjusted analysis shows a relationship between forced first intercourse and STIs (OR: 1.72, 95 per cent CI: 1.19-2.51). Life-course variables mediate this relationship. Significant predictors of having an STI include older age, more sexual partners, and a partner who has children with other women. Coerced first intercourse appears to be associated with changes in the life course of women and with a heightened risk of contracting an STI.