INTRODUCTION: There is a growing interest in adolescent motherhood and HIV among policymakers and programme implementers. To better shape services and health outcomes, we need evidence on reproductive aspirations and contraception use in this high-risk group, including the effect of motherhood and HIV status. We report data from a large survey of adolescent girls and young women conducted in a mixed rural-urban district in South Africa. METHODS: Quantitative interviews were conducted with 1712 adolescent girls and young women (ages 10 to 24): 336 adolescent mothers living with HIV (AMLHIV), 454 nulliparous adolescent girls living with HIV (ALHIV), 744 HIV-negative adolescent mothers (control adolescent mothers) and 178 HIV-negative nulliparous adolescent girls (nulliparous controls) in 2018 to 2019. Standardized questionnaires included socio-demographic measures, reproductive health and contraception experiences. Reproductive aspirations were measured as the number of children participants wanted to have. Dual protection was computed as use of both hormonal and barrier contraception or abstinence. Multivariate logistic regression and marginal effects models in STATA 15 were used to test associations between HIV status, adolescent motherhood and outcomes of reproductive aspirations, contraception use and dual protection, controlling for covariates. RESULTS AND DISCUSSION: Nearly 95% of first pregnancies were unintended. Over two-thirds of all participants wanted two or more children. Hormonal contraception, condom use and dual protection were low across all groups. In multivariate regression modelling, ALHIV were less likely to report hormonal contraception use (aOR 0.55 95% CI 0.43 to 0.70 p ≤ 0.001). In marginal effects modelling, adolescent mothers - independent of HIV status - were least likely to report condom use at last sex. Despite higher probabilities of using hormonal contraception, rates of dual protection were low: 17.1% among control adolescent mothers and 12.4% among AMLHIV. Adolescent mothers had the highest probabilities of not using any contraceptive method: 29.0% among control mothers and 23.5% among AMLHIV. CONCLUSIONS: Among adolescent girls and young women in HIV-endemic communities, reproductive aspirations and contraceptive practices affect HIV risk and infection. Tailored adolescent-responsive health services could help young women plan their pregnancies for when they are healthy and well-supported, and help interrupt the cycle of HIV transmission by supporting them to practice dual protection.