Cohort profile: Rahima Moosa Mother and Child Hospital maternal HIV cohort, Johannesburg, South Africa.

Purpose: The Rahima Moosa Mother and Child Hospital (RMMCH) maternal HIV cohort originated from data systems that were developed to support HIV-related birth care and track outcomes of a complete birth cohort of HIV-exposed infants at Rahima Moosa Hospital and their mothers living with HIV.

Participants: Supported by the Empilweni Services and Research Unit, maternal and infant data from 13 654 pregnant women living with HIV who delivered their infants (and a subset also attended antenatal care) were collected at RMMCH in Johannesburg, South Africa since 2013. Maternal data were collected using counsellor-administered interviews and the 2013-2018 subset of this cohort was linked to the National Health Laboratory Services (NHLS) national HIV cohort-a longitudinal cohort of people living with HIV accessing care in the public sector antiretroviral therapy programme in South Africa that can observe national access to HIV care through laboratory testing data.