1. Department of Obstetrics and Gynaecology; University of Pretoria and Steve Biko Academic Hospital; Pretoria South Africa
2. South African Medical Research Council Maternal and Infant Health Care Strategies Unit; Department of Obstetrics and Gynaecology; University of Pretoria; Pretoria South Africa
3. Department of Obstetrics and Gynaecology; University of Pretoria and Kalafong Provincial Tertiary Hospital; Pretoria South Africa