1. Stellenbosch University and Tygerberg Hospital; Department of Obstetrics and Gynaecology, Faculty of Health Sciences; PO Box 19063 Tygerberg Western Cape South Africa 7505
2. The University of Liverpool; Cochrane Pregnancy and Childbirth Group, Department of Women's and Children's Health; First Floor, Liverpool Women's NHS Foundation Trust Crown Street Liverpool UK L8 7SS
3. University of Ulster; Maternal, Fetal and Infant Research Centre, Institute of Nursing Research; Jordanstown Newtownabbey Northern Ireland UK BT37 0QB
4. Walter Sisulu University, University of the Witwatersrand, Eastern Cape Department of Health; East London South Africa