1. Geneva Foundation for Medical Education and Research; Chemin Edouard Tavan 5 Geneva Switzerland CH-1206
2. China Welfare Institute; International Peace Maternity and Child Health Hospital (IPMCH); 145 Guangyuan Road 910 Hengshan Road Shanghai China 200030
3. University of Geneva, Switzerland; Department of Obstetrics and Gynaecology; 35, Avenue de Vaudagne Meyrin Geneva Switzerland 1217
4. University of the Witwatersrand, University of Fort Hare, Eastern Cape Department of Health; Department of Obstetrics and Gynaecology, East London Hospital Complex; Frere and Cecilia Makiwane Hospitals Private Bag X 9047 East London Eastern Cape South Africa 5200