1. 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
2. Université de Montréal; Département d'Obstétrique-Gynécologie; Hôpital Sainte-Justine, Bureau 4974 3175 Chemin de la côte Sainte-Catherine Montréal Province of Quebec Canada H3T 1C5
3. Michigan State University School of Medicine/Sparrow Hospital; Department of Obstetrics and Gynecology; 1322 East Michigan Avenue Suite 220 Lansing Michigan USA 48912