1. Department of Sociomedical Sciences, Mailman School of Public Health, Columbia University, 722 W. 168th Street, New York, NY 10032, USA
2. Endo Sisters East Africa Foundation, Laiboni Center, Off Lenana Rd., Nairobi P.O. Box 100798-00101, Kenya
3. Institute of Primate Research, Karen, Nairobi P.O. Box 24481-00502, Kenya
4. The Department of Obstetrics and Gynaecology, Kenyatta National Hospital, Nairobi P.O. Box 20723-00202, Kenya