1. Pathology (C.K.), St. Louis, Missouri 63110;
2. Departments of Obstetrics/Gynecology (R.A., S.S., K.H.M.), St. Louis, Missouri 63110;
3. Pediatrics (M.O.C.), Washington University School of Medicine, St. Louis, Missouri 63110;
4. Department of Physiology (A.M., C.I.C.), University of Alberta, Edmonton, Alberta, Canada T6G 2H7