1. Perinatology Research Branch; Division of Obstetrics and Maternal-Fetal Medicine; Division of Intramural Research; Eunice Kennedy Shriver National Institute of Child Health and Human Development; National Institutes of Health; U. S. Department of Health and Human Services; Bethesda, Maryland, and Detroit Michigan
2. Department of Obstetrics and Gynecology; Wayne State University School of Medicine; Detroit Michigan
3. Department of Obstetrics and Gynecology; University of Michigan; Ann Arbor Michigan
4. Department of Epidemiology and Biostatistics; Michigan State University; East Lansing Michigan
5. Center for Molecular Medicine and Genetics; Wayne State University; Detroit Michigan
6. Department of Physiology; Wayne State University School of Medicine; Detroit Michigan
7. Department of Immunology, Microbiology and Biochemistry; Wayne State University School of Medicine; Detroit Michigan