1. Department of Obstetrics & Gynecology, University of Michigan, 1500 East Medical Center Drive, L4510, Ann Arbor, MI 48109, USA
2. Unit for Laboratory Animal Medicine, University of Michigan, Ann Arbor, MI 48109, USA
3. College of Literature, Science, and the Arts, University of Michigan, Ann Arbor, MI 48109, USA
4. Reproductive Sciences Program and the Division of Infectious Diseases, Department of Internal Medicine, Department of Microbiology & Immunology, University of Michigan, Ann Arbor, MI 48109, USA
5. Department of Obstetrics & Gynecology, University of Washington, Seattle, WA 98195, USA