From the Department of Obstetrics, Gynecology and Reprodutive Sciences, University of California, San Francisco, San Francisco, California; the Department of Obstetrics and Gynecology, Oregon Health and Science University, Portland, Oregon; and the Department of Family Medicine and Community Health, University of Pennsylvania, Philadelphia, Pennsylvania.
Dr. Cheng is supported by the Eunice Kennedy Shriver National Institute of Child Health and Human Development, Grant # HD01262, as a Women's Reproductive Health Research Scholar.
Presented at the 31st Annual Meeting of the Society for Maternal Fetal Medicine, February 7–12, 2011, San Francisco, California.
Corresponding author: Melissa G. Rosenstein, MD, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, 505 Parnassus Avenue, Box 0132, San Francisco, CA 94143; e-mail: [email protected].
Financial Disclosure The authors did not report any potential conflicts of interest.
