[1] Univ Iowa Hosp & Clin, Div Reprod Endocrinol & Infertil, Dept Obstet & Gynecol, Iowa City, IA 52246 USA
[2] Eunice Kennedy Shriver Natl Inst Child Hlth & Hum, Program Reprod & Adult Endocrinol, NIH, Bethesda, MD USA
[3] Northwestern Univ, Prentice Womens Hosp, Dept Obstet & Gynecol, Chicago, IL 60611 USA
[4] Walter Reed Army Med Ctr, Assisted Reprod Technol Program, Div Reprod Endocrinol & Infertil, Washington, DC 20307 USA