Seeber Beata, Driscoll Deborah A
Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania 19104, USA.
J Pediatr Adolesc Gynecol. 2004 Jun;17(3):161-7. doi: 10.1016/j.jpag.2004.03.042.