The use of gonadotropin-releasing hormone (GnRH) agonist to induce oocyte maturation after cotreatment with GnRH antagonist in high-risk patients undergoing in vitro fertilization prevents the risk of ovarian hyperstimulation syndrome: a prospective randomized controlled study - Engmann, L; DiLuigi, A; Schmidt, D; Nulsen, J; Maier, D; Benadiva, C (Fertil Steril, 2008)