A double-blind, non-inferiority RCT comparing corifollitropin alfa and recombinant FSH during the first seven days of ovarian stimulation using a GnRH antagonist protocol - Devroey, P; Boostanfar, R; Koper, N P; Mannaerts, B M; Ijzerman-Boon, P C; Fauser, B C; ENGAGE Investigators (Hum Reprod, 2009)