Impact of luteal phase support on pregnancy rates in intrauterine insemination cycles: a prospective randomized study

Objective: To determine the impact of luteal phase support on pregnancy rates in ovarian stimulation and intrauterine insemination (IUI) cycles with gonadotropins in couples with unexplained infertility. Design: Prospective randomized controlled trial. Setting: University-based infertility clinic. Patient(s): Two hundred fourteen couples with unexplained infertility who were treated during 427 ovarian stimulation and IUI cycles with recombinant FSH. Intervention(s): Patients underwent ovarian stimulation with recombinant FSH combined with IUI. Patients randomized into the study group (n = 109) received luteal phase support in the form of vaginal progesterone gel (Crinone 8% gel). Patients randomized into the control group (n = 105) received no luteal phase support. Main Outcome Measure(s): Clinical pregnancy and live birth rate per cycle and per patient. Result(S): Demographic data were found to be homogeneous between the study and control groups. Clinical pregnancy rates per cycle and per patient were significantly higher in the study group (21.1% and 39.4%, respectively) compared with the control group (12.7% and 23.8%, respectively). Live birth rate per cycle and per patient was also significantly higher in patients with luteal support (17.4% and 35.8%, respectively) compared with control subjects (9.3% and 18.1%, respectively). Conclusion(s): Luteal phase support with vaginal progesterone gel significantly affects the success of ovarian stimulation and IUI cycles in patients with unexplained infertility. (Fertil Steril (R) 2009;91:2508-13. (c) 2009 by American Society for Reproductive Medicine.)