Letrozole Versus Recombinant FSH in Ovulation Induction for Intrauterine Insemination in Patients With Polycystic Ovarian Syndrome

Abstract

To compare the efficiency of the aromatase inhibitor Letrozole with follicle-stimulating hormone (FSH) , for ovulation induction in patients with polycystic ovarian syndrome (PCOS) undergoing intrauterine insemination (IUI). Monocentric comparative retrospective study. Analysis of 106 cycles of IUI performed in our institution between January 1st, 2003 and December 31st, 2004 in patients with PCOS (according to the Rotterdam consensus parameters). Of them, 31 cycles used Letrozole for ovulation induction and 75 cycles employed recombinant FSH. The Letrozole cycles were induced with 5 mg a day, starting on day 2 or day 3 of cycle for 5 days. Recombinant FSH cycles were induced with a daily dosis of 50 -150 IU/day according to patient’s body mass index from cycle day 3 until hCG administration. HGC was given when a leading follicle reached 17 mm of mean diameter. Two IUIs were performed, 12 and 36 hours after hCG administration. Cancellation, pregnancy per IUI and per started cycle, multiple pregnancy, miscarriage and take home rates were compared between both groups. No significant differences were observed between both groups in terms of pregnancy rates per started cycle or per IUI, although slightly better outcome was obtained with letrozole. However, as cancellation and miscarriage rates were higher (although not significant) in the Letrozole group, the take home baby rate per started cycle was comparable between both groups. Tabled 1 The use of Letrozole for ovulation induction in PCOS women for IUI provides similar outcome in terms of take home baby rate per started cycle than the use of recombinant FSH.