Ovulation induction with letrozole in gonadotrophin stimulation resistant women undergoing in vitro fertilization

Abstract

To assess the clinical outcomes of aromatase inhibitors for stimulating poor responder women undergoing in vitro fertilization (IVF) protocol in whom high doses gonadotrophins treatment was unsuccessful. Retrospective analysis. 37 IVF patients with high basal concentrations of FSH(>13 mIU/mL) who had shown no response to vigorous gonadotrophin stimulation are reported. Patients were offered letrozole, 5 mg/day for 5 consecutive days starting on day 3 of the menstrual cycle. Ultrasonography was performed before initiation of treatment, on day 9 of menstrual cycle, and as required thereafter until the dominant follicle reached 18 mm in diameter. Ovulation was triggered with 10,000 IU of hCG, and oocyte pick-up was performed 34–36 hours later. Sixteen cycles (42%) were canceled because of no ovarian response. Five patients (24%) did not have IVF because of no oocyte retrieval. And four patients did not have ET because of failed fertilization. Twelve patients become an embryo transfer. Only one patient was pregnant. The clinical pregnancy rate was 1 of 12 (9%) per embryo transfer. Poor responders undergoing controlled ovarian hyperstimulation with letrozole in cycles with high basal FSH and who are vigorous gonadotrophin stimulation resistant will often show adequate ovarian response and reach oocyte retrieval and ET. The pregnancy rates, however, remain low. This intervention comparing to the cost of gonadotrophin protocols may have future implications for the treatment of poor responders.