Effect of GnRH antagonists on clinical pregnancy rates in ovulation induction protocols with gonadotropins and intrauterine insemination.

Introduction: Intrauterine insemination (IUI) after controlled ovarian hyperstimulation (COH) was applied to selected infertile patients to determine the effect of gonadotropin-releasing hormone (GnRH) antagonists in IUI cycles, in which recombinant follicle-stimulating hormone (rFSH) had been used for COH.

Methods: This study was conducted between April 1, 2009 and June 10, 2009, and involved a total of 108 patients. These patients had primary or secondary infertility, which resulted in an indication for IUI, and they each received two cycles of ovarian stimulation treatment with clomiphene citrate. The patients were randomised into two groups--patients in group A received rFSH + GnRH antagonist (n = 45), while those in group B received only rFSH (n = 63).

Results: The mean age of the patients was 31.84 ± 3.73 years and the mean body mass index (BMI) was 24.40 ± 1.88 kg/m(2). The mean age and BMI of the patients in groups A and B were not significantly different. There was no significant difference in the mean total rFSH dose administered (988.33 IU in group A and 871.83 IU in group B). When compared to group B, the mean number of follicles that were > 16 mm on the human chorionic gonadotropin (HCG) trigger day was significantly higher in group A (1.58 and 1.86, respectively; p < 0.05). When the two groups were compared, there were no statistically significant differences in the number of cancelled cycles due to premature luteinisation (none in group A vs. two in group B) and the rate of clinical pregnancy (8.9% in group A vs. 7.9% in group B).

Conclusion: No significant improvement in the clinical pregnancy rates was observed when GnRH antagonists were used in COH + IUI cycles, despite the significant increase in the number of follicles that were > 16 mm on HCG trigger day.