Evaluation of Role of GnRH Antagonist in Intrauterine Insemination (IUI) Cycles with Mild Ovarian Hyperstimulation (MOH): A Prospective Randomised Study

AIMS AND OBJECTIVE: To evaluate the role of GnRH antagonist in prevention of premature LH surge and increasing pregnancy rates in IUI cycle with mild ovarian hyperstimulation (MOH). STUDY DESIGN: Prospective parallel, randomised controlled study. MATERIAL AND METHODS: Couples diagnosed with unexplained, male factor subfertility and with one or both tubes patent were randomised to receive either a GnRH antagonist (study group) or no intervention (control group). All women were treated with clomiphene citrate (D3-D7) followed by HMG. A GnRH antagonist was added when one or more follicles of 16 mm diameter or more were visualised in the study group. When at least one follicle reached a size of ≥18 mm, ovulation was induced by hCG injection. A single IUI was performed 36 h later. The primary outcome was premature LH surge and pregnancy rate. The secondary outcomes were the amount of gonadotropins used, duration of use of GnRH antagonist and incidence and severity of OHSS. RESULTS: A total of seventy patients attending the infertility clinic in the outpatient department of Obstetrics and Gynecology, of a tertiary care centre, were recruited in the study which was carried out from August 2011 to March 2013. The study group included 34 women and 36 in the control arm. The incidence of premature LH surge was significantly lower in the antagonist group as compared to the control group 2.9 vs. 13.9 %, with a p value of <0.001. The clinical pregnancy rates were similar in both the groups 8.8 vs. 11.1 %, p value being 1.000. The amount of gonadotropins used in GnRH antagonist group was lower than in control group but not statistically significant. Duration of GnRH antagonist was 1.85 ± 0.61 days in the study group. CONCLUSION: The delayed administration of GnRH antagonists in MOH with IUI cycles when follicle size is ≥16 mm is beneficial in terms of preventing the occurrence of premature LH surge but with no improvement in pregnancy rates.