Effectiveness of gonadotrophin-releasing hormone agonist therapy to improve the outcomes of intrauterine insemination in patients suffering from stage I-II endometriosis

To explore the role of postoperative gonadotrophin releasing hormone agonist (GnRH-a) therapy before treatment with intrauterine insemination (IUI) for infertile females with stage I-II endometriosis. Ninety-seven patients diagnosed with stage I-II endometriosis before IUI were enrolled in this study. The clinical pregnancy rate, cumulative pregnancy rate, live birth rate and newborn conditions were compared between the two groups with and without GnRH-a therapy. The clinical pregnancy rate of IUI in the GnRH-a group was higher than that in the control group (15.29% vs. 11.82%, p = .035). By logistic regression analysis, patients treated with GnRH-a had a higher clinical pregnancy rate than those without (adjusted odds ratio (AOR) 23.190, 95% confidence interval (CI) 1.238-434.312). The live birth rate per IUI cycle in the GnRH-a group was also higher than in the controls (12.94% vs. 10%). However, the difference was not statistically significant (p = .311, AOR 4.844, 95% CI 0.229-102.320). The patients with GnRH-a therapy had a similar incidence of multiple pregnancy rate (0% vs. 0%), miscarriage rate (2.35% vs. 0.91%) and ectopic pregnancy rate (0% vs. 0.91%) as compared to the control group. The cumulative pregnancy rates were all higher in patients administered with GnRH-a than those without GnRH-a treatment in different cycles (one cycle: 17.07% vs 12.50%; two cycles: 29.27% vs 19.64%; three cycles: 31.71% vs 23.21%; ≥four cycles: 31.71% vs 23.21%), but the difference was not statistically significant. Notably, there was no more pregnancy after the third IUI cycle. The gestation weeks of delivery in the two groups were 39.09 ± 1.04 and 38.60 ± 1.17, respectively (p = .323). Nor was there difference in birth weight between the two groups (3236 ± 537 g vs 3435 ± 418 g, p = .360). The administration of GnRH-a in patients with stage I-II endometriosis could be beneficial to the outcomes of IUI. It is recommended that IUI should be discontinued after three failed attempts. KEY MESSAGES Endometriosis is a common cause of infertility, but the exact mechanism remains unclear. The administration of GnRH-a before IUI treatment is beneficial for patients suffering from stage I-II endometriosis. After three failed attempts, IUI should be stopped in patients with stage I-II endometriosis.