GnRH antagonist administration to postpone a weekend intrauterine insemination: a large cohort study from a public center

BACKGROUND In Spanish public hospital Reproduction Units it is very problematic to perform programmed intrauterine insemination (IUI) on weekends, if indicated. Small previous pilot studies suggest that using a GnRH antagonist to avoid an LH weekend surge would allow to perform IUI on the following Monday, not impairing the expected pregnancy rate. METHODS Between 1st January 2007 and 31st December 2015, 4.782 intrauterine inseminations were performed at Valladolid University Clinic, Spain, corresponding to 1.650 women. Of them, 911, corresponding to 695 women, should ideally have been performed during the weekend. If it happened that a member of the Reproduction Unit was on duty during that particular weekend, the standard protocol was not interrupted, and the IUI performed as planned (control group, 685 IUIs). If the former was not the case, the weekend gap was bridged by administering 0.25 mg GnRH antagonist (GnRHa). Ovulation was induced by means of 250 ug recombinant HCG (rHCG) 36 h prior to IUI on the following Monday (study group, 226 IUIs). RESULTS There were no differences in the clinical pregnancy rate (13.7 cc vs. 16.2 %, p = 0.371) or in the ongoing pregnancy rate between groups (11.9 % vs. 14.9 %, p = 0.271). The multiple pregnancy rate was also comparable in both groups (14.7 % vs. 18.5 %, p = 0.77). CONCLUSIONS Women with a planned IUI which cannot be performed at the ideal date can be offered postponement for two days with the support of GnRHa treatment, with results that are not inferior to those expected applying the regular protocol.