Pituitary block with gonadotrophin-releasing hormone antagonist during intrauterine insemination cycles: a systematic review and meta-analysis of randomised controlled trials.

<bold>Background: </bold>Several randomised controlled trials (RCTs) have investigated the usefulness of pituitary block with gonadotrophin-releasing hormone (GnRH) antagonists during intrauterine insemination (IUI) cycles, with conflicting results.<bold>Objective: </bold>The aim of the present systematic review and meta-analysis of RCTs was to evaluate the effectiveness of GnRH antagonist administration as an intervention to improve the success of IUI cycles.<bold>Search Strategy: </bold>Electronic databases (MEDLINE, Scopus, EMBASE, Sciencedirect) and clinical registers were searched from their inception until October 2017.<bold>Selection Criteria: </bold>Randomised controlled trials of infertile women undergoing one or more IUI stimulated cycles with GnRH antagonists compared with a control group.<bold>Data Collection and Analysis: </bold>The primary outcomes were ongoing pregnancy/live birth rate (OPR/LBR) and clinical pregnancy rate (CPR). Pooled results were expressed as odds ratio (OR) or mean differences with 95% confidence interval (95% CI). Sources of heterogeneity were investigated through sensitivity and subgroups analysis. The body of evidence was rated using GRADE methodology. Publication bias was assessed with funnel plot, Begg's and Egger's tests.<bold>Main Results: </bold>Fifteen RCTs were included (3253 IUI cycles, 2345 participants). No differences in OPR/LBR (OR 1.14, 95% CI 0.82-1.57, P = 0.44) and CPR (OR 1.28, 95% CI 0.97-1.69, P = 0.08) were found. Sensitivity and subgroup analyses did not provide statistical changes in pooled results. The body of evidence was rated as low (GRADE 2/4). No publication bias was detected.<bold>Conclusion: </bold>Pituitary block with GnRH antagonists does not improve OPR/LBR and CPR in women undergoing IUI cycles.<bold>Tweetable Abstract: </bold>Pituitary block with GnRH antagonists does not improve the success of IUI cycles. [ABSTRACT FROM AUTHOR]