Is oxytocin receptor antagonist administration around embryo transfer associated with IVF treatment success? A systematic review and meta-analysis.

A systematic literature review and meta-analysis was conducted to evaluate whether the administration of an oxytocin receptor antagonist (OTR-a) around embryo transfer is associated with live birth and pregnancy achievement in IVF treatment. Multiple databases were searched for randomized controlled trials (RCT) comparing the outcome of IVF treatment with administration of an OTR-a before, during or after embryo transfer versus administration of placebo/nil. The literature search identified 11 eligible RCT. The active compound was intravenous atosiban (n = 7), subcutaneous barusiban (n = 1) and oral nolasiban (n = 3). Clinical pregnancy rate was significantly higher in women receiving an OTR-a around embryo transfer (relative risk [RR] 1.31, 95% confidence interval [CI] 1.13–1.51, P = 0.0002, I 2 = 61%, n = 11 studies, n = 3611); however, live birth rate was not statistically significantly affected (RR 1.09, 95% CI 0.98–1.20, P = 0.11, I 2 = 25%, n = 5 studies, n = 2765). A sensitivity analysis on low risk of bias studies likewise indicates a higher clinical pregnancy chance (RR 1.11, 95% CI 1.01–1.22, P = 0.03, I 2 = 5%, n = 5 RCT, n = 2765). OTR-a administration in IVF treatment has the potential to increase IVF efficacy, although the treatment effects observed so far are small and have not been sufficiently corroborated. [ABSTRACT FROM AUTHOR]