Local endometrial injury and IVF outcome: a systematic review and meta-analysis

A systematic review was conducted of the influence of local endometrial injury (LEI) on the outcome of the subsequent IVF cycle. MEDLINE, EMBASE, the Cochrane Library, National Research Register, ISI Conference Proceedings, ISRCTN Register and Meta-register were searched for randomized controlled trials to October 2011. The review included all trials comparing the outcome of IVF treatment in patients who had LEI in the cycle preceding their IVF treatment with controls in which endometrial injury was not performed. The main outcome measures were clinical pregnancy and live birth rates. In total, 901 participants were included in two randomized (n=193) and six non-randomized controlled studies (n=708). The quality of the studies was variable. Meta-analysis showed that clinical pregnancy rate was significantly improved after LEI in both the randomized (relative risk, RR, 2.63, 95% CI 1.39-4.96, P=0.003) and non-randomized studies (RR 1.95, 95% CI 1.61-2.35, P<0.00001). The improvement did not reach statistical significance in the one randomized study which reported the live birth rate (RR 2.29, 95% CI 0.86-6.11). Robust randomized trials comparing a standardized protocol of LEI before IVF treatment with no intervention in a well-defined patient population are needed.