Effects of chronic endometritis therapy on in vitro fertilization outcome in women with repeated implantation failure: a systematic review and meta-analysis

To evaluate the impact of antibiotic therapy for chronic endometritis (CE) on IVF outcome.Systematic review and meta-analysis.Not applicable.Infertile women with history of recurrent implantation failure, defined as two or more failed ETs, undergoing one or more IVF cycle(s).The review was registered in PROSPERO (CRD42017062494) before the start of the literature search. Observational studies were identified by searching electronic databases. The following comparators were included: women with CE receiving antibiotics vs. untreated controls; women with cured CE vs. women with persistent CE; and women with cured CE vs. women with normal endometrial histology (negative for CE). The summary measures were reported as odds ratio (OR) with 95% confidence interval (CI).Clinical pregnancy rate (CPR), ongoing pregnancy rate/live birth rate (OPR/LBR), implantation rate (IR), miscarriage rate.A total of 796 patients (from five studies) were included. Women receiving antibiotic therapy (without the histologic confirmation of CE cure) did not show any advantage in comparison with untreated controls (OPR/LBR, CPR, and IR). Patients with cured CE showed higher OPR/LBR (OR 6.81), CPR (OR 4.02), and IR (OR 3.24) in comparison with patients with persistent CE. In vitro fertilization outcome was comparable between women with cured CE and those without CE (OPR/LBR, CPR, and IR). Miscarriage rate was not significantly different between groups.Chronic endometritis therapy may improve IVF outcome in patients suffering from recurrent implantation failure. A control biopsy should always confirm CE resolution before proceeding with IVF.