O-140 Uterine septum: clinical implications on fertility and obstterics outcomes. A systematic review and meta-analysis

Study question How does the septate uterus and his metroplasty influence pregnancy rate (PR), live birth rate (LBR), spontaneous abortion rates (SA) and preterm labour rates (PL)? Summary answer Uterine septum is associated with a poor reproductive outcome. Metroplasty reduce the rate of SA but non-conclusive evidence can be extrapolated about PR and PL. What is known already Different studies evaluated the correlation between uterine septum and reproductive outcomes. On one hand, studies reported its association with poor obstetrics outcomes. On the other hand, recent studies raised doubts about the effectiveness of septum metroplasty to improve reproductive outcomes, although recent position papers continue to propose metroplasty in patients with a septate uterus and a history of infertility or miscarriages. Debate is still ongoing on reproductive outcomes of uterine septum on infertile patients and especially on patients with recurrent miscarriage, leading to an unanswered question whether or not these women should be treated. Study design, size, duration Systematic review and meta-analysis of published studies that evaluated the clinical impact of uterine septum and its metroplasty on reproductive and obstetrics outcomes. The meta-analysis included study with infertile patients or patients with a history of recurrent miscarriage. Searches were conducted using the following search terms: uterine septum, septate uterus, metroplasty, pregnancy rate, live birth rate, spontaneous miscarriage, infertility, preterm delivery. Primary outcomes were PR and LBR. Secondary outcomes were SA and PL. Participants/materials, setting, methods The meta-analysis was written following the PRISMA guidelines. Fifty-nine full-text articles were preselected based on title and abstract. Endpoints were evaluated in three subgroups: 1) infertile/recurrent miscarriage patients with septum versus no septum 2) infertile/recurrent miscarriage patients with treated versus untreated septum 3) infertile/recurrent miscarriage patients before-after septum removal. Odds-ratios (OR) with 95% confidence intervals (CI) were calculated for outcome measures. Random-effect meta-analysis was performed and a p-value less than 0.05 was considered statistically significant. Main results and the role of chance Data from 37 articles were extracted. In the first subgroup (10 studies), a lower PR and LBR were associated with septate uterus vs. controls, respectively (OR 0.39, 95% CI 0.26 to 0.58; p < 0.000; low-heterogeneity and OR 0.21, 95% CI 0.12 to 0.39; p < 0.0001; small-heterogeneity) and a higher proportion of SA and PL was associated with septate uterus vs. controls, respectively (OR 4.17, 95% CI 2.83 to 6.15; p < 0.000; moderate-heterogeneity and OR 2.18, 95% CI 1.27 to 3.76; p = 0.005; low-heterogeneity). In the second subgroup (8 studies), PR and PL were not different in removed vs. unremoved septum, respectively (OR 1.10, 95% CI 0.49 to 2.49; p = 0.82; moderate heterogeneity and OR 0.44, 95% CI 0.18 to 1.08; p = 0.08;low-heterogeneity) and a lower proportion of SA was associated with removed vs. unremoved septum (OR 0.40, 95% CI 0.17 to 0.95; p = 0.001; substantial-heterogeneity). In the third subgroup (19 studies), the proportion of LBR was higher after the removal of septum (OR 49.58, 95% CI 29.93 to 82.13; p < 0.0001; moderate-heterogeneity) and the proportion of SA and PL was lower after the removal of septum, respectively (OR 0.02, 95% CI 0.02 to 0.04; p < 0.000; moderate-heterogeneity and OR 0.05, 95% CI 0.03 to 0.08; p = <0.000; low-heterogeneity). Limitations, reasons for caution The present meta-analysis is limited by the observational design of included studies because, in literature, there are no prospective randomized controlled trials (RCTs). In the second and third subgroup of analysis clinical heterogeneity within and between studies represents another limitation. Wider implications of the findings The results of this meta-analysis confirm the detrimental effect of uterine septum on PR, LBR, SA and PL. Its treatment seems to reduce the rate of SA. Metroplasty should still be considered as good clinical practice in patients with a history of infertility and recurrent abortion. Trial registration number Not applicable © The Author(s) 2020. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please e-mail: [email protected].