Impact of congenital uterine anomalies on obstetric and perinatal outcomes: systematic review and meta-analysis

Abstract

Background: Congenital uterine anomalies (CUA) can be associated with impairments of early and late pregnancy events.

Objective: To assess the impact of CUA on reproductive outcomes in pregnancies conceived spontaneously or after assisted reproduction.

Materials and methods: Systematic review and meta-analysis of cohort studies comparing patients with CUA versus women with normal uterus. A structured literature search was performed in leading scientific databases to identify prospective and retrospective studies. The Newcastle-Ottawa scale, adapted to AHRQ standards, was used to assess the risk of bias. Pooled odds ratios (OR) were calculated. Publication bias and statistical heterogeneity were assessed, and meta-regression was used to analyse the heterogeneity.

Main outcome measures: Miscarriage, ectopic pregnancy, placental abruption, term, and premature rupture of membranes (PROM), malpresentation at delivery, preterm delivery prior to 37, 34 and 32 weeks, caesarean delivery, intrauterine growth restriction/small for gestational age, foetal mortality and perinatal mortality.

Results: 32 studies were included. CUAs increased significantly the risk of first/second trimester miscarriage (OR:1.54;95%CI:1.14-2.07), placental abruption (OR:5.04;3.60-7.04), PROM (OR:1.71;1.34-2.18), foetal malpresentation at delivery (OR:21.04;10.95-40.44), preterm birth (adjusted OR:4.34;3.59-5.21), a caesarean delivery (adjusted OR:7.69;4.17-14.29), intrauterine growth restriction/small for gestational age (adjusted OR:50;6.11-424), foetal mortality (OR:2.07;1.56-2.73) and perinatal mortality (OR:3.28;2.01-5.36).

Conclusions: CUA increases the risk of complications during pregnancy, delivery, and postpartum. Complications most frequent in CUA patients were preterm delivery, foetal malpresentation, and caesarean delivery.

What is new?: Bicornuate uterus was associated with the highest number of adverse outcomes, followed by didelphys, subseptate and septate uterus.

Figure 1

PRISMA flowchart diagram.

Figure 2

Forest plots of individual and pooled effects of CUA (combined) on first (A), second trimester (B) and any trimester (C) miscarriage risk.

Figure 3

Forest plots of individual and pooled effects on first trimester miscarriage by type of CUA.

Figure 4

Forest plots of individual and pooled effects on second trimester miscarriage by type of CUA.

Figure 5

Forest plots of individual and pooled effects on any trimester miscarriage by type of CUA.