Independent association between uterine malformations and cervical insufficiency: a retrospective population-based cohort study.

OBJECTIVE

The purpose of our study was to explore maternal and fetal outcomes in the second and third trimester in women with uterine malformations.

STUDY DESIGN

This was a retrospective population-based cohort study including women with a diagnosis of uterine malformation arised from workup for infertility or recurrent pregnancy loss, was accidental during pregnancy, or was noticed at the time of cesarean delivery.

RESULTS

A total of 280,721 pregnancies met the inclusion criteria and were divided into two study groups: (1) pregnancies in women with uterine malformations (n = 1099); and (2) controls (n = 279,662). The rate of women presenting uterine malformations was 0.39%. The prevalence of cervical os insufficiency was significantly higher in women with a uterine malformation than in the control group (3.6 vs. 0.4%, p < 0.001). A multivariate analysis, performed to evaluate risk factors for cervical insufficiency in women with uterine malformations. Mullerian anomalies (OR 6.19, 95% CI 4.41-8.70, p < 0.001), maternal age (OR 1.05, 95% CI 1.04-1.06, p < 0.001), recurrent abortions (OR 12.93, 95% CI 11.43-14.62, p < 0.001), and ethnicity (OR 2.86, 95% CI 2.454-3.34, p < 0.001) were found to be independently associated with the development of cervical insufficiency.

CONCLUSION

Uterine anomalies have a strong association with cervical insufficiency. Women with uterine anomalies have an increased risk to develop pregnancy complications that arise from a loss in cervical function during the midtrimester or early third trimester.