Pregnancy Outcomes and Obstetrical Complications of Twin Pregnancies with Endometriosis: A Single-Center Cohort Study.

Purpose: There are many studies regarding the increased relationship between pregnancy outcomes of singleton with endometriosis. However, there was limited evidence of twin pregnancies with endometriosis. This study aimed to compare the pregnancy outcomes and complications in twin pregnancies with or without endometriosis in a single institution.

Materials and methods: From January 2011 to July 2022, a retrospective analysis of twin pregnancies was conducted. The endometriosis group included patient with histological or visual confirmation before pregnancy or during cesarean section. Pregnancy outcomes and complications were compared between the two groups.

Results: Out of 1714 patients examined, 127 (7.4%) were included in the endometriosis group. Maternal body mass index (BMI) was lower in the endometriosis group (p<0.001). There were no significant differences in maternal age, mode of conception, chorionicity, and pregnancy outcomes, such as gestational age at delivery (p=0.835) and the preterm birth rate (p=0.579). The endometriosis group had a significantly higher rate of obstetrical complication: small for gestational age (SGA) <10% (p=0.029). However, after adjustment for BMI, the endometriosis group showed no statistical significance in obstetrical complications, including SGA (adjusted odds ratio, 1.568; 95% confidence interval, 0.984-2.499; p=0.059).

Conclusion: Twin pregnancies with endometriosis were not related to adverse effects on pregnancy outcomes and obstetrical complications. To confirm these outcomes, further large prospective studies are required.