Endometriosis and risk factors in pregnancy, labor and delivery: a case-control study.

Background: It is a common thought that endometriosis and its related pain symptoms could improve during pregnancy. However, endometriosis was shown to affect the regular development of pregnancy and delivery outcomes. Several adverse events may occur in the peri-implantation period, and may perpetuate throughout the pregnancy of patients diagnosed with the disease.

Methods: We analyzed pregnancy, delivery and neonatal outcomes in two groups of patients (case and control group), a total of 91 women with endometriosis were 1:3 matched to 273 controls by age. Diagnosis of endometriosis was histologically confirmed and a database with general medical and gynecological history, pregnancy course, delivery mode and newborn conditions was analyzed.

Results: Patients with endometriosis presented higher rates of gestational hypertension (4.4% vs. 0.8%, P=0.02), pre-eclampsia (2.2% vs. 0, P=0.014) and placenta previa (3.3% vs. 0, P=0.003). Caesarean delivery (29.6% vs. 11.3%, P value <0.01) and postpartum hemorrhage (26.5% vs. 11.9%, P=0.04) were more common among patients diagnosed with endometriosis. Multivariate logistic regression showed that cesarean delivery was associated with endometriosis, hypertension and prior cesarean delivery. Postpartum hemorrhage is significantly higher in women treated for endometriosis (26.5% vs. 11.9%, P=0.037).

Conclusions: Endometriosis is related to a higher risk of preeclampsia, placenta previa and postpartum bleeding but it does not increase the risk of cesarean delivery during labor. Obstetricians should consider such associations when managing pregnant patients with a history of endometriosis.