Women affected by endometriosis have an independently elevated risk of placenta previa in pregnancy, a recent study found. The retrospective cohort study included women who delivered a singleton live birth from 2003 to 2013 in a tertiary level academic center. The main outcome measures were gestational hypertension, preeclampsia, placenta previa, placental abruption, postpartum hemorrhage, preterm birth, low birth weight, small for gestational age, and neonatal intensive care unit admission. Among 52,202 eligible mother-infant pairs, 469 mothers with surgically diagnosed endometriosis from a previous hospital encounter were identified. Researchers found:

• Women with endometriosis were on average older and more likely to be primiparous, have lower gravidity, have a history spontaneous abortion, conceive with assisted reproductive technology, and reside in areas with higher income.
• They were also found to have an elevated risk of placenta previa (relative risk [RR], 3.30) and cesarean delivery (RR, 1.24).
• After adjustment for potential confounding factors, women with endometriosis has a significantly elevated risk of placenta previa vs women without endometriosis (adjusted RR, 2.54).