Presence and Size of Placental Lakes on 20-Week Fetal Anatomy Ultrasound and Obstetrical Outcomes.

Our objective was to determine if placental lake presence or size is associated with adverse pregnancy outcomes. This was a retrospective cohort of patients who had fetal anatomy ultrasounds at 18-22 weeks and delivered between 2018 and 2022. Placental lakes were classified as small (>2.0 to 3.9 cm) or large (≥4 cm). Multiple gestations, placenta previas, and placenta accretas were excluded. Outcomes included low birthweight, cesarean delivery, primary cesarean for non-reassuring fetal heart tracing, fetal growth restriction, preterm birth, and severe preeclampsia. A total of 1052 patients were included; 294 had placental lakes (204 small, 90 large). No differences in pregnancy outcomes were observed.