Mechanisms of Pregnancy Vascular Adaptations

Inclusion Criteria: * Female * Ages 18 to 40 years old * Singleton gestation between 28 weeks, 0 days and 41 weeks, 0 days gestational age at the time of consent * Undergoing caesarean section, either planned or otherwise with or without trial of labor Exclusion Criteria: * Treatment of severe hypertension by antihypertensive or use of magnesium sulfate after the patient is hospitalized for the diagnosis of preeclampsia. * Any major fetal structural anomalies or aneuploidies * Undergoing cesarean section for placental abruption or bleeding complications. * Singleton gestation not within 36 weeks, 0 days and 41 weeks, 0 days gestational age at the time of enrollment (delivery)