Beyond MARS: Magnetic Resonance Study: A Novel Assessment of Placental Perfusion During Pregnancy

The transfer of oxygen and nutrients from the mother to the baby across the placenta is essential to successful pregnancy outcomes. Conversely, poor transfer of oxygen from the mother to the baby through the placenta is associated with adverse outcomes, including poor fetal growth, preterm delivery, and stillbirth. Babies need oxygen to maintain good health. Babies born to women who are obese before pregnancy have a higher risk of experiencing health problems in pregnancy and long-term health problems such as metabolic syndrome, obesity, and diabetes. Obesity has continued to increase in the United States over the past decades, and a quarter of pregnancy complications, such as preterm birth, gestational diabetes, hypertension, and large gestational infants, can be attributed to maternal obesity.

In this study, the investigators propose using a novel method, arterial spin labeling (ASL)) to measure placental blood flow. The study aims to evaluate the feasibility and reliability of assessing placental blood flow by this novel method. The investigators will also evaluate the mean global placental perfusion of second and third trimester placentas among obese women as compared to those with a normal weight before pregnancy. To provide an innovative and comprehensive evaluation of placental oxygen delivery and insights into the delivery of nutrients, investigators will compare global placental perfusion of second and third trimester placentas with measurements of placental oxygenation by R2* relaxation rates.