An MRI approach to assess placental function in healthy humans and sheep

Key points Human placental function is evaluated using non‐invasive Doppler ultrasound of umbilical and uterine artery pulsatility indices as measures resistance in vascular beds, while measurement oxygen consumption ( ) only possible during Caesarean delivery. This study shows the feasibility magnetic resonance imaging (MRI) utero to measure blood flow content vessels calculate delivery by gravid uterus, uteroplacenta fetus. Normal late gestational human uteroplacental MRI was ∼4 ml min −1 kg fetal weight, which similar our measurements sheep those previously measured invasive techniques. Our approach can quantify , involves quantification maternal‐ fetal‐placental flows, gradient between uterine‐ umbilical‐venous blood, providing a comprehensive assessment with clinical potential. Abstract It has not been feasible perform routine vitro studies do reflect true metabolism . Here we propose an method non‐invasively healthy humans sheep. Women n = 20) Merino 10; 23 sets measurements) singleton pregnancies underwent gestation (36 ± 2 weeks 128 9 days, respectively; mean SD). Blood (phase‐contrast) (T1 T2 relaxometry) were major umbilical‐placental vessels, allowing calculation Maternal (ml fetus) uterus (human 54 15, 53 21, P 0.854), 25 4, 22 5, 0.049) slightly lower Uteroplacental fetus; uteroplacental: 4.1 1.5, 3.5 1.9, 0.281; fetus: 6.8 1.3, 7.2 1.7, 0.426) species. Late uteroplacental:fetal ratio did change age (human, 0.256; sheep, 0.121). decreased advancing 0.008), preserved through increase extraction 0.046). By contrast, stable ; 0.443) 0.582). derived keeping prior data obtained Taken together, these confirm reliability approach, offers novel ‘placental test’.