Prediction of pulmonary hypoplasia in preterm prelabour rupture of membranes prior to 24+0 weeks of gestation using fetal MRI

INTRODUCTION: Preterm prelabour rupture of membranes (PPROM) prior to 24 weeks of gestation is a rare complication that can lead to pulmonary hypoplasia (PH). This study aimed to assess the predictive value of fetal MRI for PH in this context. METHODS: We conducted a retrospective observational study at Rouen University Hospital (2012-2020). Inclusion criteria were women with PPROM prior to 24 weeks of gestation who underwent fetal MRI and delivered a live neonate. Fetal lung volume (FLV) and lung-to-liver signal intensity ratio (LLSIR) were measured on MRI and compared between neonates with and without PH. Receiver operating characteristic (ROC) curves were calculated to evaluate the performance of the FLV measurement and LLSIR on the prediction of PH. RESULTS: Among 23 fetuses included, 6 had PH. Earlier PPROM, earlier delivery, and severe oligohydramnios were significantly associated with PH. A FLV <51 % of the expected value predicted PH with a sensitivity of 87.5 % and specificity of 100 %. A LLSIR below 1.64 predicted PH with a sensitivity of 100 % and specificity of 83.3 %. CONCLUSION: Fetal MRI using FLV and LLSIR provides valuable prognostic information for predicting PH in cases of PPROM prior to 24 weeks. These markers may support prenatal counselling and perinatal management.