Gestational age adjusted Fetal Lung volumes, are they uniform worldwide

Introduction: To measure normal fetal lung volumes for each GA using MRI normal database.MM: This retrospective study was approved by university ethics committee. Out of 821 fetal MRI’s that were done during 2017-2018 in our institution. Retrospective evaluation revealed 180 fetuses with post-delivery confirmation of normal lung, no additional anomaly and image quality adequate for lung volume measurement. Regression analysis was done for association of fetal lung volumes with gestational age. Gestational age was determined by early pregnancy ultrasound and when not available by LMP.Results: There was a positive correlation between fetal lung volumes and gestational age (p=0.00). While the lung volumes correlated roughly with both Rypens and Meyers formula prior to 20 weeks gestation (p=0.04), no such correlation was found over 20 weeks GA.Over this GA fetal lung volumes in our population had a more consistent correlation with Osada data which represented Japanese fetuses.Conclusion: A single universal formula might not be suitable for fetuses worldwide. Regions and countries might need to establish their own normal range data. In our region data might be more consistent with Asian normal values