Fetal pleural effusion 2022-01-22T07:37:48Z With the ongoing evolution and more widespread use of obstetric ultrasound, fetal pleural effusions are being recognized more often and at earlier gestational ages. Fetal pleural effusion is the accumulation of excess fluid in the layers of tissue (pleura) lining the lungs and wall of the chest. It may be primary, also termed hydrothorax, occurring as an isolated finding or it may be secondary, most commonly resulting from non-immune hydrops. Abnormal fetal pulmonary morphology