Fetal Megacystis: Associated Structural Abnormalities and Obstetric Outcomes

Purpose: We evaluated the obstetrical outcomes, ultrasonographic characteristics, and final diagnosis in pregnancies with fetal megacystis (FM). Methods: We evaluated the obstetrical outcomes and associated structural abnormalities of fetuses with FM detected between FM between 2000 and 2021. Results: 17 FM were diagnosed, 16 had follow up. 16 were early megacystis. 14/16 (87.5%) of pregnancies were terminated, 1/16 (6.25%) resulted in intrauterine death, and 1/16 (6.25%) survived. FM was associated with 13 other abnormal sonographic findings in 12/16 (75%) pregnancies. The most common associated ultrasound abnormality was umbilical cord cyst in 3/16 (18.75%). Recognized etiologies included posterior urethral valves (2), trisomy 18 (2), trisomy 13 (1), Prune Belly syndrome (1), and Megacystis-Microcolon-Hypoperistalsis syndrome (1). Conclusion: Most FM are detected in the 2nd trimester, most are electively terminated, are associated with other ultrasonic abnormalities in 75%, most commonly umbilical cord cyst, and have an identifiable cause in 44%.