Fetal megacystis at 11–14 weeks of gestation: 3-year experience of a tertiary center

INTRODUCTION: We aimed to present a comprehensive overview of the underlying etiologies and structural anomalies associated with megacystis and to investigate the history from diagnosis in utero to postnatal outcome.
METHODS: Fetal megacystis was defined in the first trimester as a longitudinal bladder diameter ≥7 mm. For each case, data on and measurements of fetal urinary tract and associated structural anomalies were collected. All available postmortem examinations and postnatal investigations were reviewed to establish the final diagnosis.
RESULTS: A total of 31 cases with fetal megacystis were included in this study. Megacystis was isolated in 24 cases and seven cases were associated with other abnormal ultrasound findings. Spontaneous resolution occurred before birth in 15 cases. Chromosomal abnormality was diagnosed in five cases, including two trisomy 21, one trisomy 18, one trisomy 13, and one Turner syndrome. Vesicoamniotic shunt was performed in three cases after the failure of vesicosentesis procedure.
DISCUSSION AND CONCLUSION: The etiology of fetal megacystis is not known exactly. It is generally a temporary finding in the first trimester, and its continuation in the following weeks is observed with increased chromosomal anomaly and additional anomalies. In fetal megacystis, detailed ultrasonoography and chromosomal analysis should be performed for additional anomalies.