Perinatal Outcomes of Fetal Intra‐Abdominal Umbilical Vein Varix: A Retrospective Cohort Study

PURPOSE: To investigate the ultrasonographic characteristics and perinatal outcomes of fetuses diagnosed with FIUVV and compare isolated FIUVV cases with low-risk pregnancies. METHODS: This retrospective study was conducted among patients diagnosed with FIUVV at a tertiary referral center between 2020 and 2024, along with a control group of low-risk pregnancies. The gestational age at the diagnosis and birth, the presence of additional structural and/or chromosomal anomalies in the fetus, and neonatal outcomes were recorded. RESULTS: A total of 66 fetuses were included in the study, comprising 26 diagnosed with FIUVV and 40 in the control group. Additional structural abnormalities were identified in 23.1% of FIUVV cases, and chromosomal abnormalities were detected in three nonisolated cases. In the comparison of isolated FIUVV cases with the control group, fetal growth restriction (FGR) and preterm birth were significantly higher in FIUVV cases. CONCLUSION: FIUVV, even when identified as an isolated finding, may be associated with an increased risk of adverse perinatal outcomes. Careful prenatal surveillance for fetal growth, along with screening for additional structural abnormalities, may contribute to more effective clinical management of these cases.