To investigate the prenatal diagnostic value of chromosome microarray analysis (CMA) in fetuses with isolated or non-isolated umbilical cord cysts (UCCs) of various locations and numbers.
Between November 2015 and November 2021, 45 pregnant women carrying fetuses with UCCs underwent amniocentesis and CMA. Fetal prognoses were followed from 6 months to 5 years.
Five cases (11.1%, 5/45) of chromosomal aberrations were detected. No significant difference in total chromosome abnormalities was found between fetuses with isolated and non-isolated UCCs (13.3% [2/15] vs 10% [3/30];  > .999). No common autosomal aneuploidies were found in fetuses with isolated UCCs. At follow-up, among 45 fetuses, there were 11 (24.4%) pregnancy terminations, 26 (57.8%) live healthy births, 4 (8.9%) postnatal UCC-related surgeries, and 4 (8.9%) live births of fetuses with other diseases. The frequency of postnatal surgeries of the infants with UCCs located adjacent to the anterior abdominal wall was higher than those located adjacent to the fetal surface of the placenta (30.8% [4/13] vs 0% [0/22];  = .014). All 26 live healthy neonates and 4 neonates that underwent postnatal surgery had an overall good prognosis.
For fetuses with isolated or non-isolated UCC, CMA could be a choice for parents after providing detailed information. Even when surgery was required, pregnancy outcomes and short- and long-term prognoses for fetuses with UCCs were favorable.