Long-term outcome of fetus with ameliorated cystic hygroma

Objective: Cystic hygroma often ameliorates or disappears with pregnancy progression. Fetuses/neonates with amelioration, when without chromosomal or major structural abnormality, generally show a favorable outcome at birth. The present study was aimed to clarify the short/long-term outcomes of fetuses/neonates with the amelioration of cystic hygroma during pregnancy. Material and methods: This was a retrospective observational study. We focused on fetuses with cystic hygroma managed in our institute between January 2006 and June 2019. The infants were followed by pediatricians (neonatologist, pediatric cardiologist, and pediatric neurologist) and pediatric outcomes were retrieved from the medical records up to 3 years old. Results: One hundred and seven fetuses with cystic hygroma were included. Of the 107, cystic hygromas ameliorated in 31 fetuses (31/107: 29%). Of the 31, there were 26 livebirths. Half (n = 13) of the 26 fetuses had a good outcome, whereas the remaining half (n = 13) had abnormalities. Various abnormalities were detected in their infancies. A nuchal thickness (diameter of hygroma) of ≥5 mm was significantly correlated with abnormalities (P = 0.047). Conclusion: Physicians should pay attention to fetuses/neonates with ameliorated cystic hygroma. Of those, special attention should be paid to fetuses/neonates with a nuchal thickness at diagnosis ≥5 mm