Objective To provide the basis for genetic counseling of fetus with cystic hygroma, we analyzed the karyotypes and array-CGH outcomes of fetus with cystic hygroma which was diagnosed by ultrasound before 14 weeks. Methods We retrospectively analyzed the karyotypes and array-CGH outcomes of single fetus with cystic hygroma which was diognosed by ultrasound before 14 weeks.All these fetus took chorionic villus for prenatal diagnosis. Results 29 cases of fetus, 21 cases (72%) of fetus had chromosomal abnormalities, including 18 cases of abnormal chromosome aneuploidy, 1 case of ring chromosome, 1 cases of chromosome translocation, 1 cases of chromosome repeat. As to the results of array-CGH，22 cases (76%) were CNVs．Conclusions The chromosome abnormality rate was rather high in the single fetus with cystic hygroma which was diognosed by ultrasound before 14 weeks. Array-CGH was helpful to confirm the specific chromosomal abnormalities and pathogenic gene. Karyotype analysis was still the important way to find the cause of fetus with cystic hygroma.
