Abstract： Objective:To analyze the correlation of fetal cervical cystic hygroma (CCH) with chromosomal and structural abnormalities and to assess the prognosis of CCH.Methods:This study retrospectively enrolled 70 fetuses with CCH diagnosed by prenatal ultrasound in the First Affiliated Hospital of Xi'an Jiao Tong University from July 2015, to December 2021. According to whether complicated by structural malformations or other anomalies, all the subjects were divided into the non-isolated and isolated CCH groups. The correlation of CCH and the gestational age at detection with chromosomal and structural abnormalities were analyzed and the prognosis of the cases were summarized using Chi-square test. Results:There were 34 isolated CCH (34/70, 49%) and 36 non-isolated CCH (36/70, 51%) among the 70 cases. In the non-isolated CCH group, there were eight cases (22%, 8/36) with abnormal heart structure, ten (28%, 10/36) with abnormal anterior abdominal wall, 16 (44%,16/36) with systemic edema and/or pleural effusion, one (3%,1/36) with craniocerebral abnormalities and one with holoprosencephaly and cardiac structural abnormalities. Eighteen out of 44 cases undergoing chromosome testing had chromosomal abnormalities, which were trisomy-18 ( n=6), trisomy-21 ( n=3), trisomy-13 ( n=3), 45,XO ( n=3), and chromosome segment duplication or deletion ( n=3). The detection rate of chromosome abnormality was higher in non-isolated CCH group comparing with isolated CCH group [59%(13/22) vs 23%(5/22), χ2=6.02, P=0.014]. There was no significant difference in the gestational age at the detection of CCH or proportion of women of advanced maternal age between the isolated and non-isolated CCH groups (both P>0.05). The ratios of isolated CCH cases with normal chromosome detected at the gestational weeks of 14-27 +6 was higher than those detected at 11-13 +6 weeks [62%(13/21) vs 17%(4/23), χ2=7.39, P=0.001]. Out of the 17 cases with isolated CCH and normal chromosomes, 12 were live births. One of the 12 cases still had a cystic mass with a diameter of 3 cm in the neck nine months after birth, and the other 11 cases had no mass at birth but one case died at the age of five months (hospitalized one week for neonatal edema),one case was found with anal atresia three days after birth and underwent operation and the remaining nine cases were normal during five months to six years follow-up. Conclusions:Non-isolated CCH is at a higher risk of chromosomal abnormalities. Isolated CCH cases detected later had higher rate of normal chromosome and often have a higher survival rate.