381: Karyotype and outcome of fetuses with cystic hygroma diagnosed in the first trimester


      The aim of this study was to determine the karyotyping results and course of pregnancy of fetuses with cystic hygroma (CH) diagnosed at routine first trimester ultrasound examination.

      Study Design

      A computerized ultrasonography database identified fetuses with CH at 11+013+6 weeks of gestation from January 2005 through December 2008 in Cheil General Hospital. Among them, only cases with known pregnancy outcome were included in this study. We reviewed the medical records of these pregnant women and infants. Spontaneous abortion, intrauterine fetal death, abnormal karyotypes or finding of one or more major structural defects were assigned as an adverse fetal outcome.


      During the study period, total 24, 565 fetuses underwent routine 1st trimester ultrasonographic examination for NT measurement in our institute. Among them, 57 fetuses (0.23%) were diagnosed with CH. Excluding 7 cases of follow-up loss, 50 fetuses were included study population. Forty-two fetuses were undergone karyotyping study. Chromosomal abnormalities were present in 30.9% of cases (13/42) of these: 4 cases of 45, XO, 4 cases of trisomy 18, 4 cases of trisomy 21, and 1 case of trisomy 13. Among fetuses with normal karyotype (n= 29), intrauterine fetal death occurred in two fetuses before 20 weeks of gestation. Major structural fetal malformations detected in 20-weeks level II sonogram were diagnosed in 11 of the remaining 27 cases (40.7%). A total of 29 chromosomally normal pregnancies gave rise to 16 live births (55.2%), with no structural abnormalities.


      These data suggest that the prognosis of fetus with CH diagnosed in the first trimester is poor. Therefore, fetuses with CH requires more careful assessment of the fetus, with regard to both karyotyping and follow-up level II scan for detecting structural anomaly.