Characteristics and outcome of fetal cystic hygroma diagnosed in the first trimester.

OBJECTIVE

The aim of this study was to determine the course of pregnancy and the neonatal outcome of fetuses with cystic hygroma diagnosed at 10-14 weeks' gestation.

METHODS

Maternal and fetal data (nuchal translucency, karyotype, pregnancy outcome) in cases of fetal cystic hygroma, admitted or referred to our antenatal diagnostic centre, were prospectively entered into a computer database. Paediatric outcome was analysed when relevant.

RESULTS

Some 72 fetuses had cystic hygroma. The mean size of the cystic hygroma was 7.9 mm. Chromosomal abnormalities were present in 52.7% of cases (38/72), including 14 cases (36.8%) of Down syndrome. A total of 34 chromosomally normal pregnancies gave rise to 18 live births (52.9%), with no visible serious structural abnormalities. The outcome of pregnancy was unfavourable (miscarriage, elective termination, serious structural abnormalities) in 77.7% of cases (56/72). The 18 live-born infants were followed up for 17-98 months. Sixteen infants developed normally, while 1 developed Noonan's syndrome and 1 had a urinary tract abnormality (pyelo-ureteral junction; PUJ).

CONCLUSION

These data suggest that the prognosis of fetal cystic hygroma detected during the first trimester is poor, and show that sonographic evaluation of fetal nuchal translucency thickness in the first trimester is crucial.