Genetic Implications of Ultrasonographic Detection of In Utero Cystic Hygroma

Sir.—In a recent radiological case of the month (Journal 134:311-312, 1980), a cystic nuchal mass interpreted as a hygroma was detected by ultrasonography in a fetus of 28 weeks' gestation. The full implications of the antenatal detection of hygroma by ultrasonography should be emphasized.

Chromosomal anomalies are probably responsible for a high percentage of spontaneous abortions and fetal deaths.¹ Cystic hygroma of the back of the neck is responsible for the webbed neck seen in stillborn and newborn infants with XO karyotypic Turner's syndrome. The appearance of the stillborn infant illustrated in the aforementioned case is strongly suggestive of that diagnosis.² The cleft lip/palate not associated with hygroma described in the previous stillborn infant also may be seen in Turner's syndrome, but neither those findings nor hygroma are sufficient to make that diagnosis in the absence of other pathologic findings or a karyotype. The posterior hygroma should