Umbilical cord pseudocyst in a fetus with trisomy 18.

An umbilical cord pseudocyst was detected in the 28th week of gestation in a fetus complicated with growth restriction and polyhydramnios. The combination of cord pseudocysts, growth restriction, and polyhydramnios prompted us to perform a detailed ultrasonographic examination (gray scale and three-dimensional), which revealed the presence of micrognathia, overlapping fingers, and congenital heart defects, features characteristic of trisomy 18. Karyotyping confirmed a diagnosis of trisomy 18. After spontaneous labor onset, the infant was delivered at 31 weeks of gestation, and died soon after delivery. An umbilical cord pseudocyst is a good marker for the prenatal detection of trisomy 18. Copyright 2003 S. Karger AG, Basel