Association of neural tube defects with omphalocele in chromosomally normal fetuses.

Omphalocele is frequently associated with other congenital malformations or a chromosome abnormality. Previously published series of omphalocele have emphasized the association of congenital heart defects or chromosomal abnormalities. We present five cases of omphalocele with concurrent neural tube defect from among the 15 cases of omphalocele evaluated between 1981 and 1985. Fourteen of 15 were detected prenatally. A sixth case is presented in which both a neural tube defect and an omphalocele were suspected on a prenatal ultrasound, but only the latter was found on autopsy. We recommend that a systematic evaluation be performed on every fetus with an omphalocele to include amniotic fluid alpha fetoprotein, acetylcholinesterase levels, chromosome study, and careful ultrasonography looking for evidence of other abnormalities, especially neural tube defects, before counseling the parents.