Amniotic band disruption syndrome associated with elevated amniotic AFP and normal acetylcholinesterase gel test.

Ultrasonography in an 18 week pregnancy selected for detailed scanning because of a single elevated maternal serum AFP result suggested the presence of anencephaly. Amniocentesis at 19 weeks yielded a clear AF with an elevated AFP result (5.4 MOM) and no evidence of an acetylcholinesterase band of neural origin on PAG electrophoresis. At termination, the fetus had cephalo-amniotic fusion and multiple abnormalities including bilateral cleft lip and palate and digital amputations characteristic of the amniotic band syndrome. The cranial defect was completely sealed by attachment of the amniotic surface of the placenta to the skull.