Amniotic band syndrome and conditions simulating disruption malformations.

Twelve cases of fetal malformation due to the amniotic band syndrome (ABS) or disruption sequence were reviewed; these included craniofacial malformations, limb defects and gastroschisis. No one case was similar to another. The initial diagnosis was correct in 5 of the 12 cases, mainly those involving limb defects. All 4 cases in which major malformations were present were initially diagnosed incorrectly. The importance of correct diagnosis mainly concerns counselling regarding the future risk of recurrence--the probability of familial recurrence of ABS is very low, whereas the risk of recurrence of a familial neural tube defect is about 5%.