Fetal alcohol syndrome in dizygotic twins.

A pair of fraternal twins with stigmata of the fetal alcohol syndrome are described. Apparently differences in susceptibility to the dysmorphogenic influence of ethanol caused one twin to be more severely affected than the other one. Both infants are growing poorly postnatally, and both are at risk for retarded development. Any evidence of the fetal alcohol syndrome, however, subtle, should be considered a warning of possible future developmental delay.