Inbreeding effects on fetal growth in Beirut, Lebanon.

Effects of consanguineous marriages on offspring's gestational age and anthropometrics at birth were investigated in Beirut through a hospital-based survey of 1,252 newborns. Twenty-five percent of all newborns were inbred, and the mean inbreeding coefficient was 1.25%. Neither prematurity rate nor weight, length, head circumference, and chest circumference (considered individually, or as a whole) showed a significant pattern by type of parental consanguinity. Failure to demonstrate significant inbreeding effects is reported in several other studies and generally interpreted as the long-term result of continued inbreeding practices.