Genetic causes of hydrops fetalis.

A series of 1790 fetal and neonatal autopsies performed between 1976 and 1988 were retrospectively investigated for the presence of hydrops. Thirty (5.5%) and 35 (2.8%) cases of hydrops were found in the groups of fetal and neonatal autopsies, respectively. Genetic causes accounted for 35%. A careful search for previously reported genetic causes of fetal hydrops indicated 64 different etiologies. Twenty-one of them were not mentioned in the previous reviews: these include 9 skeletal dysplasias, 5 inborn errors of metabolism, 3 autosomal recessive, 3 autosomal dominant conditions, and 1 chromosomal abnormality.