A family with 3 cases of pulmonary stenosis with underdeveloped or normal right ventricle is described. In the family there have also been some spontaneous abortions and many infant deaths, and it seems possible that these were also related to congenital cardiac abnormalities. Recognized syndromes with pulmonary stenosis and reports on familial occurrence of this malformation are reviewed. The cases reported in this paper differ from these previously described syndromes. The possibility of sex-influenced monogenic inheritance is discussed.