Reproduction in hemophilia.

Patterns of marriage and parenthood were studied in the families of 250 patients with severe hemophilia. The incidence of marriage among adult hemophiliacs was 82.5 percent that of age-matched males of the general United States population, as of 1968. Married hemophiliacs 30 years old or older had an average of 2.1 children each, as of 1971. In the periods 1950-1954 and 1960-1964, the numbers of children sired by hemophiliacs were 25 and 38 percent, respectively, of the numbers expected of age-matched men of the general United States population. This indicates a lesser ability or willingness to have children. The number of additional births to women who were already mothers of hemophiliacs was compared with that expected for women of the general population of the United States, matched for age and parity. In the years 1940 through 1954, the birthrates for the two groups were similar. However, in the years 1955-1968, the birthrate among carriers declined more rapidly than that in the general population. The improved medical treatment of hemophilia has apparently not resulted in a greater willingness of affected persons to transmit the defective gene.