Abstract
Mammary carcinoma is, generally speaking, more frequent among single women than among women ever married. However, various reports show a slight, although not statistically significant preponderance for married women in younger age groups, while women after the menopause have markedly higher rates. This has been found to apply to morbidity data for Denmark (Clemmesen 1965, 1969, 1974) and South Wales (Lowe & MacMahon 1970) and to mortality data from Amsterdam (Deel-man 1920), Australia (Dorn 1943), New York City (Duffield & Jacobson 1945), and England (Logan 1953).