The concept of ovarian cancer as a consequence of hypergonadotropic hypogonadism implies that risk factors for early menopause may also be risk factors for ovarian cancer. Gonadal radiation and the oophoritis of mumps are possible examples of environmental risk factors for early menopause and ovarian cancer. Family history is a strong determinant for both early menopause and ovarian cancer, implicating genetic factors in these disorders. Case-control data suggest that galactose consumption through the ingestion of high-lactose dairy foods may be a dietary risk factor and that galactose metabolism, as measured by galactose-1-phosphate uridyl transferase, may be a genetic risk factor for early menopause and ovarian cancer. Supporting evidence includes animal studies, case reports, and ecologic studies. Avoidance of a high-galactose diet may decrease the risk for early menopause and ovarian cancer. Alternatively, hormonal agents that lower gonadotropins may block ovarian cancer as a consequence of oocyte toxins, even if they do not prevent the early menopause.