Male influences on cervical cancer risk.

Risk factors for squamous cell carcinoma of the uterine cervix were studied among low income, married Hispanic women and their husbands, using a case-control design. A total of 45 eligible cases were identified at public hospitals and community clinics in the San Francisco Bay Area. For each case, a control was selected within two years of age from among Hispanic women seen at the same institution. Thirty-nine matched pairs of couples were interviewed to assess histories of sexual behavior and other possible risk factors. Cases and controls differed markedly in the number of past sexual partners of their husbands. Cases were 5.3 times more likely to be married to husbands who had had 20 or more sexual partners than were controls. Cases and controls themselves did not differ in their number of sexual partners, but cases were younger at first intercourse than were controls. The association with husband's sexual history persisted after adjusting for the woman's number of sexual partners or age at first intercourse. These results support the infectious and venereal transmission of cervical cancer and indicate the important role of husbands in its occurrence in a population with high incidence rates.