Women who Have Undergone a Tubal Sterilization have a Reduced Risk of Contracting Ovarian Cancer

US researchers followed a cohort of 77544 married female registered nurses 30-55 years old from 1976 to 1988 to determine biological risk factors of ovarian cancer. They found 260 cases of confirmed ovarian cancer. Women who had undergone tubal sterilization were at a significantly lower risk of developing ovarian cancer than those who had not (relative risk [RR] = 0.29). It even had a protective effect when the researchers controlled for age weight parity duration of oral contraceptive (OC) use smoking age at menarche age at menopause and hysterectomy status. When they compared women who had undergone tubal sterilization with women who used other contraceptives tubal sterilization still had a significantly reduced risk of ovarian cancer (RR = 0.3). The same investigators compared 11017 women who had had a hysterectomy with 96851 premenopausal and postmenopausal women who had not had a hysterectomy to examine the effect of hysterectomy on ovarian cancer. Women who had undergone a hysterectomy were significantly less likely to develop ovarian cancer than those who had not undergone hysterectomy (RR = 0.66). A significant inverse association between women who had had the hysterectomy 5-9 years before and ovarian cancer existed while women who had undergone a hysterectomy at least 15 years before had a nonsignificant decrease in risk of developing ovarian cancer indicating that the screening of ovaries for malignancy prior to hysterectomy did not introduce detection bias into hysterectomys effect on ovarian cancer development. These findings show that tubal sterilization and hysterectomy have a protective effect against ovarian cancer but more research is needed to identify biological mechanisms.