Ovarian cancer

Impact of breastfeeding on incidence of cancers Further evidence of the positive impact of breastfeeding on the incidence of pre-menopausal breast cancer and epithelial ovarian cancer 

Breastfeeding & ovarian cancer, Rosenblatt 1993 This multinational study showed a 20-25% decrease in the risk of ovarian cancer among women who lactated for at least 2 months per pregnancy, compared to those who had not. 

Breastfeeding & ovarian cancer, Gwinn 1990 This study quantified the effects of cumulative months of pregnancy, breast feeding, and oral contraceptive use on the risk of developing epithelial ovarian cancer in a multicenter, population-based, case-control study. 

Breastfeeding & ovarian cancer, Tung 2003 Data from a case-control study in ovarian cancer risk conducted in Hawaii and Los Angeles between 1993 and 1999 suggests that duration of breastfeeding is significantly and inversely related to nonmucinous tumors.