Association of Parity and Infant Feeding Method with Breast Density on Mammography

Mammography (MMG) is widely used for the screening and diagnosis of breast cancer. High breast density on MMG prevents breast cancer detection. In the present study, we analyzed the effects of parity and infant feeding method on mammographic breast density. Ninety women diagnosed as having breast cancer were analyzed. Using the results of medical questionnaires, subjects were grouped according to their parity and infant feeding method, into either nulliparity or parity, and formula-feeding or breastfeeding. Each group consisted of 30 consecutive women from 45 to 49 years. Nulliparous group was unaffected by either parity or breastfeeding, formula-feeding group was affected by parity but not breastfeeding, and breastfeeding group was affected by both parity and breastfeeding. Mammographic breast density was evaluated on the contralateral and cancer-free breast, and was classified into ≥ 50% dense as high breast density and