SOCIOECONOMIC-STATUS, LACTATION AND BREAST-CANCER RISK OF PAROUS WOMEN IN TAIWAN

The objective of this study was to evaluate effects of socioeconomic s tatus and lactation on breast cancer of parous women in Taiwan. A tota l of 102 parous incident cases of female breast cancer in Taipei City were recruited from National Cancer Registry. Another 102 community pa rous controls individually matched with each case on residential area and age (within five years) were randomly selected from household regi stration profiles. Socioeconomic status including ethnic group, school ing years, family income, and religion, reproductive risk factors, lac tation and body size risk factors for breast cancer were collected fro m a structured questionnaire interview. Conditional logistic regressio n was used to estimate the multivariate-adjusted odds ratio of each ri sk factor. Family income was positively and significantly associated w ith breast cancer, showing a significant dose-response trend. High par ity above three showed a significant protective effect. There was a pr ominent protective effect from breast feeding. The longer the duration , the smaller the risk of breast cancer. The protective effect of brea st feeding was significant only in women who had more than three deliv eries.