Reproductive factors and breast cancer risk in Palestine: A case control study

Early age at menarche, late age at menopause, and late age at first full-term pregnancy are linked to a modest increase in the risk of developing breast cancer (breast ca). This study aims to investigate the reproductive determinants of breast cancer among women in the West Bank of Palestine. A structured questionnaire was used to collect data in a case-control study (237 registered cases and 237 controls). A multivariate analysis model was used to adjust for the association between women's reproductive factors and breast ca risk. This study was approved by Al Quds University Ethical Research Committee and the Ministry of Health research unit.

In the multivariate analysis, menarche after 13 years of age, use of oral contraceptives for more than two months, and hormonal contraceptives use significantly doubled the risk for breast ca (Adjusted Odds Ratio (AOR) = 2.03, 95 % CI: 1.21-4.37, p < 0.011 and AOR = 2.2, 95 % CI: 1.24-4.01, p = 0.008, respectively). Women who used hormone replacement therapy (HRT) were significantly associated with higher odds (5 folds) of having breast ca versus those who did not use them (AOR 5.02, 95 % CI: 1.93-13.06, p = 0.001). Similarly, nulliparous women showed 6 times the odds of breast ca compared with women with one or more children (p = 0.005). Also, parental consanguinity marriage (AOR 2.59, 95 % CI: 1.53-4.36, p = 0.001) and positive family history (AOR 3.88, 95 % CI: 2.19-6.87, p = 0.001) of the condition can be strong determinants for breast ca in this study.

This study provides clear evidence that the use of reproductive hormones, whether as a birth control tool or for therapeutic purposes, must be rationalized worldwide and in Palestine in particular.