A case cancer control study of reproductive in breast cancer.

The role of reproductive factors, such as, parity, age at menarche, age at first child's birth have been investigated in a hospital based case-control study, for their independent as well as combined influences on the incidence of female breast cancer. The study indicates that except for parity, these factors have no influence on the age at onset of the disease. Parity is positively correlated with age at onset. The patient and the control groups were found to be similar in respect of age at first child's birth and age at menarche, but the patient group was significantly lower both in parity and age at onset of the disease. Both these factors are negatively associated with the incidence of breast cancer. Therefore, preventive action should be focussed on young women with low parity.