Well-established risk factors such as tobacco smoke, occupational exposure, and Schistosoma haematobium infections do not fully explain the lower risk of bladder cancer for women compared to men. Recently, an association was reported between women who were married to agricultural workers and bladder cancer risk. We investigated whether proxies of estrogen exposure (age at first childbirth, number of babies delivered, and age at menopause) act as effect modifiers on the association of para-occupational exposure to agricultural work and bladder cancer among Egyptian women. Data from a multi-center Egyptian case-control study of 222 cases and 471 controls were used to examine the association. No evidence of effect modification was observed for these proxies. Later age at first childbirth may be an independent risk factor for this malignancy (AOR= 1.63; 95% CI 1.17, 2.27). Future studies can help identify sensitive sub-populations of Egyptian women who are more likely to develop bladder cancer.