Estrogen is a compounded steroid which primarily functions as female’s sex hormones. Its main purpose it to trigger secondary sexual arousals and initiate menstruation. Though, this drug is therapeutically used for curing severe ailments like prostate cancer, breast cancer and osteoporosis, its over-dosage or wrong dosage, on the contrary, can augment the severity of these conditions. According to doctors, those women who take the supplement of estrogen hormone continuously for a period of more than 15 years are at a high risk of developing breast cancer.  

The consumption of estrogen pills especially in conjunction with progesterone for a lifetime drastically increases one’s vulnerabilities towards breast cancer. Women who experience early menstruation and late menopause tend to produce more stock of estrogen over their life. Excessive presence of estrogen, therefore, increases their risk for breast cancer. A woman suffering from breast cancer develops cancer cells dependent on estrogen. In such a case, estrogen replacement therapy proves disastrous as it promotes the tumor and multiplies the cancerous cells in the body. A woman may have breast cancer cells with relative sensitivity towards estrogen. Therefore, it is advisable to consult a health care practitioner before taking any random dosage of estrogen unmindfully.