According to latest research, long term Hormone Replacement Therapy increases the risk of breast cancer. Hormone Replacement Therapy is a medical treatment, especially undergone by postmenopausal women to artificially increase the hormone levels of estrogen or progesterone. The risk of breast cancer is more in women who have undergone HRT after menopause than women who have not. Recent research has confirmed the link between HRT and breast cancer. Doctors usually advise women who have had breast cancer to not take HRT. Even for those women who have not had breast cancer, HRT increases the risk.

In 2002 when millions of women in the US stopped undergoing HRT, there was a drastic decline in the rate of breast cancer. According to another study published in The Lancet, 1,000 additional women died from ovarian cancer between 1991 and 2005 because they were using HRT, and that 1,300 extra cases of ovarian cancer were diagnosed in the same period. Initially most women took HRT, because it lowers the risk of serious illnesses as heart disease and dementia. For those suffering from postmenopausal symptoms, short-term use of hormone replacement can give relief and is also considered to be safe.