Going against the commonly held belief that hormone replacement therapy increases the risk of breast cancer; new Canadian research says it poses no threat to women carrying the BRCA1 mutation that places them between three to seven times more likely to develop breast cancer than women without the mutation.

Analysing data from 472-women carrying the BRCA1 gene mutation, researchers at Women’s College Hospital linked those on hormone replacement therapy with a 42% reduction in the risk of developing breast cancer.

Often women carrying the BRCA1 mutation have their ovaries removed to lower their risk of breast cancer in an operation called oophorectomy or ovariectomy, an operation that brings on menopause, which leads doctors to prescribe HRT for relieving the severity of menopausal symptoms, such as, hot flashes, dry skin, decreased libido and irritability.

However, the new findings about HRT should reassure women opting for preventive oophorectomy before menopause. While, subsequent studies are still required, even though observational studies do not find any link between HRT and increased risk of breast cancer in carriers of mutated genes, subsequent clinical trials show HRT increases the risk of recurrence in breast cancer survivors.

Meanwhile, even though earlier studies raised an alarm about HRT raising the risk of breast cancer, stroke and other heart conditions, the impact on the risk of breast cancer in post-menopausal women with a BRCA1 gene mutation remains unclear.

Hormone replacement therapy can involve only estrogens or estrogens together with the male hormone Progesterone, or progestin - a synthetic hormone mimicking progesterone.