Women who take estrogen-only pills for at least 15 years run a markedly higher risk of developing breast cancer, according to a study of nearly 29,000 nurses. But no increased danger was found among those who took the hormone for less than 10 years.
Women who take estrogen-only pills for at least 15 years run a markedly higher risk of developing breast cancer, according to a study of nearly 29,000 nurses. But no increased danger was found among those who took the hormone for less than 10 years.