Scientists have discovered that long-term use of certain progestogen drugs is linked to a higher risk of "meningiomas", which are usually non-cancerous tumors that form in the tissues around the brain. It was also suggested that the risk of meningiomas was higher in women who used the drugs for more than a year.
Progestogens are similar to the natural hormone progesterone and are commonly used in birth control pills, gynecological conditions such as endometriosis and polycystic ovary syndrome, and hormone replacement therapies during menopause.
Researchers at France's National Agency for the Safety of Medicines and Health Products argued that most meningiomas are usually non-cancerous and grow slowly, but they often need to be surgically removed because they can put pressure on the brain.
Using data from the French national health system, the researchers examined the health histories of 18,000 women with an average age of 58 who had surgery to remove intracranial meningiomas between 2009 and 2018. The study found that long-term use of progestogens (more than 12 months) was associated with a higher risk of meningiomas requiring surgery.
Prof. Paul Pharoah, a cancer epidemiologist who spent 20 years studying hormone-related cancers at Cambridge University before setting up a laboratory at Cedars-Sinai hospital in California, said there are many different types of progestogen and not all pose the same risk.
"There is no increased risk of meningioma in women taking commonly used birth control pills or hormone replacement therapy. It is important that women do not stop using birth control pills without consulting their doctor."
