Progestogen Contraceptives Linked to Higher Brain Cancer Risk

Women who used progestogen-only contraceptives faced a significantly elevated risk of developing meningioma, a type of brain tumor, according to a large-scale Danish study published this week. The research analyzed data from over 1.8 million women aged 15 to 49 over a 20-year period, from 1995 to 2014, and identified a correlation between progestogen use and meningioma diagnosis.

The study, which utilized nationwide prescription data and the Danish Cancer Registry, found that the risk of meningioma increased with the duration of progestogen use. Specifically, women using oral progestogen contraceptives had a 1.4 times higher risk, while those using injectable progestogens saw their risk increase by 2.1 times. Intrauterine devices (IUDs) containing progestogen were also associated with a 1.3 times higher risk of meningioma. The researchers noted that the risk was particularly pronounced for higher doses and longer durations of use.

Meningioma is the most common type of primary brain tumor, and while often benign, it can cause significant health problems due to its location and potential to grow large. The study's authors, led by Dr. Lene Mellemkjær from the Danish Cancer Society Research Center, emphasized that while the absolute risk remains low for any individual woman, the widespread use of progestogen contraceptives warrants attention to this potential side effect. The findings suggest that the cumulative exposure to progestogens may play a role in the development of these tumors.

This research builds upon previous, smaller studies that hinted at a possible link between hormonal contraceptives and meningioma. The Danish study's large sample size and long follow-up period provide more robust evidence for this association. The authors recommend further investigation into the biological mechanisms that might explain this link and suggest that clinicians should be aware of this potential risk when prescribing progestogen-based contraceptives, especially for long-term use. The study did not find a similar increased risk associated with combined estrogen-progestogen contraceptives.