Long-Term Use of Desogestrel Pill Associated with Slightly Elevated Brain Tumor Risk

Recent research published in The BMJ has revealed that the extended use of the progestogen-only contraceptive pill desogestrel for over five years may be linked to a minor increase in the risk of developing intracranial meningioma, a type of brain tumor. The study, conducted in France, highlights the need for awareness regarding the potential risks associated with long-term contraceptive use.

Intracranial meningiomas, which are usually non-cancerous, can sometimes necessitate surgical intervention. Although the risk associated with desogestrel is deemed low--one in every 67,000 women using the pill for an extended period may require surgery for meningioma--researchers emphasize that this risk dissipates within one year after discontinuing the medication.

Historically, there has been limited research investigating the risk of meningioma related to specific types of progestogens, particularly concerning long-term use. To fill this gap, scientists aimed to evaluate the risks linked to both short-term (less than one year) and prolonged (one to seven years or more) use of desogestrel, as well as other progestogens such as levonorgestrel, whether used alone or in combination with estrogen.

The findings stem from analysis of data obtained from the French national health data system (SNDS), which included 8,391 women who underwent surgery for intracranial meningioma between 2020 and 2023. Each case was matched with ten control subjects of the same age and geographic location who did not have meningioma, resulting in a total of 83,910 women in the study.

Factors that could influence the results, such as the use of other known high-risk progestogens in the six years preceding the study, were taken into account. The results indicated a slight increase in risk for those who used desogestrel continuously for over five years, while shorter usage durations or having ceased desogestrel for more than one year did not present a heightened risk. Interestingly, the risk was significantly increased among women over 45, those with meningiomas located in the front or middle regions of the skull, and those who had previously used other high-risk progestogens.

The researchers estimated that among 67,000 women taking desogestrel, one would require surgery for intracranial meningioma, while this number dropped to 17,000 for those who used the pill for more than five continuous years.

In contrast, no increased risk for meningioma was observed in women using levonorgestrel, whether alone or combined with estrogen, regardless of the duration of use.

It's important to note that this observational study cannot definitively establish a cause-and-effect relationship, and the authors acknowledged potential gaps in the SNDS database that may have influenced the findings. They also couldn't factor in genetic predispositions or exposure to high-dose radiation, which might have impacted the results.

Despite these limitations, the use of extensive real-world data, including histories involving other high-risk progestogens, contributed to the reliability of the findings and helped minimize bias. Consequently, the authors recommend that desogestrel be discontinued if a diagnosis of intracranial meningioma is made, advocating for patient monitoring rather than immediate surgical intervention.

Neurosurgeon Gilles Reuter, in a related editorial, suggests that while direct evidence linking desogestrel to meningioma is still needed, ceasing the use of this contraceptive upon diagnosis may prevent unnecessary surgeries, similar to existing knowledge regarding other high-risk progestogens.