Long-Term Use of Hormonal Contraceptives Could Lead to Increased Risk of Brain Tumors


Key Points

  • A link has been identified between long-term hormonal contraceptive use and increased occurrence of gliomas.
  • Female sex hormones may increase risk of some cancer types, but also may diminish some cancer risk in certain age groups.
  • Researchers say risk-benefit evaluation currently favors the continued use of hormonal contraceptives in eligible users.

Taking a hormonal contraceptive for at least 5 years is associated with a possible increase in women’s risk of developing a glioma, according to a study by Andersen et al published in the British Journal of Clinical Pharmacology.

Study Details

While little is known about the causes of glioma and other brain tumors, evidence suggests that female sex hormones may increase the risk of some cancer types (though there is also evidence these same hormones may reduce cancer risk in certain age groups).

“This prompted us to evaluate whether using hormonal contraceptives might influence the risk of gliomas in women of the age range who use them,” said research team leader David Gaist, MD, PhD, of Odense University Hospital and the University of Southern Denmark. Researchers drew data from Denmark’s national administrative and health registries, enabling them to identify all the women in Denmark who were between 15 and 49 years of age, and had a first-time diagnosis of glioma between 2000 and 2009.

Key Findings

Researchers found 317 cases of glioma from this group of women and compared each of these cases with eight age-matched women who did not have gliomas. “It is important to keep this apparent increase in risk in context,” said Dr. Gaist. “In a population of women in the reproductive age, including those who use hormonal contraceptives, you would anticipate seeing 5 in 100,000 people develop a glioma annually, according to the nationwide Danish Cancer Registry. While we found a statistically significant association between hormonal contraceptive use and glioma risk, a risk-benefit evaluation would still favor the use of hormonal contraceptives in eligible users.” 

Dr. Gaist pointed out that it is important to carry on evaluating long-term contraceptive use in order to help women choose the best contraception for them. He also emphasized that the findings need to be interpreted with care.

“Despite that, we feel our study is an important contribution, and hope that our findings will spark further research on the relationship between female hormonal agents and glioma risk,” he said.

Dr. Gaist and Lene Andersen, MD, of Odense University Hospital, are the corresponding authors for the British Journal of Clinical Pharmacology article.

The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.