Are contraceptives linked to brain tumours?

If you’re worried about reports linking some hormone treatments with the risk of developing meningioma brain tumours, this Q&A aims to explain what the study involved and answer some of those concerns. 

What was the study linking contraceptives and brain tumours? 

The reports stem from analysis of French national healthcare system data, the results of which were published in The British Medical Journal in March 2024.

That data involved 18,061 women who had had surgery to remove intracranial meningiomas between 2009 and 2018. Their average age was 58. Each case was compared with those of five healthy women to form a control group of just over 90,000 women. 

What did the data show? 

Researchers found that those who had used a particular injectable contraceptive for a prolonged period of time (more than a year) were associated with a greater risk of intracranial meningioma that required surgery. 

The injection involved is known under the brand name Depo-Provera and has the primary ingredient medroxyprogesterone acetate.

It was linked to a risk of developing meningioma that was 5.6 times higher than in the control group.

The study also found:

The oral pills medrogestone and promesgestone were linked to risks 4.1 and 2.7 times higher, respectively. 

It’s important to note that this was an observational study of medications most commonly prescribed in France. No direct causal link was found, and the risks found are very small. 

What’s the context around that risk?  

Primary brain tumours themselves are considered relatively rare. Figures provided by Cancer Research UK show they accounted for around 3% of new cancer cases between 2017 and 2019.  

Around 12,700 people are diagnosed with a brain tumour in the UK each year. This includes tumours in the central nervous system such as the spinal cord, the covering of the the brain (meninges) and nerves leading from the brain.  

Out of every 100 brain tumours diagnosed in England between 1995 and 2017, 27 were meningiomas. 

What should I do if I’m taking contraceptives? 

The mostly commonly prescribed mini pill and morning-after pill were not associated with any increased risk in this study. But if you have concerns because you are taking prescribed contraceptives or HRT, experts advise talking to your doctor or healthcare team. 

They can help you: 

It’s important for them to understand which specific medication you are using as different formulations can have different effects on the body. 

Have drug manufacturers commented on the research findings? 

Pfizer, which manufactures Depo-Provera, has published a statement saying: “We are aware of this potential risk associated with long-term use of progestogens and, in collaboration with regulatory agencies, are in the process of updating product labels and patient information leaflets with appropriate wording.” 

The MHRA has worked with the Government and Pfizer to issue advice to medical practitioners and The Faculty of Sexual and Reproductive Healthcare says it will continue to monitor the evidence.

Can I use contraceptives if I have a meningioma? 

It’s important to get medical advice as some contraceptives are contra-indicated for some types of brain tumours because of a known link with hormone receptors.

The NHS guidance on injectable contraceptives is here 

Why more research is needed 

While this study provides valuable information, it also has limitations. For example, it did not include the use of over-the-counter contraceptives or the different formulations used in other countries.  

Evaluating similar data about populations in other countries would help us better understand the relationship between hormone treatments and the risk of developing a brain tumour. 

This highlights the need for further research into the causes and potential treatments for all brain tumour types. 

If you have further questions or concerns, our Information and Support team is here to help.