A Danish population study published in JAMA this week confirmed an association between progestogens in hormonal contraceptives and meningiomas, the most common brain tumour in adults – but the absolute risk for most progestogens is very low, Australian experts emphasised.

About the study

The case‑control study drew on Denmark’s linked national health registers, allowing researchers to analyse prescription histories, cancer diagnoses and demographic data.

From a background population of more than 3 million women aged 15–59, the authors identified 2606 meningioma cases. After excluding those with previous use of selected hormones (including all women with a prior HRT prescription), prior cancer, or recent immigration, 1473 cases and 14,717 matched controls were included.

The study grouped progestogens by route of administration and dose, including combined oral contraceptives, progestogen‑only pills, high‑ and low‑dose levonorgestrel IUDs and injectable medroxyprogesterone.

Several progestogen-containing contraceptives were associated with a small increased risk of meningioma, but the number needed to harm varied greatly depending on the specific progestogen used and the age group.

“Medroxyprogesterone showed the highest risk with relatively low numbers needed to harm, whereas all combined oral contraceptives, oral progestogen-only contraceptives, and IUDs had relatively high numbers needed to harm, especially among the youngest women,” the authors explained.

The highest risk was seen in the oldest women, as well as those who had exposure within the past year, they noted.

Does the research warrant a change in prescribing?

Dr Alex Polyakov is a Clinical Associate Professor from the University of Melbourne’s Faculty of Medicine and Medical Director of Genea Melbourne.

He says for most types of progestogens, the increase in risk is very small.

“For combined pills and Intra-Uterine Devices (IUDs), the absolute excess risk is negligible and shouldn’t change clinical practice,” he says.

However, the study found risk was highest with medroxyprogesterone injections (odds ratio of 4.55 (95% CI 2.19-9.45)).

“I’d caution against reading this paper as a mandate to start switching women off their contraception. It gives us no validated high-risk profile, and honestly, the more useful question isn’t ‘which patient?’ but ‘which drug?’” Clinical Associate Professor Polyakov notes.

“The answer to that is unambiguous: depot medroxyprogesterone. An odds ratio above four, numbers needed to harm an order of magnitude worse than anything oral, and the French and US data have been saying the same thing for a while now. Where there’s a sensible alternative, that’s the one I’d think hard about.”

“Everything else is a matter of weighing. A woman with a known or previously treated meningioma is the obvious case to steer away from these agents — we know withdrawal can shrink these tumours. Age matters too, because the absolute risk climbs in older women, as does long intended duration and a history of the high-dose progestogens we already worry about.”

Putting it in perspective

Clinical Associate Professor Polyakov says it’s important to emphasise the risk is about current or recent use.

“The risk applies to women using these drugs now or recently, and it disappears within about five years of stopping. So, when your patient who took the pill in her thirties rings up in a panic, you can tell her, truthfully, that she’s carrying essentially at no residual risk,” he says.

“There will be some panic as these headlines write themselves. Meet it with reassurance, not the prescription pad.” – Clinical Associate Professor Polyakov

“For the combined pill and the levonorgestrel coil, the risk is real but tiny, and it sits against benefits we too easily forget to mention: no unwanted pregnancies, less ovarian and endometrial cancer, lighter and less painful periods,” Clinical Associate Professor Polyakov sums up. “Put simply, the added meningioma risk is smaller than her chance of dying on the drive to your surgery.”

Pregnancy also increases the risk

Dr Gino Pecoraro, an Associate Professor of obstetrics and gynaecology at the University of Queensland and past president of the National Association of Specialist Obstetricians and Gynaecologists agrees that it’s crucial to help patients maintain perspective.

“Meningioma occurs in roughly one in 10,000 people, with women having roughly double the rate that men do. It is well known that meningiomas grow during pregnancy and if extra progesterone is given, but decrease in size once the pregnancy is completed or progesterone withdrawn,” Associate Professor Pecoraro says.

“It is important to point out that a pregnancy in the preceding year also increases the risk of meningioma and carries other potential risks,” he says.

“Pregnancy in Australia carries a maternal mortality rate of 6.6 per hundred thousand, while the Australian five-year survival rate following meningioma diagnosis is greater than 90%.”

Non-progestogen-containing contraceptive options including barrier methods and copper-containing IUDs may be considered for women who are concerned about the association between progestogens and meningioma, Associate Professor Pecoraro adds.

For more information:

“Contraceptive Progestogens and Incident Meningioma,” Lundstrøm et al., JAMA Network Open, 2026, doi: 10.1001/jamanetworkopen.2026.22603