Causality assessment · Emerging: progestogen class effect, under review

Medroxyprogesterone acetate and Meningioma: is the FAERS signal real?

n=11,275 co-reports · PRR 1,443.2 · ROR 1,868.2

Medroxyprogesterone acetate side-effect profile All assessments See in the full list

A written Bradford Hill assessment of one drug–event pair. The grade is a judgement about the signal, not a statement that this drug causes this event in any one person; FAERS counts are reports, not rates.

Emerging: progestogen class effect, under review

Medroxyprogesterone acetate ↔ Meningioma

n=11,275 co-reports · PRR 1,443.2 · ROR 1,868.2

Reporting over time (stimulated-reporting check)

Reporting spiked in 2024, 2025 — 98% of all 1,678 reports arrived in two years (2024–2025). A burst like this usually follows a regulatory communication, media coverage or litigation advertising rather than a change in the drug's effect; it inflates disproportionality for those years.

Bars: reports per year as a share of all FAERS reports for this drug, 2004–2025; amber = spike year (>3× the median share, ≥50 reports). Source: openFDA count=receivedate, retrieved 2026-10-09.

Medroxyprogesterone acetate is a progestin used for contraception, abnormal uterine bleeding and, at high doses, as hormonal cancer therapy. The progestogen class has been linked to intracranial meningioma: a French national cohort found a dose-dependent association with high-dose cyproterone acetate (Weill et al., BMJ 2021, PMID 33536184), which prompted European reviews that extended the meningioma warning across several progestogens. Meningiomas frequently express progesterone receptors, giving a plausible mechanism. Whether the effect size for medroxyprogesterone specifically matches cyproterone's is not yet settled, so this is graded "emerging/contested" rather than established — and the extreme FAERS PRR (1,443) substantially overstates the true risk once awareness and increased imaging are accounted for.

Weill A, et al. Use of high dose cyproterone acetate and risk of intracranial meningioma in women: cohort study. BMJ. 2021;372:n37 (PMID 33536184). European regulatory reviews of progestogens and meningioma (from 2020 onward). Signal emerging; the effect size for medroxyprogesterone is not established.

Bradford Hill viewpoint	Status	Note
Temporality (necessary)	partial	Association grows with years of use, but meningioma grows slowly and onset is hard to date
Strength	met	PRR 1,443 — but heavily inflated by awareness and screening bias
Consistency	partial	Clear for cyproterone; less well established for medroxyprogesterone specifically
Specificity	partial	A progestogen class effect, plausible via progesterone receptors
Biological gradient	met	Risk rises with dose (high-dose > low-dose) and duration
Plausibility	met	Meningiomas commonly express progesterone receptors
Coherence	met	Coheres with the receptor biology and with the wider progestogen literature
Experiment	partial	Reported meningioma regression after progestogen withdrawal is supportive
Analogy	met	Directly analogous to cyproterone-acetate-associated meningioma

This page's own qualitative read, not an automated/citation-gated assessment.

Not applicable in principle. Meningioma is a slow-growing tumor that develops over years; no contraceptive or hormone-therapy trial is long enough or large enough to detect it. This class of question is answered by long-term cohort studies and case series, not by trial adverse-event tables.