The objective of this meta-analysis is to evaluate the association between hormone therapy use and the risk of developing central nervous system (CNS) tumors, particularly meningioma and glioma.

Hormone therapy is widely used for contraception, disease treatment, and as hormone replacement therapy in women. Many studies have attempted to establish the relationship between the use of exogenous hormones and the development of CNS tumors; however, the results remain inconclusive.

Pubmed, Scopus, and Web of Science were searched for studies reporting the association between hormone therapy use and CNS tumor risk. Outcomes included overall risk for CNS tumors, meningioma, and glioma, reported as odds ratios (ORs) and hazard ratios (HRs). Analyses were conducted in R (version 4.4.2), with p < 0.05 considered significant.

The analysis of the 19 studies involving 2.398.681 patients demonstrated a significant association between hormone therapy use and the overall risk of CNS tumors (OR = 1.69; 95% CI, 1.28–2.23; p < 0.001; I² = 98.5%). Subgroup analysis revealed an increased risk for the development of meningioma (OR = 2.10; 95% CI, 1.52–2.91; I² = 98.6%), whereas for gliomas the exposure may not be associated with an increased risk (OR = 0.90; 95% CI, 0.64–1.27; I² = 84.9%). The overall risk of CNS tumors was also expressed using hazard ratios (HR = 1.18; 95% CI, 0.97–1.45; p = 0.097; I² = 71.0%), showing an insignificant trend favoring non-use of hormone therapy, with an increased risk observed for meningioma (HR = 1.59; 95% CI, 1.09–2.32; I² = 72.8%), while based on the analyzed data, hormone therapy use may not appear to increase the risk of glioma development (HR = 0.99; 95% CI, 0.86–1.16; I² = 36%).

This meta-analysis suggests that exogenous hormonal therapy increases CNS tumor risk in women, mainly driven by meningioma, with no consistent association for glioma.