Meta-analysisindependent cross-checkabstract checked I-ORG-139 standard review

Gynaecological surgery and dementia: newest pooled analysis

Associations of Hysterectomy and Oophorectomy with Dementia Risk: A Systematic Review and Meta-Analysis of Observational Studies.

Overview

Fu X et al.. J Clin Med 2026 · PMID 42796018 · DOI 10.3390/jcm15187247

Across all ages, removing the uterus or ovaries was not clearly linked to dementia.

Does the study support the specific claim? No · Methodological quality: moderate

Study explained simply

What did the researchers want to find out?: Pool procedure-specific dementia data
How was the study done?: Meta-analysis
How many people, animals or samples were studied?: Nearly 2.7 million women
What was actually found?: No clear associations
How large was the observed effect?: BO alone 0.99 (0.88-1.12)
What do the results mean in everyday life?: Any risk is probably confined to early surgery, if real
What are the study's limitations?: High heterogeneity
What does it say about Elawady's specific claim?: Limits the claim
Do the results apply to Germany and Europe?: Applicable
What can explicitly not be concluded from this study?: Cannot address oophorectomy before 45 specifically

Authors: Fu X et al.
Journal: J Clin Med
Year: 2026
Identifier: PMID 42796018 DOI 10.3390/jcm15187247
Verification: verified – PubMed efetch 2026-10-26; Crossref works API 2026-10-26
Retracted: no
Corrections: none
Extent checked: abstract only
Conflicts of interest and funding: Not stated in abstract.

Are hysterectomy and oophorectomy associated with dementia, distinguishing specific procedures?

Study design: Meta-analysis – Systematic review and meta-analysis of observational studies (procedure-specific)
Population: Women in observational studies
Country: Multinational
Period: Search to 20 August 2026
Sample size: 9 reports, 2,693,443 participants; 5 in meta-analyses
Inclusion and exclusion criteria: Explicitly defined procedures

Exposure / intervention: Hysterectomy alone; hysterectomy with BSO; bilateral oophorectomy
Comparator: No surgery
Endpoints: Dementia/Alzheimer's disease; MCI separately
Statistical methods: Inverse-variance random effects (REML) on log scale

Results: Hysterectomy alone: pooled ratio 0.94 (0.84-1.05; I2 82.2%). Hysterectomy with BSO: 1.04 (0.67-1.62; I2 83.6%). Bilateral oophorectomy alone: 0.99 (0.88-1.12; I2 75.6%).
Absolute risks: Not reported
Authors' conclusion: Procedure-specific analyses did not show a clear association with dementia/AD; heterogeneity, confounding and misclassification limit certainty.

Null pooled estimates with high I2.

Newest pooled evidence; does not stratify by premenopausal age as the claim does.

Georgakis 2019 (age <= 45 HR 1.70).

Applicable.

Limits the claim: across all ages no clear association; does not contradict a risk confined to early surgical menopause.

Multidimensional assessment
Multidimensional assessment
Authenticity of the source	verified
Methodological quality	moderate
Risk of bias	some concerns
Precision of results	moderate
Directness	indirect
Reproducibility	unknown
Consistency with the overall evidence	inconsistent
Regional transferability	high
Adequacy of the interpretation (by the archive)	not applicable

Age-stratified pooling.