The record
Meta-analyses of predominantly case-control data report summary estimates of roughly 1.28-1.31 for perineal talc use and ovarian cancer, with a marked divergence between study designs: OR 1.35 (95% CI 1.27-1.43) in case-control studies versus OR 1.06 (95% CI 0.90-1.25) in cohort studies.
Claim scope
The design-dependent split, quantified with CIs, from Epidemiology 2018;29:41-49. 24 case-control studies (13,421 cases) and three cohort studies (890 cases).
What this source does not establish
It does not resolve whether the case-control excess reflects causation or recall bias.
Limitations
Pair with PMID 31472245 (Reprod Toxicol 2019;90:88-101), which reports OR 1.28 (95% CI 1.20-1.37) and notes significant risk 'in Hispanics and Whites' — a defense-adjacent critical review reaching a similar summary estimate. Note also PMID 36652669 (Epidemiology 2023;34:376-384) found 'some evidence of recall bias for genital talc use among ovarian cancer survivors,' which bears directly on the case-control/cohort divergence.
Source
Pmid — 28863045