SEP 2, 2026 · JOURNAL ARTICLE
Age at first sexual intercourse and frailty: Mendelian randomization and population-based evidence from NHANES and UK Biobank.
Sexual Medicine
Mendelian randomization with consistent genetic signal across sexes, supported by large population cohorts showing L-shaped associations, but observational design limits causal inference and source explicitly cautions against causality claims.
Reported
MR effect estimate (earlier AFS o…β = -0.30; 95% CI, -0.36 to -0.25
MR effect estimate malesβ = -0.23; 95% CI, -0.30 to -0.16
MR effect estimate femalesβ = -0.22; 95% CI, -0.30 to -0.13