Data Sheet 1_Combined assessment of body mass index and triglyceride-glucose index reveals metabolic risk phenotypes associated with semen quality impairment.docx

Men with both high BMI and high TyG showed the highest odds of reduced total motility (OR 3.63, 95% CI:1.99, 6.61), progressive motility (OR 3.21, 95% CI:1.74, 5.90), and normal forms (OR 2.78, 95% CI:1.57, 4.92). Men with low BMI but high TyG showed numerically higher impairment rates than men with high BMI but low TyG across motility and morphology outcomes. The incremental NRI of TyG beyond BMI ranged from 0.212 to 0.321 for these parameters (all P < 0.01).

Exploratory mediation analyses indicated that TyG statistically accounted for 35.9%, 33.9%, and 28.5% of the observed association between BMI and total motility, progressive motility, and normal forms, respectively.</p>Conclusions<p>BMI and TyG index were independently associated with impaired sperm motility and normal morphology, while the combination of BMI and TyG provided additional risk stratification. Elevated TyG may help identify metabolically at-risk men who are not fully captured by BMI alone, although further validation is required.</p>