[Causal relationship between obesity and male infertility: A two-sample Mendelian randomization study]

Area of Science:

• Genetics
• Reproductive Medicine
• Public Health

Background:

• Obesity is a global health issue with potential links to various health outcomes.
• The relationship between obesity and male infertility requires clarification regarding causality.
• Genetic predisposition plays a role in both body mass index (BMI) and male infertility.

Purpose of the Study:

• To investigate the causal effect of genetically predicted body mass index (BMI) on male infertility risk.
• To utilize Mendelian randomization (MR) to establish a causal link, minimizing confounding factors.

Main Methods:

• A two-sample Mendelian randomization (MR) study was conducted using large-scale genome-wide association study (GWAS) data.
• Univariable MR (UVMR) with inverse variance weighting (IVW) was the primary analysis method.
• Sensitivity analyses and multivariable MR (MVMR) were performed to ensure result robustness and assess direct effects.

Main Results:

• UVMR revealed a significant causal relationship between genetically predicted BMI and an increased risk of male infertility (OR: 1.237, P = 0.001).
• Sensitivity analyses indicated minimal bias in the study findings.
• MVMR confirmed a direct causal effect of genetically predicted BMI on male infertility risk, even after adjusting for confounders.

Conclusions:

• Genetically predicted higher BMI is causally associated with an increased risk of male infertility.
• These findings underscore the importance of weight management for male reproductive health.
• Further research is needed to elucidate underlying mechanisms and develop targeted prevention strategies.