Modifiable key factors and semen quality in men undergoing preconception evaluation: a cross-sectional study.

Area of Science:

• Reproductive Medicine
• Andrology
• Public Health

Background:

• Male preconception lifestyle factors like smoking, alcohol consumption, and body mass index (BMI) can influence semen quality.
• The precise dose-dependent and nonlinear effects of these factors on male reproductive health are not fully understood.

Purpose of the Study:

• To investigate the dose-dependent and nonlinear associations between male lifestyle factors and semen quality.
• To provide evidence for targeted lifestyle guidance in preconception care.

Main Methods:

• Retrospective analysis of 3336 men's demographic data, lifestyle behaviors, and semen parameters.
• Utilized multivariable regression models with natural cubic splines, adjusting for age, abstinence period, and season.

Main Results:

• Smoking demonstrated a clear dose-dependent adverse effect on sperm concentration, total sperm count, and motility, particularly in men smoking >20 cigarettes/day or for >10 years.
• Former drinkers showed minimal improvement in sperm motility.
• Body mass index exhibited complex nonlinear associations with semen volume and sperm morphology, with optimal parameters in mildly overweight men, while obesity correlated with impaired semen quality.

Conclusions:

• Lifestyle factors play a crucial role in male reproductive health during the preconception period.
• Smoking cessation and weight management are vital for improving semen quality.
• Even modest weight modifications can significantly enhance semen parameters, underscoring the importance of personalized lifestyle interventions.