Is overweight a risk factor for reduced semen quality and altered serum sex hormone profile?

ObjectiveTo evaluate whether overweight and obesity are related to changes in serum sex hormone concentrations and semen quality.DesignCross-sectional study.SettingData from five previous population-based environmental studies of semen quality were combined into one database at a university hospital in Denmark.Patient(s)In total, 2,139 men provided data to the database.Intervention(s)Data on semen and blood samples and information on lifestyle and reproductive factors, including body mass index (BMI), were collected.Main Outcome Measure(s)Semen quality (volume, concentration, total sperm count, and motility) and serum concentration of sex hormones.Result(s)The T and inhibin B serum concentrations were 25%–32% lower in obese men in comparison with normal-weight men, whereas the E2 concentration was 6% higher in obese men. Overweight men (BMI, 25.1–30.0 kg/m2) had a slightly lower adjusted sperm concentration and total sperm count than did men with a normal BMI (20.0–25.0 kg/m2), but no reduction in sperm count was observed among the obese men.Conclusion(s)These results corroborate earlier findings that overweight and obese men have a markedly changed sex hormone profile in serum, whereas reduction of semen quality, if any, was marginal and below the detection limit of this large study.