Body mass index and sperm quality: effects of overweight and underweight

Abstract

We previously reported a negative association between body mass index (BMI) and sperm motility and seminal alpha-glucosidase concentrations (NAG), suggesting that epididymis may be a target organ for weight-linked alterations. In this study, we analyzed a possible association between BMI and semen quality in 4876 patients with no genitourinary diseases or toxin exposure, including morbidly-obese and underweight patients. We performed multivariate regression analysis using BMI,, age and abstinence as independent variables and demonstrated that BMI was inversely and significantly associated with semen volume, total sperm count, motility and NAG (slopes: -0.01, -1.33, -0.18, -0.75; p<0.05); in addition, we found a significant negative associations between BMI and viability, morphology and HOST.