The Impact of Body Mass Index on Semen Parameters: A cross sectional study

Abstract

Introduction: Infertility is an emerging health issue  across the world/. Obesity is another growing health concern, which is seen associated with adverse health outcomes. Several people had investigated the effects of obesity on male infertility, with inconclusive findings. Hence the present study aimed to assess the relationship between Body Mass Index (BMI) and the various parameters of semen (volume, sperm count, vitality, motility and morphology).

Methods: This was a cross-sectional study involving  272 men aged 20 – 52 years. The participants were categorized into four BMI groups as underweight, normal weight, overweight, and obese. Semen samples were analyzed. In the correlation study, Spearman’s correlation was used. Independent variables were tested on the dependent variables using Analysis of Variance (ANOVA) and Multivariate Analysis of Variance (MANOVA) to find out the effects of BMI on semen parameters while controlling effects of various covariates (age, smoking and alcohol consumption, occupation, ethnicity and education).

Results: Correlation analysis showed no statistically significant correlations between BMI and semen parameters. However, comparing the BMI groups revealed statistically significant differences in semen parameter (p<0.05). The normal weight, overweight and obese groups had better semen quality than underweight. Underweight men had sperm count(16±20.78 million/ml), vitality(13.6±7.09%), progressive motility(4.33±4.93%) and morphology(1.33±0.57%). The effect of BMI on semen parameters was further confirmed by MANOVA study with Wilks’ Lambda=0.802, F=3.273, p<0.05.

Conclusions: Semen quality was adversely affected in underweight groups compared to other groups. Thus emphasizing importance of keeping healthy BMI in order to have a better reproductive health. 
Keywords:  BMI, Semen parameters, Underweight.