Obesity Linked to Low Sperm Quality, Semen Volume

An illustration of sperm
An illustration of sperm
Obese men have lower semen volume, number, concentration, and motility, as well as a higher prevalence of oligospermia and asthenospermia.

Lower semen volume, number, concentration, and motility were found in obese men, as was a higher prevalence of oligospermia and asthenospermia, according to recent findings published in Andrologia.

In a retrospective study of 1285 men seeking infertility treatment at a clinic, 201 (15.6%) were clinically obese (body mass index [BMI] ≥30). Age, BMI, smoking status, and a history of diabetes were assessed and adjusted for, as each has been identified as a risk factor for infertility.

Obese men were more likely to currently smoke or to have once smoked (12.3% obese vs 6.6% nonobese), and to have diabetes (68.6% obese vs 54.8% nonobese). Researchers examined sperm count, motility, concentration, and morphology using the computer-aided semen analysis (CASA).

When comparing all sperm parameters, including volume, sperm count, concentration of spermatozoa, progressive motility, average motility, average path velocity, average curve speed, multiple defects, midpiece defects, pyriform heads, head width, and head ellipticity, obese men had worse sperm quality than nonobese men.

Obese men were also more likely to have oligospermia (OR 1.67; 95% CI, 1.15-2.41, P =.007) and asthenospermia (OR 1.82; 95% CI, 1.20-2.77, P =.005). The higher risk of oligospermia and asthenopermia, as well as a lower sperm concentration and motility, remained after researchers analyzed men with diabetes alone.

The absence of data on other confounders such as hypertension and hyperlipidemia limits the study, as does the high prevalence of diabetes in the cohort.

Obese men have lower sperm quality and a higher risk of oligospermia and asthenospermia. “Clinicians may need to factor in paternal obesity prior to assisted reproduction,” concluded the researchers.

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Ramaraju GA, Teppala S, Prathigudupu K, et al. Association between obesity and sperm quality [published online September 19, 2017]. Andrologia. doi:10.1111/and.12888