EFFECTS OF DIABETES MELLITUS ON SPERM QUALITY AND FERTILITY OUTCOMES

Abstract

The relationship between paternal metabolic diseases, particularly diabetes mellitus, and male fertility remains complex and unclear. This systematic review synthesized 112 qualifying articles published since 2013 examining the impacts of body mass index, diabetes, metabolic syndrome, weight loss medications, bariatric surgery, and exercise on semen quality and fertility outcomes. The evidence indicates that obesity, diabetes, and metabolic syndrome adversely affect multiple male fertility parameters, including sperm quality and DNA integrity. Male obesity increasingly shows detrimental effects on live birth rates, whether through natural conception or assisted reproductive technology.

Lifestyle interventions such as diet and exercise can enhance male fertility markers; however, the intensity, type, and duration of exercise appear crucial. Weight loss medications, including metformin and glucagon-like peptide-1 agonists, demonstrate mixed effects—both positive and negative—on male reproductive health. Gastric bypass surgery may improve hormonal imbalances but has inconsistent effects on semen parameters.

Regarding diabetes specifically, its prevalence among infertile men ranges from 0.7% to 1.4%, while infertility prevalence in diabetic men ranges from 35–51%. Male diabetes negatively impacts couple fertility, and subfertile men may face increased diabetes risk. Type 1 diabetic men show reduced childbirth rates compared to controls, particularly with longer disease duration. Pregnancy rates are lower in couples where the male partner has diabetes undergoing assisted reproduction. However, no studies adequately assessed diabetes treatment effects on male fertility and semen quality.

Overall, available data suggest diabetes mellitus impairs male reproductive health and couple fertility. Further extensive studies are needed. Health practitioners can currently utilize these findings to promote proactive lifestyle changes and targeted interventions for improving male reproductive health.