The impact of obesity and metabolic health on male fertility: a systematic review.
Level 3 - non-randomized controlled study
Systematic review of predominantly observational cohorts and mixed non-randomized studies
PubMed 37839720 · doi:10.1016/j.fertnstert.2023.10.017
What was done
The authors conducted a systematic review searching the MEDLINE database for articles published between 2013 and 2023. They included 112 studies evaluating the effects of body mass index, diabetes, metabolic syndrome, exercise, weight loss medications (such as metformin and GLP-1 agonists), or bariatric surgery on semen parameters, sperm quality, sperm DNA integrity, and fertility outcomes across natural and assisted conception.
What was found
The abstract reports qualitative trends without providing numerical data, effect estimates, or confidence intervals. Paternal obesity, diabetes, and metabolic syndrome were associated with reductions in semen quality, compromised sperm DNA integrity, and reduced live birth rates. Physical exercise was generally associated with improved male fertility markers, influenced by type and intensity. Weight-loss medications showed mixed beneficial and detrimental effects, and bariatric surgery improved hormonal imbalances but yielded mixed semen parameter outcomes.
Why it matters
This review synthesizes a decade of evidence showing that paternal metabolic health significantly influences semen biology and clinical fertility outcomes. It highlights the need to differentiate the reproductive impacts of lifestyle versus pharmacological and surgical metabolic interventions.
Limits
The abstract contains no quantitative meta-analysis, pooled effect sizes, or confidence intervals. The search was limited to a single database (MEDLINE) over a 10-year window. Findings for pharmacological and surgical weight-loss interventions remain conflicting and heterogeneous across the included literature.
Cited by
- supports Insulin resistance, metabolic disease, and obesity are the primary modifiable risk factors driving the decline in male fertility and sperm parameters.