Mixed
Lifestyle interventions (diet and exercise) significantly improve sperm normal morphology and progressive motility in men with obesity, whereas bariatric surgery and pharmacotherapy (metformin/liraglutide) show no clinically significant improvements in semen parameters or DNA damage.
If you are overweight and trying to conceive, focus on sustainable lifestyle changes (diet and exercise) rather than seeking surgical or pharmacological weight loss solutions solely for fertility. Lifestyle changes have been shown to improve sperm morphology and motility, whereas surgery and weight-loss drugs have not shown consistent benefits for semen quality in this population.
Fixed-effect meta-analysis identified improvements in sperm normal morphology (Mean difference = 0.59%, 95% Confidence interval = [0.23, 0.94]), and progressive motility (10.56% [8.97, 12.15]) following a lifestyle intervention... Random-effects meta-analyses of pre-post outcomes identified no clinically significant semen parameters or DNA damage changes following bariatric surgery.
Why this rating
Based on 10 studies (5 RCTs, 5 quasi-experimental), but GRADE quality is not explicitly stated as high for lifestyle; bariatric surgery was rated 'Very Low'.
Source
The effect of obesity interventions on male fertility: a systematic review and meta-analysis
Andrew Peel et al. · Human Reproduction Update · 2025
DOI 10.1093/humupd/dmaf025
Related findings · Mixed
- Bariatric surgery (VSG and RYGB) is the most effective and sustainable treatment for obesity, producing marked and sustained weight loss that non-surgical interventions cannot match.Strong
- Severely protein-deficient diets (2–3% energy) induce lean body mass loss and metabolic imbalance, whereas adequate protein intake (0.66 g/kg/d minimum) is a prerequisite for maintaining muscle, bone, and physiological function.Strong
- For patients with Class III obesity (BMI >39.9 kg/m2), metabolic bariatric surgery (MBS) is significantly more effective than any currently approved medication, with BilioPancreatic Diversion (BPD) showing the highest estimated weight loss.Strong
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