GLP-1 WEIGHT-LOSS DRUGS MAY BOOST FERTILITY IN MEN, REVIEW FINDS

A review of existing clinical trials suggests that glucagon-like peptide 1 (GLP-1) drugs, currently prescribed to treat diabetes and obesity, may improve testosterone levels and sperm quality in men with obesity. Scientists from Warwick Medical School examined studies documenting testosterone levels in male participants taking GLP-1 drugs. The review found preliminary evidence that these medications could offer reproductive benefits alongside their established weight-loss effects. Researchers stated that the findings highlight the need for larger randomised clinical trials to assess male fertility outcomes more thoroughly.

Previous research established that obesity is strongly associated with reduced sperm quality and dysregulation of the male reproductive system. One trial reviewed involved 30 men with low testosterone who received either testosterone replacement therapy or a GLP-1 drug; both groups showed increased testosterone after 16 days of treatment. A second study treated 25 men with type 2 diabetes and low testosterone with either a GLP-1 drug or testosterone replacement therapy over 24 weeks; both groups achieved higher testosterone levels, though the testosterone replacement group experienced greater increases. However, sperm quality improved significantly in the GLP-1 drug group, with the proportion of sperm with normal shape and size increasing from 2 per cent to 4 per cent.

Scientists concluded that GLP-1 drugs "may improve reproductive hormones and semen parameters in obese hypogonadal men." The review acknowledged that evidence remains limited and heterogeneous across studies. Researchers emphasised that larger randomised clinical trials are necessary to establish whether these reproductive benefits represent a genuine advantage of the medication class. GLP-1 drugs have previously been associated with potential benefits against dementia and cancer in addition to weight loss.