From Blood Sugar to Baby Plans: GLP-1 RAs & Male Fertility

GLP-1 medications, otherwise known as GLP-1 receptor agonists (GLP-1 RAs), have been grabbing headlines lately - not just for helping people manage type 2 diabetes and shed pounds, but also in the context of… male fertility?

Specifically, a swirl of online speculation has some wondering: Do GLP-1 RAs impact your ability to have children?

GLP-1 stands for glucagon-like peptide-1, a naturally occurring hormone released by your intestines when you eat. It helps regulate blood sugar by stimulating insulin, reducing glucagon (a hormone that raises blood sugar levels), slowing stomach emptying, and decreasing appetite.

GLP-1 RAs are medications that mimic this hormone, and they're revolutionizing the treatment of type 2 diabetes and obesity. But as more people, including younger adults, are prescribed GLP-1 RAs, especially for weight loss, questions are surfacing about how these medications might affect reproductive health.

Before you ditch your medication or panic-Google sperm analysis clinics, let's take a look at what the current science says.

The Link Between Pant Size and Sperm Count

Here's the short version: researchers are paying attention, and early results are… actually pretty encouraging. The connection between GLP-1s and male fertility isn't fully understood, but what we do know points to some possible benefits, especially for men who are obese or have type 2 diabetes.

According to a recent review of pre-clinical and clinical studies, GLP-1 receptors have been identified in testicular tissue, including Leydig cells (which produce testosterone), Sertoli cells (which help support sperm development), and even sperm cells themselves. This suggests GLP-1 RAs may play a more direct role in testicular function than previously thought.¹

Let's break it down further.

Obesity and type 2 diabetes are major risk factors for male infertility. They interfere with testosterone production, impair sperm quality, and even disrupt hormone signaling in the brain (through the hypothalamic-pituitary-gonadal axis).

Studies have shown that²:

• Obese men are more likely to have oligospermia (low sperm count) or even azoospermia (no sperm in semen).
• Excess fat tissue increases estrogen levels while reducing testosterone, both of which can impair sperm production.
• Insulin resistance and inflammation, linked with obesity, also appear to reduce sperm motility and increase DNA fragmentation in sperm cells.

We know that GLP-1 RAs support weight loss and glucose control, but studies are showing a correlation with helping fertility by addressing some of the root causes of male reproductive dysfunction.

Testosterone

One of the more promising findings is that GLP-1 RAs may help raise testosterone levels, particularly in obese men with a form of low testosterone known as functional hypogonadism. It's called "functional" because the hormone-producing structures are still intact, but they aren't working properly due to external or systemic influences.

In a clinical study of obese men treated with liraglutide (a type of GLP-1 RA), researchers found a significant increase in serum testosterone levels, beyond what would be expected from weight loss alone.³

Sperm Quality

Researchers have also looked at how GLP-1 RAs affect sperm metabolism - the processes by which sperm generate energy, move, and function properly.

In one study, incubating sperm cells with exenatide (a GLP-1 RA) resulted in improved sperm motility and better DNA integrity.³

Before Jumping on the Bandwagon

So far, the research is cautiously optimistic, especially for men with metabolic conditions. But it's not all clear skies. We don't yet have large, long-term human studies specifically designed to look at fertility outcomes in men taking GLP-1 RAs. That means there's still a lot we don't know about how dosage, duration, and underlying health conditions might shape the fertility picture.

To complicate things, some findings have reported that GLP-1 RAs might reduce testosterone pulses (the natural rhythm in how testosterone is released) or delay recovery of sperm functionality after stopping the medication.⁴ One small study in animals suggested that liraglutide impaired semen parameters temporarily, though sperm quality seemed to improve after stopping the drug.

Right now, the evidence doesn't support. In fact, if you're using a GLP-1 RA for obesity or diabetes, it may be doing your reproductive system more good than harm, especially if you had metabolic-driven fertility issues to begin with.

But - and this is a big but - we still need longer-term, controlled clinical trials to fully understand how GLP-1 RAs affect testosterone, sperm production, and fertility outcomes in healthy men and those with pre-existing fertility concerns.

If you're trying to conceive or have concerns, talk to the male fertility specialists at Georgia Urology before making medication changes. As with anything related to hormones, metabolism, and fertility, the answer is rarely one-size-fits-all.

References:

1. Cannarella, R., Calogero, A. E., Condorelli, R. A., Greco, E. A., Aversa, A., & La Vignera, S. (2021). Is there a role for glucagon-like peptide-1 receptor agonists in the treatment of male infertility?. Andrology, 9(5), 1499-1503. https://doi.org/10.1111/andr.13015.
2. Varnum, A. A., Pozzi, E., Deebel, N. A., Evans, A., Eid, N., Sadeghi-Nejad, H., & Ramasamy, R. (2023). Impact of GLP-1 Agonists on Male Reproductive Health-A Narrative Review. Medicina (Kaunas, Lithuania), 60(1), 50. https://doi.org/10.3390/medicina60010050.
3. Cannarella, R., Calogero, A. E., Condorelli, R. A., Greco, E. A., Aversa, A., & La Vignera, S. (2021). Is there a role for glucagon-like peptide-1 receptor agonists in the treatment of male infertility?. Andrology, 9(5), 1499-1503. https://doi.org/10.1111/andr.13015.
4. Du Plessis, S. S., Omolaoye, T. S., & Cardona Maya, W. D. (2024). Potential impact of GLP-1 receptor agonists on male fertility: a fable of caution. Frontiers in physiology, 15, 1496416. https://doi.org/10.3389/fphys.2024.1496416.