Understanding Sperm Quality, Lifestyle Factors, and Male Fertility

About the expert

Dr. Joshua Halpern

Posterity Health

Dr. Joshua Halpern MD MS is a board-certified and fellowship-trained Reproductive Urologist. He serves as both the Regional Medical Director in the Northeast and Chief Scientific Officer for Posterity Health. He is also on faculty at Northwestern University Feinberg School of Medicine.

Silvia

When we talk about variability in the context of sperm quality in medical terms, what kind of bandwidth are we talking about?

Joshua

There is more variability when it comes to sperm quality and semen parameters than we often acknowledge. This variability is influenced by numerous factors, including environmental exposures and lifestyle. Sperm production follows a cycle of approximately two to three months, meaning that if there's a negative stimulus, it takes a few months for semen parameters to reflect improvements after that stimulus is removed.

Even without external factors, there's inherent variability in semen parameters. Studies have examined the optimal timing for repeating a semen analysis, with results varying depending on whether it’s repeated a week, two weeks, four weeks, or even eight weeks after the initial test. These fluctuations demonstrate that semen analysis is not a perfect test, and we must consider this natural variability when interpreting results.

Silvia

What do you typically recommend to men who want to improve their sperm quality? How tailored can your advice be, beyond medication or assisted reproductive technology (ART)?

Joshua

Our recommendations have to be tailored because every individual has unique exposures and risk factors that can impact sperm quality. Before talking about exercise or diet, we need to eliminate behaviors that we know have a clear detrimental impact—such as daily marijuana use, frequent hot tub or sauna exposure, smoking, and binge drinking. For example, even one prolonged exposure to extreme heat can significantly set back sperm production. These are “low-hanging fruit” interventions that we prioritize.

Once those harmful exposures are addressed, we can focus on positive changes—regular exercise, strength training, and dietary improvements can all contribute positively. But it’s essential to start by removing the known negative factors first.

Silvia

Which role do supplements play in improving sperm parameters? Are there any substances that have proven to be statistically significant?

Joshua

For every supplement out there, you’ll find at least one retrospective study suggesting it works and another suggesting it doesn’t. However, two well-designed randomized controlled trials, the MOXI trial and the FAZST trial, were published in major medical journals and found no significant benefits from the supplements they studied in the specific contexts they examined.

That said, some supplements have better supporting data than others. Coenzyme Q10 likely has the strongest evidence for improving semen parameters. I generally also recommend a high-quality men’s multivitamin, which helps address any underlying deficiencies. At Posterity Health, we’ve developed a supplement with what we believe to be the best evidence-based ingredients, but I always remind patients to keep expectations realistic—supplements likely won’t dramatically shift the needle, though they also pose minimal risk beyond cost.

Silvia

Now, there are clear cases where intracytoplasmic sperm injection (ICSI) is the best option and cases where lifestyle modifications can make a significant difference. But what about edge cases? How do you determine when to try lifestyle interventions first and when to move on to ART?

Joshua

This requires an individualized approach, considering both male and female factors. Thresholds can be helpful, particularly total motile sperm count, which has strong predictive value. However, I don’t rely on hard cutoffs because so many variables are at play.

Factors such as how long the couple has been trying to conceive, the presence of female infertility, and the potential for improvement in the male partner’s semen quality all contribute to our decision-making. Collaboration with reproductive endocrinologists is essential. In some cases, we may be able to improve sperm parameters enough to allow for a less invasive conception method, but if female factors are limiting, ART may still be necessary.

Even when a couple is pursuing ART, optimizing sperm quality can still improve their chances of success, so there’s almost always value in making improvements.

Silvia

I’d like to touch on metabolic syndrome and diabetes because they’re so prevalent. These conditions affect not just fertility but also the pregnancy and long-term health of both parents and the baby. Where do you see your role in managing these issues, and how do you collaborate with other specialists?

Joshua

Great question. One of the most underappreciated aspects of male fertility care is that reproductive urologists often serve as the first point of contact for men’s overall health. Many young men seeking fertility evaluations don’t have a primary care physician. In fact, our group published a study showing that about a third of men coming in for a fertility workup lacked a PCP.

This means we often diagnose conditions like diabetes or obesity during fertility evaluations. If a patient presents with retrograde ejaculation, for example, testing may reveal undiagnosed diabetes. It’s our job to not only address fertility concerns but also ensure men receive appropriate medical care for their overall health.

Metabolic disorders impact sperm quality in multiple ways, including hormonal imbalances and erectile dysfunction. Managing these conditions requires collaboration with PCPs, endocrinologists, and reproductive specialists to ensure optimal outcomes, not just for conception but also for the long-term health of both partners and the baby.

There’s also increasing interest in how medications for metabolic conditions impact fertility. For example, there was a study suggesting metformin use at conception might be linked to birth defects, though follow-up research refuted that. Similarly, we're still learning about the impact of GLP-1 receptor agonists, like Ozempic, on sperm parameters. We need more data to fully understand these interactions.

Silvia

So, in these cases, do you present patients with the available information, are transparent about any lack of data, and make decisions together?

Joshua

Exactly. For instance, some GLP-1 medications have package insert warnings recommending stopping them eight weeks before conception, but the data is not definitive. We help patients navigate these uncertainties with shared decision-making.

Silvia

What are the biggest misconceptions about improving sperm quality, both from patients and providers?

Joshua

The biggest misconception is that infertility is primarily a women’s health issue. Male factors contribute to about 50% of infertility cases, yet many people, including some healthcare providers, don’t fully appreciate that.

Another misconception is that sperm parameters can’t be improved. In reality, lifestyle changes, medications, and even surgeries can significantly enhance sperm quality for many men. The challenge is that these improvements take time—typically three months, sometimes longer for cases involving hormone imbalances or anabolic steroid use.

Silvia

Thank you for your time!