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Three Common Causes for Infertility in Men

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Three Common Causes for Infertility in Men

Apr 28, 2022

Could something as simple as spending time in a hot tub or taking a supplement be impacting your fertility? Male infertility specialist Kelli Gross, MD, explains the top three most common things she sees in her practice and simple changes that can increase a man’s fertility.

Episode Transcript

Interviewer: For a couple that is having difficulty getting pregnant, as often as 40% of the time, it's actually an issue with the male partner. Why is that, and what are some of the more common things that can be causing infertility in men?

We're joined by Dr. Kelli Gross, a men's health specialist and Assistant Professor in urology at University of Utah Health.

Now, Dr. Gross, if we were to pick out the top three reasons why men might be infertile, what are they and how can they be treated?

Dr. Gross: So, number one, one of the top modifiable reasons that I see is exposure of the testicles to heat. What that commonly is, is a hot tub, bathtub, sauna. And the reason why is because sperm really likes the cooler temperature of the testicles. The testicles are outside of the body. They're about four degrees cooler than the rest of the body. And things like hot tubs, that increases the heat and the sperm just doesn't work as well, isn't produced as well.

People are surprised that those effects last about three months. Seventy-four days is the lifecycle of the sperm, so going in the hot tub once is going to potentially affect your fertility for the next three months.

Interviewer: Wow.

Dr. Gross: Yeah. People are always shocked by that number. Now, we found that things like showers don't necessarily make a big difference, the kind of underwear that you wear, those sorts of things. But a lot of direct heat from the testicle you do want to avoid.

Interviewer: I guess how big of a temperature change are we talking before we see that 74-day impact on the sperm count or functional sperm count?

Dr. Gross: I don't know if we necessarily know an exact number, but I usually advise patients the testicles are four degrees cooler than the rest of the body, so kind of keep it under that point.

Another common thing that we see is fevers. So after fevers, it's incredibly common to see abnormalities on a semen analysis.

Interviewer: Wow. Okay. So that's number one. That's pretty common. It's not something that's at the forefront of your mind. What about number two?

Dr. Gross: So number two would be something called a varicocele. Those are dilated veins to the testicle. So if you think about varicose veins in your legs, it's the same kind of thing. And they happen in about 15% to 20% of men overall, but we find it in up to about 50% of men who see a urologist for fertility issues. They are repairable surgically.

We think the reason why they have such an effect is potentially because it does trap heat. So the blood pools in those dilated veins, so it traps more heat in the testicles, which sperm doesn't like.

Interviewer: And what causes these veins? Is it just genetics? Is it just maybe lifestyle stuff?

Dr. Gross: It's mostly just genetics, kind of the way that you were born. They're incredibly common. So it's in part just the way that we're constructed, the way the veins have to travel such a long distance.

Interviewer: And so is this an outpatient procedure type of surgery? What kind of . . . what is involved in treating the varicocele?

Dr. Gross: Yes, it's an outpatient surgery. It takes about an hour more or less, depending on if we have to do both sides or what. We make an incision that's about an inch, inch and a half long, and then just divide all the veins. It's fairly straightforward as far as surgeries go. Not everyone needs it, but a fertility specialist can help determine if it's something that needs to be repaired.

Interviewer: Okay. So we have heat. We have an outpatient procedure if there are some extra veins or some varicoceles that have been formed. What about number three? What is the third most common thing?

Dr. Gross: So number three that I see very frequently is people who are on supplements that can potentially harm fertility or other medications. Testosterone, for example, is one of the biggest culprits that I see. Most other medications that are prescribed aren't going to have a big effect.

But there are certain other ones like Propecia or Finasteride, which is used for hair loss, that can potentially affect fertility. Cancer medications, unsurprisingly, can affect fertility. But the one that people don't really expect is supplements. They've done studies on supplements, and I've been absolutely shocked with what's actually in a lot of the supplements that we take. For example, there are steroid hormones. There are things like testosterone, including testosterone, that are in some of these supplements, even ones that aren't labeled, or that you would necessarily worry about. There's even oral testosterone, which is actually pretty bad for your liver. It's just not well regulated.

I see patients all the time who I look at their hormone panels and I'm like, "You may not be on testosterone, but there's something that you're taking that has testosterone in it." And we usually can pick something out and stop it and then those effects go away.

Interviewer: Wow. And so are these just over-the-counter type? Are we looking at like a daily multivitamin supplement? Are we looking at, say, muscle building, those things that you get in the big jugs at the supplement store?

Dr. Gross: Not usually the multivitamin, the Centrum or anything like that. Those are usually pretty safe. But it's like pre-workouts, even ones that aren't "boost your testosterone pre-workout," just regular pre-workouts, anything that's kind of marketed towards the erectile dysfunction, men's health kind of thing. I've seen potentially having issues with that.

Interviewer: And how long does it usually take for someone to see the effects go away after they stop taking it?

Dr. Gross: It can really vary. For example, with people who've been on testosterone for years, it can take up to about 18 months for that to come back. So in 90% of men it'll come back in about 18 months, but 3 months is usually a minimum. And some people won't come back in at all.

Interviewer: Okay. So those are three common things that can be causing male infertility. Now, Dr. Gross, how long should a couple be trying before they come and see a specialist like yourself?

Dr. Gross: So it's different for every couple. We generally say if after a year, definitely come in. But we won't question if it's sooner. It's easy to check to see if things are normal or not.