How Marijuana Affects Fertility | Dr. Natalie Crawford & Dr. Andrew Huberman

Added: 2026-05-06

[00:00:00]Cannabis use is probably the most concerning thing that I see in clinical practice. So both you can just say if that many are using it in pregnancy, let's extrapolate to how many are using it beforehand. And ultimately something that we are just now getting robust data on because it's hard to study something when it's illegal.

[00:00:17]All cannabis use is hugely detrimental to sperm for sure across the board, right? Both production, the quantity of sperm, testosterone production, also the quality of the sperm, specifically the DNA fragmentation inside the head of the sperm to the degree that female partners who conceive from a male partner who's using cannabis have much higher miscarriage rates than partners who do not utilize cannabis. And I will say clinically in the IVF lab when I see embryos halt at that male developmental stage on day three, we say, "Oh, here's a young couple. They've got no embryos and we were expecting them to have some.

[00:00:49]When we go back nine out of 10 times, he is using cannabis that he previously denied. So it is one of the most movable factors right now in this country for improving, you know, fertility outcomes.

[00:01:03]For women, cannabis use in the prior year can decrease the eggs you get at egg retrieval by 25% and can decrease fertilization rates by 28% and can increase miscarriage rates, therefore decreasing live birth rates.

[00:01:17]So huge numbers in science, right? I mean like we get excited when something is a few, you know, percentage points different, but these numbers are really high to the degree that it's really easy to sit here and say if you're trying to get pregnant the fastest, if you want to have the best pregnancy outcomes, or even you want to have the best hormones you can, have longevity of your ovaries, or have the best sperm counts, or the most testosterone, cannabis use should not be a part of that. And THC crosses the placenta directly. And THC levels in, you know, edibles are usually the highest. So I think it's really important that sometimes people are like, "Oh, well, I don't smoke it, so I'm okay." We want to be really careful that this is not something your body is meant to be exposed to when we want to think about the core of how your body is meant to function.

[00:02:05]>> [clears throat] >> Critical message. Thank you so much. I I've been put through the ringer around this cannabis thing cuz I've hosted people that said it does increase the risk of psychosis in certain, typically young males, although not everyone. I've been accused of all sorts of things related to that, then had someone on who confirmed that, someone who refuted it, and cannabis, I believe, is recently rescheduled from schedule one, no, at the federal level it's assigned to no medical application, to schedule three. So there's going to be a lot more cannabis use going forward. It's so critical that people hear this. And the argument I always hear, and it's always dudes, typically on X, they'll say that they smoked a lot of weed and they got their or took edibles and they got their wife or girlfriend pregnant X number of times and it sort of becomes this sort of point of boasting and then I never want to make the comment, but I'll make it now. It's like yeah, but you're talking about brain development in your kid. And I'm not saying your kid is dumb, but I'm saying they're maybe not as smart as they could be or as um healthy as they could be. I'll just say that cuz I'm talking to the guys out there and that's how we talk to one another. Yeah, you had a bunch of kids, but they could be a lot healthier. And so I think to me, it just seems like anything that one could do since it's a ostensibly a short-term decision, certainly for the man, right? The woman who's going to breastfeed should probably avoid cannabis during breastfeeding, too. You see where I'm going with this.

[00:03:27]>> outcome is so important, right? And when we want to think about even just male cannabis use. Yes, sperm count, etc. Decreases the sperm quality. That sperm quality is important for programming of the embryo, for how the placenta develops. If the placenta is not as good, you know, association with earlier birth. I mean, it's just not worth the risk when the outcome is so important, right? We're all weighing risk every day with different decisions. To me, there's a lot harder decisions you have to make, but you know, nicotine use, cannabis use, alcohol use, like the data here, none of that is advantageous for your health, especially if we're looking primarily through a fertility lens, a hormone lens, or even >> [clears throat] >> or specifically a pregnancy lens. Like there's there's no place for it.

[00:04:12]You can choose to do what you want with that data, right? And people will always say, "I know so-and-so who did this and they got pregnant." And there will always be those people, but you're the one making decisions for your journey. And the recommendation is even stronger if you are having infertility, if you are older, depending on your scenario, because you want to control what you can because you can't control everything. So I call those the behavioral toxins that there's really no place that we need to add these to the world if we're talking about how do we get my body to function optimally. It's interesting that um certain substances get uh politicized. You know, in the past can experience this thing that you can tell with some degree of of friction. Um in the past, cannabis was associated with the left. It was like pro-cannabis was left. Now, pro-cannabis is actually very strongly correlated with the with the with the um the laws, anyway.

[00:05:03]Uh this rescheduling is very And you watch the media just kind of pivot and it's just very clear that they're not paying that the media is in the traditional media isn't paying attention to the to the actual data. It's sort of like, "How can we use this as a weapon?"

[00:05:17]On both sides. On both sides.

[00:05:20]>> [music]