A new sports betting strategy has people predicting WNBA players' menstrual cycles

Well, the Phoenix Mercury fell to the Las Vegas Aces in the WNBA Finals over the weekend. Their sweep of the finals solidified what the sports world is calling the Aces’ dynasty. This was their third title win in four seasons.

It was a tough loss for the Mercury after an inspired season, and it comes as the WNBA is more popular than ever — with record investment, viewership and sales this season.

But that popularity for women’s sports has come with some questionable attention, too. Molly Longman tells us more about the world of online betting around the WNBA and how a new sports betting strategy has men making bets based on their “predictions” about the players’ menstrual cycles.

Longman reported the story for Wired.

Full conversation

LAUREN GILGER: OK, so I've got, you've got online gamblers here claiming to be able to predict the players menstrual cycles and betting on it. Just as, you know, the WNBA, this sport is exploding. I, I mean I have to start with the question of sexism here. Like is there anything equivalent to this for the NBA?

MOLLY LONGMAN: Yes, I wouldn't say there is anything equivalent to this. So yes, you're right, it's just WNBA.

GILGER: Tell me, Molly, what was your reaction when you heard about this?

LONGMAN: Yeah, absolutely. So I was so curious when I first heard about it. Actually a friend of mine said that he knew someone who did this. And I was immediately curious, and I was thinking, oh, that sounds very scientifically dubious. And the doctors confirmed that, that I spoke to. But yeah, so for the story, I spoke to one man online who is making these predictions, and they have just tens of thousands of likes on these posts.

They have tons of shares. And he told me that his strategy was essentially to look at a WNBA player, look at her history from college to her time in the WNBA and see if there were any cyclical monthly trends in performance where there might be a dip. And he had seen one study that said essentially their the players self-reported worse performance on their late luteal phase.

But of course if you look into the study and dig into it, they say no, actually this is one thing, smaller sample, but it's not across the board and there needs to be much more research to bear that out. And the doctors I spoke to of course said no, you can't really predict that, especially from the outside.

GILGER: You spoke with one sports medicine physician who called it "silly," right? That was the word.

LONGMAN: Yes, she called it silly. Others have used the word sexist, especially because, you know, that's just one piece of it, like the predicting the cycle, if you even can do that, which of course you can't. There are so many people with irregular cycles. People are on birth control.

But the other piece is like there really isn't research saying that women are better or worse at sports based on different phases of their cycle and certainly not these players at the top of their game. So I think that's another piece of this that is a trope, and not exactly true when you write to the experts and dig into it.

GILGER: Right. Playing into these sexist tropes. Tell us more about this, this guy you interviewed who's making videos, getting tons of attention for this, for, for what he claims are sort of proven successful strategies of tracking this.

How does he say he uses actual data to make this happen? This goes beyond just periods, right. Like he's tracking patterns that go back to college, as you said, for some of these players.

LONGMAN: Yeah, yeah. Which, you know, one of the people I spoke to also said that's concerning on several levels, especially in the post-Roe world with privacy being so important, especially around this. And another expert called it quite invasive. But yeah, so he, he said that he has been correct on 11 out of 16 of his period-related predictions. Hard to say.

But then, yeah, he basically said that he'll look at dips in trends, and he'll look at two different stats that are, he said, basically like how often someone makes baskets, their percentage of how much they help the team on and off the court, and kind of compare those numbers. But again, many of the experts I spoke to said that's, that's just, that's just not possible from an outsider's perspective.

GILGER: Yeah, but people really are betting on this, which is wild. I want to talk about the kind of, you talked about the stereotypes. Like this just plays into these kind of longstanding false stereotypes about women.

But it could have real implications, as you point out in your story. Like, like WNBA players make way less money than their male counterparts in the NBA. Could perpetuating these kinds of stereotypes just make that worse?

LONGMAN: Right. Absolutely, yes. As we all know, WNBA players make pennies compared to their male counterparts. And especially, you know, they're in the middle of collective bargaining negotiations right now, talking about salary and also revenue sharing. And I think of as it relates to the story, one of my sources put it really well, and she says, if there's this narrative that 25% of the month women are not going to be competing at the same level, there are very dangerous repercussions to such a negative stigma.

And I think it's true. And I think, you know, when they're in these negotiations, we see it with the WNBA and also with women's soccer. You know, people will make all kinds of excuses for why the female athletes, the women make less. But I think it comes down to it, and there is a piece of sexism in that.

And especially if you're saying hormones are part of it, that's really like saying the quiet part out loud. But I think these are athletes at the top of their game, and their hormones are not going to be predictors, as the science shows of how well they do.

GILGER: Molly, before I let you go, have any WNBA players commented about this at all?

LONGMAN: Not yet, no. I've seen a lot of comments on the story that are like, are men OK? But haven't heard from any WNBA players yet.