Greatest-athlete-of-all-time Serena Williams and I have just started talking over Zoom when everything comes to an abrupt halt. “Are you in a car right now and don’t have a seatbelt on?” Williams asks with a tone only a mother would use. Okay, yes, I don’t have a seatbelt on while my Uber speeds up the West Side Highway. My cheeks flush as I click in, ashamed. “I couldn’t help myself,” the mother of two says. Now that I’m strapped in, she’s ready to talk.

The recent public discourse around Williams’s body—online commenters noticing a change in her physique and demanding to know how, exactly, it came about—isn’t anything new. “I’ve heard negative comments, along with a tremendous amount of positive comments, about my body my entire life,” says the 23-time Grand Slam winner, who announced her retirement on the cover of Vogue in September 2022. “For lack of a better way to say it, I don’t really care what people are saying about my body anymore. But what is important to me is transparency.”

That calling has led her to this very moment: Williams is ready to share that she’s on the GLP-1 drug Zepbound, a type of medication typically prescribed for diabetes and now also used for weight management. She accessed the drug through Ro and is now partnering with the telehealth company to talk about her experience. Williams’ husband, Alexis Ohanian, is an investor in the company and serves on its board. The athlete isn’t the only person who has revealed they are on one of the many versions of semaglutide—Oprah, Kelly Clarkson, Charles Barkley, and more have also gone on the record about using the drug.

“There’s a scene in my HBO documentary where you see my coach telling me, ‘You have to lose weight,’” she shares. “But it was so hard after I had [my first daughter] Olympia. I was literally on the court every day, doing nothing else. I had been the ultimate super-athlete, always in competition and being super-healthy my entire life, but I just could never get back to where I needed to be, no matter what I did.”

After the birth of her second daughter in 2023, the feeling compounded—and that’s when she learned about GLP-1 medications. “My whole life is being in the gym, working out, running, training, HIIT training, dancing, every single thing you can think of. I would always get to a certain point on the scale, but I could never get below that. That’s when I decided that it was time to try something different and got on the GLP-1 with Ro.”