The Duchess of Cambridge is opening up about the meditative method that helped her deliver all three of her children and helped her cope with pregnancies made challenging by hyperemesis gravidarum (HG), a seriously debilitating form of pregnancy nausea and vomiting.

The former Kate Middleton says she relied on hypnobirth, which is routinely used at the hospital where she delivered. In a new interview on the Happy Mum, Happy Baby podcast with Giovanna Fletcher, Kate explained, “I saw the power of it really, the meditation and the deep breathing and things like that—that they teach you in hypnobirthing—when I was really sick and actually I realized that this was something I could take control of, I suppose, during labor,” she said.

The Duchess explained: “It was through hyperemesis that I really realized the power of the mind over the body because I really had to try everything to try and help me through it.”

So what is hypnobirthing?

Well, it’s not the party trick hypnosis commonly portrayed in pop culture. It’s more of a form of meditation proven to help mothers relax during childbirth. It involves visualization, breathing techniques, guided meditation and sometimes massage.

It can be used during vaginal births and C-sections (and, as Kate proves, even when you’re not giving birth but dealing with other challenges). Research indicates hypnobirth may make labor faster and reduce the risk of C-section, and that it can reduce a mom’s fear and anxiety. Classes on hypnobirthing are available in most major cities (many experts recommend taking them when you’re around 25 to 30 weeks), and several companies offer online courses as well.

Colleen Temple shares her experience. “Pre-hypnobirthing, I would literally cry on the spot when I thought about going into labor. Post-hypnobirthing? I felt empowered, strong, prepared and very ready to birth my baby. It transformed my mindset completely,” she previously wrote for Motherly.

“With the help of the meditations and affirmations used in hypnobirthing, the fear of the unknown that I had before the course started shifted into the ability to truly trust that my body and my baby were going to do exactly what they needed to do to bring my little one safely into this world,” shares Temple.

The mind can be a powerful thing, and Temple and the Duchess have plenty of company on team hypnobirth. Mogul mama Jessica Alba is also a fan. She told Ellen it’s not weird, and is something women can involve their partners in. “My husband takes me through sort of a meditation. He’ll say, ‘you’re relaxed, and you’re floating on clouds while you’re going through labor and your contractions. I’m just concentrating on breathing and staying relaxed,” she explained.

The Duke of Cambridge wasn’t quite as into it as Alba’s husband, but that’s because it was more of Kate’s thing. “I’m not going to say that William was standing there sort of, chanting sweet nothings at me. He definitely wasn’t! I didn’t even ask him about it, but it was just something I wanted to do for myself,” she said on the Happy Mum, Happy Baby podcast.

Every mama should have things she wants to do for herself, and pregnant or not, meditation can be a great form of self-care.

[A version of this post was previously published April 26, 2018. It has been updated.]