Story highlights Gwyneth Paltrow's lifestyle website cites benefits of putting a jade egg into your vagina

Gynecologists warn that the rocks could actually be harmful

First, Gwyneth Paltrow raved about vagina steaming; now her lifestyle website, Goop, wants you to stick a $66 rock in your vagina.

Earlier this month, Goop posted a story called " Better Sex: Jade Eggs for Your Yoni ," which claims that these eggs -- supposedly an ancient "guarded secret of Chinese royalty" used by queens and concubines -- harness the "power to cleanse and clear" making them "ideal for detox, too."

The article also claims putting a jade egg into your vagina for hours at a time can improve your sex life, balance your menstrual cycle, and "intensify feminine energy," among other things.

The jade eggs are now sold out, but the women's health experts Health spoke to say you should steer clear anyway. Walking around with a rock clenched in your lady parts is just the latest addition to the list of things you shouldn't do to your vagina.

The site Goop offered jade and rose quartz eggs for sale, though both were shown as sold out.

"Many people have this idea that if it's natural it must be good, useful, and not harmful," says Lauren Streicher, MD, associate clinical professor of obstetrics and gynecology at Northwestern University, and author of " Sex Rx: Hormones, Health and Your Best Sex Ever ." "To which I always say, arsenic is natural, but that's certainly harmful."