SAN FRANCISCO — Products promising vaginal tightening for women who’ve gone through childbirth and are unhappy with the state of their private parts are gaining attention online, concerning medical experts who call the claims a health hazard.

Oak gall products, made from wasp nests, are being sold in online stores. Oak gall is produced when a wasp deposits its eggs in an oak tree. The tree responds by secreting tannic and gallic acids to form a ball-shaped nest around the larva. The full-grown wasps eventually breaks out of the nest and fly away. According to an article by Lad Bible, the leftover oak galls have been used by people in South East Asia for many years as a medicinal aid to prevent tearing during childbirth.

Backers of oak gall for vaginal rejuvenation claim they can be administered by boiling them and eating them, once a day for 40 days, or being ground up and applied to the affected vaginal area as a paste, with warnings that a burning sensation will follow.

Doctors say using this method will actually dry up the vagina increases the risk of abrasions during sex, and HIV transmission as a result. In her blog entry posted on May 16, high-profile gynaecologist Dr. Jen Gunter writes “Here’s a pro-tip, if something burns when you apply it to the vagina it is generally bad for the vagina.”