San Francisco start-up The Flex Company has designed a tampon that allows women to experience "mess-free" sex during their periods.
The Flex tampon aims to help couples become more intimate by allowing them to have sex no matter the time of month.
Shaped like a curved disc, it works in a similar way to the Mooncup, a cup worn inside the vagina during menstruation. Flex fits against the cervix, creating a soft barrier that temporarily blocks menstrual blood.
It is disposable, and can be worn for up to 12 hours ? four hours longer than the recommended time for an average tampon.
As it contours to the shape of a woman's cervix, it can't be felt by either partner during sex. But it is not a form of contraception.
"Flex is so shockingly comfortable that women tell us they forget they're on their period while they?re wearing it," CEO Lauren Schulte said during a pitch at Y Combinator's Fellowship Virtual Demo Day.
"We've built a product that allows couples to increase their opportunity to have sex by 23 per cent," she continued. "The great tragedy of people avoiding sex on their period is that this is really the time when women want it most."

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According to gynecologist Jane van Dis, Flex has been is hypoallergenic, free of BPA plastic ? which is thought to have health implications ? and doesn't carry the risk of Toxic Shock Syndr...