First there were THINX, the period panties.

Now, Flex, another startup trying to change how women deal with their periods every month, has raised $1 million.

Flex makes menstrual discs. The product most resembles a menstrual cup like the Diva Cup, but is meant for one-time use like a tampon. The disposable disc sits up toward the cervix, collecting all menstrual fluid.

SEE ALSO: Some transgender men need period underwear like this

The biggest draw Flex promises is that the menstrual disc provides "mess-free period sex." Women (or anyone having a period) can keep the disc in during sex, and it'll contain all bleeding.

The company also says the discs aren't linked to Toxic Shock Syndrome, the infection women can get from wearing a tampon for too long.

Menstrual products are subject to regulations from the Federal Drug Administration. The FDA has extensive guidelines for pads and tampons and categorizes menstrual cups as a category exempt from certain regulations. There is no category for menstrual discs, an FDA spokeswoman said, and those devices would be regulated as menstrual cups.

Flex submitted itself to the FDA, in fact, as a menstrual cup. The company recently acquired its competitor Softcup, allowing it to corner the market on menstrual discs.

SEE ALSO: 5 ways to celebrate Menstrual Hygiene Day around the world

Flex raised $1 million in funding this month in a round led by a Bay Area startup incubator, according to Crunchbase.

While its website is full of testimonials gushing over the ease of using Flex — and how it makes sex more enjoyable — the product hasn't started shipping to customers yet.

Maybe the menstrual disc could change how women approach sex during their periods — for those who do avoid it, the product has potential to make things more comfortable.

Until Flex becomes more widely available, you can order a sample online for $3.95 in shipping and handling, or preorder a subscription for $15 a month.

Or you can order a uterus crop top. Or both.