[zasz]

This is actually a really good replacement for pads. They say their underwear can hold one to six teaspoons. There are five milliliters to a teaspoon, and according to Wikipedia, the average period produces one to six tablespoons total. There are three teaspoons to a tablespoon. So their underwear should be able to easily cope with one day's worth of flow, since it should be able to cope with half a period to an entire period's worth.

Assuming their manufacturing process isn't too toxic, this could be vastly more environmentally friendly than pads and tampons. The downside of reusable, durable items of this nature, is that it's gross and requires handwashing.

[jlees]

Odour would be one of the main concerns, but I love the idea of this as an incredibly transformative hack.

[araneae]

I question whether the top construction is wicking enough to be comfortable. Pads (and diapers) have a top layer through which the moisture goes through, keeping the top relatively dry. This is actually a lot more challenging for menstruation, as it tends to be considerably more viscous.

[istorical]

I think you neglected the factor that flow varies over the course of a period with a shape like sin(x) from x=0 to x=3.14. Or in other words it starts off slow, peaks, then peters out.

[zasz]

Being a woman, yes, I am entirely aware of that. Unless you have a single day where you're pushing out two tablespoons, though, which is very unlikely, my point still stands.

[peterwwillis]

The average tampon will hold 5mL. Sanitary pads hold 5mL-15mL. These things hold 29mL.

[oskdfjgfgg]

And many women go through 3 pads a day during their peak. Which is much more convenient than having to change your underwear, and have somewhere to put them to carry them around with you until you get home.

[peterwwillis]

Those "many women" may have menorrhagia and should consult with their doctor for treatment, yet very few realize this and just think they are "heavy flow" people, which puts them at risk for disease and other medical problems. I should think, though, that it's much more convenient to carry around one pad than three, and for the rest of people is probably a relief to not need one at all.