Period-Proof Underwear for Teens: How It Works

If the first thing that crosses your mind after reading the words ‘period underwear’ is ‘huh?’ then read on…

Period underwear is the greatest innovation in menstrual products since the last century — and we’re not just saying that. Since adhesive pads were introduced in the 1960s, there has been very little innovation in the menstrual product space — until now. The following is the only explainer you’ll ever need when it comes to understanding period underwear and all the wonderful, magical things it is capable of. 

What are they?

In short, period underwear is a replacement for a pad, tampon or menstrual cup. Everyone has a preferred method of period protection — if you’re not quite sure what your teen's is, this is a good place to start — and may be more comfortable with using some products over others. For example, if your tween or teen is squicked out by the internal aspect of tampons but cringe at the diaper-like qualities of a pad, then period underwear might be the right solution for them.

Do they work?

In short, yes! Kt by Knix underwear contains a special gusset (the built-in absorbent liner) equipped with with special technology fabric that can absorb a significant amount of blood. Because everyone bleeds differently, we have three different levels of absorbency to accommodate all types of periods.

Our medium absorbency underwear is for light days and can absorb 3 tampons or pads worth of blood. Our high absorbency underwear can hold 4–8 tsp (20–40 ml) of blood, or the equivalent of 4–8 tampons or pads. And our super absorbency — basically the Mack truck of period underwear — can absorb 9–12 tsp or about 9–12 regular tampons worth of blood. If your teen is prone to leaks, our period underwear can be worn as backup protection in addition to a pad, tampon or cup — your teen knows their body best and should do whatever is most comfortable for them. 

How exactly do they work?

It’s all in the layers. Every pair of Kt by Knix period underwear comes equipped with three hard-working layers of fabric that keep your child smelling fresh and feeling dry. The anti-odor top layer wicks away moisture from skin using natural seaweed fibre; the middle-layer absorbs the liquid and locks it in; and the leak resistant outer layer keeps any liquid from spotting their clothes.


How do I wash them?

That’s easy. Just toss them in the washing machine alongside the rest of your clothes. If you’re concerned about blood transferring from the panties and onto other clothes, you can give them a quick rinse before hand, but it isn’t necessary. You can find more details on wash and care here.

Anything else?

Actually, yes. In the US alone, approximately 12 billion pads and 7 billion tampons are discarded each year. By choosing reusable period underwear, you’re leading the charge towards a more sustainable future. So give yourself a little pat on the back if you’re ready to help your child make the switch.

If you have more questions, you can always get in touch with the Knix team at, or send us a message on one of our social media platforms (TikTok, Instagram) and we’d be happy to answer.

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