Frequently asked questions

I don’t have to use a menstrual pad – seriously?

Our panties fully substitute for pads, tampons or a menstrual cup. This is also true for the lace cuts that you can order on our site, but the smooth cuts and our sassy mesh cut have a particularly effective absorbent layer of bamboo viscose (whereas bamboo is capable of absorbing up to four times more moisture than cotton), which makes them ideal for days of heavy flow. You are of course free to wear any of the models as a complement to your cup or with a tampon.

Won’t the wool be itchy?  I hate itchy woolen sweaters!

The merino wool that we use is incredibly soft and won’t scratch – that’s a promise. The individual fiber is 16.5 micrometers thick, which is why the woven fabric is smooth and soft to the touch.

But won’t they smell when I’m on my period?

Period panties don’t give off any odor. Wool naturally binds harmful substances, such as viruses and bacteria, and thus works against the build-up of odor. Bamboo has similar qualities. We’ve found zero need to add odor-suppressing agents!

I am afraid I’ll get all hot and...

Our panties take you out of the hothouse. Merino wool has thermoregulating capabilities and lets air through. The knitted bamboo viscose layer also breathes, thanks to its structure, and again helps keep temperatures stable. Finally, the membrane, for all its protective power, won’t let a drop of blood through, but is vapor permeable. That’s science talk for: “you’ll feel super comfortable”.

Won’t the panties rustle as I move around?

When we commissioned the development of the membrane, we were mindful of this particular aspect. Because of this, the membrane itself bends and folds without making the slightest noise. It is true that there is some inevitable friction where the membrane meets the other materials, so the panties will rustle a tiny bit as one layer rubs against the other. The SAYU team tested the acoustic aspects of the panties – yay, science! – and found that in a very quiet room, wearing panties only, you’ll be able to detect some rustling. Put on a skirt or a pair of pants, though, and you’ll no longer hear any rustling (also because of all the small sounds likely produced by your other clothes, shoes, or sportswear).

Can I wash the panties along with my other laundry?

You certainly can. It is advisable to rinse them first; wash them together with your laundry using liquid washing detergent (as opposed to washing powder), and set the spin speed of your machine to a maximum of 1,000 rpm. Follow this simple procedure to ensure that both the wool and membrane will last a long time and serve reliably

What washing detergent should I use?

The panties can be washed with liquid washing detergent. We recommend green or natural liquid washing detergent, which benefits both your laundry and the environment. For washing by hand, cold water is best – if you want to use soap, you should choose a soap that is wool-care compatible, such as lanolin soap or Marseille soap. If you don’t have such soap on hand, use shampoo. We advise against the use of gall soap or curd soap: over time, the wool will become brittle.

The panties need to be laundered at 40 degrees (Celsius) and are not suited for wash – I am worried about bacteria?

Wool is a natural protein fiber that, in and of itself, prevents decay and the multiplication of microbes. Bamboo has similar qualities. Both of the fabrics that we’ve used to make the panties are naturally antibacterial. There is no need to use additional laundry disinfectant; in fact, it’s wasteful.

How many washing cycles do the panties last?

We’ve chosen from the finest materials and fabrics. During product research, the membrane went through 30 washing cycles without any deterioration. The SAYU team members have put the panties through an endurance test, washing them intensively and frequently. The lace and elastic bands are holding up well, retaining their shape and color. The membrane remains fully functional. And the wool is as soft and caressing as it was on the first day. As long as you wash the panties according to the product care instructions and remember not to “rub” the merino wool when washing them by hand, these panties will look like new for a long time.

How come they don’t leak?

An impermeable membrane is sewn into the panties that reliably protects you. There is no need to worry about accidents.

What size should I pick?

You’ll find a size chart in the description for each individual product. Click on “SIZE CHART” to uncollapse the chart, below which you’ll also find tips on how to properly take your measurements.

What size should I choose if my measurements are right in the middle between sizes?

If you are unsure, drop us an e-mail – we’ll be glad to advise and assist. The panties shouldn’t cut into your thighs or hips, but they should fit snugly. The materials of our panties are highly elastic and durable. The elastic bands won’t stretch out in the laundry (if anything, they might tighten up a bit, though they’ll quickly expand back as you wear the panties). If you choose a low-waist model, the hip size measurement is key. If you choose a high-waist model, reflect both your waist and hip size. The mid-waist model can be worn both low on the hips or as a hi-cut; its waist hem is more accommodating than that of the high-waist model, and you should again go by your hip size. The mid-waist model is the most versatile, adapting to your needs and complimenting a broad range of body types.

I feel squeamish about the light colors...

The inlay of your panties is ink black, and further below lies the impermeable membrane – there is no need to worry about leakage! If any blood should ever make it to the light parts of the panties, wool-care soap (i.e. lanolin soap or Marseille soap) will take care of it beautifully – tried and tested. What’s more, the fabric is extremely color-fast, so you don’t have to worry about colors rubbing off in the laundry.

I can see light-colored edges around the front and back of the sewn-in pad?

We strive not to use dyed fabric unnecessarily. Because of this, the absorbent part of the panties, including the membrane, are all-naturally colored, which is gentler on you and on the environment. Only the visible parts are made of color fabric, with a view to ease of handling and laundry logistics. Thus, you get the best of both worlds: great-looking panties with a minimum of dye.

Where can I try on the SAYU period panties?

The period panties are available in these stores: PRAGUE Maluna (Tusarova 1384, 170 00 Praha 7-Holešovice) Mokoshop (Na Rozcestí 1161/2, 190 00 Praha 9-Balabenka) Caresse (Korunní 1030, Vinohrady, Praha 2) BRNO Brána ke zdraví (Orlí 17, Brno-střed) Přírodno (Hybešova 726/42, 602 00 Brno-střed-Staré Brno)

Instruction for use

Wash the panties before the first use – by hand or in the washing machine at temperatures of up to 40°C. Make sure the spin cycle speed is set to a maximum of 1,000 rpm! It’s crucial that you use liquid laundry detergent without fabric softener. Washing powder might damage the membrane. Let the panties dry inside-out. After use, rinse the panties in cold water. Wash them using a 40°C washing program and let them dry inside-out. There is no rush; the used panties won’t smell or stain. Simply let them dry, inside-out, after rinsing them by hand. You can then wash them as part of your regular laundry at your convenience. Your panties are again ready to use!

SAYU s.r.o.

IČO: 08320497

DIČ: CZ08320497

+ 420 773 739 774

Červená Skála 338


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SAYU je rodinná firma, která byla založena v roce 2019. Rok předtím jsme se věnovali vývoji technologie, navrhování střihů, hledání kvalitních materiálů a výrobců. Na českém trhu dosud chyběl výběr menstruačních kalhotek, který by splňoval naši představu o kvalitě, designu, provedení a funkčnosti. Stále pracujeme na nových modelech a na zdokonalení naší technologie. Vaše podněty a zpětná vazba nás stále posouvají dál.

Jana, Majda a Pavel