Menstrual panties and technical clothing for periods and other moments of life.

These are washable underwear that absorb menstrual flow, without a tampon or pad. The absorbency is built into the fabric in three layers: a moisture-wicking layer that stays dry against the skin, an absorbent layer that retains the flow and neutralizes odors, and a waterproof membrane that protects clothing. At Smoon, these three materials are assembled seamlessly, resulting in a layer that is twice as thin as average and completely invisible under clothing.

Not if the capacity matches your flow and the size is right. These are the only two causes of leaks. Underwear that is too large creates gaps at the sides, and that is where almost all leaks occur, long before absorbency becomes an issue. Rely on your measurements rather than your usual jeans size, and choose the capacity based on your heaviest days, not your average.

This is the only criterion that can truly make a purchase unsuccessful. For a light flow, at the beginning or end of your period, the equivalent of one tampon is sufficient. For a medium flow, aim for the equivalent of two tampons, providing up to 12 hours of protection. For a heavy flow, four tampons. For a very heavy flow, which may be caused by endometriosis or a copper IUD, you should go up to 150 ml, equivalent to six tampons. Each Smoon product page indicates this capacity.

Three to five, depending on how long your period lasts and how often you do laundry. With fewer than three, you’ll need to do laundry every day. The most practical combination includes two highly absorbent pairs for the first few days and two medium-absorbency pairs for the rest. Many women start with a single pair to try them out, then add more once they’re convinced.

Your usual underwear size, using the size guide provided on each product page. Size charts vary widely from one brand to another, so take your measurements rather than relying on your size from another brand. The Smoon range goes from age 10 for teenagers up to XXL, with a dedicated line for plus sizes.

Between 8 and 12 hours, depending on the model and flow intensity. Smoon microfiber styles provide protection for up to 12 hours, while cotton styles provide protection for up to 8 hours. The best guide is not the clock but how you feel: change when you start to feel uncomfortable. On your heaviest days, changing during the day is normal, just as it is with a disposable product.

Rinse it in cold water immediately after wearing, without soap, until the water runs clear. Hot water sets the blood. Then wash it cold or at 30°C, in the machine on a delicate cycle or by hand. Avoid oily soap and fabric softener, which clog the absorbent membrane and irreversibly reduce its effectiveness. Never put the panties in the tumble dryer; air-drying is sufficient.

An odor that sets in is almost always a sign of a membrane clogged by fabric softener or an overly greasy soap. To clean it, soak it for a few hours in cold water with white vinegar, then wash it normally at 30°C. Rinsing with cold water immediately after wearing it remains the best prevention. If the odor persists after several washes, the membrane is probably at the end of its life.

Several years if properly cared for. Maintenance, more than the initial quality, determines its lifespan. Signs that it’s time to replace it: a noticeable decrease in absorbency, an odor that returns after every wash despite deep cleaning, or fabric that has stretched to the point where it no longer fits properly.

Smoon is a French brand founded in 2018 by Mathilde and Marine, and the first period underwear brand to obtain B Corp certification. Our products are developed in Paris with a textile engineer, using materials from France and Italy, and are OEKO-TEX® STANDARD 100 certified. Our signature remains our seamless technology: no stitching crosses the waterproof membrane, eliminating the usual point of leakage and making the underwear invisible under clothing.