How to take care of your period swimwear: 5 simple steps

5 simple ways to take care of your swimwear

When you invest in period swimwear, you want them to last a long time and that's normal!

We chose them for their comfort and their ecological alternative to disposable protection while enjoying a swim, but we don't want to worry about their maintenance!

This is a good thing because you will see that washing is not more complicated than throwing away. Period swimwear are functional and the textile materials that make them up have technological properties. But once you know the theory, nothing is more basic than including them in your daily laundry. Pre-washing, washing, drying, taking care of your period swimwear is a matter of a few simple gestures.

UndieStar explains everything and answers your questions.


Knowing their composition

The washable protection UndieStar are technological underwear. Indeed, they combine no less than 4 levels of protection:

- 1 layer of soft and anti-moisture fabric in contact with the skin

-1 anti-odor layer

- 1 layer of ultra absorbent material

- 1 anti-leakage, waterproof or rather waterproof-breathable layer (otherwise beware of perspiration!).

Avoid products and actions that are harmful to their life span.

These fabrics require some care to maintain their optimum level of efficiency. Washing agents that are too "greasy" considerably reduce absorption and anti-odour power.

Certain detergents that are too aggressive and the tumble dryer destroy the anti-leak properties. Water that is too hot has the same effect and contributes to fixing blood stains to fabrics.

This is why it is recommended to wash your menstrual swimsuit cold or at 30°C maximum, with a soft detergent, and to dry them, at best, in the open air, at worst, on a warm towel dryer.

How to remove blood

Blood is an organic material that coagulates, that is to say that the platelets contained in it clump together to prevent hemorrhaging in case of injury. This action is increased tenfold by heat. Thus, by rinsing a bloodstain with hot water, it will coagulate and adhere to the textile. This is why pre-washing / rinsing with cold water, even very cold, is your best ally for your menstrual swimsuit.

But some small tricks also exist in the event of spot of dried blood:

  • The salt: deposit it directly on the slightly wet spot in thick layer;
  • The physiological serum: soak a clean rag of it and rub the spot;
  • Aspirin tablet: soak the damaged textile part in a bowl of water and add an aspirin tablet. It is a powerful anticoagulant (be careful never to swallow it during your period!).
  • Ox gall soap: this powerful natural stain remover is used before washing. It is very effective for all stains of organic origin, especially blood.

Don't panic at the slightest loss of performance

Your period swimwear don't absorb anymore? Don't panic! It is not irreparable, it is often the result of poor maintenance or several years of use. It is the sign that the fibers are loaded with cause (of limestone, saponin...). A small operation exists to give them back all their efficiency: the deep cleaning (or less nicely named "scouring"). Just soak them for a few hours in a mixture of vinegar and water (5 cl per liter). And in case of annoying smell, add a level tablespoon of baking soda. Be careful not to repeat this procedure too often: the vinegar would "attack" the waterproof membrane of your menstrual swimwear. Don't worry! This rarely happens.

It's easier and faster than using disposable protection

Investing in menstrual swimsuit certainly requires a little time at the beginning (to choose them, to prepare them before their first use...) but you keep them during 7 years!

The time saving is considerable because the gestures to maintain them affect less, each month, your timetable, than to :

  • Going back to buy disposable pads
  • Looking for the right section in your store
  • Comparing brands and their prices
  • Putting them away when you get home
  • Fill the trash can with the used ones
  • Throw them away and clean the garbage can; solve the problems caused by the chemicals they contain: irritation, fungus, etc.


Why cold water for pre-washing?

Cold water avoids the coagulation of blood and prevents it from adhering irreparably to the absorbent fabric.

Why wash your period swimsuit at 30°C maximum?

We have in mind that the hotter the water, the better it washes. But this is a misconception about period swimwear! Heat above body temperature irremediably fixes blood stains and, above all, deteriorates the impermeability of "barrier" fabrics. The sanitization of your swimsuit depends above all on the detergent used and the quality of the washing in the machine (to do this, make sure that it is only three-quarters full).

Why choose a "delicate" program?

It is especially the spinning speed that can be harmful in the long run. Of course, spinning at 1200 rpm will allow faster drying. You can use it from time to time, but it could expel a certain amount of fibers and therefore make your swimsuit less absorbent. Not to mention that the friction due to the speed gives off heat that is harmful to waterproof-breathable fabrics.

Why not put my period swimwear in the dryer?

The tumble dryer is very practical... Yes but here it is... it can damage your bottom period swimwear and on several levels:

it is a real "eater" of textile fibers;
it deteriorates the elastics;
it destroys the waterproofness of the fabrics from the first use.
Therefore, do not use it!

What detergents should I use for my period swimwear?

All mild detergents, if possible ecological and preferably in powder form.

Why should I use a powder detergent for my period swimsuit?

All liquid detergents contain water in addition to surfactants (detergent products). Preservatives are therefore added to prevent the mixture from going mouldy. These viscosifying, opacifying, anti-foaming products load the absorbent fibers and can reduce the absorption efficiency over time.

Can I use bleach to bleach my menstrual swimwear?

Absolutely not! Bleach is not only a bleaching agent, it is also an oxidizing agent that would permanently destroy waterproof fabrics.

How to remove a stubborn bloodstain?

For a recent stain, as we have seen, nothing better than cold water! But for a dried blood stain, on a light fabric in particular, we have a little trick: add a tablet of aspirin in your machine! Yes, aspirin is an anticoagulant. We know that because it is not recommended as a medication for menstrual pain... But in the machine, nothing to worry about!

Can I use a softener to make my period swimwear less rough?

Softeners load the absorbent fibers. When swimwear becomes rough, it is probably because the washing water was too hard. To remedy this, add half a glass of white vinegar (or spirit vinegar) to the machine at the beginning of the wash and that's it! But be careful, this manipulation is not to be done systematically because vinegar is acid and thus "attacks" waterproof fabrics.

How can I make my period swimsuit smell good?

A menstrual panty that smells bad is a panty that contains bacteria. It is thus the sign of a bad maintenance. For that a small handling of "cleaning" is essential: To make soak a few hours its swimwear in water with white vinegar (5cl for 1 liter) and a soupspoon of bicarbonate of soda: vinegar cleanses and returns their absorption to the fibres; the bicarbonate is an odour absorber.

My period swimsuit are less absorbent, what can I do?

Without necessarily smelling bad, a menstrual panty can simply become less absorbent with time. There still, the cause is the bad maintenance and the clogging of fibres. It is the sign that it is time to "clean" its swimwear: to make soak them a few hours in a mixture of water + a little vinegar (10 cl glass for 2 liters of water approximately).

Can I use Marseille soap to wash my menstrual swimsuit ?

The authentic Marseille soap is an excellent natural detergent. It is composed of soda (at the origin of saponification), sea salt, essential oils, water and vegetable oils. The latter may nevertheless grease the absorbent fibers. If your underwear becomes less efficient, be aware that this may be the cause and prefer an ecological washing powder.

Does putting my period bikini in a net protect them?

Yes, it does! However, be careful not to put too much in the net, as this would prevent the laundry from being properly mixed in the machine, which is the key to effective washing!

How do I organize my laundry so that I never run out of period bikini?

You can wash your period swimsuit with your regular laundry at 30°C. But it is quite possible to wash only your swimsuit in the washing machine: the current washing machines are very often equipped with the automatic variable capacity.


  • Wash your swimwear before using them.
  • Rinse them in cold water before washing.
  • Wash them in the washing machine on a delicate program at 30°C maximum without aggressive detergents.
  • Dry them in the open air; never use a tumble dryer!
  • If your swimwear are less absorbent or smell bad, clean them with a little household vinegar and baking soda.