FAQ: Everything you need to know about Modibodi period underwear 

Period underwear has been elevated into the spotlight in the last few years, and they have a lot of us raising an eyebrow and wanting a few answers. We will break down some commonly asked questions about period underwear and discover if they are worth the hype and are they a sustainable alternative to traditional period care.

What is period underwear?

Period undies look like regular underwear; however, they have been designed to wear while you have your period replacing pads, tampons or menstrual cups. Period underwear are absorbent undergarments with extra layers in the crotch region to absorb menstruation blood. Period panties are also reusable. Some women opt to use period underwear for convenience reasons only at some points throughout their period, for example, on lighter flow days or for going to bed as they provide comfortable overnight protection.


How does period underwear work

Each design of period underwear is slightly different, with the same end goal of comfortable absorption in mind. We will break down how Modibodi underwear works as our favourite sustainable option here at Biome. Modibodi stocks various design options, which are differentiated by their level of absorbency. The underwear has three layers top, middle and bottom.
  1. Top layer: The top outer layer is made of merino wool. This fabric is super soft and comfortable against the skin, is naturally antimicrobial and anti-odour, and modibodi also applies an anti-odour treatment so you can feel satisfied with the extra freshness.
  2. Middle layer: The middle layer is made from a quick-drying microfibre that absorbs fluid and odour and can lock it away. It also has antimicrobial technology that fights off bacteria.
  3. Bottom layer: The bottom layer exists for your peace of mind. This breathable bottom layer supplies additional leak-proof protection.

How long can you wear period underwear for?

How long you can wear the underwear before changing them will depend on which level of absorbency you have purchased, which day you are at in your cycle and the intensity of your flow. Some days you may be able to wear a singular pack of underwear for the whole day, and on heavy flow days, you may need several changes. Modibodi's underwear has absorbency equivalence in tampons and recommends when each style of underwear is best to make it easiest to estimate what pair will suit your needs.
  • Super Light: Flow - 5ml = 1 tampon or 1 teaspoon. For - Occasional discharge and drips.
  • Light - Moderate: Flow - 10ml = 2 tampons or 2 teaspoons. For - Light to medium period days, light bladder leaks or heavy discharge. 
  • Moderate - Heavy: Flow - 15ml = 2-3 tampons or 3 teaspoons. For - Medium to heavy period days, heavy discharge & light bladder leaks. 

How many pairs of period underwear do I need?

If it's your first time trialling period underwear and you want to test how they work for you, we recommend buying two pairs for wearing on your lighter days. If you are ready to make the switch, you will usually need one to two pairs per day and one pair for overnight. It will depend on the average length of your period and how often you want to be washing on how many you choose to purchase. We would generally recommend purchasing 5-7 pairs if you plan to be wholly reliant on your period underwear.

Is period underwear safe?

There has been recent discussion around period underwear and the possibility of PFAS (Perfluoroalkyl and Polyfluoroalkyl Substances). PFAS are an artificial group of chemicals that are widely used to make everyday products. For example, they are used to create stick-free cookware and stain-resistant furniture and often in stain or water repellent clothing. Due to the technology of period underwear, it has been questioned whether some underwear brands are using these chemicals. Modibodi has released this statement about PFAS "All Modibodi materials and treatments have been scientifically tested to ensure they comply with global safety standards and requirements. We do not use PFAS or nanotechnology in our garments."

How do I wash period underwear?

Modibodi suggests the following steps to keep your period underwear fresh and clean:

Step 1. Wash your Modibodi before wearing them for the first time. This will activate the technology in the gusset for maximum absorbency.

Step 2. Rinse in cold water after use <30°. Do not soak; rinse until the water runs clear!

Step 3. Cold wash (now or later). In a delicates bag is even better!

Step 4. Hang dry. Reuse. Repeat! Go, you eco-warrior!

Step 5. Hold the fabric softener. This reduces the product's function!

How long does period underwear last?

Period underwear can last two years or longer depending on if they have been cared for properly. Modibodi guarantees the quality and fabric for the first six months, with replacements available if significant faults occur. Outside of this, wear and tear will appear like regular underwear. However, this won't affect the function of the built-in gusset.

Can you wear period underwear swimming?

Due to the fabric makeup, Modibodi does not recommend swimming in their period underwear.

Can period underwear hold urine?

Modibodi's underwear is suitable for light to moderate bladder leaks or light incontinence. In addition, the moisture-wicking and odour-resistant design will help you feel comfortable. We also stock men's leakproof underwear. 

Is period underwear sustainable?

Yes! Period underwear are a sustainable alternative to disposable menstrual products. The average woman will use around 15 000 disposable menstrual products across her lifetime; minimising this plastic packaging and disposable products is a sustainable step forward. So join the movement and shop our range of Modibodi products here to see if you will be converted.


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