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Period underwear review

We take a closer look at period underwear to see how it stacks up against pads and tampons. 

two pairs of period underwear
Last updated: 07 December 2020

A revolution is underway in the period product market, with the rise of reusable products such as absorbent underwear. 

Period underwear has been around since 2013, but in recent years these products have shifted from marginal to mainstream. Once sold almost exclusively online, the increasing popularity of period underwear has seen them hit the shelves of supermarkets and department stores, with new brands entering the market. 

With many of us looking for ways to cut down visits to the supermarket, making the switch to reusable menstrual products to avoid running the gauntlet of the sanitary aisle has never been so appealing.

Plus, if you're currently working from home it's the perfect opportunity to try a new menstrual product in the comfort and privacy of your own abode. 

We explain what period undies are and how they work. We also asked five women to trial them to see how they stack up against pads and tampons.

how period underwear works

Period undies have several absorbent and leak-resistant layers in the gusset. Credit:

What are period underpants?

Period underwear are designed to function like normal underwear, but with the ability to absorb menstrual flow, so you can wear them instead of tampons and pads. 

While the exact design varies between products, period undies generally have a moisture wicking top layer, over one or more absorbent layers in the gusset, and a leak-resistant final layer. Some brands also have an extra middle layer designed to neutralise odours.

All period underpants are washable and reusable, making them an eco-friendly alternative to disposable sanitary products.

How long can you wear period undies for?

Period underpants are similar to sanitary pads when it comes to absorbency. How long you can wear a pair for will depend on a number of factors including the heaviness of your flow, the absorbency level of the underwear and whether or not they're being used in conjunction with another product like a tampon or a menstrual cup. 

Your tolerance for feeling a little wet as the underwear begins to reach capacity is also a factor, but due to the material used it's likely period underwear will feel dry and comfortable for longer than a disposable sanitary pad. Unless you have a particularly heavy flow you can usually wear one pair all day, then use a fresh pair overnight.  

It's likely period underwear will feel dry and comfortable for longer than a disposable sanitary pad

Just like sanitary pads, period underwear come in a range of absorbencies. Generally the options start from light or very light (around ½ to one tampon's worth) all the way through to heavy or overnight (up to four tampons' worth). 

But brands measure one tampon's worth differently, which makes it trickier to compare between products.

Thinx 9mL = 1 tampon 

Modibodi 5mL = 1 tampon

Love Luna 5mL = 1 tampon

Bonds  5mL = 1 tampon

AWW 6–7.5mL = 1 tampon

Most brands offer comparisons to other menstrual products such as pads or menstrual cups to help you get an idea of absorbency.

Period underwear brands

As period underpants enter the mainstream, new brands are joining the market including Love Luna, a low-cost option you'll find on shelves at some of the major retailers, and underwear giant Bonds, which launched its Bloody Comfy range earlier this year.

love luna bikini black

Love Luna

Country: Australia

Price range: All three designs are priced at $13.65 on the Love Luna website but instore pricing can range from $13.50 to $23.95 depending on where you shop.

Where to buy: 

Instore: Woolworths, Big W, Target and Best & Less

Online: Love Luna's own site, Birdsnest, Big W, Woolworths, Best & Less, Not Just Bras 


Bikini brief and Midi brief: 2–3 tampons 

Full brief: 3-4 tampons

thinx bikini new moon


Country: USA

Price range: $39.20–$68.59 (depending on exchange rate)

Where to buy:

Buy now

Instore: David Jones and a few select independent retailers (see full list).

Online: Nourished Life and Thinx' own site.


Lightest: ½ a tampon

Light: 1 tampon

Moderate: 2 tampons

Heavy: 3 tampons

Super: 4 tampons

modibodi red hipster bikini starz underwear


Country: Australia

Price range: $23.50-$36

Where to buy:

Buy now

Modibodi doesn't list their stockists (online or instore), but a quick internet search reveals they're stocked by a number of online stores including Nourished Life, Flora and Fauna, Lunette and Every Human as well as Modibodi's own site. They're also stocked in Big W stores on the east coast of Australia.


Super light: ½ a tampon

Light–moderate: 2 tampons

Moderate–heavy: 2–3 tampons

Heavy–overnight: 3–4 tampons.

There's also a 'moisture wicking' option which is designed to absorb sweat only.

Bonds Bloody Comfy Period Undies filler

Credit: Bonds.


Country: Australia

Price range: $19.95–$29.95

Where to buy: 

Buy now

Currently available on the Bonds website and at Woolworths.


Light: 1 tampon

Moderate: 3 tampons

Heavy: 4 tampons

awwa hipster black


Country: New Zealand

Price range: $27.31–$42.37

Where to buy:

Instore: AWWA are stocked in one independent store in WA only.

Online: New Zealand online stores Oh Natural and Health Post (not currently shipping orders to Australia) as well as AWWA's own site.


Light: 1 tampon

Moderate: 2 tampons

Heavy: 3 tampons

Discounted bundles 

Most brands offer bundle deals on their website that let you buy multiple pairs or a whole cycle's worth of underwear at a discounted price. 

It's a good idea to try a single pair to make sure you're happy with the product before committing to a bundle.

user trial pairs

Our triallists were asked to use Modibodi (left) and Thinx underwear.

CHOICE user trial

In 2016, CHOICE asked five women to trial two pairs of Modibodi underwear and one pair of Thinx underwear. 

They were asked to use these for two menstrual cycles, and report back on their experience, comparing it to using pads and tampons. 

They were not comparing between the underwear brands. All products were bought online.

Note: Pads were not popular with our participants before starting the trial – they all rated their satisfaction with them as borderline to very poor. Tampons were more popular, with four participants saying they were very good or good.

The results

Are they reliable?

The underpants were a mixed bag of results. One person said of the absorbent underpants: "I didn't have any leaks and they were pretty comfortable (I used them without a cup or tampon)."

Two out of five trialists experienced a small amount of leakage with the underpants and one commented: "They are great as a backup but I would never rely on them as a first line of defence!"

Some trialists combined the undies with a menstrual cup, with one saying, "It was nice to know there was another barrier of protection."

The underpants were also embraced as a precautionary measure, with comments including, "They're good to wear if you're expecting your period" and "They were a particular success on those last few days that don't warrant a tampon."

Are they comfortable and easy to use?

Again, there were both positive and negative responses. Some loved the texture, with comments including: "The period underpants were much more comfortable than a pad," and "I never really liked using pads but the underpants pleasantly surprised me."

However, three commented that if they caught some heavy flow, it wasn't very comfortable keeping them on all day, with one describing the feeling as "soggy".

Are they easy to clean?

Washing the underpants was straightforward but they took two days to dry, due to their absorbency, and they can't be put in a dryer. 

Users shouldn't expect to wear one pair more than once in three days.

Overall thoughts

At the end of the trial, three out of five trialists said they'd continue to use period underpants and that they'd recommend them to their friends.

All of the trialists agreed period underpants should be available in pharmacies and other places that sell feminine hygiene products.

Will period undies save me money?

The sanitary items sector in Australia is worth $2.1 billion, although this figure has been steadily declining over the past five years. Prior to January 2019, 10% GST was applied to menstrual products, but substantial campaigning led to the removal of the tax, causing the retail price of menstrual products (including period underwear) to drop by approximately 9.1%.

While the removal of the "tampon tax" has slightly decreased the lifetime cost of disposable menstrual products, an individual exclusively using tampons may still spend around $55 to $125 a year.

One pair of Modibodi underpants will set you back between $23.50 and $36 and, according to the manufacturer, will last up to two years. A spokesperson from Love Luna ($13.65 for one pair) says their products will last for 12–18 months if all care instructions are followed carefully. The Thinx underpants cost $39.20–$68.59 depending on the exchange rate, plus shipping. Four out of five of our trialists thought they paid too much for the disposable options.

CHOICE also heard from one user (who wasn't part of the trial) that their Modibodi underpants began to fray after six months. The company says it will guarantee the quality and fabrics for up to six months. 

There's no set formula as to how many pairs a person will need because it depends upon whether they're paired with other products, and how heavy the menstrual flow is. Given they can take two days to dry, you could require six pairs over three days and nights if using them alone. 

Modibodi CEO Kristy Chong says the initial investment of seven pairs of period underwear (which she recommends is sufficient for many customers) would pay itself off in roughly two years in terms of savings on disposable products.  

Are period underpants suitable for tween girls? 

For teens and tweens only just embarking on a lifetime of menstrual cycles, period underpants can offer a comfortable and confidence-building alternative to pads or tampons.

'Knowing your cycle' isn't easy in the early months and years, and unexpected bleeding or leakage can cause anxiety. And judging by the lively conversations on this topic on social media, many mums are just as anxious for their daughters.

Red by Modibodi

Modibodi offers a dedicated youth range called Red by Modibodi.

Sizes are for ages 8–10, 10–12, 12–14 and 14–16. Currently, all teen underwear is moderate-heavy absorbency with a choice of bikini or boyshort and wide range of prints.

Thinx (BTWN)

Thinx (BTWN) comes in US sizes 9–10, 11–12, 13–14 and 15–16 with a choice of three cuts and a range of colours. All tween underwear is suitable for a heavy flow.


AWWA offers a teen brief in sizes 8–10, 10–12 and 12–14 in light, moderate or heavy absorbency with a choice of two neutral colours.

modibodi swim bikini bottom black

Modibodi's swimwear bikini pants. Credit:

How do period swimmers work?

Period swimmers have a moisture-wicking absorbent top layer and a highly water-repellent, fast-drying outer layer. They should be used as a backup with a tampon or cup for heavy or moderate days to prevent leaks or as a standalone product for light days. They can also be worn to prevent getting caught out when you're expecting your period.

Modibodi stocks a one piece and a bikini bottom in both their adult and teen sizes. AWWA offers a bikini set for both adults and teens. 

Modibodi claims its swimmers can hold up to two tampons' worth.AWWA claims their swimmers can hold up to one tampon's worth of liquid.

Are period undies safer than tampons and pads?

Tampons can be made of cotton, rayon, or blends of these, and may also contain synthetic fibres. Sanitary pads can be made of cotton, plastics and other synthetic or chemical components. 

There is no requirement for manufacturers to disclose the substances in these products. In addition, there has been little research into the health effects of substances in tampons and pads (such as deodorisers, plasticisers, fragrances, pesticide residues and dioxins). 

Vulval and vaginal tissue is highly absorptive and some groups fear that undisclosed toxins in tampons or pads may enter and accumulate in the body. 

Period underwear is usually made from a mixture of natural materials like cotton, bamboo or merino wool and synthetic materials like nylon, elastane, spandex and polyester. Just like other clothing, period underwear can contain potentially harmful chemicals and need to be washed according to instructions.

Earlier this year, Thinx made headlines after a nuclear scientist reportedly conducted independent testing on two pairs of their underwear and found high levels of a group of chemicals called PFAS, which have been shown to harm human health. The company maintains that its own testing has never detected any traces of PFAS or other toxic chemicals and their test results are publicly available on their website. 

Just like other clothing, period underwear can contain potentially harmful chemicals and need to be washed according to instructions

Royal Australian and New Zealand College of Obstetricians and Gynaecologists spokeswoman Dr Talat Uppal says she doesn't generally recommend period underwear.

"While period underwear have economic and environmental advantages, disposable pads and tampons have undergone extensive pre-market testing, making them a safer option."

"I also worry about the reuse of period underwear compromising cleanliness and increasing the potential risk of infection."

If patients do want to use reusable menstrual products, she recommends the menstrual cup as the best option as there are currently no safety-based concerns (compared to single-use sanitary products), they are generally cost effective and an environment friendly option.

What about reusable pads and tampons?

Reusable pads

Reusable pads usually consist of natural fibres like cotton or hemp with a leak-proof outer layer. They have wings with snaps which fasten around the gusset of your underwear to keep the pad in place. Just like their disposable counterparts, reusable pads come in different absorbencies, shapes and sizes to suit various flows and underwear types. 

Reusable pads are a bit more fiddly than period underwear, but they are easier to change on the go and less bulky to carry around once removed. They're also generally cheaper with prices ranging from about $10 to $30.

Reusable tampons

Although not widely available, reusable knitted, crocheted or fabric tampons are sold by a handful of online sellers, while some sites offer DIY tutorials. 

Uppal says these products are not regulated and there is little research around their safety.

"Wool or crochet material has the tendency to shed at a microscopic level and there is a higher chance that these fibres might cling to the vaginal walls, increasing the risk of toxic shock syndrome.

"Although regular tampons are not sterile, they are clean-packed, unlike DIY products which potentially carry a higher risk of infection."

How bad are tampons and pads for the environment?

Period underpants have minimal impact on the environment compared to tampons and sanitary pads. 

Four out of five of the trial participants reported they were concerned about the waste and environmental impact of disposable pads and tampons.

We estimate the average woman uses about 11,000 pads or tampons over her lifetime, depending on individual needs.

The production of sanitary pads involves oil extraction, processing and production of low-density polyethylene (LDPE), with the associated CO2 emissions. 

The average woman uses about 11,000 pads or tampons over her lifetime

Tampons don't contain plastics except in their wrapping, but involve heavy resource use through the agricultural processes of cotton cultivation, especially fertilisers, pesticides and water use.

After the impacts of production, tampons and pads must be transported and disposed of in landfill. It's been estimated that each pad will take 500–800 years to biodegrade, while one source says tampons may take six months to biodegrade in landfill.

Alarmingly, research in the UK found that nearly half of British women flush their sanitary items down the toilet, believing this is the normal method of disposal.

Flushing tampons, pads and their wrappers down the toilet causes blockages of pipes inside private property and throughout sewage systems.

It's been estimated that each pad will take 500–800 years to biodegrade, while one source says tampons may take six months

Sydney Water operations manager Darren Cash says they remove over 500 tonnes of non-degradable material (including wet wipes, tissues and menstrual products) each year from the wastewater network, at an annual cost of around $8 million. 

But the costs are not confined to the water treatment companies. "Individual home owners may also be out of pocket with expensive plumbing bills," says Cash. "One Sydney resident had a plumbing bill of $16,000 to repair a problem caused by flushing wet wipes." 

While wet wipes are the main cause of blockages (especially in light of the current toilet paper shortages), disposable sanitary items like pads and tampons also contribute to the problem. 

We've previously investigated the problems with supposedly "flushable" wipes, and even awarded Kleenex a Shonky for them.

We care about accuracy. See something that's not quite right in this article? Let us know or read more about fact-checking at CHOICE