If you and your partner are trying to conceive, your underwear drawer probably isn’t the first place you’d look for answers. But research consistently shows that scrotal temperature directly affects sperm production, and what you wear down there plays a bigger role than most blokes realise. Choosing the best men’s underwear for fertility can genuinely support sperm health, no gimmicks, just science-backed design choices that keep things cool, supported, and comfortable.
The key factors? Fabric breathability, airflow around the groin, and whether your underwear holds everything in a tight squeeze or gives your boys room to breathe. Tight synthetic briefs trap heat. Loose boxers offer zero support. The sweet spot sits somewhere in between, and that’s exactly the space we designed SLY Collective’s bamboo pouch underwear to fill. Our temperature-regulating bamboo fabric and anatomical pouch keep the testes lifted, separated, and naturally cool without sacrificing support.
We’ve tested, researched, and compared options across the Australian market to put together this list of seven underwear picks that actually support fertility. Each recommendation is evaluated on material, design, breathability, and real-world comfort, so you can make a confident switch while you and your partner focus on what matters most.
1. SLY Collective bamboo pouch boxer briefs
SLY Collective’s bamboo pouch boxer briefs top this list of the best mens underwear for fertility because they tick every key criteria: cooling fabric, anatomical support, and chafe-free comfort. They’re designed in Australia with testicular health built into the cut from the start.
Why it helps fertility
Scrotal temperature needs to stay below core body temperature for optimal sperm production. SLY Collective’s bamboo fabric and separate ball pouch work together to keep heat down and airflow up, directly supporting the conditions your body needs to produce healthy sperm.
Studies show that men who switch to supportive, breathable underwear for 17 weeks see measurable improvements in sperm concentration compared to those wearing tight synthetic styles.
What makes the pouch design different
The built-in inner pouch physically separates and lifts the testes away from your thighs, stopping skin-on-skin contact before it starts. Unlike standard boxer briefs that press everything flat, this design gives your anatomy its own structured space to sit naturally and stay cool.
Breathability and temperature control
Bamboo fabric outperforms cotton and synthetic blends when it comes to airflow. It wicks moisture, resists odour, and regulates temperature throughout the day, whether you’re in a long work meeting, training, or sweating through an Australian summer.
Comfort and chafe prevention for active days
The longer leg design prevents ride-up, so you’re not adjusting constantly. Chafe-free comfort comes down to the cut staying put, meaning friction never builds up across the inner thighs during active days.
Who it suits best
These suit men dealing with daily chafing, overheating, or discomfort who want underwear that actively supports fertility. They’re also a strong pick for anyone managing varicocele or recovering post-vasectomy.
Downsides to know before you buy
Pricing sits above mass-market brands, so the upfront cost is higher than supermarket packs. Sizing can also run slightly generous, so check the size guide before ordering.
Price in Australia
Pairs start at around $39.95 AUD, with bundle deals available that reduce the per-pair cost.
Where to buy in Australia
Order directly from slycollective.com, which offers free shipping on orders over $100 within Australia and free size exchanges if the fit needs adjusting.
Fertility checklist we used to rank these picks
Every pick on this list was assessed against five criteria: fabric breathability, anatomical support, moisture management, everyday comfort, and whether the design actively reduces scrotal heat. SLY Collective scored highest across all five categories.
2. Mr Fertyl fertility boxer
Mr Fertyl is a brand built specifically around male fertility and scrotal health, making it one of the few underwear brands that puts sperm health at the centre of its design brief rather than treating it as an afterthought.
Why it helps fertility
Mr Fertyl’s wider pouch cut keeps the testes away from thigh heat and body warmth, directly targeting the scrotal temperature reduction that supports healthy sperm production during conception attempts.
How the fertility-first cut manages heat
The boxer’s relaxed, extended pouch creates airspace around the scrotum, reducing trapped heat without sacrificing the structural support that keeps everything in place throughout the day.
Research links elevated scrotal temperature to reduced sperm count and motility, making airflow design a practical fertility tool rather than a marketing angle.
Fabric and dye safety considerations
Mr Fertyl uses skin-safe, low-irritant dyes alongside breathable fabric blends, which matters because synthetic irritants near sensitive skin can cause localised inflammation and discomfort over time.
Support level and everyday comfort
The cut balances freedom of movement with enough structure to stay in place, making it comfortable for desk work and light activity without bunching or riding up during longer days.
Who it suits best
These suit men specifically focused on fertility outcomes who want a purpose-built option and are happy to shop outside mainstream brands for a more targeted solution.
Downsides to know before you buy
Availability in Australia is limited, and the range of styles and colour options is narrower than more established brands on this list.
Price in Australia
Pairs typically retail at around $35 to $45 AUD depending on the style selected.
Where to buy in Australia
Order through the Mr Fertyl website directly, as local Australian stockists are few and stock levels vary seasonally.
3. Step One bamboo boxer briefs
Step One is an Australian brand that has built a strong following for its longer leg, chafe-free boxer briefs, making it a practical option worth considering when you’re looking for the best mens underwear for fertility without going outside mainstream retail.
Why it helps fertility
Step One’s bamboo fabric keeps scrotal temperature lower than cotton or synthetic blends by wicking moisture and allowing airflow to move freely around the groin. Cooler, drier conditions give your body the environment it needs to produce and maintain healthy sperm.
Scrotal temperature just one to two degrees above the optimal range can reduce sperm motility and concentration, making breathable fabric a genuine fertility consideration.
Cooling and anti-chafe features
The longer leg design is central to Step One’s anti-chafe claim, and it delivers. By keeping fabric between your thighs throughout the day, it prevents the friction buildup that causes discomfort during long workdays or active sessions.
Fabric and breathability
Step One uses bamboo viscose across its boxer brief range, which handles sweat well and stays soft against sensitive skin. The fabric breathes noticeably better than polyester blends and resists odour through extended wear.
Fit, leg length, and ride-up control
The longer leg cut stays in place without rolling or bunching, which is the core design strength. Sizing runs fairly true, though men with shorter inseams may find the leg length slightly long.
Who it suits best
These suit men who want chafe-free everyday comfort with genuine breathability and prefer buying from an established Australian brand with easy local returns.
Downsides to know before you buy
Step One does not offer a dedicated anatomical pouch, so support is standard rather than structured. If active scrotal separation and lift matter to you, this design won’t match a purpose-built pouch brief.
Price in Australia
Pairs retail at around $34.99 AUD, with multi-pack bundles available through their website.
Where to buy in Australia
You can order directly from the Step One website, which stocks the full range and ships within Australia.
4. Boody men’s boxer briefs
Boody is an Australian brand focused on sustainable bamboo basics, and their men’s boxer briefs offer breathable, soft comfort that supports scrotal temperature management without the complexity of a purpose-built fertility design.
Why it helps fertility
Boody’s bamboo viscose fabric wicks moisture and allows airflow around the groin, helping keep scrotal temperature lower than cotton or synthetic blends. Cooler, drier conditions support the environment your body needs for healthy sperm production.
Scrotal temperature even slightly above optimal can reduce both sperm concentration and motility, making fabric choice a practical fertility consideration.
Softness, airflow, and moisture management
The bamboo construction moves sweat away from your skin and keeps the fabric feeling light throughout the day. Airflow is noticeably better than polyester options, and the material stays soft against sensitive skin through extended wear.
Waistband feel and all-day comfort
Boody uses a flat, tag-free waistband that does not dig in or restrict blood flow. For men who spend long hours at a desk or on their feet, this keeps comfort consistent across a full day.
Fit and sizing notes
The fit runs true to size for most builds. The cut is standard without a structured seat or thigh, so check the size chart if you sit between sizes before ordering.
Who it suits best
These suit men who want affordable bamboo underwear with genuine breathability and prefer buying from a well-known Australian brand available in mainstream retail.
Downsides to know before you buy
Boody offers no anatomical pouch, so you won’t get structured scrotal separation or lift. If active support matters for your search for the best mens underwear for fertility, a purpose-built pouch design will serve you better.
Price in Australia
Pairs retail at around $29.95 AUD, making Boody one of the more affordable bamboo options on this list.
Where to buy in Australia
You can buy directly from the Boody website or through major Australian retailers like Myer and David Jones.
5. Bonds cotton woven boxers
Bonds is one of Australia’s most recognised underwear brands, and their cotton woven boxers offer a simple, accessible option for men who want loose-fitting breathability without investing in a premium fabric upgrade.
Why it helps fertility
The loose woven cut keeps the testes away from direct thigh contact, reducing heat build-up throughout the day. For men searching for the best mens underwear for fertility on a budget, Bonds woven boxers offer a practical starting point backed by decades of consistent availability in Australian retail.
Why loose woven boxers stay cooler
Woven cotton doesn’t cling to your skin the way a knit fabric does. The open construction allows air to circulate freely around the groin, helping to keep scrotal temperature lower during extended wear.
Research shows that switching from tight briefs to looser boxer styles reduces mean scrotal temperature, which is directly linked to improvements in sperm concentration over time.
When woven boxers work better than knits
Woven boxers work best during low-activity days, like office work or relaxed weekends, when you don’t need structured support. Knit boxer briefs suit active movement better, but for sedentary hours, a woven cut offers more passive airflow.
Fit tips to avoid accidental tightness
Size up if you’re between sizes, as woven cotton shrinks slightly after washing. Avoid pulling the waistband too snug, since compression at the waist restricts airflow just as much as a tight leg opening.
Who it suits best
These suit men who want an affordable, no-fuss option and prioritise maximum looseness over structured support or premium fabric performance.
Downsides to know before you buy
Bonds woven boxers offer zero anatomical support, so they’re not suited to active days or men who need structured lift. Pure cotton also retains moisture longer than bamboo, which can work against you during warmer months.
Price in Australia
Pairs retail at around $14 to $20 AUD, often available in multipacks at a lower per-pair cost.
Where to buy in Australia
You can buy from the Bonds website or pick them up at major Australian retailers including Target, Big W, and Myer.
6. Calvin Klein cotton boxers
Calvin Klein’s cotton boxer range is widely available across Australia and offers a familiar, accessible option for men who want reliable breathability from a trusted international brand.
Why it helps fertility
Cotton naturally breathes better than synthetic fabrics, making CK boxers a reasonable choice if you’re looking for the best mens underwear for fertility without stepping outside mainstream retail. The looser boxer cut keeps the testes away from direct thigh contact, supporting lower scrotal temperatures throughout the day.
Research shows that loose-fitting cotton boxers reduce mean scrotal temperature compared to tight synthetic briefs, which directly supports healthier sperm production conditions.
Fabric quality and breathability
CK uses combed cotton across most of its boxer range, which is softer and more breathable than standard cotton. The weave manages light moisture reasonably well, though it doesn’t wick as efficiently as bamboo fabrics during warmer conditions.
Fit differences across CK boxer ranges
Calvin Klein sells both woven boxers and knit boxer briefs, and the difference matters for fertility. The woven cut offers more passive airflow, while the knit styles can compress more than you’d want for extended daily wear.
How to avoid tight waistbands and leg openings
Size up one size if you’re between sizes, as CK cotton can shrink slightly after washing. Check that the waistband sits flat without pulling snug against your lower abdomen.
Who it suits best
These suit men who want easy access to a breathable cotton option through mainstream Australian retail without committing to a premium brand.
Downsides to know before you buy
There is no anatomical pouch, and cotton retains moisture longer than bamboo, which works against you during humid Australian summers.
Price in Australia
Pairs retail at around $25 to $40 AUD depending on the style and retailer.
Where to buy in Australia
You can buy from Calvin Klein’s Australian website or through major retailers including David Jones and Myer.
7. SAXX DropTemp cooling boxer briefs
SAXX is a Canadian brand widely available across Australian retailers, and their DropTemp cooling boxer briefs stand out for combining an anatomical pouch with active cooling technology, making them a strong contender for the best mens underwear for fertility.
Cooling tech and airflow design
SAXX’s DropTemp fabric uses a cooling yarn that draws heat away from your skin on contact. The construction targets the groin specifically, pulling warmth away from the scrotum to help maintain a lower scrotal temperature throughout the day.
Research consistently links elevated scrotal temperature to reduced sperm count and motility, making active heat management a genuine fertility advantage rather than a marketing claim.
Support without overheating
The BallPark Pouch lifts and separates the testes from your thighs, providing structured support without creating the trapped heat that tight conventional briefs produce. You get anatomical separation and lift without the thermal cost.
Fabric blend and moisture control
The DropTemp range uses a polyester-based cooling blend rather than natural fibre. It wicks moisture effectively, but the synthetic construction breathes less passively than bamboo fabrics across a full day of wear.
Who it suits best
These suit men who want active cooling technology paired with a proper pouch design and are comfortable with a synthetic fabric blend.
Downsides to know before you buy
The synthetic fabric does not breathe as naturally as bamboo, and some men find it less comfortable against sensitive skin over long periods.
Price in Australia
Pairs retail at around $49.95 to $59.95 AUD depending on the retailer.
Where to buy in Australia
You can buy through SAXX’s Australian website or through major sporting and lifestyle retailers including Rebel Sport.
Next steps
Choosing the best mens underwear for fertility is one of the simplest, most practical changes you can make while trying to conceive. Every pick on this list reduces scrotal heat in some way, but the options with a dedicated anatomical pouch and breathable natural fabric give you the most direct combination of temperature control, support, and all-day comfort.
If you want a starting point that covers every fertility-relevant factor in one design, SLY Collective’s bamboo pouch boxer briefs are built precisely for that. Bamboo fabric, structured lift, and a chafe-free cut work together to keep conditions consistently cool without sacrificing comfort during active or long days. Your first pair comes with a comfort guarantee, so there is no risk in making the switch.
Browse the full range and find your size at SLY Collective’s men’s pouch underwear.