Trying to Get Pregnant?

Sperm count and sperm quality matter when trying to conceive. Boost male fertility the natural way.

Underdog Male Fertility Cooling Kit on

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Sitting Damages Sperm

Graph showing lower sperm count and decreased motility from testicular overheat.

Introducing The Underdog

The Underdog fertility cooling ice pack in sleeve.

The Underdog Prevents Overheating

Graph showing results of cooling testicles for improving sperm count using Underdog ice pack.


Easy to Use

Small and discreet

Slips easily between the seat and pants

No special underwear

No condensation

Improve Fertility Naturally

Very mild & gentle cooling

Non-invasive and no-risk

Use before natural conception

Use before IVF to improve the odds

Soft and Comfortable

Comfortable padded sleeve

Ergonomic wedge shape

Fits all body types

Better Sperm, Better Outcomes.

Are you ready to get started?


Promising enough that we are offering our men the option of using these devices ‎as a part of their therapy for infertility.

Dr. K. J.

Healthy sperm are very sensitive to overheating. The Underdog keeps the testes at the perfect temperature. Wonderful and discrete. Highly recommended.

Dr. C. L.

Quality build and packaging. The ice pack is comfortable enough to use for a few hours straight while keeping its "cool", and inconspicuous enough for the office.


It's my secret weapon that I like to tell patients about. Nice and comfortable. It feels great. If you're a man, you know you need this. If you're a woman, your partner's sperm will thank you for it.

Dr. M. S.

It cools down my balls and raises sperm counts. Would highly recommend to those who want to conceive.


Pretty impressed with this product. First, it comes with two ice packs which is great for a long day. Next, it feels very comfortable when using. Temperature is perfect. Not too cold or hot.


Expert Recommendation

Fertility expert Dr. Charlene Lincoln recommends using The Underdog when trying to conceive.

The Underdog Mission

Underdog Fertility was founded by three professionals touched by infertility who care deeply about helping others start a family.  

With the help of our medical advisory team, we're on a mission to create practical tools that improve men's health. 

Life is short, so let's get started!

The Underdog is protected by US and international utility patents pending.

Underdog, The Underdog, Underdog Fertility and the Dogface Logo are trademarks of Underdog Fertility. 

Note: The Underdog is a general wellness device, and is not intended for use in the the cure, mitigation, treatment, or prevention of underlying disease or medical conditions.