Thanks for your question. A lot of people have questions about their testicles. It is normal for one testicle to be slightly larger than the other, but for the most part they should be approximately the same size. Think of it like your hands, one may be slightly bigger than the other. Also sometimes one testicle will seem to lay flat while your other testicle may be more vertical.
If you notice there is a big difference between the size of your testicles, this may mean something else is going on. Sometimes this can be related to fluid collecting around your testicle making it seem bigger. Other times this can be due to blood vessels around your testicle becoming larger and making your testicle seem bigger. Less commonly, a testicle can become smaller if there is a hormone imbalance or rarely cancer.
If you notice one testicle is much smaller than the other, it’s important to contact your healthcare provider. They will ask you questions about your testicles, any pain in your testicles/penis, any problems peeing, and/or any problems ejaculating. They may order some blood tests and an ultrasound of your testicles to make sure everything looks normal.
Here’s a tip on how to bring it up: One of my testicles seems small, is that okay?