Most men’s testicles are about the same size, though it’s common for one to be slightly bigger than the other. It’s also common for one testicle to hang lower than the other one.

The testicles should feel smooth without any lumps or bumps and firm but not hard. You may feel a soft tube at the back of each testicle, which is called the epididymis.

What are testicles?
The testicles are two small oval-shaped organs. They are contained in a man’s scrotum, a sac of skin that hangs below the penis.

The testicles are part of the male reproductive system. They produce sperm and the male sex hormone testosterone.

Examining your testicles
It’s important for men to examine their testicles regularly, about once a month, for any lumps or swellings. Knowing what’s normal for you will help you to notice any changes.

Most lumps in the testicles are harmless. However, in rare cases, a lump can be a sign of testicular cancer. Testicular cancer is most common in younger men and can be successfully treated if diagnosed early.

The best time to examine your testicles is after a warm bath or shower, when the scrotum is relaxed. Hold your scrotum in the palm of your hand and use your fingers and thumb to gently feel each testicle.

If you feel any lumps or swellings in either testicle, or notice any changes in the shape or size of your testicles, see your GP as soon as possible.

What causes lumps and swelling in the testicles?
There are several causes of testicular lumps and swellings:

•varicocele: caused by enlarged veins in the testicles
•hydrocele: a swelling caused by fluid around the testicle
•epididymal cyst: a lump caused by a collection of fluid in the epididymis
•testicular torsion: a sudden painful swelling that occurs when a testicle becomes twisted (this is a medical emergency and requires surgery as soon as possible)
•testicular cancer: an estimated 4 in 100 lumps are cancer, so this is an uncommon cause of lumps