Just to be clear, generally speaking, small testicles are usually not a big health problem. Testicles come in all shapes and sizes. Whether lopsided or symmetrical, they’re all unique. But some men may worry about their size – are they too large or maybe too small?

One way to assess testicle size is to measure the length from top to bottom. On average, this length is between 4.5 to 5.1 centimeters.

Dr. David Samadi, Director of Men’s Health at St. Francis Hospital in Roslyn, New York says that men with smaller-than-average testicles often worry if they are normal while men with normal to large sized testicles tend to have fewer concerns.

‘From my experience as a urologist, small testicles generally present few problems. However, if they have become smaller than normal over time, then it wouldn’t hurt to ask your doctor why this may be.’

Potential causes of small testicles

Here’s a look at potential causes of small testicles and how to treat it.

Low testosterone

It has been found that men who notice their testicles have shrunk could indicate low testosterone.
‘While it is true that some men with low testosterone may notice a smaller size of their testicles, it’s not true for all men,’ says Dr. Samadi. ‘You have to look at the entire picture of a man and what other symptoms he may be experiencing.’

Other symptoms of low testosterone besides small testicles can include: a low sex drive; difficulty achieving and maintaining an erection; fatigue; mood changes and irritability; depression; and a loss of muscle mass.

Dr. Samadi says low testosterone in any man needs to be addressed. ’Men experiencing symptoms of low testosterone should contact their primary care physician as soon as possible to get tested and then treated for it. Doing so helps men avoid many of the health issues associated with this common condition.’


Varicoceles are veins that become enlarged inside the scrotum of men – comparable to developing a varicose vein in a leg. Some men with a varicocele may have issues with fertility as up to 40% of men with infertility have varicoceles. Occasionally, a man with varicoceles will notice a change in the size of their testicles; one testicle may be smaller than the other or both have shrunk.

Dr. Samadi says that the treatment for varicoceles is usually surgery. ‘After surgery is performed, in most cases the testicles return to their normal size.’

Congenital disorders

Sometimes a baby boy may be born with a congenital disorder that can cause testicles to be small. Klinefelter Syndrome is one such disorder.

Klinefelter syndrome is the result of one extra X chromosome (written as XXY) in baby boys and is estimated to occur in about 1 out of every 500-1,000 newborn males. Exact causes of it are not known but the error producing the extra chromosome happens at random and is not hereditary. The only suggested increased risk is that it occurs slightly higher in women who have pregnancies after age 35.

Some physical symptoms males with Klinefelter Syndrome include: slower in developing motor skills, coordination, speed, and muscle strength; fatter around the belly; clumsier; smaller testes and penis; breast growth (affects about one-third of teens); less facial and body hair; reduced muscle tone; and narrower shoulders and wider hips.

‘While there is no cure for Klinefelter Syndrome, the symptoms can be treated successfully helping to minimise the impact of the condition,’ says Dr. Samadi.

‘About half of all males with Klinefelter Syndrome have low testosterone levels which can be treated by taking supplemental testosterone.

‘Working closely with an endocrinologist, a doctor who specialises in hormones and will closely follow a man’s use of testosterone therapy, is the best way to treat this condition.’

Testicular atrophy

Atrophy means to shrivel or waste away. In regards to testicular atrophy, the testicles have become smaller. Sometimes a surgery to repair an inguinal hernia can be a cause or men who’ve had repeated inguinal hernia repairs have a higher risk of testicular atrophy. Some other causes include aging, sexually transmitted diseases, mumps, and cirrhosis due to alcohol consumption.

Depending on the cause of testicular atrophy will determine the treatment. Any man with concerns of testicular atrophy for an unknown reason should seek the advice of his doctor.

‘The main message for all men with concerns of testicular size is to ask their doctor about it. Likely, there is no problem but why worry unnecessarily,’ saysd Dr. Samadi. ‘Ask and if it’s treatable, do so. If nothing wrong is found remember all men come in different sizes so whether large or small, as long as it works, that’s all that matters’

David B. Samadi, MD, Urologic Oncology Expert and Robotic Surgeon located at 485 Madison Avenue on the 21st floor, New York, NY.