Most people with a penis have two testicles in their scrotum — but some only have one. This is known as monorchism.
Monorchism can be the result of several things. Some people are simply born with just one testicle, while others have one removed for medical reasons.
Read on to learn how having one testicle can impact your fertility, sex drive, and more.
Why does it happen?
Having one testicle is usually the result of an issue during fetal development or surgery.
During late fetal development or shortly after birth, testicles descend from the abdomen into the scrotum. But sometimes, one testicle doesn’t drop into the scrotum. This is called an undescended testicle or cryptorchidism.
If the undescended testicle isn’t found or doesn’t descend, it will gradually shrink.
The procedure to remove a testicle is called orchidectomy.
It’s done for a range of reasons, including:
- Cancer. If you’re diagnosed with testicular cancer, prostate cancer, or breast cancer, removing a testicle may be part of treatment.
- Undescended testicle. If you have an undescended testicle that wasn’t found when you were younger, you may need to have it surgically removed.
- Injury. Injuries to your scrotum can damage one or both of your testicles. If one or both become nonfunctional, you may need surgery.
- Infection. If you have a serious viral or bacterial infection affecting one or both of your testicles, you may need and orchiectomy if antibiotics don’t do the trick.
Testicular regression syndrome
In some cases, an undescended testicle may be the result of testicular regression syndrome. This condition is also known as vanishing testes syndrome.
It involves the “disappearance” of one or both testicles shortly before or after birth. Before birth, the fetus might appear to have two testicles, but they eventually wither away.
Will it affect my sex life?
Usually not. Many people with one testicle have a healthy and active sex life.
A single testicle can produce enough testosterone to fuel your sex drive. This amount of testosterone is also enough for you to get an erection and ejaculate during an orgasm.
However, if you recently lost a testicle, your healthcare provider can give you a some more detailed guidance on what to expect. It may take a bit of time for things to get back to normal.
Can I still have children?
Yes, in most cases, people with one testicle can get someone pregnant. Remember, one testicle can provide enough testosterone for you to get an erection and ejaculate. This is also enough to produce adequate sperm for fertilization.
As long as you’re in good health and don’t have any underlying conditions that could impact your fertility, you should be able to have children.
If you have one testicle and seem to be having fertility issues, consider following up with a healthcare professional. They can do some quick tests using a sperm sample to check for any issues.
Is it linked to any health risks?
Having just one testicle is rarely a risk factor for other health conditions. However, it can lead to some health complications.
- Testicular cancer. People with an undescended testicle have an increased risk of this type of cancer. The cancer can occur on the undescended testicle or the descended one.
- Subfertility. In rare cases, having one testicle can reduce your fertility. Still, this doesn’t mean you can’t have children. You may just have to be a bit more strategic about your approach.
- Hernias. If you have an undescended testicle that hasn’t been removed, it may lead to a hernia in the tissue around your groin that requires surgical treatment.
The bottom line
Several human organs come in pairs — think about your kidneys and lungs. Usually, people can live with just one of these organs while maintaining a healthy, normal life. Testicles are no different.
But it’s still important to regularly follow up with a doctor, especially if you have an undescended testicle. This will help to catch any complications, such as testicular cancer, early on, when they’re easier to treat.
While having one testicle is unlikely to have an impact on your health, it can affect your self-esteem, especially in sexual relationships.
If you feel self-conscious about it, consider a few sessions with a therapist. They can help you work through these feelings and give you tools to help you navigate sexual relationships.
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- Will just one testicle tamper with sex life and fatherhood? (2015).