Anabolic Steroids & Testicular Atrophy: Why your balls shrink when you use steroids


Steroids (often called anabolic-androgenic steroids (AAS) or anabolic steroids) are becoming more popular among recreational and non-professional power athletes. It is estimated that there are approximately three million steroid users in the USA. As more people look for steroids and start using them, the abuse of steroids and their side effects are becoming major concerns. In this article, we are going to tackle one of the most well known side effects of steroid use: testicular atrophy, better known as shrinking balls

Does steroid use really cause testicles to shrink (testicular atrophy)? If it does, why?

YES. Steroid causes testicles to shrink. But why?

Steroids are synthetic ‘derivatives’ of testosterone. In other words, they mimic natural testosterone, but NOT PERFECTLY. When the testosterone level is artificially increased by uptake of steroids, the bio-chemical signals that control the  body’s hormone cycle gets out of balance. While on steroids, the concentration of androgens in the whole body is high, but the testosterone concentration in the testicles is usually significantly lower due to negative feedback from the brain.

To better understand how this bio-feedback cycle worked, researchers undertook experiments to look at what happened to rat testicles when they were placed on high doses of anabolic steroids. They discovered a reduction in leydig cells (which produce testosterone) and germs cells (precursors to sperm cells) and structural changes in the tubules where sperm develop. When testosterone levels in the blood are artificially raised by use of anabolic steroids, the brain sends a signal to the balls to stop producing testosterone. Just like with other tissues, if you don’t use it, you lose it. As tissue in the testicle becomes less active, it begins to atrophy (and no, lots of sex doesn’t help).

Do shrunken testicles lead to difficulties conceiving?

USUALLY. Steroid users often have difficulty conceiving (especially if they experience significant testicular atrophy).

Testicles mainly comprise two types of cells—germ cells which make sperm and Leydig cell which secrete testosterone. Because both cell types diminish with androgen use, a common side effect of steroids is low (or zero) sperm counts and low natural testosterone levels.

These side effects have caused researchers to investigate the possibility of developing an androgen based hormonal contraceptive for men. In the quest to develop a male birth control pill, many studies have been done on using various forms of testosterone in reducing sperm production to values less than 1 million per mL . Due to various side effects and other issues, a hormone based male contraceptive has never been released, but the studies have shown that androgen based drugs (including anabolic steroids and testosterone replacement therapy) are effective at shutting down sperm production.

Can testicles go back to normal?

YES and NO.

In general, once steroid use stops, the testicle begins regenerating lost tissue. Studies in rats show that the process is slow and often doesn’t recover the full pre-steroid use size (although it can get very close). Leydig cell counts often remain lower than original, suggesting that testosterone levels may be reduced in the long run. In practice, the longer period you used the steroid for (or the higher dose you used), the longer time you will need for your testicles to recover. Most men are able to recover most of the lost size but may notice that they don’t get quite back to the original size, a lower baseline testosterone level or permanently reduced sperm count. This is especially true for long term or high dose users.

Is there any way to prevent testicular shrinkage for steroid users?

The best way to prevent damage is to not use to begin with. Steroids have a number of other health risks including higher risk of cardiovascular incidents, liver issues and permanent infertility. However, there are a few tricks that can help prevent testicular atrophy.

Using Human chorionic gonadotropin (hCG) during or in-between cycles is a common practice among steroid users. The hCG, which mimics LH, is often used to avoid the negative feedback on LH and to restart testosterone production by testis. Use of hCG concurrently with TRT or steroid cycle may reduce impact of external androgens on testicular function.

Endocrinologists and many urologists are trained on male hormones and reproduction and can help men identify alternative drugs or therapies to improve recovery of lost tissue, prevent atrophy and maintain fertility. Many of these doctors are very approachable and can be great partners to develop a plan that can help optimize your health to meet goals in the gym and in life.


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Sara SDx

Sara SDx

Editor of Don't Cook your Balls, Co-Founder of, Health Coach and Men's Health Advocate. Passionate about sperm, men's health and helping people build their families.
Sara SDx

Author: Sara SDx

Editor of Don't Cook your Balls, Co-Founder of, Health Coach and Men's Health Advocate. Passionate about sperm, men's health and helping people build their families.