Testicular Atrophy: Prevention, Diagnosis and When to See a Doctor
Testicular atrophy means a reduction in testicle size, often accompanied by reduced testosterone production or sperm output. In the fitness world it is best known as a side effect of anabolic steroids, but it has many other causes. Here is what leads to it, how doctors diagnose it and when you should get checked.
What testicular atrophy is
The testes have two main functions: producing testosterone in Leydig cells and producing sperm in the seminiferous tubules, which make up most of the testicular volume.
When sperm production falls, the testes shrink. Atrophy can affect one or both testes and may be temporary or permanent.
Normal adult testicular volume is often cited as roughly 15–25 mL, measured with an orchidometer or ultrasound.
Atrophy may be noticed as a change in size or firmness, or discovered during an exam or fertility evaluation.
Common causes
| Cause | Mechanism |
|---|---|
| Anabolic steroids and exogenous testosterone | Suppress LH and FSH, shutting down testicular function |
| Varicocele | Dilated veins raise temperature and impair the testis |
| Orchitis (e.g., mumps) | Inflammation damages tissue |
| Testicular torsion | Loss of blood supply; a surgical emergency |
| Aging, alcohol misuse, liver disease | Hormonal changes and direct toxicity |
| Klinefelter syndrome and other genetic conditions | Primary testicular failure |
Exogenous androgens suppress the hypothalamic-pituitary-gonadal axis through negative feedback. Rahnema et al. (2014) described anabolic steroid-induced hypogonadism, including testicular atrophy and infertility.
A meta-analysis by Christou et al. (2017) found that anabolic steroid users frequently show reduced testicular volume and sperm counts, with partial recovery after stopping.
Varicocele is a common, treatable cause linked to male infertility (Jensen et al., 2017).
Symptoms and recovery
Besides smaller testes, men may notice reduced libido, erectile dysfunction, fatigue, low mood or reduced muscle mass, reflecting low testosterone.
After stopping anabolic steroids, recovery can take months, and in some men hypogonadism persists (Kanayama et al., 2015).
The HAARLEM study (Smit et al., 2021) followed men using androgens and found that testicular volume generally decreased during use and partially recovered after stopping.
Fertility may also be affected even when testosterone recovers. Men planning children should discuss this with a urologist or reproductive endocrinologist.
Diagnosis
Diagnosis starts with a medical history and physical exam, including measuring testicular volume.
- Hormone tests: total testosterone, LH, FSH, estradiol, SHBG, prolactin;
- Semen analysis for sperm count and quality;
- Scrotal ultrasound to evaluate size, structure and blood flow, and to exclude varicocele or tumors;
- Genetic testing if a congenital cause is suspected.
Low LH and FSH with low testosterone suggest secondary hypogonadism, typical of exogenous androgen use; high LH and FSH suggest primary testicular failure.
The Endocrine Society guideline (Bhasin et al., 2018) recommends confirming low testosterone with repeat morning measurements.
Prevention and when to see a doctor
The most effective prevention is avoiding non-medical use of anabolic steroids and other androgens. Medical testosterone therapy also suppresses fertility and should be managed by a physician.
Other measures include treating varicocele when indicated, getting vaccinated against mumps, limiting alcohol and seeking prompt care for testicular pain.
See a doctor urgently for sudden severe testicular pain or swelling, which may be torsion requiring emergency surgery.
Make an appointment if you notice a lump, persistent size change, pain, signs of low testosterone or fertility problems. Do not self-treat with hormonal drugs.
Conclusions from the editorial team
Testicular atrophy has multiple causes, with anabolic steroid use being one of the most common in athletes. Hormonal suppression can lead to reduced testicular size, low testosterone and infertility.
Diagnosis relies on examination, hormone tests, semen analysis and ultrasound. Recovery after stopping androgens is possible but not guaranteed.
Sudden pain is an emergency; persistent changes or fertility concerns warrant a visit to a urologist or endocrinologist.
Related topics on our site: hematocrit for athletes, how to prepare for an SHBG test, and anti-doping rules in Germany.
References
- Rahnema CD, Lipshultz LI, Crosnoe LE, et al. Anabolic steroid-induced hypogonadism: diagnosis and treatment. Fertil Steril. 2014;101(5):1271–1279.
- Christou MA, Christou PA, Markozannes G, et al. Effects of anabolic androgenic steroids on the reproductive system of athletes and recreational users: a systematic review and meta-analysis. Sports Med. 2017;47(9):1869–1883.
- Kanayama G, Hudson JI, DeLuca J, et al. Prolonged hypogonadism in males following withdrawal from anabolic-androgenic steroids: an under-recognized problem. Addiction. 2015;110(5):823–831.
- Smit DL, Buijs MM, de Hon O, et al. Positive and negative side effects of androgen abuse. The HAARLEM study: a one-year prospective cohort study in 100 men. Scand J Med Sci Sports. 2021;31(2):427–438.
- Bhasin S, Brito JP, Cunningham GR, et al. Testosterone therapy in men with hypogonadism: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2018;103(5):1715–1744.
- Jensen CFS, Østergren P, Dupree JM, et al. Varicocele and male infertility. Nat Rev Urol. 2017;14(9):523–533.
- Pope HG Jr, Wood RI, Rogol A, et al. Adverse health consequences of performance-enhancing drugs: an Endocrine Society scientific statement. Endocr Rev. 2014;35(3):341–375.
