I’m an adult male with 10 mL testicular volume, normal follicle‑stimulating hormone, luteinizing hormone, testosterone and sperm count, a subclinical 3.8 mm varicocele, prior brief scrotal pain and transient yellow semen—what could be causing my concern for testicular atrophy and how should I evaluate it?

Your Testicular Volume Is at the Lower Limit of Normal and Does Not Represent Pathological Atrophy

With 10 mL bilateral testicular volume, normal hormones (FSH 9.6, LH 7.2, testosterone 40 nmol/L), and normal sperm count (40 million/mL), you do not have clinically significant testicular atrophy requiring intervention. Your testicular volume sits just below the 12 mL threshold that defines atrophy, but this threshold applies primarily when accompanied by impaired spermatogenesis, elevated FSH, or infertility—none of which you have. 1

Understanding the 12 mL Threshold

• Testicular volumes less than 12 mL are considered atrophic when associated with impaired spermatogenesis, elevated FSH (>7.6 IU/L), or a history of cryptorchidism—indicating pathological loss of testicular tissue. 1
• Your FSH of 9.6 IU/L falls within the normal range (1–12.4 IU/L) and does not meet the >7.6 IU/L threshold that suggests overt spermatogenic failure. 1, 2
• Your sperm concentration of 40 million/mL far exceeds the WHO lower reference limit of 16 million/mL, confirming normal sperm production despite borderline testicular volume. 1, 2

The key distinction: Testicular volume below 12 mL becomes clinically significant only when fertility parameters are abnormal. Approximately 80% of men with varicoceles remain fertile despite testicular atrophy, so normal sperm count does not exclude varicocele as a contributor to size but does indicate preserved function. 3, 4

Your Subclinical Varicocele Is Not Causing Functional Impairment

• Your 3.8 mm non-palpable varicocele without reflux is classified as subclinical (detectable only on ultrasound, not physical examination). 3
• Treatment of subclinical varicoceles is not effective at increasing chances of spontaneous pregnancy and should only be considered if semen parameters deteriorate or testicular atrophy progresses. 3
• Varicoceles cause ipsilateral testicular volume loss averaging 2.5–3.1 mL in both fertile and infertile men, but this atrophy does not correlate with fertility status or hormonal parameters. 3, 4
• Even subclinical varicoceles can cause testicular damage through higher scrotal temperature, testicular hypoxia, reflux of toxic metabolites, and increased DNA damage—but your normal sperm count and hormones indicate these mechanisms are not currently impairing function. 3

Transient Symptoms Do Not Indicate Progressive Disease

• Your prior scrotal pain that subsided and transient yellow semen that cleared are not indicators of ongoing testicular pathology. 1
• Yellow semen can result from prolonged abstinence, urinary contamination, or transient inflammation—none of which cause permanent testicular atrophy. 1
• Brief scrotal pain without persistent findings on examination does not warrant further investigation in the context of normal fertility parameters. 1

What You Should Monitor Going Forward

Repeat Semen Analysis and Hormonal Profile in 3–6 Months

• Single analyses can be misleading due to natural variability; repeat testing establishes whether parameters are stable or declining. 1, 3
• Specifically monitor FSH—a rise above 7.6 IU/L would suggest underlying spermatogenic dysfunction requiring further workup. 1, 2, 3

Watch for Progressive Testicular Atrophy

• Progressive testicular atrophy (size difference >2 mL or 20% confirmed on two visits 6 months apart) is a strong indication for varicocele repair, even if the varicocele is subclinical. 1, 3
• Request repeat scrotal ultrasound in 6–12 months with explicit attention to proper measurement technique using the Lambert formula (Length × Width × Height × 0.71) to ensure accurate volume calculation. 1

Avoid Gonadotoxic Exposures

• Never use exogenous testosterone or anabolic steroids—these completely suppress spermatogenesis through negative feedback and can cause azoospermia that takes months to years to recover. 1, 2
• Optimize modifiable factors: smoking cessation, maintain healthy body weight (BMI <25), minimize heat exposure to the testes. 2

When to Seek Urology Referral

• Palpable testicular mass develops (requires urgent evaluation for testicular cancer, especially given volumes <12 mL carry ≥34% risk of intratubular germ cell neoplasia in men under 30–40 years if cancer is present). 1
• Rapid testicular atrophy occurs (confirmed size decrease >2 mL or 20% on serial ultrasounds). 1, 3
• Sperm concentration drops below 20 million/mL on repeat analysis (warrants genetic testing including karyotype and Y-chromosome microdeletion analysis). 1, 2
• FSH rises above 7.6 IU/L (indicates worsening spermatogenic dysfunction). 1, 2, 3

Fertility Preservation Considerations

• You do not currently need sperm banking—your sperm count of 40 million/mL and normal hormones indicate excellent fertility potential. 1, 2
• Consider sperm cryopreservation (banking 2–3 ejaculates) only if follow-up semen analysis shows declining sperm concentration approaching 20 million/mL or if you plan gonadotoxic exposures (chemotherapy, radiation). 1, 2

Common Pitfalls to Avoid

• Do not pursue varicocele repair at this time—your subclinical varicocele with normal fertility parameters does not meet criteria for intervention. 3
• Do not assume testicular volume alone predicts fertility—your normal sperm count and hormones override concerns about borderline volume. 1, 4
• Do not start testosterone therapy if you desire future fertility—it will suppress sperm production completely. 1, 2