Is bilateral testicular volume of 9–10 mL concerning in a patient with normal semen analysis and serum testosterone?

Bilateral Testicular Volume of 9–10 mL with Normal Function: Clinical Assessment

Testicular volumes of 9–10 mL bilaterally fall below the 12 mL threshold that defines testicular atrophy and warrant further evaluation despite normal current sperm count and testosterone, because these volumes carry significant long-term risks for cancer development, progressive fertility decline, and indicate reduced testicular reserve. 1

Why This Volume Is Concerning Despite Normal Current Function

Volumes below 12 mL are definitively considered atrophic and associated with significant pathology, including impaired spermatogenesis and increased risk of intratubular germ cell neoplasia (TIN). 2, 1 The critical issue is that your current normal parameters do not eliminate future risk—they indicate you are currently compensating, but with reduced reserve capacity. 1

Cancer Risk Stratification

The most serious concern depends heavily on your age and history:

• If you are under 30–40 years old with testicular volume <12 mL, you face a ≥34% risk of intratubular germ cell neoplasia if testicular cancer develops in one testis. 2, 1
• If untreated, 70% of TIN-positive testes progress to invasive testicular cancer within 7 years. 2, 1
• A history of cryptorchidism (undescended testicles) combined with volume <12 mL markedly increases malignancy risk and mandates intensified surveillance. 1

Fertility Reserve and Progressive Decline Risk

Even with normal sperm count now, volumes of 9–10 mL indicate reduced testicular reserve, meaning you have less capacity to compensate if additional stressors occur (illness, medications, aging). 1

• Testicular volume strongly correlates with total sperm count and sperm concentration—your current normal parameters may decline over time. 1, 3, 4, 5
• Biofunctional sperm parameters (mitochondrial function, DNA fragmentation, chromatin compactness) worsen with near-linear correlation as testicular volume decreases, even when conventional parameters appear normal. 3
• Mean sperm density enters the oligozoospermic range when testicular volume falls below 10 mL, which is precisely your current range. 4, 6

Mandatory Next Steps

1. Obtain Complete Hormonal Evaluation

Draw morning serum FSH, LH, and total testosterone between 08:00–10:00 hours on at least two separate occasions to establish reliable baseline values. 1

• Elevated FSH (>7.6 IU/L) with your borderline testicular volume indicates reduced testicular reserve and impaired spermatogenic capacity. 1, 7
• The LH pattern distinguishes primary testicular failure (elevated LH) from secondary hypothalamic-pituitary dysfunction (low/normal LH). 1
• If total testosterone is low, measure free testosterone by equilibrium dialysis and sex-hormone-binding globulin (SHBG) to differentiate true hypogonadism from binding protein alterations. 1

2. Detailed History Focusing on High-Risk Features

Obtain focused history on these critical red flags:

• History of cryptorchidism (undescended testes) dramatically raises both atrophy and testicular cancer risk. 1, 7
• Use of anabolic steroids, testosterone, opioids, or glucocorticoids can suppress the hypothalamic-pituitary-gonadal axis. 1, 7
• Prior chemotherapy or pelvic/testicular radiation causes irreversible testicular damage. 1
• Family history of Klinefelter syndrome or hypogonadal disorders. 1
• Systemic diseases including diabetes, chronic liver disease, chronic kidney disease, or HIV infection. 1

3. Consider Scrotal Ultrasound

Request repeat scrotal ultrasound with explicit attention to proper measurement technique using the Lambert formula (Length × Width × Height × 0.71) to confirm volume and exclude structural pathology. 1

• Assess for size discrepancy between testes >2 mL or 20%, which warrants further evaluation to exclude pathology. 1
• Evaluate for testicular masses, varicocele, or testicular microcalcifications, which increase cancer risk 18-fold in this population. 7

4. Genetic Testing If Indicated

• Karyotype analysis is mandatory if FSH is elevated and testicular volume is <12 mL to screen for Klinefelter syndrome (47,XXY), the most common genetic cause of primary testicular failure. 1, 7
• Y-chromosome microdeletion testing is required if sperm concentration drops below 1 million/mL or azoospermia develops. 1, 7

Surveillance and Protective Actions

Fertility Monitoring

• Repeat semen analysis every 6–12 months to detect early decline in sperm parameters, as single analyses can be misleading due to natural variability. 1, 7
• Consider sperm banking now before any decline occurs, especially if you are under 30–40 years or have high-risk features. 1

Cancer Surveillance

• Teach and perform monthly testicular self-examination given the 3.6–7.4 times higher risk of germ cell tumors with testicular atrophy. 7
• If you are under 30 years with volume <12 mL and develop testicular cancer, contralateral testicular biopsy is strongly indicated given the 34% TIN risk. 2, 1

Critical Medication Avoidance

• Never start testosterone replacement therapy without first clarifying fertility intentions, because exogenous testosterone suppresses the hypothalamic-pituitary-gonadal axis and causes complete azoospermia that may take months to years to recover. 1, 7
• Avoid anabolic steroids, chronic opioids, and high-dose glucocorticoids, which will completely suppress spermatogenesis. 1, 7

When to Refer to Urology Urgently

• Palpable testicular mass develops. 1
• Rapid testicular atrophy occurs. 1
• Severe oligospermia (<5 million/mL) develops. 1
• Age <30 years with history of cryptorchidism. 1
• Testicular cancer develops in one testis (contralateral biopsy strongly recommended). 2, 1

Common Pitfalls to Avoid

• Do not assume normal current sperm count and testosterone mean no concern—volumes of 9–10 mL indicate reduced reserve and carry long-term risks. 1, 3
• Do not delay hormonal evaluation—FSH levels are critical for risk stratification and management decisions. 1, 7
• Do not start testosterone therapy without fertility counseling—this will cause azoospermia. 1, 7
• Do not ignore age-specific cancer risk—men under 30–40 years with volume <12 mL face ≥34% TIN risk if cancer develops. 2, 1