Evaluation of Testicular Atrophy with Normal Hormone Levels
Your testicles are likely shrinking due to primary testicular dysfunction affecting the seminiferous tubules (sperm-producing tissue), which can occur even with seemingly "normal" hormone levels—your FSH of 10 and LH of 7 actually indicate mild testicular dysfunction that warrants immediate investigation including semen analysis, genetic testing, and scrotal ultrasound.
Understanding Your Hormone Profile
Your hormone levels are not truly normal despite falling within standard laboratory reference ranges:
FSH of 10 IU/L is elevated. The American Urological Association defines FSH >7.6 IU/L as indicating testicular dysfunction, and men with FSH >7.5 IU/L have a 5-13 fold higher risk of abnormal sperm concentration 1, 2.
LH of 7 IU/L is in the upper-normal range, suggesting your pituitary is compensating for some degree of testicular resistance 1.
Normal testosterone can coexist with testicular atrophy because testosterone production (Leydig cells) and sperm production (seminiferous tubules) are separate testicular functions that can be affected independently 1, 2.
Why Testicles Shrink Despite "Normal" Hormones
Testicular volume directly reflects seminiferous tubule health, not Leydig cell function. The seminiferous tubules comprise 80-90% of testicular volume, so damage to sperm-producing tissue causes shrinkage even when testosterone-producing Leydig cells remain functional 2.
Your hormone pattern (mildly elevated FSH and LH with adequate testosterone) indicates:
- Primary damage to seminiferous tubules 1, 2
- Compensatory pituitary response (elevated FSH/LH) attempting to maintain function 1
- Preserved Leydig cell function maintaining testosterone 1
Essential Diagnostic Workup
Immediate Testing Required
Semen Analysis (Priority #1):
- Obtain at least two analyses separated by 2-3 months, as single analyses are misleading due to natural variability 1, 2
- Your hormone profile suggests oligospermia (reduced sperm count) rather than complete azoospermia 1
- Testicular volume <12 mL is associated with impaired spermatogenesis 2
Genetic Testing (if sperm count <5 million/mL):
- Karyotype analysis to exclude Klinefelter syndrome (47,XXY) and other chromosomal abnormalities 1, 2
- Y-chromosome microdeletion testing (AZFa, AZFb, AZFc regions) 1, 2
Scrotal Ultrasound:
- Measure precise testicular volume (Prader orchidometer or ultrasound) 2
- Evaluate for varicocele, which can cause testicular atrophy with normal hormones and is potentially correctable 2
- Assess testicular architecture for masses or non-homogeneous tissue 2
Complete Hormonal Panel:
- Total testosterone, SHBG (to calculate free testosterone), and prolactin 1, 2
- Thyroid function (TSH, free T4), as thyroid disorders disrupt the hypothalamic-pituitary-gonadal axis 1
Common Causes to Investigate
Varicocele
- Most common correctable cause of testicular atrophy with normal hormones 2
- Physical examination may reveal palpable varicocele 2
- Correction can improve both testicular size and fertility 2
History of Cryptorchidism
- Can result in small testicles with normal hormones even after successful orchidopexy 2
- Associated with reduced testicular size and function 2
Genetic Abnormalities
- Klinefelter syndrome and Y-chromosome microdeletions can present with progressive testicular atrophy 1, 2
- Testing mandatory if sperm concentration abnormal 1, 2
Metabolic and Thyroid Factors
- Thyroid dysfunction, obesity, and metabolic stress can affect the hypothalamic-pituitary-gonadal axis 1
- These are potentially reversible causes 1
Environmental and Medication Exposures
- Exogenous testosterone or anabolic steroids cause testicular atrophy through suppression of FSH/LH 1
- Toxins (lead, cadmium) and occupational exposures can impair spermatogenesis 1
Critical Pitfalls to Avoid
Never start testosterone therapy if fertility is a concern. Exogenous testosterone will completely suppress FSH and LH through negative feedback, causing further testicular atrophy and potentially azoospermia that can take months to years to recover 1.
Do not rely on single hormone measurements. FSH and LH can fluctuate due to pulsatile secretion, and repeat testing may be needed 1.
Do not assume fertility is intact based on testosterone alone. Up to 50% of men with non-obstructive azoospermia and elevated FSH still have retrievable sperm, but testicular atrophy with your hormone profile suggests impaired spermatogenesis 1, 2.
Fertility Preservation Considerations
Consider sperm cryopreservation now if semen analysis shows oligospermia, as progressive testicular atrophy may lead to further decline 1. Once azoospermia develops, even microsurgical testicular sperm extraction (micro-TESE) only achieves 40-50% sperm retrieval rates 1.
Next Steps Algorithm
- Obtain semen analysis immediately (two samples, 2-3 months apart) 1, 2
- Complete hormonal panel including testosterone, SHBG, prolactin, TSH 1, 2
- Physical examination by urologist for varicocele and precise testicular measurement 2
- Scrotal ultrasound for testicular volume and architecture 2
- If sperm count <5 million/mL: genetic testing (karyotype, Y-chromosome microdeletions) 1, 2
- Address reversible factors: thyroid optimization, weight management, eliminate toxin exposures 1
- If fertility desired: discuss sperm banking and assisted reproductive technology options early 1