What can be done to address ongoing low semen volume?

Evaluation and Management of Low Semen Volume

The first step is to identify the underlying cause through physical examination checking for vas deferens bilaterally, testicular size, and varicoceles, combined with semen pH measurement and hormonal testing (testosterone and FSH), as treatment targets the etiology rather than the symptom itself. 1

Critical Initial Physical Examination Findings

• Palpate bilaterally for vas deferens to rule out congenital bilateral absence of vas deferens (CBAVD), which can be diagnosed by physical examination alone and requires no medical treatment—only sperm retrieval with ICSI for fertility. 1, 2

• Assess testicular size and consistency carefully, as normal-sized testes suggest obstruction (potentially treatable) while atrophic testes indicate spermatogenic failure (non-obstructive cause). 1, 3

• Examine for palpable varicoceles, as only clinical (palpable) varicoceles warrant treatment and improve semen parameters, while non-palpable varicoceles should never be treated. 1, 2

• Perform digital rectal examination to assess prostate size and consistency. 1, 2

Essential Laboratory Tests

• Check semen pH immediately, as acidic semen (pH <7.0) with low volume (<1.4 mL) strongly suggests ejaculatory duct obstruction or CBAVD. 1, 2

• Measure serum testosterone and FSH, as low testosterone with low/normal FSH indicates hypogonadotropic hypogonadism (treatable with gonadotropins), while elevated FSH (>7.6 IU/L) suggests primary testicular failure. 1, 2, 4

• Perform post-ejaculatory urinalysis when volume <1 mL (except in bilateral vasal agenesis or hypogonadism) to diagnose partial or complete retrograde ejaculation. 1, 2, 5

When to Order Imaging

• Reserve TRUS or pelvic MRI for suspected ejaculatory duct obstruction only—specifically when semen is acidic, volume <1.4 mL, with azoospermia or severe oligospermia with very low motility, normal testosterone, and palpable vas deferens. 1, 2

• Do not routinely order scrotal ultrasound to hunt for varicoceles, as only palpable varicoceles benefit from treatment and ultrasound-detected subclinical varicoceles should not be treated. 1, 2

Treatment Based on Specific Etiology

Ejaculatory Duct Obstruction

• Transurethral resection of ejaculatory ducts (TURED) is the definitive treatment when TRUS or MRI confirms dilated seminal vesicles and ejaculatory ducts. 1, 2

Hypogonadotropic Hypogonadism

• Treatment with human chorionic gonadotropin (hCG) normalizes testosterone levels, sperm concentration, and semen volume, as demonstrated in case reports showing successful conception. 4
• Never initiate testosterone replacement therapy in men desiring fertility, as it suppresses spermatogenesis. 2

Palpable Varicocele

• Varicocelectomy is indicated for palpable varicoceles with abnormal semen parameters, as it improves semen parameters and may restore sperm in ejaculate for men with azoospermia. 1, 2

Congenital Bilateral Absence of Vas Deferens

• No medical or surgical treatment restores ejaculatory volume—proceed directly to sperm retrieval (TESE/MESA) with ICSI for fertility. 1, 2
• CFTR gene testing for the female partner is mandatory before proceeding with assisted reproduction. 1, 2

Lifestyle and Medication Factors to Address

• Discontinue anabolic steroids immediately, as they are associated with reduced fertility. 6, 2

• Review finasteride dosing, as 5 mg/day is associated with reduced semen volume (though 1 mg/day data are inconclusive). 6

• Counsel on alcohol consumption, which results in slightly lower semen volume and poorer sperm morphology. 6, 2

• Address smoking cessation, as smokers have slightly reduced fertility. 6, 2

• Optimize diet, as poor diet results in reduced fertility. 6, 2

Genetic Testing Before Assisted Reproduction

• Karyotype testing is mandatory for azoospermia or severe oligospermia (<5 million/mL). 1, 2

• Y-chromosome microdeletion analysis is required for azoospermia or sperm concentration <1 million/mL. 6, 1, 2

• Genetic counseling should precede ICSI, as genetic abnormalities may be transmitted to offspring. 1, 2

Critical Pitfalls to Avoid

• Do not attribute low semen volume to stress alone, as stress is associated with reduced sperm progressive motility but has no association with semen volume. 6, 2

• Do not delay genetic testing—results impact counseling and treatment decisions before proceeding with assisted reproduction. 1, 2

• Avoid treating subclinical varicoceles detected only on ultrasound, as this does not improve semen parameters or fertility rates. 1, 2