15th April 2024

Male infertility: Oligospermia & Azoospermia

Infertility, by definition, is the inability to conceive after frequent unprotected sexual intercourse for 1 or 2 years.

Aetiology

There are various causes of male infertility

• Primary spermatogenic failure
• Congenital – Anorchia, testicular dysgenesis, Cryptorchidism
  • Acquired – trauma, infection, varicocele, surgery, testicular tumour
• Genetic disorders
  • Klinefelter’s
  • Kallman syndrome
• Obstructive azoospermia
  • Congenital: Prostatic cysts, absence of vas deferens
  • Infection, surgery
• Hypogonadism
• Pharmacological
  • Anabolic steroids, cytotoxic

Investigations

Semen analysis

If the results of a patient’s semen analysis are consistent with the WHO criteria, then only one test is sufficient, however, if the patient has abnormal results in at least two tests, then further investigations are required, the repeat test should be repeated after a period of 3 months to facilitate the completion of a cycle of spermatozoa. The semen sample should be collected after a minimum of 2 days but not more than 7 days of sexual abstinence and delivered to the laboratory within 1 hour.

Oligozoospermia – <15 million spermatozoa/ml

Azoospermia – < 1 million spermatozoa / ml

Asthenozoospermia – <32% progressive motile spermatozoa

Teratozoospermia – < 4% normal forms

Screen for chlamydia

Ideally, both partners should be screened for chlamydia.

Laboratory investigations

In a patient with symptoms of hypogonadism, serum hormone levels should be investigated to differentiate between primary and central hypogonadism. Raised LH and FSH are associated with hypergonadotropic hypogonadism. Typically, FSH levels are related to the levels of spermatogenesis, in patients with significantly reduced spermatogenesis FSH levels tend to be increased, however, if the disorder occurs at the spermatocyte/spermatid level FSH levels may be normal.

Ultrasonography

Ultrasonography may be useful in identifying signs of an obstructive cause for infertility, such as dilatation of the rete testis, enlarged epididymis or absence of the vas deferens; it may further help to identify signs of testicular dysgenesis.

References

• National Institute for Health and Care Excellence: Guidelines.  Fertility problems: assessment and treatment. London: National Institute for Health and Care Excellence (NICE) Copyright © NICE 2020.; 2017.
• Weidner W, Colpi GM, Hargreave TB, Papp GK, Pomerol JM, Ghosh C. EAU guidelines on male infertility. Eur Urol. 2002;42(4):313-22.
• Bjorndahl L, Kirkman Brown J, other Editorial Board Members of the WHOLMftE, Processing of Human S. The sixth edition of the WHO Laboratory Manual for the Examination and Processing of Human Semen: ensuring quality and standardization in basic examination of human ejaculates. Fertil Steril. 2022;117(2):246-51.
• Hargreave TB, Mills JA. Investigating and managing infertility in general practice. Bmj. 1998;316(7142):1438-41.