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Infertility: Problems With the Man's Reproductive System

Overview

The most common cause of male infertility is low sperm count. Absence of sperm in the semen is less common, affecting 1 out of 100 men and affecting 10 to 15 out of 100 infertile men.footnote 1

Causes of sperm count problems include:

  • Hormonal problems in the testicles or pituitary gland. The pituitary gland releases hormones that stimulate the testicles to produce testosterone.
  • Testicular injury or failure, either present at birth (congenital) or associated with radiation or toxic chemical exposure.
  • Cancer treatment with certain kinds of chemotherapy or radiation.
  • Antibodies that attack sperm and that also may be present in semen. Sperm antibodies sometimes develop when a man's sperm has been exposed to his immune system (outside of the testicles). This may happen after a vasectomy, an infection, or an injury to the testicles.footnote 2
  • Drug use (some prescription medicines, and cannabis [marijuana] and tobacco use).
  • Structural problems. These include:
    • A varicocele in the testicles.
    • Blocked ejaculation due to a surgical vasectomy.
    • Absence of a vas deferens (a birth defect that may be associated with the cystic fibrosis genes).
    • Retrograde ejaculation (the ejaculation of semen into the bladder rather than out through the penis).
  • Chromosomal problems (such as Klinefelter syndrome).
  • Genetic problems.

See a picture of the male reproductive system.

References

Citations

  1. American Society for Reproductive Medicine and Society for Male Reproduction and Urology (2008). Evaluation of the azoospermic male. Fertility and Sterility, 90(Suppl 5): S74–S77.
  2. Fritz MA, Speroff L (2011). Male infertility. In Clinical Gynecologic Endocrinology and Infertility, 8th ed., pp. 1249–1292. Philadelphia: Lippincott Williams and Wilkins.

Credits

Current as of: March 1, 2023

Author: Healthwise Staff
Medical Review:
Kathleen Romito MD - Family Medicine
Anne C. Poinier MD - Internal Medicine
Adam Husney MD - Family Medicine
Femi Olatunbosun MB, FRCSC - Obstetrics and Gynecology