Infertility is defined as “the failure of a couple to conceive after one year of unprotected intercourse.” Roughly 15% of married couples attempting their first pregnancy experience some degrees of difficulty to conceive. The male factor plays a significant role in about 50% of infertile couples.

Causes of Male Factor Infertility

  • Age: Generally, a man’s fertility starts declining at around the age of 35 as the quality of a man’s sperm diminishes. In addition, sperm motility can also decline with age.
  • Immune disorders: Problems with the immune system can cause a man’s body to treat sperm as if it were a foreign matter. As a result, the immune system may produce antibodies to fight and destroy the sperm.
  • Cancer treatments: Depending on the location of the treatment and the drug and dosage used, chemotherapy and radiation may contribute to male infertility.
  • Sexually transmitted diseases (STDs):  STDs may damage the parts of the body that transport sperm through the reproductive tract.
  • Testosterone, Androgel, and other male hormone substitutes:  Used in lieu of antidepressants or as performance-enhancing additives, they increase testosterone levels, but may also be responsible for halting sperm production.
  • Other factors: Lifestyle and environmental factors may lead to issues with a man’s sperm.


  • Hypothalamic disease
  • Isolated gonadotropin deficiency (Kallmann’s syndrome)
  • Isolated LH deficiency (“Fertile eunuch”)
  • Congenital hypogonadrotropic syndromes
  • Pituitary disease
  • Pituitary insufficiency (tumors, infiltrative processes, operation, radiation)
  • Hyperprolactinemia
  • Hemochromatosis (iron overload)
  • Exogenous hormones (estrogen-androgen excess, glucocorticoid excess, hyper and hypothyroidism)


  • Chromosomal abnormalities (Klinefelter’s syndrome, XX disorder, XYY syndrome)
  • Noonan’s syndrome (male Turner’s syndrome, X0)
  • Myotonic dystrophy
  • Sertoli-cell-only syndrome (germinal cell aplasia)
  •  Gonadotoxins (drugs, some trace metals, thermal exposure, radiation)
  •  Orchitis or systemic disease (renal failure, hepatic disease, sickle cell disease)
  •  Cryptorchidism
  • Varicocele
  • Mutation of LH and FSH receptors


  • Disorders of Sperm Transport
    • Congenital disorders such as Young’s syndrome or cystic fibrosis; acquired disorders such as infections, vasectomies or surgeries leading to damaged ducts; functional disorders such as diabetic neuropathy and spinal cord injury
  • Disorders of Sperm Motility or Function
    • Congenital defects of the sperm tail; maturation defects; immunologic disorders or infections
  • Sexual dysfunction 1

A deficiency in any of these factors may cause infertility in men. Although sperm count is important, sperm motility and forward progression appear to be even more crucial in determining the likelihood of the sperm fertilizing the egg. Despite a low sperm count, many men with high-quality sperm may still be fertile.

As a result of these many male infertility factors, it is important to perform semen analysis early on in the attempt to determine the reasons for infertility. Two to three analyses should be performed over a period of two to six months since sperm quality can change over time. These tests will help give doctors a broader overview of any infertility issues related to the man’s sperm.

Contact Brown Fertility today to learn more about male factor infertility and its possible impact on you.

Major parts of this handout were directly taken from the following sources:

  1. Perloe, Mark, M.D.: with special thanks.