Causes of Male Infertility

Infertility is the inability to conceive after one year of unprotected intercourse.
25% of couples will experience an episode of infertility. It is of 2 types:
•    Primary infertility
•    Secondary infertility

PRIMARY INFERTILITY refers to couples or patients who had no previous successful pregnancies.
SECONDARY INFERTILITY refers to couples who have previously conceived regardless of outcome, but are currently unable to conceive
•    Infertility problems arise as a result of hormonal dysfunction of hypothalamic-pituitary-gonadal axis. Approximately :
•    50% of infertility problems are due to an abnormality in the female partner,
•     40% to an abnormality in male partner and
•     remaining 10% to abnormalities in both partners.

Male Infertility

Of men with infertility problems:

• 50% have idiopathic adult seminiferous tubular failure
• Approximately 20% have a varicocele with oligospermia
• About 10% have ejaculatory abnormalities
• 10% have obstructive causes and
• 10% have endocrine abnormalities

Causes of Male Infertility

Testicular Causes

Adult Seminiferous tubular failure

1) Primary:
•    Idiopathic decrease in sperm count or sperm motility
•    Normal sexual function
•    No history of cryptorchidisim, infection, inflammation or varicocele
2) Secondary:
•    In some cases specific causes can be identified
1.    Cryptorchidism
2.    Medications:
–    estrogens,
–    antiandrogens,
–    intramuscular testosterone,
–    high-dose nitrofurantoin
–    Chemotherapy (especially Cyclophosphamide, Chlorambucil)
–    Cimetidine( antiandrogen & reduces sperm count)
3. Envoirmental agents & workplace toxins:
–    Pesticide dibromochloropropane (DBCP)
–    Ethylene
–    Lead
4.    Physical stress of illness
–    Chronic illnesses
5.  Testicular carcinoma
6.  Immotile cilia syndrome

Varicocele

( due to disturbance of intratesticular  thermoregulation)

Defective Androgen Production

1.    Congenital adrenal hyperplasia

2.    Certain drugs (spironolactone, ketocanazole, alcohol, marijuana and aminoglutethimide)

3.    Uremia

Post Testicular Causes

Abnormalities of ejaculation

(increased volume, decreased volume, retrograde ejaculation , absent ejaculation )

1.    Diabetic or other autonomic neuropathies

2.    Sympatholytic drugs (phenoxybenzamine)

3.    Retroperitoneal lymph node dissection for testicular tumor

4.    Trauma

5.    Transurethral surgery

Obstruction of seminal ducts

(causing oligospermia or Azoospermia)

1.                idiopathic

2.                infection

3.                trauma

4.                congenital

5.                vasectomy

Genitourinary infection

Immunological infertility

Pre Testicular Causes

Endocrinopathy

1) hypothalamic-pituitary dysfunction

2)  androgen insensitivity state

Sexual dysfunction

1-    Erectile impotence

2-    Premature ejaculation

3-    Inadequate coital technique

4-    Ejaculation of excessive frequency