Male Factor Infertility


Many couples experiencing difficulty conceiving may be surprised to hear that male infertility is almost as likely as female infertility to be involved in a couple’s inability to achieve pregnancy. Male infertility can be caused by any of a number of conditions or factors. In order to treat the problem, we must understand its source. Potential causes of male infertility are:



  • Varicocele
  • Azoospermia
  • Problems with the Vas Deferens or Epidydimus
  • Hormonal Problems
  • Genetic Factors
  • Illness
  • Environmental Factors and Lifestyle


The most common identifiable cause of infertility in men is the Varicocele, a condition in which enlarged veins in the scrotum interfere with proper temperature and hormonal regulation of the testicular tissue. These veins normally circulate blood away from the testicles thus performing a cooling function. When there is a partial vein blockage, blood circulation decreases and the temperature of the testicular tissue increases. A varicocele can usually be treated surgically by a urologist; however, fairly often surgery does not improve a man’s sperm quality to a level where natural conception may occur.

Varicoceles are found in approximately 15% of the general population, including adolescents and adults, in 35% of men with primary infertility, and in 80% of men with secondary infertility. Improvements in seminal variables, testicular size, and testicular histology have been observed after surgery. Varicocele repair has been reported to improve spermatogenesis in 50%-80% of patients, and as many as 30%-40% will initiate a pregnancy after the procedure.


Azoospermia, or complete lack of sperm in the ejaculate is present in about 1% of the general population. Obstructive Azoospermia is the second major cause of infertility in men. In this condition, sperm are being produced by the testicles but a blockage or obstruction of the reproductive tract impedes them from getting into the ejaculate.

Problems with the Vas Deferens or Epidydimus

The epidydimus and vas deferens are part of a duct system that delivers the sperm cells from the testicles into the ejaculate. Any blockage along this duct system may cause azoospermia.

Azoospermia can also be induced, as it is the case of men who undergo a vasectomy, which results on a permanent blockage of the ducts (vas deferens) bringing the sperm into the urethra. This is usually done for family planning purposes.

In some men, a condition called congenital absence of the vas deferens (CAVD) can occur which will also result in azoospermia. Blockages can sometimes be corrected surgically. However, when this is not possible sperm cells can be aspirated from the epidydimus or from the testicular tissue for use with IVF-ICSI.

Hormonal Problems

Reproductive endocrine imbalances (hormone problems) can affect a man’s sperm production, overall well being, and libido (sex drive). Men with hormonal problems may develop non-obstructive azoospermia and tend to have underdeveloped testicles. In many of these cases fertility specialists will evaluate blood hormone concentrations (FSH, LH, Testosterone). The treatments usually require hormone medication in combination with In Vitro Fertilization.

Genetic Factors

Men with certain rare genetic conditions such as Klinefelter’s syndrome (47,XXY), abnormalities (deletions) of the Y chromosome, and cystic fibrosis mutations (particularly the 5T allele) will also have azoospermia. In additions, balanced chromosomal rearrangements (particularly translocations or inversions), and the XYY syndrome are associated with oligospermia (low sperm count).


Several other conditions which can affect the male reproductive tract will either cause temporary, or in many cases permanent infertility. Acute infections such as smallpox, mumps, sexually transmitted diseases such as Chlamydia and Gonorrhea, Epididymitis and other viral infections. Chronic infections such as Tuberculosis, Leprosy and Prostatitis may result in severe male infertility.

Other conditions also known for causing male infertility are Undescended Testes (Cryptorchidism), Previous Surgery for Inguinal, Scrotal or Retroperitoneal Hernias, Bladder neck surgery, Major Systemic Illnesses (Especially Hepatic or Renal), Sexual Dysfunction and/or Ejaculatory Disturbances such as Retrograde Ejaculation and/or various Neurological Disorders associated with Spinal Cord Injury (SCI), or Erectile Disfunction (ED).

Environmental Factors and Lifestyle

Infertility in the male can also be caused by direct or indirect injury to the testes. Examples of direct injury are testicular or pelvic trauma, heat or irradiation, whereas indirect injury is mostly related to life style and can be induced by a variety of factors among which cigarette smoking, the use of recreational drugs such as Marijuana/Cocaine, the use of anabolic steroids, alcohol, certain vaginal lubricants and certain types of underwear are well known.

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