MedLines: Male Infertility (Part 1)

By Patience Joseph Mamman


Definition: Infertility, in a general sense, can be defined as the inability of a man and a woman to successfully achieve pregnancy despite having regular and unprotected sex for at least a year or more.

The World Health Organization defines Infertility thus: “Infertility is a disease of the reproductive system defined by the failure to achieve clinical pregnancy after about 12 months or more of regular, unprotected sexual intercourse (and there is no other reason such as breast feeding or postpartum amenorrhea)”.

In view of the above then, male infertility will be defined as those conditions that prevent a man from successfully impregnating a female inspite of regular, unprotected sex.

As a way of starting, we wil looking at conditions that affect the sperm. There are basically four types of abnormality associated with the sperm, and they are as follows.


The usual quantity of semen ejaculated at every sexual intercourse averages about 3.5mL and in each mL of semen an average of about 120 million sperm is found with a range of between 35-200 million sperm cells.

So oligospermia therefore refers to a condition where the average number of sperm cells in a one mL of semen falls below 15 million, that is a below normal sperm count. Even though just a single sperm count is needed to fertilize an ovum but nature has designed that a tremendous amount be present because of the harsh and acidic nature of the vagina which may end the lifespan of some of them.

Types of Oligospermia.

  1. Mild Oligospermia: Here, the sperm count is between 10-15million/mL of semen.
  2. Moderate Oligospermia: Here, the sperm count is between 5-10million/mL of semen.
  3. Severe Oligospermia: Here, the sperm count is below 5million/mL of semen.

Implications of Oligospermia

  • Difficulty achieving pregnancy naturally.
  • It could also be an indicator of other medical problems.

Risk Factors/Possible causes.

  • Alcohol consumption.
  • Smoking.
  • Infections like Mumps, gonorrhea.
  • Drug abuse.
  • Exposure to toxic chemicals and radiations.
  • Chemotherapy.
  • Excessive consumption of steroids especially athletes.
  • Genetic disorders.

This is the absence of sperm in an ejaculate.

Types of Azoospermia.

  1. Presticular: This is a type of azoospermia that results from low levels of hormones that trigger sperm production.
  2. Testicular: This is a type of azoopspermia associated with physical and structural abnormalities of the testes e.g Undescended testes, Klinefelter’s syndrome.
  3. Post Testicular. This type of azoopermia arises from mostly obstruction in the post testicular and ejaculatory tract. This is the type found in about 7-51% of men with azoospermia.

If movement is slow, not in a straight line or both, the sperm will have difficulty invading the cervical mucous or penetrating the outer layer covering the ovum. This condition is known as Asthenospermia.
Poor sperm motility may be associated with DNA fragmentation, defficiences, deformity in the structure of the flagellum of the sperm.

This is a condition characterized by the presence of large number of sperms with abnormal morphology. The normal sperm has an oval head, and a long tail but in teratospermia we have sperms with short or mutiple tails, large,round heads or very small heads. The implication of Teratospermia is that such cells will be incapable of fertilizing an egg. The real cause behind this condition is most times not known but certain diseases and habits like Crohn’s disease, coeliac disease and smoking have been known to aid the progression of this condition.