Infertility - Sperm count and formation
Sperm Count and Formation
The single largest contributing factor to male infertility is sperm count or formation. Testing of sperm involves three studies: count, motility, and morphology.
The number of sperm present in a single ejaculation should be at least 20 million in one milliliter. For a full determination of sperm count before a male is diagnosed as infertile, testing should be performed more than once. Oligospermia is the reduced count of sperm; azoospermia is the complete absence of sperm.
Several factors influence sperm production. Alcohol consumption, drug use, and restrictive clothing all reduce sperm count. Blocked ducts in the epididymis or in the vas deferens can also reduce the number of sperm present during ejaculation. Low hormone levels may reduce sperm count. Methods for reversing or correcting low sperm count problem can range from the simple—elimination of affecting factors such as alcohol—to the difficult—surgical reparation of the vas deferens to remove blockage.
Motility is the ability of the sperm to travel through the fluid present. A normal score for sperm motility is that two hours after ejaculation, 50 percent of the sperm are still actively swimming. If the sperm die unusually quickly, it is less likely that one will make the passage through the female cervix and uterus and meet up with the egg in the fallopian tube.
The structure of the sperm (morphology) is a small oval body with a whip-like tail that is used to propel the sperm through the uterus. The tip of the sperm body has a cap with enzymes that deteriorate the protective coating on the ovum when the two press together. Sperm that is misshapen, or missing a tail or the enzyme cap, will not be able to successfully penetrate an ovum. In a morphology test, at least 60 percent of the sperm should be normally structured.
Motility and morphology problems present barriers to natural fertilization. Some men are able to successfully impregnate their spouses without surgical intervention, despite deficient sperm; others may require extensive intervention.