What Is Sperm Concentration?

Typically, male ejaculate, known as semen, contain several million sperm. The exact number of spermatozoa, or sperm, in the ejaculate is referred to as a sperm concentration, or sperm count. Most experts agree that a semen sample that contains at least 40 million sperm is considered to have a normal sperm concentration. Low sperm concentration is a common cause of infertility in many men, and it can be caused by any number of things.

Semen is the thick whitish substance that is ejaculated out of the urethra in the penis during a man's sexual climax. The microscopic sperm needed for conception make up only a small percentage of this substance. The rest of the semen is made up of substances from the seminal vesicles as well as the prostate and urethral glands.

Spermatozoa are produced in the male testicles. Colloquially referred to as sperm, these microscopic tadpole-like swimmers originate from a cell referred to as a spermatagonium. This cell divides into smaller cells, and each section forms into a single spermatozoa, or sperm. Millions of sperm are usually present in male ejaculate, although some of them may be dead or deformed.

Each time a man ejaculates, he releases roughly 2 to 10 milliliters (0.4 to 2 teaspoons). A normal sperm count is 20 million sperm in each milliliter (0.2 teaspoons). On average, three-quarters of these sperm are alive, and one-half of them should be swimming. Two-thirds of the sperm will usually be deformed somewhat.

A sperm sample must first be collected to determine a man's sperm count. The sample is then examined by scientists. If there are fewer than 20 million sperm per milliliter (0.2 teaspoons) or fewer than 40 million sperm in a man's sperm sample, he is considered to have a low sperm concentration. Several samples, each taken a couple weeks apart, are usually needed to determine an accurate sperm concentration.

Oligozoospermia is the medical term for a low sperm concentration. This is one of the biggest causes of male infertility. A number of factors may contribute to a low sperm concentration, including injury or disease of the male reproductive organs. Some experts also believe this condition is hereditary. Environmental factors and lifestyle, such as pollutants or substance abuse, may also contribute to a low sperm count.

Some studies suggest that the average sperm count in males around the world is slowly declining. There may be several reasons for this. For instance, sexually transmitted diseases and environmental pollutants are more common in the 21st century than in previous times. Both of these things have been proven to lower a man's sperm concentration.