About Sperm

Overview

Spermatozoa cells, or sperm, are the reproductive cells produced by men that, under the right conditions, join with a female egg to form a zygote, or fertilized cell, which ultimately divides and multiplies to create a new life in the form of an embryo. The quality and quantity of sperm cells produced by a man help determine his fertility.

Description

Sperm cells are the smallest cell in the human body. They are described as having three main parts: a head; a mid-piece, or neck; and a tail, or flagellum. The head contains the nucleus of the cell and the chromosomes that supply DNA necessary for the transfer of hereditary information. The mid-piece contains the mitochondrion, which produces energy for the cell. The tail propels the sperm forward.

Location

Sperm cells are produced in the testes and stored in an area of the scrotum above the testes called the epididymis. They travel in the seminal fluid that is discharged from the penis during ejaculation.

Significance

Sperm cells carry chromosomes that determine the gender of a new offspring. Sperm cells that carry an X chromosome create a female, and sperm cells that carry a Y chromosome result in a male. Unlike every other human cell that contains a full 46 chromosomes, sperm cells contain 23 chromosomes. When joined with a female egg that also contains 23 chromosomes, they create a zygote, which is a complete cell containing 46 chromosomes.

Quantity

The average sperm count in one ejaculation is 180 million sperm, or 66 million/ml semen. Men with fewer than 20 million/ml sperm are likely to have fertility problems, according to Dr. Charles Lindemann, professor of biological sciences at Oakland University. Only about 200 of these sperm reach the female fallopian tube and only one sperm cell is required to fertilize an egg.

Quality

Sperm can have deformities such as undersized or oversized heads or curly or double tails. To be considered healthy and fertile, at least a third of a man's total sperm should have normal cell shape and structure.

Lifespan

Sperm that enter a woman's vagina can live in her cervix for up to five days and during that time are capable of fertilizing an egg. Sperm deposited outside of the body will live only up to a few hours.

Considerations

To produce healthy, high-quality sperm, the Mayo Clinic recommends maintaining a healthy weight and eating a balanced diet that includes plenty of antioxidant vitamins from fresh fruits and vegetables and specific minerals such as zinc and selenium. Keep stress under control and get plenty of physical activity, but don't over-exercise to the point of exhaustion or you may produce fewer or lower-quality sperm.

Having sex, including masturbation that leads to ejaculation, helps maintain sperm quality and quantity and increases fertility by increasing the number of normally shaped, highly mobile sperm produced.