Decreasing sperm counts worldwide have been recorded, falling by 50 percent from levels measured in the 1930 (Auger, 1995). Sperm count can be increased by avoiding toxic environmental factors. Environmental influences such as overexposure to: Industrial chemicals, heavy metals, radiation, and overheating of testicles cause disrupted endocrinological axes and birth defects, leading to lower sperm counts in humans. Sperm is defined by the American Society For Reproductive Medicine as male sex cells or "spermatozoa" that are produced in the testes (ASRM,1996-2015). In humans, the production of sperm requires functioning testicles, hypothalamus, and pituitary glands. Once the sperm are produced in the testes they are transported through tubes and mix with semen to be ejaculated out of the penis. Conception problems arise with abnormal sperm morphology, motility and function.
Sperm count is the number of sperm in semen ejaculated during an orgasm. To test the sperm count first a man ejaculates into a collection cup, then tested in a machine that looks for a certain type of protein. A normal sperm count is 20 milliliters or higher (Mayo, 1998-2015). There have been numerous studies indicating sperm count reduction worldwide. In 61 studies on worldwide sperm count reduction were published in 1996 and researchers discovered a connection between agriculture chemicals and low sperm count. The18 regions with the lowest average sperm counts include the state of Iowa, and the countries of Thailand and Nigeria. Also, in New York the sperm counts have decreased by 120.6 x 106 sperm per ml of ejaculate in 1938 to a low 79.0 x 106 sperm per ml of ejaculate in 1976. .
Hormones, such as testosterone and estrogen, tell the cells in the human body what to do, differentiate males from females and regulate reproduction. In the review, "A Sea of Estrogens," John Briggs cautions that endocrine disruptors, such as pesticides, pharmaceuticals and plant hormones affect human reproductive systems by mimicking the effects of certain hormones (1995).