By Niels E. Skakkebaek & Reproductive Research posted on renchemista.wordpress.com
Between 1990 and 2000 the U.S. teen pregnancy rate plummeted by 28 percent… What if there’s a third explanation, one that has nothing to do with just-say-no campaigns or safe-sex educational posters? What if teenagers are less fertile than they used to be?” “Our Stolen Future” by Theo Colborn predicted this trend… Read it or check out Niels Skakkebaek’s sperm count studies.
Even a high school biology student could see the deformities in the tiny tadpolelike human sperm as they swam about under the microscope. In a single sample, some sperm might have two heads and others two tails, while another might have no head at all. Many didn’t swim right, showing total inactivity or frenetic hyperactivity instead of a strong, steady motion.
Because of the changes in sperm counts and quality and the increase of genital abnormalities had occurred over such a short period of time, the researchers ruled out genetic factors. Instead, the changes appeared due to some sort of environmental factor.”
Over the years, Niels Skakkebaek, a reproductive researcher at the University of Copenhagen, had seen more and more sperm abnormalities, as well as a drop in the typical sperm count. At the same time, the rate of testicular cancer had tripled in Denmark between the 1940s and the 1980s. Skakkebaek also noticed low sperm counts and unusual cells in the testes of men who eventually developed this type of cancer. Were the two findings connected?
Skakkebaek began to research the scientific literature, looking for other studies on sperm count, especially data on men who did not suffer from infertility or other health problems. He and his colleagues eventually reviewed sixty-one studies, most of them from the United States and Europe, but also from India, Nigeria, Hong Kong, Thailand, Brazil, Libya, Peru, and Scandinavia.
The researchers were stunned by what they found. According to data, average human sperm counts had dropped by almost fifty percent between 1938 and 1990. At the same time, the incidence of testicular cancer had jumped sharply, not just in Denmark but in other countries as well. The medical data also suggested that genital abnormalities such as undescended testicles and shortened urinary tracts were on the rise among young boys.
Because of the changes in sperm counts and quality and the increase of genital abnormalities had occurred over such a short period of time, the researchers ruled out genetic factors. Instead, the changes appeared due to some sort of environmental factor.” http://renchemista.wordpress.com/2010/06/05/niels-skakkebaek-reproductive-research/
Niels E. Skakkebaek & Reproductive Research