Conditions imposed by the body of women on semen for fertilization

Conditions imposed by the body of women on semen for fertilization

NEW YORK (Reuters Health) - The female reproductive system is designed in a "unique" way to get rid of weak sperm, scientists at Cornell University in New York say.

A series of "pressure points," such as uterine constriction and fallopian tubes, are the biological equivalent of an aggressive cycle, scientists say. As a result, only the strongest sperm cells can rush through the "bottleneck" to reach the egg, creating the process of controlling the quality of the fertilization, according to Daily Mail.

 This result can help improve fertility testing, as well as the couple's chances of pregnancy.

"If you look at the anatomy of the mammalian reproductive system, you can see that the dimensions of the channel that leads to the egg are not constant," said Dr. Aliziza Abasborad, a chemist and lead author of the study. "The overall effect of these restrictions is to prevent slow sperm from passing through them , And the selection of sperm with higher mobility. "

Apasborad and his team used sperm from human and bull to make a comparison. She then analyzed her movement in a "microfluidic" device, which mimicked the bottlenecks recorded in the woman's body.

The researchers found that the sperm collect at the point of suffocation, with the passage of species faster through the channel of the female reproductive system. They also observed that at this stage, active sperm only compete with other similar quality, neither slower nor weaker.

One experiment saw a sperm movement of 3.3 inches (84.2 mm) per second across these restrictions, while millions of other sperm fell back, adding more weight to a suggestion that the female body was involved in the selection process.