Monday, February 25, 2008

Viagra Can Harm MALE Fertility ...

Researchers have revealed that Viagra, an anti-impotence drug, may have negative effects on male fertility. Experiments have suggested that the use of the drug can harm sperm and may prevent some men from fathering families.
According to researchers from Queen's University in Belfast, northern Ireland, young men who use the drug recreationally could impair their ability to have families and fertility clinics that prescribe Viagra to help men produce sperm for IVF treatments could be preventing some couples from conceiving.
The study, which is to be published in the journal Fertility and Sterility, is based on two sets of experiments. The first involved taking sperm samples from volunteers and then bathing them in weak solutions of Viagra. The aim was to produce a Viagra level equivalent to that found in the blood of a man who had taken a single 100-milligram tablet.
The researchers then compared the behaviour of the treated sperm with standard samples and found the drug had two principal effects. It made sperm more active but also it damaged its acrosome, a cap-like structure that contains enzymes that break down the membrane surrounding a women's egg and allows sperm to fertilise it.
"I think it is worrying that some IVF clinics are using Viagra in order to boost fertility results," Dr David Glenn, a consultant gynaecologist at Queen's University said.