Bounty

US scientists have developed an IVF technique with the selection capability of an egg, it has been revealed.

Researchers at Yale School of Medicine said the method allowed them to ensure that only sperm with the highest DNA integrity was used during the procedure.

Study leader Gabor Huszar claimed previous investigations had mistakenly assumed that males with a high sperm count would automatically be fertile.

Such an approach said nothing about the sperm's ability to attach to the female gamete, he explained.

Mr Huszar said: "Our results could help address the fact that approximately 40 percent of infertility cases can be traced to male infertility."

"We have now found a biochemical marker of sperm fertility so that we can select sperm with high genetic integrity."

Copyright Press Association 2010