Air-drying technique could let men store sperm at home

MEN waiting for in-vitro fertilisation treatment may one day be able to store their sperm at home, it was revealed yesterday.

Scientists have developed a way of air-drying sperm that allows it to be kept at room temperature without any special conditions.

It means sperm could be stored next to the eggs in a normal refrigerator or even in a man's sock drawer, if he wished.

When needed, the dried sperm pellet could be re-suspended in a drop of biological fluid similar to that in which human eggs are held.

An IVF technique called intracytoplasmic sperm injection (ICSI) would make fertilisation possible by injecting formerly dried sperm directly into an egg.

Researchers from Saudi Arabia told scientists meeting in Spain how they had successfully produced embryos from air-dried sperm.

The technique involves first smearing a sample pellet of washed sperm on to a glass slide.

This is then left to dry for two or three hours in a special cabinet that uses flowing filtered air to ensure no contamination by dust or bacteria. The dried sperm can then be stored.

Unlike conventional techniques, no special freezing equipment is needed that has to be carefully programmed to ensure sperm is not destroyed by cooling too fast or too slowly.

Sperm is traditionally stored in large liquid nitrogen tanks together with a protective chemical that must be removed before fertilisation.

Dr Daniel Imoedemhe, from the Centre for Assisted Reproduction in Jeddah, Saudi Arabia, who led the research, said:

"These methods are time-consuming and cumbersome compared to our simple technique of air-drying that just requires re-suspension before use.

"The process can be further simplified by allowing patients to take responsibility for storing their air-dried sperm at home."