This can be overcome by using artificial insemination - injecting specially prepared sperm directly into the uterus - to fertilize the egg.

The male places his intromittent organ within the female genitalia, following the piercing of her inner wall, to inject toxic sperm.

It involves injecting single sperm directly into an egg.

Injecting sperm onto the cervix produced pregnancies in 10 percent.

During mating, they fence with one another using their penises attempting to stab and inject sperm in their opponent, while avoiding being fertilized themselves.

The male mounts her from behind to inject sperm.

A second method, using drugs but injecting sperm onto the cervix, had a 19 percent success rate.

One advance that made the new work possible was the ability to fertilize an egg by injecting sperm directly into it.

A popular technique to help infertile men become fathers, injecting individual sperm into individual eggs, alters the fertilization process, researchers have found.