Photo: © 2009 AAP/WESTERN PLAINS ZOO

A new advertising campaign launched today by the country's leading IVF clinics asks men to give generously, telling them "You've got millions to spare, we only need one" and "A donation to us won't save a life, hopefully it will create one".

Donor numbers have dwindled dramatically in recent years following changes to the law that removed a donor's right to anonymity.

On top of that, new laws allowing single women and lesbians to use donated sperm has created extra demand, and tougher restrictions have been put in place on overseas contributions.

IVF Australia's Professor Michael Chapman says people currently face a "devastating" wait of a year or longer for sperm.

"If you're in your late thirties and deciding to have children, at that point, that 12 months can mean the difference between you becoming a mother or not," he told the ABC.