More Australians are turning towards using in-vitro fertilisations to have babies, every year.

Often it's done through regulated IVF clinic, but sometimes parents - desperate for a child - search for a sperm donor on social media.

But as this extraordinary case shows, there can be many more risks associated with - as one lawyer put it - the ‘wild west’ - of online sperm donation.

Today, senior reporter Henrietta Cook on the case of a Melbourne man who fathered 27 children, and the fall-out after the women he donated to found each other.