While she found the process of donation through a public cord blood bank somewhat "convoluted", she'd do it again in an instant.

"I'd read about cord blood donation on a flyer I received in a pack before Zoe was born," she said.

"At first I was interested in private cord blood collection, so that we could have the blood stored for our own child or subsequent children if we needed it.

"However it was really expensive so I decided to donate to a public cord blood bank, which meant the blood could be used by anyone who needed it."

Cord blood is used to treat more than 80 diseases, including leukaemia, and has several advantages over stem cells derived from bone marrow for transplants.

Importantly, unlike bone marrow transplants, an exact match is not needed.

Australia has three private cord blood storage companies, and long-term storage costs about $3000 to $3500 for 25 years.

However it's free if you choose to use three public cord blood banks that store samples collected from 11 centres in NSW, Victoria, Queensland and the Northern Territory.

The closest collection centre for South Coast parents is St George Private Hospital, which is where Ms Mills delivered Zoe nine months ago.

"It just took a phone call to organise and then when I was giving birth, a lady came to collect the cord blood," she said.

"I thought that was it, but then she came to visit me in hospital to ask me a number of questions, such as family medical history.

"I also had to have two blood tests after the birth and another question-and-answer session - I didn't realise there was so much follow-up."

Despite that, Ms Mills and her partner Ross Gliddon would not hesitate to repeat the process if Ms Mills falls pregnant again.

"I think some people might start the process and give up after the birth as they're too busy to go and get blood tests," Ms Mills said.

"But I do think it's important to keep going - and I'd do it again as I would hope that if something happened to my child there would be cord blood available to help her."