The reason for the significant demand for donor eggs from a top IVF clinic remains unknown.

One of Australia’s leading fertility clinics has announced it will no longer allow families to source donor eggs from a major international egg and sperm bank.

IVFAustralia announced it will no longer be facilitating new arrangements using donor eggs from The World Egg and Sperm Bank last week.

When asked why the decision had been made, a spokesperson said: “IVFAustralia regularly reviews its donor programs and provider arrangements.

“As part of this process, our arrangement with The World Egg and Sperm Bank has now concluded, and we are in the process of establishing a new partnership with an alternative provider.”

9news.com.au has attempted to contact The World Egg and Sperm Bank for comment on multiple occasions.

9news.com.au is not suggesting The World Egg and Sperm Bank has engaged in any wrongdoing, just that IVFAustralia has decided not to utilise its services anymore.

The World Egg and Sperm Bank is a privately owned US-based company and expanded to Australia this year.

IVFAustralia first announced the significant “update” to its donor egg program in an email to customers.

“Please be advised that IVFAustralia will no longer be facilitating any new arrangements using donor eggs sourced from The World Egg and Sperm Bank,” it read.

“We know this news may be unexpected and may feel deeply disappointing, especially if you had been spending time considering this pathway.”

IVFAustralia confirmed it is working to establish new donor egg “collaborations” and expect to have them in place in the coming months.

The email also reassured clients already in the process of using donor eggs from The World Egg and Sperm Bank that they would have their current arrangements honoured.

“You will be able to proceed as planned.”

A spokesperson for IVFAustralia told 9news they “recognise this news may be distressing for patients, and our team is here to provide support.

“It’s our priority to establish a new arrangement and we are actively working to establish a new partnership with an alternative provider.”

They said IVFAustralia’s donor team is available to help Australians navigate finding a known donor.

They also encouraged patients ”who are ready to begin their egg donor pathway” to look into IVFAustralia’s local egg donor program.

“We continuously seek to attract new local donors to the program,” they said.

IVF births have grown exponentially across Australia in the last 40 years.

About one in every 16 babies born in the country are born via IVF these days.