There are urgent calls for tighter industry regulation as new details emerge into what went wrong in the Monash IVF bungle.

Two separate embryo mix-ups led to the resignation of Monash’s chief executive, Michael Knaap, earlier this month.

WATCH THE VIDEO ABOVE: New details emerge about major Monash IVF bungle.

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In April, Monash IVF revealed a woman at its Brisbane facility had another patient’s embryo transferred to her, which it blamed on “human error”.

A missing embryo was thought to be a counting error, it has now been revealed.

The first woman had a number of embryos successfully frozen.

Months later, when there was one less than she was initially told, doctors said they must have counted wrong.

However, the missing embryo had been successfully transferred into another woman’s uterus.

There was no formal audit at the time, but it was eventually discovered when the birth parents requested their remaining embryos be transferred to another provider.

Monash IVF apologised, expressed confidence that it was an isolated incident, and hired leading barrister Fiona McLeod to lead an independent review.

However, a second mix-up was discovered earlier this month.

Another woman was incorrectly given the wrong embryo at the Monash IVF’s Clayton clinic — in Melbourne — earlier this month.

That led to Knaap’s resignation.

Knaap, who was also a director, was appointed CEO in 2019 and led the company through a period of “significant growth and transformation”.

The company’s chief financial officer, Malik Jainudeen, has assumed the role of acting CEO.

There are now calls for a national regulator to prevent this ever happening again.

“This is a great human tragedy,” bioethicist Dr Xavier Symons told 7NEWS.

“It’s not even about reducing the risk of this happening.

“This needs to be an impossibility.”

The Victorian Health Regulator is conducting its own probe into how the error occurred at the clinic in the suburb of Clayton.

“There is currently a rapid review being undertaken, that is due to report back in three months,” Victorian Premier Jacinta Allan said.

Monash IVF said it’s supporting the families involved.

-With AAP