Dr LeGrice came under criticism for tactless comments, which he later denied, when he was first confronted about the problems besetting the organisation.
In a Herald interview on January 11, he dismissed the delays as "just a small hiccup" and nothing more than a nuisance.
Dr LeGrice, who joined the board 18 years ago, said yesterday that his retirement had nothing to do with the way he had handled the situation.
He denied the board had put him under any pressure to leave following the debacle that saw Southern Cross, the country's largest health insurer, struggling to deal with floods of disgruntled clients.
"That is nonsense ... and I am a man of integrity."
Dr LeGrice said he had been unanimously re-elected chairman of the board last November and members were disappointed he was going.
He said the board had known he was originally planning to step down at the annual general meeting this October.
But he then decided after the resignation of Mr Bowie that it would be a good idea to bring his retirement forward to help in the search for a new chief executive.
Dr LeGrice and the board had agreed about three weeks ago that director Bryan Kensington should take over as chairman.
Mr Kensington, a board member since 1991, chairs the Southern Cross audit committee and oversaw the insurer's efforts to reduce the claims backlog.
Claim processing times returned to normal just over a month ago, and some clients received extra compensation for their inconvenience.
Mr Kensington once chaired the Institute of Directors' Auckland branch, as well as Ernst & Young, Radio New Zealand and the New Zealand advisory board of WestpacTrust.
Mr Kensington said Dr LeGrice had done a huge amount of work for Southern Cross.
nzherald.co.nz/southerncross
