A helpline has been set up by the Lakes District Health Board after details of women who had abortions was mistakenly released to the media.
Lakes DHB chief executive Ron Dunham said it was deeply disappointing that an excel document containing coded patient information had been released to a member of the media.
The data was mistakenly released by a junior staff member who was assisting on an Official Information Request. The staff member did not follow standard process.
The coded data includes the National Health Index number, date of birth and ethnicity of 625 women who have used the district health board's termination of pregnancy service.
"Although the women cannot be identified by the coded information released we are taking the situation seriously. A dedicated helpline has been established, anyone with concerns can call 0800 525 371," Mr Dunham said.
"The DHB is working closely with the Ministry of Health and the Privacy Commissioner.
"I understand the concern this will cause for the affected women and I apologise for this."
A full review will be carried out by Lakes District Health Board supported by the Ministry of Health, the health board said in a statement.