A study of women in Wellington who almost died giving birth has found that more than a third of the cases were preventable.
A team of eight from the Women's Health Research Centre at the University of Otago studied the cases of 29 women admitted to intensive care at Wellington Hospital between 2005 and 2007.
The study - the first of its kind in New Zealand - found that 10 of the 29 cases could have been prevented through earlier action by their midwife or obstetrician.
The main reasons for intensive care were the need for close monitoring and a range of blood-related problems including low or very high pressure, serious blood loss and blood poisoning.
Lead researcher Beverley Lawton says there were some clear patterns and usually more than one person was at fault.
Dr Lawton says she has talked to the Midwifery Council's chief executive and chief adviser about whether there should be more education for midwifes about blood poisoning.
She says the results are probably representative of a wider trend, but only a full national audit could prove it, and is calling for one to be carried out.
Dr Lawton says extending the study to all hospitals would cost about $1 million, but would be money well spent because of the significant health benefits.
"Potentially lives and also the cost of the actual event to the health service is not insubstantial. And what worries me more is the personal cost to the woman and their family of having a very severe illness around about maternity."
Minister supports national study
Health Minister Tony Ryall says the idea of a national study of women who become critically ill during childbirth is a good idea.
Mr Ryall says the Government is already trying to raise the quality and safety of maternity services, including through the work of the Perinatal and Maternity Review Committee.
The minister says he will ask the committee's chair to advise him if there is value in looking more widely and deeply at the issue.
Dr Lawton says she does not mind who picks up the study - as long as it is done.