More midwives are currently being investigated for serious mistakes than any other medical profession.
The latest report from the Health and Disability Commissioner shows investigations into mistakes made by midwives is three times the number for nurses.
"The nature of the environment is that ... we can see very serious harm because when things go wrong they can go badly wrong. So it's not a surprise to see complaints in midwifery appearing in the senior and serious end of the scale," Commissioner Anthony Hill told RNZ's Catherine Hutton.
But Jenn Hooper who heads charity Action to Improve Maternity says the report shows there's a problem.
"If it really is a matter of the nature of the beast and this is the potential outcome, explain to me how come so many breaches are upheld in that sector, because breaches don't come unless there's substandard care."