"The best countries to have a baby are Norway, Finland and Iceland but their healthcare models are not fundamentally different than yours. You should be in the top 10," she said.
Prof Geller took part in a maternity research project in Wellington led by the University of Otago's Women's Health Research Centre.
She found some women faced barriers when trying to access good quality maternity services.
This was particularly true for Maori and Pacific Island families.
In 2011, the infant mortality rate for Maori and Pacific babies in the Auckland region was more than 2.5 times the rate for babies of other ethnic groups.
"We see inequities in America all the time," said Prof Geller.
"Black women in the US are four to five times more likely to die during childbirth.
"That is because we know access to quality care is based on who you are and where you live."
New Zealand may be facing similar problems with inequality among mothers, she said.
A University of Otago study co-authored by Prof Geller last year found as many as 40 per cent of cases where pregnant women were admitted to intensive care units due to severe illness could have been prevented.
The preventable illnesses were most commonly blood loss and septicemia.
These were often not identified properly due to a failure to recognise a woman's high risk status, said lead researcher Dr Bev Lawton.
Delayed or inappropriate treatment was also a factor.
To find solutions to inadequacies in maternal care, researchers would be measuring severe acute maternal morbidity rates nationwide and exploring changes to clinical behaviour and systems to reduce harm.
