A new study of pregnant indigenous women in four countries suggests the stigma around smoking in pregnancy was stopping Māori women from accepting help to quit.
The study across New Zealand, Australia, the United States and Canada, has found that a quarter of Māori women who smoke continue to do so throughout pregnancy compared with 15 percent of non-Māori.
The prevalence of smoking while pregnant varied across states and countries, ranging from 18 to 83 percent for Inuit women.
In Australia, 48 percent of Aboriginal women who smoked continued to do so during pregnancy, while that figure was just 13 percent for non-Indigenous Australian women.
The study's New Zealand co-author, Associate Professor Marewa Glover from Massey University's School of Public Health, said the stigmatising approach used in tobacco control was making some Māori women hide the fact they could not give up.
"It is stopping them from coming forward for help. Some find the judgemental attitude that they are confronted with when they say they smoke is unacceptable and they just back away from care."
Dr Glover said the Ministry of Health needed to make pregnant Māori a priority for targeting resources and more research was needed into vaping as an alternative.
"Despite our cultural differences, the indigenous people in each country experience similar marginalisation and social disadvantage," she said. "This stems partly from the common way in which we were colonised by Western nation states."
"That colonization process resulted in indigenous people receiving proportionately less of society's benefits, whether that's education, healthcare or employment.
"Our women are disproportionately exposed to environmental risks to health, discrimination and disproportionate incarceration.
"We are over-represented among the lower paid and unemployed and are more likely to live in deprived areas. The cumulative stress of all this is driving our higher smoking rates and undermining our women's ability to abstain from smoking, even when they are pregnant," Dr Glover said.
The study was looking for successful intervention ideas they could share.
The researchers wanted to see indigenous-led and culturally-based programmes funded, such as services that fund indigenous elders and community health care providers to work with families.