The Labour Party says there is less money in the latest Budget to pay midwives who work as lead maternity carers.
It also says primary health care gets little extra.
Health has received a funding increase in the Budget, to a total of $14.7 billion.
But Labour health spokesperson Annette King says annual funding for lead maternity carers under a policy known as Section 88 has been reduced from $147 million to $144 million.
She says it appears to be based on an assumption that 70% of women giving birth have a lead maternity carer, when more than 90% do.
"I've no idea why they think fewer women are needing a lead maternity carer than in the past. In fact it's the opposite but also there has been no pay rise for lead maternity carers for six years now."
Ms King says with the exception of a very low cost access scheme, primary healthcare will also receive very little extra funding through the Budget.