Mums with babies aged under six months old could see the advertising of infant formula aimed at their children dropped, following a proposal backed by the Commerce Commission.
In November the Infant Nutrition Council (INC), which represents manufacturers, marketers and importers of infant formula, applied to the Commission to authorise its current voluntary Code of Practice, which restricts its members from marketing and advertising formula for babies under six months old.
Manufacturers would also not be allowed to give free samples to pregnant women and mother, or distribute samples to healthcare professionals as a sales inducement.
Formula for older babies and toddlers could still be advertised.
The Commission has released a preliminary decision authorising the practice, which follows an international voluntary code already set by the World Health Organisation.
Chairman Dr Mark Berry said restrictions on marketing and advertising activities typically limited the amount of information available to consumers, reducing competitive pressure and making consumers worse off.
"In this instance, however, authorising the INC's Code of Practice is likely to have significant public health benefits," he said.
"In particular, it is widely agreed that there are a variety of health benefits from breastfeeding, which could be adversely affected by the unrestricted marketing and advertising of infant formula."
Dr Berry added that authorising the Code of Practice was unlikely to impact the price of infant formula.
INC chief executive Jan Carey said the Commission's approval would ensure members, who cover the Karicare, Nurture and S-26 brands in New Zealand, complied with the code.
Ms Carey said the council supported breastfeeding as optimal for baby and infant formula as the next best substitute.
But she said there was a misconception in New Zealand that the Code of Practice was to solely promote breastfeeding when it was actually aimed at promoting adequate nutrition for babies.
"That includes supporting breastfeeding but also providing information about formula feeding when necessary."