Signatures are being gathered for a petition to allow babies to sleep in slings at playcentres.
The Otago Playcentre Association started the petition after the Ministry of Education advised playcentres of the ban.
The issue arose when Mike Madden asked Macandrew Bay Playcentre if his baby would be allowed to sleep in a sling.
Mr Madden's partner, Emma Collins, said the ban went against her philosophy.
''It goes against my culture of attachment parenting,'' Ms Collins said.
''Being a member of the Dunedin Baby Wearing Group taught me safe ways to wear a baby.
''They're not really providing a solution to accommodate us.''
Playcentres require a parent to be with their child for the session until they are aged 3, so some parents carry their baby in a sling.
Association member Vicky Brown said the playcentre sought clarification on sleeping rules from the ministry.
''We were told [by a Ministry of Education adviser] that in no uncertain terms, the baby had to lie flat.''
The rule is in place to ensure a baby is able to breathe adequately while sleeping.
The ministry's sleeping regulations state ''furniture and items'' used for children to sleep need to ensure they lie flat.
Ms Brown said some parents had said they would withdraw their children from Otago playcentres if the regulation continues to be enforced.
''We have three [parents] who said definitely they wouldn't continue and we have three that it currently affects,'' Ms Brown said.
New Zealand Playcentre Federation operations manager Veronica Pitt said playcentres were licensed early childhood centres and ''must follow the regulations given by the Ministry of Education''.
''Parents would be encouraged to lay their child in the provided sleep spaces at playcentre, as these are set up to be safe, quiet and meet all the regulations,'' she said.
There is confusion and conflicting accounts from the ministry about the regulation on ''wearing'' sleeping babies.
''They [the ministry] have said they are not going to enforce it straight away,'' Ms Brown said.
When contacted by the Otago Daily Times, the ministry advised that any baby at a playcentre under the care of its parent could be cared for in a way the parent chose.
Rawiri Brell, the ministry's deputy secretary of early learning, parents and whanau, said the licensing criterion did not apply in this situation.
''When babies are at a playcentre session with their parents they are under the care of their parents ... parents can choose how, or in what, their babies should sleep, just as they would at home.''
Adding to confusion, the advice differed from that given to the association by a local adviser.
The local adviser referred all ODT questions to the ministry.
