Te Papa is asking pregnant or menstruating women not to visit a behind-the-scenes exhibit at the museum out of respect for Maori beliefs.
The request is being made to women from regional museums who will be going on a back-of-the-house tour of some of Te Papa's collections, including the Taonga Maori collection, Te Papa spokeswoman Jane Keig said.
The Taonga Maori collection is not open to the general public and the request does not apply to them.
Ms Keig said the issue was a "cultural consideration" to respect Maori beliefs.
"There are items within that collection that have been used in sacred rituals. That rule is in place with consideration for both the safety of the taonga and the women," Keig said.
She said there was a belief that each taonga had its own wairua, or spirit, inside it.
"Pregnant women are sacred and the policy is in place to protect women from these objects."
"If they understand that they can attend at another time [when they are not pregnant or menstruating]."
She said the request was made to women attending a tour on November 5.
Margaret Mutu, head of Maori Studies at Auckland University, said women should not be offended by the request.
"The reproduction area is extremely powerful and can do damage to things that are not tapu. It's about the power of women, not about stopping them."
Mutu said the objects were obviously dangerous and the hapu they came from would have told the museum about how to treat them.
"They are tapu and pregnant or menstruating women are tapu. It would be very unwise to put the two up against each other."
Mutu said in her hapu, women were also prevented from going onto gardens or fishing areas while tapu.
Arts, Culture and Heritage Minister Chris Finlayson downplayed concerns, saying he did not get involved in the day-to-day running of Te Papa, but he understood the message was not an instruction.
''It's an advisory requested by the iwi, but it's for people to make up their own minds,'' he said.
- with additional reporting by Stuff and NZPA
- The Dominion Post
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