"But if it's from a company or something, no. We either say, can I donate it to someone else or just send it back."
Amid all the gifts she's received, it's the little hand-knitted booties she loves the most.
"Some of them are just extraordinary. The amount of detail people have put into these little things is so lovely. And I'll make sure other people get use out of them too."
While the Labour party has pushed to extend maternity leave, the ZM hosts highlight there's some irony in Ardern's plan to get back to work after six weeks.
She tells them she accepts she is in "a different set of circumstances".
"I've been a big supporter of 26 weeks maternity leave. But I'm the only one in the country doing this job. I do think it's a bit different for me."
She says she's lucky that Gayford is able to take time out from work to be a stay-at-home dad and says she has enough space that "no one's going to mind if there's a crib in the corner... I can make it work as well."
She says Gayford, who hosts Fish of the Day, has already looked in to how old the baby will have to be before it can be taken fishing too.
"It's quite hard to get quite miniature life jackets so I think that's the only thing holding him back.
"I have no doubt he'll say, stuff putting it in the back of the car and driving around. I'm just going to take a blat around the Hauraki gulf.
"I told someone Clarke wanted to build a deck while we're at home [with their newborn] and I was surrounded by laughter from the parents."
Ardern is due to give birth on June 17.
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