Jacinda Ardern took her baby to the UN, like it's no big deal.

It’s been a year since New Zealand held the elections that swept Jacinda Ardern into top office. At 37, she was the country’s youngest Prime Minister in 150 years, the youngest female leader anywhere in the world and with the arrival of her daughter in June, she became only the second world leader to give birth while in office.

And this week, another milestone.

The Labour Party leader took her three-month-old baby, Neve Te Aroha, to the United Nations; the first female world leader to bring an infant to a meeting of the General Assembly.

Baby Neve watched on from the lap of her father, fishing show host Clarke Gayford, as Prime Minister Ardern delivered a speech at the Nelson Mandela peace summit.

She then had kisses with her mum when the leader returned to her seat.

Gayford later tweeted a photograph of Neve's United Nations ID, which came complete with a photo and the very official title of "First Baby".

He also shared details of a rather awkward nappy change incident.

"I wish I could have captured the startled look on a Japanese delegation inside [the] UN yesterday who walked into a meeting room in the middle of a nappy change," he wrote. "Great yarn for her 21st."

Because everyone on twitter's been asking to see Neve's UN id, staff here whipped one up.
I wish I could have captured the startled look on a Japanese delegation inside UN yesterday who walked into a meeting room in the middle of a nappy change.
Great yarn for her 21st. pic.twitter.com/838BI96VYX

— Clarke Gayford (@NZClarke) September 24, 2018

Prime Minister Ardern, who is still breastfeeding, chose to bring Neve on the six-day trip, but has stressed that Gayford is travelling at the family's own expense.

“There is no spousal programme for this, so we just made a judgement call that we would cover his travel for this trip. He will be going to some things, but he’s primarily travelling to care for Neve,” she told The New Zealand Herald.

Whether or not he and Neve will attend any official functions with Prime Minister Ardern in New York depends, she said, on "what the jet lag does to them both".

“She’s a good sleeper and we don’t know whether that will mean she ends up sleeping a lot in the day rather than the night,” she said.

Speaking during a panel discussion at Unicef’s social good summit in New York this week, Prime Minister Ardern noted that she is in a privileged position that allows her to raise a child and maintain a high-level job.

“I have the ability to take my child to work, there’s not many places you can do that. I am not the gold standard for bringing up a child in this current environment because there are things about my circumstances that are not the same,” Ardern said.

“If I can do one thing, and that is change the way we think about these things, then I will pleased we have achieved something."