Taking to social media on Friday, Ms Ardern announced that she and her partner, Clarke Gayford, were expecting their first child.
“And we thought 2017 was a big year! Clarke and I are really excited that in June our team will expand from two to three, and that we’ll be joining the many parents out there who wear two hats," Ardern wrote on Facebook and Instagram.
"I’ll be Prime Minister AND a mum, and Clarke will be “first man of fishing” and stay at home dad."
The New Zealand leader added: "I think it’s fair to say that this will be a wee one that a village will raise, but we couldn’t be more excited. I know there will be lots of questions, and we’ll answer all of them (I can assure you we have a plan all ready to go!) But for now, bring on 2018."
In October, the 37-year-old Labour Party leader was announced as New Zealand's Prime Minister, the second youngest PM in the country's history.
This article originally appeared on marie claire.