In an official statement on Friday, Ardern spoke of the joy of she and her partner Clarke Gayford.
“We’re both really happy. We wanted a family but weren’t sure it would happen for us, which has made this news unexpected but exciting,” she said.
Deputy Prime Minister Winston Peters will take on the top job for six weeks after the baby is born.
“As is the case when I am overseas, Mr Peters will act as prime minister, working with my office while staying in touch with me. I fully intend to be contactable and available throughout the six week period when needed,” Ardern said.
“At the end of my leave I will resume all prime ministerial duties.”
The couple found out on October 13 – in the midst of negotiations over who would form the new government – but had kept it quiet as was common in the early stages of pregnancy, she said.
Ardern said she and Gayford were privileged enough to allow him to stay at home as primary caregiver.
“Knowing that so many parents juggle the care of their new babies, we consider ourselves to be very lucky.”
We thought 2017 was a big year! This year we’ll join the many parents who wear two hats. I’ll be PM & a mum while Clarke will be “first man of fishing” & stay at home dad. There will be lots of questions (I can assure you we have a plan all ready to go!) but for now bring on 2018 pic.twitter.com/nowAYOhAbF
— Jacinda Ardern (@jacindaardern) January 18, 2018
The couple received congratulations from across the political spectrum following the announcement – including from former NZ prime ministers Bill English and Helen Clark – and prompted more than 40,000 tweets in an hour.
Australian Prime Minister Malcolm Turnbull called Ardern to congratulate her.
“When we spoke this morning you sounded more excited than you did when you won the election! Lots of love and best wishes from me and Lucy and all of us across the ditch,” Turnbull tweeted.
Ardern is not the first world leader to be pregnant. Pakistan’s Benazir Bhutto gave birth while in office in 1990.
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