The caucus is the first time the MPs would have gathered this year and Ms Ardern said there were still several policies she wanted to put in place as part of the government's first 100 days plan. "Obviously, I take very seriously the role of becoming a mum, as does Clarke becoming a dad, but we equally take seriously the role I've taken on as prime minister of New Zealand".
Ardern, 37, became New Zealand's youngest prime minister since 1856 when she formed a centre-left coalition in October. "It's been a long time to carry that secret", she said.
Ardern took to Twitter to announce that she and her partner Clarke Gayford were expecting a child, and that Gayford would become a stay-at-home dad. "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".
New Zealanders of all political persuasions welcomed the news yesterday that Jacinda Ardern is expecting a baby in June. "I know these are special circumstances, but they are many women who would have done this well before I have". Ardern also said that anyone who was anxious about whether her pregnancy will interfere with her job should understand that that no one realized she was suffering from "pretty bad" morning sickness at the very time she was putting together a coalition government.
Ardern took over the Labour leadership in July.
"It is a woman's decision about when they choose to have children and it should not predetermine whether or not they are given a job or have job opportunities", she said.
In 1990, Benazir Bhutto gave birth to a daughter while serving as Pakistan's prime minister, in what was reported to be a first for an elected world leader.
"An important first (as far as I know)".
The 37-year-old anxious her staff might notice she was eating constantly, and only the same foods. She is thought to be the first modern head of government to give birth while in office.
The prime minister's announcement was met with good wishes from at least two former New Zealand prime ministers.
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