On Thursday, New Zealand Prime Minister Jacinda Ardern gave birth to her first child, a girl weighing 7.3 pounds. Ardern worked late into her pregnancy and delivered at Auckland Hospital, the country's largest public hospital.
Deputy Prime Minister Winston Peters has stepped in as acting prime minister. He will assume Ardern's responsibilities for the next six weeks while she takes maternity leave. She is the first world leader to take maternity leave while in office.
"Welcome to our village, wee one," wrote Ardern in an Instagram post. "Thank you so much for your best wishes and your kindness. We're all doing really well thanks to the wonderful team at Auckland City Hospital."
Ardern is not the first world leader to be pregnant while in office — Benazir Bhutto gave birth while she was Prime Minister of Pakistan — but she is one of few. In fact, she is one few women to serve as head of state overall. Just 38 percent of the 148 countries studied by the World Economic Forum in 2014 and 2016 have had a female head of government or state for at least one year in the past half-century.
Ardern's story is also remarkable for the support she has received from her male colleagues and family members.
In January, Ardern announced that she and her partner Clarke Gayford were expecting. "We're excited and we know together that we are going to make this work and New Zealand is going to help us raise our first child," she told reporters.
In an Instagram post, she added that Gayford, who hosts a television show about fishing, "will be 'first man of fishing' and stay-at-home dad."
In 2017, New Zealand Parliment voted to extend paid parental leave entitlement from 18 weeks to 22 weeks. Ardern will take only six.
"I am by no means the first woman to multitask," she told reporters outside her Aukland home in January. "And in terms of being a woman in politics, there are plenty of women who carved a path and incrementally have led the way to be able to make it possible for people to look upon my time in leadership and think, 'Yes, I can do the job and be a mother.'"
Ardern is New Zealand's third female Prime Minister, following Jenny Shipley and Helen Clark. She told reporters that she realized she was pregnant just six days before she took office on October 26th, 2017.
Previously that year, when Ardern was serving as the leader of New Zealand's Labour Party, she repeatedly faced questions about her plans to have children.
On the radio program "The AM Show," former cricket player Mark Richardson asked, "Is it OK for a PM to take maternity leave while in office?" He insisted that it was a "legitimate question" and added that employers should have the right to know if an employee plans to have children.
Ardern said she was personally open to answering questions about her plans but said that it was inappropriate to suggest that other female employees should be expected to do the same. "For other women, it is totally unacceptable in 2017 to say that women should have to answer that question in the workplace," Ardern told Richardson. "It is a women's decision about when they choose to have children. It should not predetermine whether or not they are given a job."
Arden added, "I think a lot of women face this dilemma in the workplace no matter what their profession or job might be."
Prime Minister Arden also reiterated that many women before her have done what she plans to do. "I'm not the first woman to work and have a baby," she said. "I know these are special circumstances but they'll be many women who will have done this well before I have. I acknowledge those women."
This is an updated version of a previously published article.
Like this story? Subscribe to CNBC Make It on YouTube!