The news of Leslie’s pregnancy was revealed on Saturday, when a photo of the actor taken for a magazine interview was shared on Instagram.
The picture, from digital publication Make Magazine, featured Leslie smiling with her hands placed on her hips as she showed off her growing baby bump.
Sharing the image on her personal account, fashion editor Ursula Lake wrote: “A very special all woman team photographic shoot capturing Rose at this wonderful time as she prepares for motherhood for the first time!”
In the accompanying interview, Leslie spoke about the couple’s home in the English countryside, saying she was looking forward to raising a family there, after years of living in New York.
“What a glorious thing to be able to run to the countryside and recoup,” she said.
“It’s a great privilege to be surrounded by greenery, birdsong and hedgerows, and our delightful neighbours. It’s so peaceful.”
The couple played Ygritte and Jon Snow in HBO series Game of Thrones, in which they also had an on-screen relationship.
In the show, 33-year-old Leslie’s character became known for the phrase: “You know nothing, Jon Snow.”
The wedding took place at her family’s castle in Wardhill, Aberdeenshire, with former co-stars Maisie Williams, Peter Dinklage, Emilia Clarke and Sophie Turner all in attendance.
The. couple took the traditional step of announcing their engagement in The Times.
The announcement said: “The engagement is announced between Kit, younger son of David and Deborah Harington of Worcestershire, and Rose, middle daughter of Sebastian and Candy Leslie of Aberdeenshire.”