The new arrival is her first child with partner David Oakes. She was born in January but the pair have kept her birth private until now, only sharing the happy news with family and close friends.
The 39-year-old revealed the news of her “Covid baby” on Esther Rantzen’s podcast That’s After Life.
Dormer said: “It’s the perfect thing to do during a pandemic - get pregnant, have a baby.”
The actor played Margaery Tyrell in multiple seasons of the hugely loved TV show Game of Thrones. Her partner, Oakes, is also an actor and the two met while performing a West End play.
Speaking about her pregnancy, Dormer suspected she is among many people who will have had babies during lockdown.
She continued: “I feel like I’m probably being a bit of a cliché, she’ll probably be sitting in a bar in 30 years’ time one day going, ‘Yeah, I’m a Covid baby’.
“I think there’s going to be lots of Covid babies because what else can people do, maybe like Blitz babies?”
Dormer spoke about how motherhood has changed her in just a few months.
She said: “She’s just three months and she’s an absolute joy, I’m never going to complain about shooting hours ever again because sleep deprivation is something else.
“People say, ‘Your whole perspective on life will change, and your whole set of value system’ and you sort of roll your eyes and go ‘yeah, yeah’ - and then you have one and you go, ‘Oh. Wow!’”
The star admitted the only thing she is not enjoying about new motherhood is the lack of sleep.
She continued: “I’m in love. I’m absolutely in love, she’s a joy. Sleep has always been quite important to me - that’s the only downside.”
The star believes returning to filming TV or films would be difficult with a baby, but hoped that a return to the stage would be more manageable, whenever that may be due to the pandemic.
She explained: “I mean for me, this is the perfect time to go back to the stage, because then I could be with her all day.
“But with Covid who knows when that will happen. I really feel for our theatres around the country, there’s hard times.”
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