Keira Knightley and husband James Righton at the BIFAs
The couple, who married in 2013, are said to be past the first trimester and a source told Page Six that "Keira and her stylist have been putting together looks that hide her growing bump".
2015 will shape up to be a busy year for the 29-year-old British actress; not only will she be preparing to welcome her first child, she is also expected to hit the awards circuit with her latest film The Imitation Game with Benedict Cumberbatch.
This week, the pair were both nominated for SAG Awards - an important indication for the upcoming Oscars - for their roles in the Second World War drama.
Keira Knightley with Benedict Cumberbatch in The Imitation Game
Keira has been vocal about her desire to start a family in the past, but revealed earlier this year that she would not encourage her children to enter her profession.
The actress admitted she would advise any daughter of hers to avoid a life of "heartbreaking" rejection, and instead choose a different career. "I should imagine that if she wanted to act, I wouldn't have a choice but, no, I certainly wouldn't recommend it," said Keira.
"It can be completely heartbreaking for most people who do it, because the amount of rejection is enormous. And it doesn't matter what kind of person you are, it's impossible for that not to take a toll…
"So I would say to my daughter, 'Be a doctor or a lawyer – something stable and useful'."