The news that the Love Actually star and her Klaxons musician husband James Righton are to become parents comes the day after reports suggested Keira has been avoiding alcohol and wearing more loose fitting clothing than normal.
Keira is officially pregnant with her first child
London-born Keira made a red carpet appearance on Sunday night at the Moet British Independent Film Awards and while she showed no visible signs of a baby bump, the Daily Mail reported Keira "steered clear from any champagne or alcohol" during the evening.
Keira's eagle-eyed fashion fans also suggested that the textured dress she chose for the event was a departure from her more tailored style and its flared skirt wouldn't be figure-hugging.
The British actress, who tied the knot with James in 2013, is believed to be in the first trimester and a source told Page Six that "Keira and her stylist have been putting together looks that hide her growing bump".
Keira and James tied the knot in 2013
2015 will be a memorable year for the 29-year-old star. 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.
On Thursday both Keira and her co-star Benedict Cumberbatch were nominated for SAG Awards for their roles in the Second World War drama.