"Officers attended along with the LAS and found the woman, aged 26, suffering from stab injuries.
"It was also established that she was approximately eight months pregnant. Despite the efforts of paramedics, the victim sadly died at the scene.
"Her baby was delivered at the scene before being taken to hospital. The child (we are not confirming gender at this stage) remains there in a critical condition."
Detective Chief Inspector Mick Norman, who is leading the investigation, said: "This is a horrific incident in which a young mother has lost her life and her child is critically ill.
"Our sympathies go out to her devastated family; they are being supported by specially trained officers following this awful event, and I would ask that they are left alone at this time as they come to terms with the enormity of what has happened."
London mayor Sadiq Khan tweeted: "Violence against women is endemic in society and devastating murders in the home, like this one, show the scale of the problem we face.
"My prayers are with this innocent child, and with the mother it has so tragically lost."
-The Telegraph