Amanda Holden is recovering after a car accident in west London.
The pregnant Britain's Got Talent judge is said to have been left "shaken" by the bump, but she and the baby are understood to be "fine".
Holden, 40, was heading on the school run to collect her daughter Lexi, five. She collided with a lorry and was taken to hospital for a check-up by a passing stranger.
A spokeswoman for the actress said: "The lorry's fine, Amanda's car isn't."
Holden has had to pull out of Wednesday's performance of West End hit Shrek The Musical - in which she plays Princess Fiona - as she is recovering.
The spokeswoman said: "Amanda is so grateful to her good Samaritan."
Holden announced a fortnight ago that she is pregnant. She lost a baby earlier this year seven months into the pregnancy.
Holden and her husband Chris Hughes also went through the ordeal of a miscarriage the previous year.