In a pre-recorded broadcast taped at Buckingham Palace, the queen said a new baby brings "happiness and hope," the Guardian reported.
Alluding to the birth of her great-grandson Prince George, she said, "here at home my own family is a little larger this Christmas."
"As so many of you will know, the arrival of a baby gives everyone the chance to contemplate the future with renewed happiness and hope," the queen added. "For the new parents, life will never be quite the same again."
As the message was broadcast, many members of the royal family gathered at Sandringham, the queen's estate in Norfolk. Prince George was kept inside to stay warm, so he was not seen by the 3,000 well-wishers who gathered outside.
A woman who inquired about the baby from his mother, Kate Middleton, the Duchess of Cambridge, said she was told "he was having a good day but was more interested in the wrapping paper than the presents."