Boris Johnson and Carrie are expecting a second baby.
The couple welcomed their first child together Wilfred in April last year.
Now Mrs Johnson, 33, has told her friends she felt “incredibly blessed” to be pregnant again in an Instagram post over the weekend.
She also said the brother or sister to Wilfred would arrive at “this Christmas”.
The Prime Minister’s wife also opened up about her heartache after suffering a miscarriage at the start of the year.
She wrote on Instagram: “At the beginning of the year, I had a miscarriage which left me heartbroken. I feel incredibly blessed to be pregnant again but I’ve also felt like a bag of nerves.
“Fertility issues can be really hard for many people, particularly when on platforms like Instagram it can look like everything is only ever going well.
“I found it a real comfort to hear from people who had also experienced loss so I hope that in some very small way sharing this might help others too.”
Mr Johnson became the first prime minister to marry in office since Lord Liverpool married Mary Chester in 1822.
Their first son Wilfred was named after Mr Johnson’s grandfather, Lawrie after Mrs Johnson’s grandfather, Nicholas after Dr Nick Price and Dr Nick Hart – the two doctors that saved Mr Johnson’s life during his Covid battle.
At the time, she wrote in her Instagram post announcing Wilfred’s birth: “Introducing Wilfred Lawrie Nicholas Johnson born on 29.04.20 at 9am.
“Wilfred after Boris’s grandfather, Lawrie after my grandfather, Nicholas after Dr Nick Price and Dr Nick Hart – the two doctors that saved Boris’s life last month.
“Thank you so, so much to the incredible NHS maternity team at UCLH that looked after us so well. I couldn’t be happier. My heart is full.”