The Countdown presenter posted a photo of herself standing in front of the show’s famous letter board while cradling her baby bump on Instagram on Wednesday.
She captioned the snap: “A special teatime teaser! And your clue is… Riley had this to thank for the reason her clothes no longer fit her… And it’ll only get worse till Autumn!”
“Happy, happy days for our little family @pashakovalev and future big sister Mave,” she added.
The board featured the letters “FITTRILEY”, an anagram of “fertility”.
Rachel and Pasha are already parents to one-year-old Maven Aria.
The couple married in Las Vegas in June 2019, having first met when they were paired up on the 2013 series of Strictly.
Mark Robert Milan via Getty Images
Rachel announced her first pregnancy in a similar way, sharing a photo of herself on the set of the Channel 4 game show, with the letters on the board spelling out “R TINY MATE”.
She wrote: “Pash and I have a conundrum for you… you have till December to work it out! We’re over the moon excited.”