The admission came in an exclusive interview with Access Hollywood host Billy Bush on TODAY, which aired Thursday morning.
Since her surprise wedding two years ago to America’s Got Talent host Nick Cannon, the media has regularly speculated about whether Carey was pregnant.
But it was only last week that the couple decided to go public with their happy news, to coincide with the release of Carey’s album “Merry Christmas 2 U”.
“It’s been a long journey, but it’s been tough because I’ve been trying to have ... to hold onto a shred of privacy. And that was not easy,” Carey told Bush.
The 40-year-old star wouldn’t specify exactly when the baby is due, except to say in the spring.
Cannon, who joined the interview partway through, revealed the tough time the couple had two years ago when Carey had a miscarriage.
“Her strength would literally be during the day so festive and smiling obviously for cameras and spending time with everyone and you know, literally that night crying herself to sleep,” Cannon said.
Bush said that Mariah and Cannon had conceived naturally and didn’t want to find out what sex the baby was in advance.