Clarkson is expecting her second child and, while she was scheduled to appear on Idol's farewell season as well as the Grammy Awards, doctors have ordered the pop icon to pick between the two for health reasons.
"I was going to do the Grammys and Idol, and then my doctor was kind of like -- I just have such hard pregnancies, flying back and forth to LA, like if they were closer together, I would've done both, but I had to kind of choose one," Clarkson explained to Ryan Seacrest on his syndicated radio show.
Clarkson, 33, has been nominated for Best Solo Performance for "Heartbeat Song" and Best Pop Vocal Album for Piece by Piece at the Grammys. However, paying tribute to American Idol clearly takes priority this year.
"I obviously chose Idol because it's ending and I was the original winner, so it'd kinda be weird if I wasn't there," Clarkson admitted. "I'm unfortunately going to have to miss the Grammys."
Clarkson made a good point, that Idol is saying goodbye but the Grammys are an annual event.
According to E! News,American Idol's executive producer Trish Kinane announced last month Clarkson would be appearing on Season 15 as a performer and guest judge for its first Top 10 live show. Kinane insisted Clarkson was happy to do it and other Idol alums who made "a huge contribution to the show" would also likely appear.
As for whether Simon Cowell will grace the show with his presence again, Seacrest teased of the original judge, "Simon's hung up on his lighting. We did speak and I think you'll see the original faces back on the show before it's over."