The pressure on "American Idol" is intense. Singers spend their weeks picking songs, learning them, rehearsing group numbers, doing press and otherwise living in the intense bubble that is the "Idol" universe.

So it's not surprising that sometimes, that strain can get to the contestants, most of whom are performing in front of audiences and cameras for the first time in their lives. The latest singer to go down is Crystal Bowersox, the 24-year-old Ohio busker and mother of one who was hospitalized Tuesday and ordered by doctors not to perform as scheduled on that night's show. That led to a rare lineup shuffle, forcing the men to perform Tuesday night as Bowersox rested up for Wednesday night's (March 3) show.

"Due to medical issues which would prevent Crystal Bowersox from performing tonight, the 10 male semifinalists will perform this evening, and the 10 female semifinalists will perform tomorrow night," read a statement from the show on Tuesday.

An unnamed source told Us Weekly that Bowersox is recovering from diabetes complications and is expected to be well enough to perform Wednesday.

The Los Angeles Times reported that Bowersox is believed to be diabetic, but a spokesperson for the show did not return requests for comment on the singer's current condition or what ailment laid her up. No contestant has ever taken a medical leave of absence from "Idol" to date. The Times reported that a contestant on the U.K.'s "Pop Idol," Rik Waller, was allowed to take a week off to recover from a throat infection, but "Idol" executive producer Ken Warwick said during a radio interview Wednesday that if Bowersox can't perform, she will be off the show.

Health issues have stricken "Idol" contestants since the first season, when sixth-place finisher Christina Christian spent the night in the hospital on the night she was eliminated while suffering from dehydration, fatigue and exhaustion. That season's fifth-place finisher, RJ Helton, was injured during his run on the show, falling off the stage onto his back on a Tuesday night and leaving the studio in a wheelchair, only to return the next night.

Back in season seven, eventual winner David Cook was rushed to Los Angeles' Cedars-Sinai Medical Center for high blood pressure and heart palpitations after reportedly collapsing during the competition. He was encouraged to go to the hospital earlier in the night but stuck around until the Dolly Parton-themed hour ended. Cook already suffered from high blood pressure before trying out for "Idol." The singer reportedly collapsed during an earlier show that season but stuck around to perform that night as well.

Season seven also saw a bad bout of the stomach flu hit some of the female competitors, most prominently Carly Smithson, who also battled bronchitis, but fought back to earn some of her best critiques of the season.

Last year, Utah native Megan Joy was also nearly taken out with a nasty case of the flu, coughing audibly after singing Patsy Cline's "Walking After Midnight," with the judges giving her props for soldiering on through her illness.

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