Reality television star Kim Kardashian gave birth to a baby girl on Saturday, her first child with rapper boyfriend Kanye West, news reports said.

Kardashian, 32, was admitted to Cedars-Sinai Medical Center in Beverly Hills five weeks ahead of her due date and delivered a baby girl, the entertainment news website TMZ.com reported.

The website said West was present at the birth and had cancelled an event to promote his new album late Friday after Kardashian had complained of feeling a "little off."

US Magazine quoted a hospital source as saying the Kardashian and her daughter were "doing great and amazing!".

"Kim had her baby," the source was quoted as saying. "She's five weeks early. Kim got sick last night and had the baby early."

Kardashian announced her pregnancy on New Year's Eve last year following her whirlwind romance with West.

"Looking forward to great new beginnings in 2013 and to starting a family. Happy New Year!!! Xo," Kardashian wrote in a blog.

Kardashian shot to notoriety in 2007 after the emergence of a home sex video featuring her and her then boyfriend, the singer Ray J, filmed several years earlier.

She later became the star of the reality series "Keeping Up With the Kardashians", which centred around the lives of her and her Los Angeles-based family.