Jamie Lynn Spears has revealed she's pregnant at the age of 16.

The Nickelodeon TV star and younger sister of Britney announced the news in a celebrity magazine.

In the interview, she said she was "shocked" to learn she was expecting after taking a home pregnancy test. It was later confirmed by the family doctor.

The actress, who is three months pregnant by her high school sweetheart, Casey Aldridge, said she kept the news a secret for two weeks but eventually told her mother, who she said has been "very supportive".

"She was very upset because it wasn't what she expected at all," Spears said. "A week after, she had time to cope with it and became very supportive."

Spears also told the magazine that she plans to raise the baby in her home state of Louisiana.

As for how the news will affect the star's role in the show Zoey 101, Nickelodeon said in a statement: "We respect Jamie Lynn's decision to take responsibility in this sensitive and personal situation.

"We know this is a very difficult time for her and her family, and our primary concern right now is for Jamie Lynn's well being."

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