Piper married actor Laurence Fox in December
Actress Billie Piper has said she has not decided about whether to return as Rose in the next series of Doctor Who.
Piper told The Radio Times: "I haven't thought about it," adding "at some point you've just got to let go".
The actress, who is expecting her first child with actor husband Laurence Fox, said that motherhood is her priority over "the rest of my career".
She also denied having speech problems in recent Doctor Who episodes, blaming it on filming in cold weather.
"It seemed fine when I heard it. When I went to work the next morning the make-up guy said, 'Your speech sounded really funny.' I wonder whether it was something in the final mix. Strange," said Piper.
Speaking about her role in Doctor Who, the actress said that it is "stressful when the schools are out".
"Sweet as they are, kids en masse are kind of frightening. Every child just thinks you're Rose and you don't want to spoil the illusion," she said.
Piper won two National Television Awards for her role as Rose Tyler, who teamed up with Christopher Eccleston's Doctor when the series was revived in 2005.
The actress, who is about to star in the second series of Secret Diary of a Call Girl, rubbished claims that she is about to crack Hollywood.
"I don't get too carried away. I've had calls from agents, but you still have to go and audition - they don't just happen," she said.