Ke$ha wrote a song about her vagina with her mother.

Speaking about the song 'Gold Trans Am', the 25-year-old pop star said: "It began as a song about my car, which is a gold Trans Am, and it works about 40 per cent of the time. I don't have another car because I love that one so much. But then like all great pop it became a metaphor for something else - my p***y. But my vagina is in tip top working order. Valeted and souped-up and working 100 per cent of the time."

Ke$ha accepts many people might find the close relationship she has with her mother and the subjects they are willing to discuss together odd but she thinks more people should follow their lead.

In an interview in the new issue of Q magazine, she added: "We write songs about boys and sex together. That may not be normal to the average psychiatrist out there but I think it's pretty cool ... Don't analyse. That's the problem with so much culture out there. People are so trapped into trying to do the right thing. As long as you are not hurting anyone I think you should feel free to indulge your fantasies."