Britney Spears has revealed her second pregnancy was an accident.

However, the Toxic singer - who already has one son, 11-month-old Sean Preston, with husband Kevin Federline - insists she is looking forward to being a mum again.

She confessed to People magazine: "It just kind of happened. I'm going to wait a while for the next one!

"I feel like I've been pregnant for ten years!"

Britney - who is rumoured to have put on around 40 pounds during her pregnancy - also revealed how having back-to-back babies has been an exhausting experience.

The 24-year-old star explained: "It is now starting to get a little tiring, holding Sean Preston, but throughout the whole pregnancy I've done it a lot because he's very attached.

"It makes me feel needed and wanted so I like it too."

AdvertisementAdvertisementBritney has also confessed her favourite pregnancy treat - a melted chocolate bar.

She confessed: "I'll get up in the middle of the night and I'll get a Hershey's bar, the real big ones, and I'll put it in the microwave and melt it and eat it.

"It sounds disgusting, but it's so satisfying."