Keira Knightley can't fit into her pre-pregnancy jeans.

The 31-year-old actress, who gave birth to her daughter Edie in May last year, has admitted she refused to give into pressure to get back into shape after delivering the little girl.

Speaking to the December issue of Britain's Harper's Bazaar magazine about her body, the brunette beauty said: ''It's a different body, as it should be, because it's done an extraordinary thing ... I thought I was going to go, 'God, I've got to get back into shape.' I actually went completely the opposite. I went, 'F**k that, I'm not putting that pressure on myself in any way.'

''So it's taken me a long time to get back into my jeans. I'm nearly there. Not quite there, but nearly there.''

And the 'Pirates of the Caribbean' star - who is married to Klaxons musician James Righton - claimed only rich women can afford to go back to work after having children so counts herself ''lucky'' she is able to afford ''really good childcare'' for her tiny tot.

She explained: ''One of the things that is so shocking in this country is that childcare is unbelievably expensive. It's incredibly difficult, it should be well paid. But there is no option for a woman to go back to work unless she's being paid really, really well and can afford full-time care before [her child can] get into nursery.

''I think I've become unbelievably aware of that and how lucky I've been to be able to afford really good childcare, because otherwise it would be at least four years out of my career.

''I wouldn't be able to get back to where I'd been if I'd taken four years out. I think that's the same for most women. And I think that's really hard.''

Although Keira has returned to work, she has hinted her child is a handful and has described her as a ''ballistic missile''.

Speaking about Edie, she said: ''[She is] like a ballistic missile. She's at about a million miles an hour from the second she wakes up to the moment she goes to sleep.''