The Imitation Game star welcomed her first child with rocker husband James Righton in the spring (15), and the British actress is only now opening up about the arrival of the tot, which the couple has named Edie.

In her first interview since the birth, Knightley tells Elle magazine, "The love thing is astonishing. It's a very primal, primal love. That's quite extraordinary. And the ability to have no sleep and continue going. It's not pleasant - I never thought that I could actually do it for the amount of time that I've done it."

She continues, "Also, I have to say, as a woman, you hate certain parts of your body. You go through those periods where you look in the mirror and you think, 'Oh, if only I had different legs or arms or whatever'. You go through pregnancy and labour and then feeding the kid and you go, 'Wow, my body is totally amazing, and I'm never going to not like it again, because it did this, and this is f**king extraordinary'."

Knightley, who turned 30 in March (15), goes on to admit she is glad to have finally bid farewell to her 20s, because although her career was soaring, she struggled with insecurities in her personal life.

She explains, "My 20s were pretty crap. My career was absolutely amazing; in fact, I don't think my career will ever get better than it was in my late teens, early 20s. But as a person, you're changing so much and you're trying to figure stuff out. Some people go wild and have a great time and throw caution to the wind, and I was the complete opposite.

"I was very shy. It took me a lot of years to try and stop pleasing a lot of people and allow myself to have fun. It's the difficult thing of getting out of your own head. To stop going, 'Oh, there's something I should be doing, there's a way I should be behaving, I should be dressing...' All of those 'shoulds', you can drown in them."

The actress learned to deal with her issues in therapy, and she is a big fan of the treatment, declaring, "I highly recommend it. I don't do it at the moment. But in my early 20s when I found everything completely overwhelming, 100 per cent, I did it...!

"I think when you're in those moments in your life, and you want to get through them... you have to do whatever it is to help you get over it. You have to give it a go. Try anything that might help."