Christina Aguilera's children weren't ''planned''.

The 'Genie in a Bottle' hitmaker has son Max, 11, from her relationship with Jordan Bratman and five-year-old daughter Summer with Matthew Rutler and has admitted neither of her kids were thought out before they were conceived because she likes to be ''spontaneous'' when it comes to making babies.

Speaking to Haute Living magazine, the 38-year-old pop star said: ''You know, it's funny - even the children I have had, I haven't necessarily planned! I'm very spontaneous when it comes to that. What the universe thinks will be, will be. Who knows what's in the future? But, as of now, [I'm not planning on having more kids].''

And, although she hadn't planned to have children when she did, she believes her life changed for the better once they were born because it shifted her ''focus.''

She explained: ''It just shifts your focus so much when you have a child. In business, in general, and as an artist, you're in a sea of extreme narcissism. It is your focus. You are your work, your focus and goals. Being a very ambitious girl at a very young age and having worked my whole life, [having my kids] was a time where it wasn't about [me] anymore.

''I couldn't wait for that, to be honest. I was a very young mom. I'm a huge kid at heart, and they give me the opportunity to play and be able to instil and encourage their imaginations. You're part of these amazing little people's lives, and it teaches you patience and teaches you things about yourself that you don't like, that you want to work on. It's a constant journey of learning. They teach me so much and they challenge me all the time to be better.''