Kidman has adopted children Isabella, 27, and Connor, 24, with ex-husband Tom Cruise and daughters Sunday, 11 and Faith, nine, with spouse Keith Urban.
She said: "I'm glad that when I got pregnant with Sunny, I didn't give everything up. Because I was like, 'That's it, I'm done now.' I was in that sort of pregnancy euphoria going, 'Yes this is it - I'm retiring.'
"My mom actually said, 'Don't do that. Just keep a little toe in the water."
The "Moulin Rouge!" actress is happy with her decision but wishes she had "more time" so she could give her family the attention she needs while also being able to take on all the creative projects that interest her.
She told heat magazine: "I do wish I had more time. I have two little girls and I have a husband who I am deeply in love with - a cool guy and a good man - and we have a very strong family unit that requires an enormous amount of time.
"So, I don't have all the chances to go and support all the artistic endeavours I would love to do. I want my family and I want the balance."
The "Bombshell" star said her husband gives her the "balance" in her life she's always craved.
She said: "I like to relax by meditating but what makes me feel most comfortable and secure is being with Keith. Having a partner by your side, someone you can talk with, who loves you and whom you love, balances everything.
"Before I met him, I was more scared. Now I feel protected thanks to this great friend and wonderful partner I have."
( With inputs from IANS )