Nicole Kidman was ''desperate'' to have children of her own before meeting Keith Urban.

The 51-year-old actress has adopted children Isabella, 26, and Connor, 24, with ex-husband Tom Cruise, and biological children Sunday, 10, and Faith, eight, with spouse Keith, and has said that before meeting the musician and finally conceiving two daughters, she had ''spent [her] whole life'' trying to get pregnant.

Speaking to The Australian Woman's Weekly magazine, she said: ''I had spent my whole life trying to get pregnant. [Keith and I] both were desperate to find that person [to have children with]. We'd also reached that place of going, 'Gosh, I wonder if it's ever going to happen.'''

The 'Big Little Lies' star married Keith 13 years ago, and she gave birth to their first daughter in 2008.

Meanwhile, Nicole recently opened up about her parenting techniques, insisting she won't be trying to get them ''into'' her profession.

She said: ''You can't really get kids into anything, I've realised. You can push them a bit, but motivation is a really hard thing. I mean, nobody motivated me to be an actor; if anything they tried to deter me.''

And the 'Aquaman' actress thinks it is important to have ''boundaries'' for her young children.

She added: ''They don't have a phone and I don't allow them to have an Instagram. I try to keep some sort of boundaries.''

Nicole - who is a Goodwill Ambassador for UN women - is also doing her best to educate her daughters about causes that she is passionate about, such as campaigns to end violence towards women.

She said: ''I was talking to Sunday about there being little girls in different parts of this world who don't own their bodies. A man owns their body. Her eyes were like 'What?' We're trying to educate about those things. But it's giving the information gently, and then guiding.''