Nicole Kidman has said she is shocked when she thinks about how young she was when she married former husband Tom Cruise.

Having become a couple while working together on the film Days of Thunder, the A-listers tied the knot in 1990 when Kidman was 23 and Cruise was 28. They adopted daughter Isabella in 1992 and son Connor in 1995 before splitting in 2001.

Reflecting on her marriage to Cruise, Kidman told Red magazine: "I was so young when I got married. I look back now and I'm like, 'What?' You look at Taylor Swift, I mean, how old is she? She's 26. I had two kids by the time I was 27 and I'd been married for four years. But that's what I wanted."

At the Oscars in March 2000

Kidman married country singer Keith Urban in 2006 and they have two daughters, Faith and Sunday Rose.

They celebrated their tenth wedding anniversary in June, but Kidman admitted that it was "really up and down for the first three months".

"We've been through a lot for 10 years. And we're stronger than ever," she said. "I say that while touching wood, and no way in a boastful way. I just say it with wonder. Absolute wonder."

Nicole Kidman and Keith Urban at the Golden Globes in January 2011

"When you're older, you've been through things, you've made mistakes," she continued. "So you come into it [a second marriage] still giddy, but wanting it to last.

"We always consider the 'us'. We say, 'Is this going to be good for us?' It's the simplest phrase, but it works."

Kidman said that Urban describes her as "deeply maternal". "I like to take care of people. It brings me a lot of joy," she said.

For the Oscar winner, motherhood is "about the journey".

"There are going to be incredible peaks and valleys, whether you are an adopting mother or a birth mother," she added. "What a child needs is love.

"It's not necessarily great for a child to have an intensely emotional mother. And I don't want to be a helicopter parent so I'm trying to... balance the intensity of the love. It's really hard."