Nicole Kidman went through "pain, loss and disappointment"
The 43-year-old actress - who welcomed Faith Margaret, her second child with country music singer Keith Urban, into the world on December 28 via a gestational carrier - admitted she suffered agonising times when trying to conceive.
She explained: "Anyone that`s been in the place of wanting another child or wanting a child knows the disappointment, the pain and the loss that you go through trying and struggling with fertility.
"Fertility is such a big thing, and it`s not something I`ve ever run away from talking about."
The `Rabbit Hole` star - who also has a two-year-old daughter Sunday Rose with Keith, as well as adoptive children Isabella, 18, and Connor, 15, with ex-husband Tom Cruise - explained she and her country singer spouse were in a position where while they were "desperate" for another child, but she couldn`t get pregnant.
Nicole added to Australian TV show `60 Minutes`: "We were in a place of desperately wanting another child. The opportunity arose for us, and I couldn`t get pregnant.
"Children are children - you`ll die for your children. And when you feel that as parent - that`s the unconditional love."