Nicole Richie will marry fiance Joel Madden after she gives birth.

The Good Charlotte frontman says the couple will definitely tie the knot, but only after five-month pregnant Nicole has delivered their first child.

He told US radio DJ Ryan Seacrest on Tuesday: "Obviously marriage is in our future. I don't know when or how, but right now our priority is our family and the baby.

"That's all we've been thinking about. We are in love and we are really happy."

Joel, 28, also revealed the couple haven't found out the sex of their child and are currently referring to the baby as "it".

He said: "We are waiting to find out if it is a boy or a girl. We don't even know. So right now it's an 'it', which sounds wrong. We call it the baby.

When we talk to it, it's 'you'.

"I'm excited. It's the best thing that has ever happened to us. It's awesome.

"The baby has started kicking and I already went to Target and got a stroller and a playpen for the nursery."

Joel and Nicole, 25, have been together since early this year, and announced in July they were expecting their first child.