Jessica Simpson ''freaked out'' after suffering false labour.

The 31-year-old fashion designer - whose first child with fiancé Eric Johnson is due next month - admits she worried she was going to give birth there and then.

She said: ''I had contractions last night and I freaked out a little bit. You know those Braxton Hicks things.

''It's like these contractions that pregnant woman have towards the end. It prepares your body for delivery. I'm prepared. It's scary. It's like, 'Oh God, this can happen right now'.''

The 'Fashion Star' mentor and Eric, 32, have already chosen a name for their daughter, although they have decided to keep it a secret for now.

Appearing on The Ellen Degeneres Show, Jessica said: ''We're not really saying it [publicly] until the baby is here. We've been calling her by name. She reacts to it.

''I could be one of those psycho moms that just thinks one little kick is her really listing to me. She's really like, 'Shut up!'''

Meanwhile, she admits pregnancy has given her an insatiable appetite for sex.

She told Ryan Seacrest's radio show: ''I am definitely 'feeling intimate'. I'm kind of unstoppable right now. The Big O is, like, the biggest O ever!''