The presenter, who said she was leaving Radio 1 last week to concentrate on being a mum, told guests at the Tesco Mum of the Year Awards in London: "I'm craving a lot of carbs and had bad morning sickness. I'm not going to find out the sex. I'll be happy with either."
The star, who is ambassador for the awards this year, kept her bump hidden in a loose-fitting lace yellow and white frock at the ceremony in London as she mixed with other celebrities including Ola Jordon, Jennifer Metcalfe, Jo Joyner, Zoe Ball, Michelle Heaton and Lorraine Kelly.
Fearne , 33, said she feels extremely 'blessed and happy' about their impending arrival and that her son Rex, who she gave birth to in February 2013, will get to be a big brother.
In a statement on her website, the mum – who married the son of Rolling Stones guitarist Ronnie Wood last July – said: "Jesse and I are very happy to announce we are having another baby. I feel extremely blessed and happy that Rex will be a big brother, and we get to welcome another Wood into the world.
It has also been a time of big decisions and one I want to share with you now. After much time and careful thought I have decided to leave Radio 1 after ten amazing years.
"I have had the most incredible decade broadcasting on Radio 1, meeting wonderful people, helping break artists and watching live music from the world's best.
"However it is now time for a new chapter.
"I would like to thank Radio 1 for being such a great home and most of all to the listeners who have been on this journey with me. It's such a kick to know you heard a band on my show first, or that the songs I've played have helped you through the day, so thank you.
"I will leave with the best memories and many great friends.
"Here's to family and new adventures.
The presenter's best friend, Holly Willoughby, was one of the first to Tweet her congratulations, writing:
Congrats @Fearnecotton and Jess.... So much love to you and bumpino! Xxx
- Holly Willoughby (@hollywills) February 27, 2015
More on Parentdish: Fearne Cotton talks about shock of becoming a step mum
More:Pregnancy Week By Week
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