The former Radio 1 DJ and husband Jesse Wood welcomed their second child, a daughter, on Wednesday morning (9 September).
Fearne announced the happy news via Twitter, saying: "Jesse and I are over the moon and buzzing with love, as our baby daughter Honey Krissy Wood came into the world this morning."
The couple are also parents to son Rex, two.
Their choice of 'Krissy' as a middle name is a nod to Jesse's late mum, Krissy Findlay, who passed away in 2005.
In February, Fearne told fans: "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."
She and Jesse (who surprised fans by tying the knot in secret last July) weren't the only ones looking forward to meeting the Wood household's new arrival. Last month, Fearne revealed Rex has been talking to her baby bump
"Rex shouts HELLO through my belly button to the baby," she revealed.
While on maternity leave, Fearne has been working on her own recipe book called Cook Happy, Cook Healthy, due for release next year.
Over the summer, she insisted she would return to work once her second child was born, correcting reports that she was planning to be a stay-at-home mum with son Rex and the new arrival.
Fearne tweeted: "For many who are reporting I'm not returning to work after the baby. Absolute rubbish. I'm so excited about getting back to work at some point.
The star left her Radio 1 show in May after ten years on air in order to focus on other projects. She's still a panellist on Celebrity Juice and has a successful fashion and homeware line. She's also voicing a Voice Trumpet in the revamped version of The Teletubbies.
Relive Fearne's old maternity fashion
Copyright: Rex Features