The 35-year-old presenter and West End actor Lee Mead named their daughter Betsy, according to the Sunday Mirror's celebrity and entertainment columnist Dean Piper.
The journalist wrote on his Twitter page: "Congratulations to Denise Van Outen and Lee Mead who just welcomed their first daughter Betsy Mead into the world!
"I'm so pleased for Denise and Lee - they're a great couple and this little bubba will really complete them. That's all - for now."
Van Outen announced in January that she and Mead were expecting a girl, adding that she was euphoric over the impending arrival.