Sunday Brunch host Lovejoy, 45, tweeted the news this morning, writing: "Tamsin Greenway has put in the best performance of her life. Our baby girl Jamie Jeane Lovejoy arrived this morning. They're both well."
Jamie Jeane is the couple's first child together. Lovejoy has twin girls, Grace and Rose, from a former marriage.
Greenway, 30, is an English netball player and coach.
Lovejoy's Sunday Brunch co-star and close friend Simon Rimmer congratulated the new parents this morning, saying: "Big love to Tim Lovejoy and Tamsin Greenway on the birth of baby Jamie Jeane this morning. Uncle Simon is proud!"
It was revealed earlier this month that Lovejoy had landed a new Saturday magazine show on BT Sport.
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