Victoria Fritz, who presents the business news on BBC Breakfast, found her waters breaking on Tuesday after leaving the studio.
When fellow presenter Sally Nugent discovered that Fritz’s husband was stuck on the motorway, she said she would stay with her at the hospital until he arrived.
But because of heavy traffic on the M6, Fritz’s husband did not get there on time, and Nugent ended up being birthing partner for the arrival of a baby boy.
A BBC spokeswoman said: “When Sally heard that she’d gone into labour she offered to be there until Victoria’s husband got there. But her husband never arrived so she found herself at the birth.”
The baby had been due to arrive in early December.
Fritz tweeted: “My heartfelt thanks to Sally Nugent and St Mary’s doctors and midwives who helped me deliver my little boy yesterday. A @BBCBreakfast team effort!”
Nugent wrote: “You won’t believe what happened after work yesterday. Huge congrats to our very clever @VFritzNews.”
BBC Breakfast presenter Dan Walker wrote: “Thank you for all your suggestions for baby names for @VFritzNews but I think Baby McBabyFace might not make the grade @BBCBreakfast.”
BBC Breakfast tweeted: “Congratulations @VFritzNews! Victoria should have been our biz presenter today - but instead has some more exciting news to deliver!”