The bovine mum - named Brianna - jumped from 8ft above the ground onto a busy road, before being taken to a sanctuary.
But animal rescuers were shocked to discover the plucky creature had not only saved herself from the slaughterhouse - but her unborn calf.
-> Pulled over BMW driver avoids arrest for having flashing blue lightsThe mother gave birth to female Winter just two days after arriving at the rescue centre, where the pair are enjoying their newfound freedom together.
Mike Stura, founder of Skylands Animal Santuary in New Jersey in the USA, said: "I got a call from a friend of mine who's a police officer.
"He said there was a cow running down a big highway out here so I hopped into action.
"I got the rescue truck and headed out. When I got there the police had corralled her off the highway and on to a small road where they got a strap round her neck."
The 52-year-old added: "She fell out of the transport truck from at least 8ft off the ground while the truck was moving.
"A witness said she kicked the door out and jumped out on the the highway.
"At first, the truck driver didn't even realise."
After securing Brianna in his vehicle, he took her back to Skylands Animal Santuary in Wantage, New Jersey on December 27.
Mike, who was run the sanctuary for four years, said: "I had a vet come and he looked her over and that's when I found out she was pregnant.
"The vet said, 'There's a very big calf in there and she's going to have it in the next week or so'."
But Brianna gave birth just two days later, with Mike there to help bring newborn Winter into the world.
Mike added: "They're both happy and healthy, although Brianna suffered some abrasions during her escape."
The animal-lover said he wasn't sure if Brianna's bid for freedom was down to her being pregnant.
But he added: "Any way you look at it, all these animals want to live.
"Without question, I could tell you she was scared to death of being in that truck. It's not good; they just want out.
"This story resonated with people but many don't realise how many millions go unseen with this sort of stuff going on every single day."