23-year-old Feng Yu -- who was near the end of her pregnancy -- felt contractions 50 minutes into her two-hour flight from China's Sichuan Province to Wuhan on Tuesday.
Though women more than seven months pregnant are advised not to fly, Yu is thin and wore heavy clothes, so no one suspected how close she was, airport officials told Shanghai Daily.
Luckily, four crew members were trained to handle on-flight birth and safely delivered the baby.
"I was frightened when the baby's head came out but the body was still stuck. ... I asked myself to calm down and firmly held the woman's hand and tried hard to recall what I had learned from emergency training," said Zuo Lei, one of the attendants.
When the baby -- who was named Angel -- was born, passengers cheered and clapped, another attendant told the newspaper.
The flight landed seven minutes later and medical workers took Yu to a nearby hospital. A doctor told Shanghai Daily that both mom and baby are doing well.
Yu isn't the first mom to give birth at 40,000 feet: In September, Aida Alamillo delivered above water heading from Manila to San Francisco, meaning her baby's nationality was up in the air -- pun intended. And, just a week before that, a French woman delivered on her way to Paris.
Click through this list of 10 more unexpected birthplaces. Then, let us know if you had a shocking birth experience in the comments.