Ada Guan boarded her international flight from Calgary, Canada to Tokyo without a care, and she didn't realize she'd leave the plane a new mother.
The Canadian woman reportedly didn't even know she was pregnant.
Air Canada announced on Sunday the 23-year-old gave birth to a healthy baby girl, Chloe, mid-flight.
According to CBC News, Guan did not realize the stomach pains she felt and the weight she gained were the results of being 37 weeks pregnant -- just one week past the airline's flying limit for pregnant moms.
Pre-flight, Guan reportedly took a pregnancy test and received a negative result. She even saw a doctor who apparently didn't notice the pregnancy, either.
Global News reports Guan told her boyfriend of a year, Wesley Branch, she wasn't feeling well while the two were on the plane.
The flight's crew moved her up to business class, and a few doctors administered an IV and gave her Tylenol, according to Global News.
Everything changed, however, when Guan felt something drop out of her.
New grandmother Sandra Branch told the Calgary Sun,
She told Wesley 'something fell out of me' and all of a sudden there was a baby... It turned out to be a beautiful baby girl.
Guan and Branch's new daughter is reportedly a Canadian citizen, but she may be eligible for dual American citizenship if she was born over Hawaii.