Infants have highest risk of death on airline flights, a new research by the University Hospitals Rainbow Babies & Children's Hospital (UH Rainbow) shows.

After examining pediatric medical emergencies on flights globally between January 2010 and June 2013, researchers found that 90 percent of reported deaths were of children aged below 2.

The study was done in collaboration with MedAire to find about in-flight pediatric fatality rates worldwide aboard commercial airline flights. Nearly 7,000 medical emergencies involving children (newborn to age 18) were assessed over a three-year period.

Most reported fatalities were of previously healthy children aged below age of 2 and in children with a pre-existing medical condition.

"The pattern we identified in our analysis is intriguing and could indicate lap infants are at greater risk of death related to in-flight environmental factors such as sleeping arrangements," said Alexandre Rotta, MD, FCCM, Chief, Division of Pediatric Critical Care Medicine at UH Rainbow and the studies' principal investigator, in a press release.

Researchers found that 10 fatalities were reported among the 7,573 reported emergencies and six of them had no medical history. Four passengers had pre-flight medical conditions, including two children traveling to get advanced medical care.

According to Dr Rotta, the infants might have been at greater risk of exposure to a hypoxic cabin environment, or by sharing a seat with an adult and co-sleeping during a long flight.

The researchers stated that most of the pediatric in-flight emergencies were associated with infections, neurological conditions, and respiratory issues such as asthma but researchers say there could be also an unknown factor. These conditions hardly require alteration of flight route and do not pose significant risk to life.

Due to the rare occurrence of in-flight pediatric deaths the research team used a broad dataset.

"I hope our findings lead to further research on this important subject," said Dr Rotta. "It is my belief the pattern we discovered should promote the development of preventative strategies and travel policies to protect the health of all pediatric airplane passengers, especially infants."

The study was published in the Pediatric Critical Care Medicine Journal.