Parents who rely on popular commercial baby heart rate and oxygen monitors to warn against Sudden Infant Death Syndrome (SIDS) might want to reconsider, according to a study out of the Children’s Hospital of Philadelphia Research Institute released on Thursday.
The study, published in The Journal of the American Medical Association, tested the two monitors on the market that pair with smartphones: the Owlet Smart Sock 2 ($299.99) and the Baby Vida (seemingly off the market now). According to researcher and pediatrician Dr. Christopher P. Bonafide, who used the monitors on 30 slightly ill babies under the age of 6 months at the hospital, results were “surprising.”
“My biggest surprise is how differently the two monitors performed,” he told PEOPLE. Both use pulse oximetry technology — designed to monitor the levels of oxygen in one’s blood — and while the Owlet overall performed “very well,” it had inconsistencies, sometimes displaying a number that was not consistent with low oxygen levels, and on some occasions, indicating the baby was fine when pulse oximetry numbers said otherwise, based on a control, hospital-grade monitor.
“Somewhat shocking was that the Baby Vida had much more serious problems,” Dr. Bonafide explained. “The Baby Vida never successfully detected low oxygen levels, regardless of how low the baby’s oxygen levels were, to a point where they might be blue in the face. That’s a pretty serious problem that would potentially lead a parent of a baby who was very sick to think that their baby was okay.”
Additionally, “many times the Baby Vida had false readings suggesting the baby’s heart rate was dangerously low when it was actually completely normal,” Dr. Bonafide continued. “In that scenario, a parent might call the pediatrician, who’d recommend an trip to the emergency room — all unnecessarily.”
Dr. Bonafide decided to study these monitors after first coming upon them five years ago, when an infant was admitted to his hospital after a monitor the parents were using went off and doctors couldn’t find any obvious issues (it turns out, the child was fine).
The American Academy of Pediatrics already cautions against such monitors, claiming they are not shown to have any role in preventing SIDS or related issues — and they haven’t been approved by the Food & Drug Administration, either.
In a statement to PEOPLE, Owlet co-founder and CEO Kurt Workman noted, “Owlet sensor accuracy has been validated in studies performed by independent laboratories and when compared to arterial blood gas measurements the sensor performed well within industry standards for pulse oximetry. The accuracy and performance of the Owlet Smart Sock is something we take very seriously.” Results of the company’s own accuracy study are available here.
An independent pediatrician, Dr. Larry Constenstein, also questioned the methodology of the study via Owlet’s statement, pointing to the fact that “this study compares a consumer product for use in healthy babies with a hospital-based product being used in ill infants.”
Regardless, Dr. Bonafide said he wouldn’t recommend a monitor to friends or family with healthy babies — putting an infant to sleep on his or her back, alone on a hard surface is the recommended way to prevent SIDS — though “doesn’t fault” parents who do use them. (For babies who have serious illnesses that do require such monitoring, there are hospital-grade devices that are prescribed by pediatricians.)
“For parents who do chose to use them, they should feel comfortable talking about the monitor usage with their doctors,” Dr. Bonafide said, “and hopefully collaborate on a plan together for how the parents are going to respond when the alarms do go off in the middle of the night.”
PEOPLE could not find a contact for Baby Vida.