Wearables are all the rage, and now the newest member of your family can have one of his or her own. Consider it a Fitbit for your baby – except these devices don’t track steps, instead showcasing measures such as oxygen levels, heart rate, temperature and body position. You simply slip these products onto your newborn's foot, ankle or stomach, depending on the device, and monitor their vitals right on your phone.

One such product, Mimo, is available now for $199.99. Two other products, Owlet and Sproutling, are available for preorder for $250 and $299 respectively. But these products, which claim to help parents keep their babies safe, are more likely to prey on the fears of new parents, says David King, a clinical lecturer of pediatrics at the University of Sheffield in England.

“A lot of the marketing around these devices is about the fact that they allow you to monitor your new baby and keep them safe,” says King, author of a new commentary on these products, published Tuesday in the peer-reviewed medical journal BMJ. “I would ask the manufacturers exactly why a baby needs monitoring and how this would mean they are safe. Otherwise, it is merely taking advantage of new parents' fears and worries without offering any obvious benefit.”

Carlo Reyes​, a pediatrician and chief of staff​​ at Los Robles Hospital and Medical Center in Thousand Oaks, California, agrees with King’s commentary, adding that parents buy these devices under false pretenses. “There’s a false sense of security that these products can prevent something, when they likely won’t,” he says.

Devices like Owlet contain a sensor that monitors the child's vital signs and wirelessly transmits that data to an app on the parent's smartphone. In addition to showing current information, the app lets you track historical trends. However, ​simply monitoring your baby’s vital signs doesn’t give you any usable information, King says, and constantly checking the app​, ​which new parents are wont to do, will only cause unnecessary stress. “Young babies sometimes drop their oxygen levels and hold their breath, but only for a short time,” King says. “We don't fully understand why babies do this, but it doesn't indicate the child is more likely to suddenly stop breathing and die.”

Part of King’s criticism of wearables for babies stems from the fact that even though manufacturers display small disclaimers on their websites saying the devices are not intended to prevent sudden infant death syndrome, manufacturers admit fears over SIDS drive development, and many include the syndrome in their marketing materials. In one example King cites in his paper, Sproutling’s CEO tells Time he came up with the idea for the product because he worried about his baby suddenly dying and would constantly check to see if she was still breathing.

King also calls out the manufacturers of these products for skirting regulation by the Food and Drug Administration. As they stand now, the products are not sold as medical devices, despite the fact that consumers see them that way, solely because they lack an alarm to alert parents if there is a change in vital signs. Due to the lack of regulation, manufacturers are not required to demonstrate any kind of efficacy or accuracy, which Reyes says is problematic: "If you’re not making it a medical device, what’s it for? Since it’s not FDA-approved, we don’t know how accurate it is at recording baby’s vitals. These devices are catering to concerned parents, but I’m not sure what they're supposed to do beside show numbers that may or may not be correct.”

There are cases when doctors would prescribe either inpatient or at-home monitoring, Reyes says, but that would be done with FDA-approved devices. “In preterm infants and other high-risk situations, doctors might recommend something,” he says, “but it would be something rigorously tested and with an alarm.”

But just because it’s not sold as a medical device doesn’t mean it’s not useful or accurate, says Kurt Workman​, founder and CEO of Owlet Baby Care, who likened his product to in-home baby monitors. “The appeal of Owlet is that it’s a way for parents to feel much needed peace of mind, allowing them to sleep easier,” he says. “We’ve spent an extra year of testing and developing to make sure that product is reliable and accurate. We could have shipped something a year ago that may have given false peace of mind, but instead we’ve dedicated our product to quality and reliability.”

Workman also disputed King's idea that the product surreptitiously says it can prevent SIDS. “I have hundreds of comments from Owlet testers, and none of them focus on SIDS,” he says. “They just want to know if something is wrong. As parents, we’re tired of monitors that only serve a purpose when we’re awake. We want something that can let us rest easier.”