You’re hooked on your Fitbit, Apple Watch or Jawbone UP because of all the cool data it gives you about your health. Maybe you’re even one of the early adopters of T-shirts with monitors built right into the fabric (underwear coming soon!). It makes sense, then, that if you’re a parent, you may be tempted to strap some wearable tech devices on your baby, too.

If you are, read before you leap.

Related: Is Co-Sleeping With Your Baby Safe?

Baby wearables track almost anything and everything going on in the crib, from sleep patterns to breathing rates. (How did parents ever survive without them?) There’s the Mimo, a high-tech onesie with a built-in monitor that tracks breathing patterns, body position and skin temperature. There’s Sproutling, an ankle band that tracks similar data and heart rate and can even predict when your baby will wake up from her nap. Owlet is a bootie or “smart sock” that tracks breathing and oxygen levels, with a smartphone link and a base station featuring an alarm that sounds if something is amiss. Another device is MonBaby, a baby monitor in the form a button that snaps onto clothing and records breathing and position, sending data to a smartphone app and alerting you if your baby stops breathing or rolls onto her stomach.

Given that the wearable tech industry is growing even faster than babies do, devices like these are bound to be hot. And that’s literally part of the problem, or could be: Nobody really knows how hot these devices can get, and baby skin is incredibly sensitive.

Unlike with adult wearables, a few extra degrees concentrated in one spot could pose a problem for a baby. A lot of the safety issues UL has been testing get amplified when it’s a baby because they do not have the ability to roll over if something is getting hot. It may only be a few degrees, but as time passes a red spot can develop on the baby.

Another concern is chemical reactions between a wearable’s synthetic materials and water — either baby sweat or urine — trapped near the skin. A baby ends up with diaper rash from urine in its diaper. Drengenberg notes. If you’re going to put a sensor on your baby before you put the baby to sleep, it is important to remember the sensor’s going to be on that baby for hours.

Babies, meanwhile, are a helpless bunch. They can’t tell you if the device is keeping them from sleeping well or irritating their skin.

Related: The Sleep-Safe Baby Guide

UL points to a few other areas of potential concern. Babies are prone to perspiring, especially when they have a fever or teething pain or are just too heavily swaddled. And sweat conducts electricity — which means there’s a theoretical risk for electric shocks.

Then there’s the question of long-term exposure to radio frequency energy near a developing baby’s brain. It is important to keep in mind, a baby’s brain is still forming, researchers still haven’t come to a conclusion on the effect of radio frequencies on the human brain.

Research will eventually provide more answers on the safety of wearable baby tech. It could turn out that the advantages of constant monitoring, whatever they might be, are outweighed by the risks. For now, UL warns tech-enthusiast parents that because babies are a special “at-risk” group, it pays to be cautious.

Related: Solving the Sleepless Baby Nightmare

Greg writes about personal finance, business and technology. His work has appeared in Businessweek, Newsweek, Forbes, Bankrate and a variety of trade ​publications.