An apnea monitor is a machine used to detect periods when a baby's breathing stops for a short time. It is often used in the hospital and may also be used after the baby goes home.
Wires called leads are attached by adhesive patches to the baby's chest. The leads are connected to a monitor that shows whether the baby breathes more or less than a specific number of times per minute. If the baby's breathing changes a lot, an alarm goes off to warn the parents or hospital staff.