No, it is not safe for a baby to sleep with a pacifier holder. Pacifier holders are designed to attach the pacifier to your baby’s clothing to prevent it from falling or getting lost, but they should be removed before your baby goes to sleep. The American Academy of Pediatrics (AAP) recommends that parents put babies to sleep on their backs, without any objects or loose bedding in the crib. This includes pacifier holders, which could pose a suffocation hazard if they become wrapped around your baby’s neck or interfere with breathing. If your baby relies on a pacifier to fall asleep, it’s best to offer it to them when you’re putting them down for sleep, but remove it once they’re asleep. If your baby wakes up and wants the pacifier again, you can offer it to them, but make sure to remove it once they sleep again.