Medically reviewed by Jonathan B. Jassey, DO Key Takeaways The Moro reflex is a startle response in babies that makes their arms extend and retract. Newborns grow out of the Moro reflex within the ...

Your baby's newborn reflexes – called developmental reflexes or primitive reflexes – are survival instincts triggered by their central nervous system. A reflex can be a spontaneous movement, but it's ...