As babies grow older and their central nervous system develops gradually, the startle reflex generally disappears slowly at 3-5 months of age and disappears completely at about 6 months. The startle reflex is a whole body movement, also known as the hug reflex, which is a temporary reflex in the newborn period and can be observed more clearly when the baby is lying down. When the baby’s startle reflex appears, the arms will first straighten and spread outward, then bend and fold inward, accompanied by finger separation, back stretching or bending, head tilting back, legs tensing, arms in a hugging state, and sometimes crying out, even during sleep. Usually the startle reflex disappears 3-5 months after birth, but if it persists beyond that time, it is recommended to consult a pediatric neurologist promptly. When a baby has a startle reflex, parents can use a soft voice to comfort the baby, and at the same time, touch, such as stroking the baby’s head or patting the back, to help the baby feel safe and soothed.