The tongue thrust reflex in kids, also known as the extrusion reflex, may interfere with speech development and cause orthodontic problems related to teeth alignment. This reflex occurs when an infant opens their mouth and extends their tongue when the lips touch (1). It is a newborn reflex that is a sign of normal development. The extrusion reflex prevents babies from choking from foreign objects and foods. It disappears as the baby grows, usually by around four to six months. However, you may seek medical care if the reflex stays much beyond infancy. Read on to know about the tongue thrust reflex in kids and signs of concerns.

Why Do Babies Have Extrusion Reflex?

The newborn reflexes are spontaneous, involuntary actions that are a part of a baby’s normal development. Some of these reflexes occur during a specific developmental stage and then diminish as the baby grows. The presence of these reflexes helps determine if the baby’s nervous system and musculoskeletal systems are working fine. The extrusion reflex is one of the newborn reflexes. It causes a baby to extend out their tongue in response to their lips being touched. It does not interfere with the baby’s ability to latch onto a breast or bottle nipple but prevents them from feeding from a cup or a spoon. Along with the gag reflex, it lets the baby expel any solid food if they are not ready for it (2). Thus, the extrusion reflex protects the baby from choking or aspiration due to solid foods and other foreign objects.  

When Does Extrusion Reflex Develop?

The extrusion reflex is present at birth, indicating that the baby develops it during fetal life. It is not precisely known when the fetus develops this reflex. It may develop between 32 and 36 weeks of gestation when other newborn reflexes, such as the sucking reflex, also develop (3) .

When Does Extrusion Reflex Disappear?

The extrusion reflex disappears between the ages of four and six months (4). It is the age range when babies are ready for solids and can sit without support (5). Since the baby is ready to transition to solid food, the extrusion reflex is no longer needed. There are other signs that accompany the fading extrusion reflex and indicate the baby’s readiness for solids. According to the Centers for Disease Control and Prevention (CDC) and the American Academy of Pediatrics (AAP), an infant is ready to transition to solids when they display the following attributes (6) (7).

Ability to sit in a high chair or feeding table without support and with good head control Opens mouth when the food is offered, or a spoon approaches them Swallows food and does not push it out of the mouth Ability to transfer the food from the front to the back of the tongue Doubles their birth weight

If you are unsure if the baby still has their extrusion reflex, you may test to check its presence.   

How To Test If Baby’s Extrusion Reflex Persists?

Parents can check for extrusion reflex by offering a clean spoon to the baby. If the baby thrusts their tongue and pushes the spoon, then they still have the extrusion reflex. If the baby accepts the spoon, the extrusion reflex is gone. Babies older than six months seldom have tongue thrust, and parents can begin offering them solids. However, some babies may continue to have extrusion reflex despite being ready for solids. You may have to see a healthcare provider in such cases. 

When To See A Doctor?

Consult a pediatrician if your baby has extrusion reflux beyond the age of six months. A baby with persistent extrusion reflex may also display the following signs (8).

Too fast, too slow, or messy eating with constant dribbling of food Unable to close the lips completely Tongue sticks out when the mouth is at rest or when the baby eats or talks Problem chewing solid food Speech problems in case of older babies

Persistent tongue thrusting in babies could indicate an orofacial myofunctional disorder (OMD), which may lead to orthodontic problems, such as misaligned permanent teeth, later in life (9). It may also affect the baby’s speech development. A pediatrician or an orthodontic specialist will suggest the appropriate treatment plan to treat the underlying problem, such as orofacial muscular problems, and cure abnormally persisting extrusion reflex. Parents can help by observing therapy sessions and making the child practice in between sessions.

What Other Reflexes Do Babies Have?

The following are other newborn reflexes that are present at birth or develop later after birth (1) (3).

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