Extrusion Reflex: Why Do Babies Have It?


Extrusion Reflex


Extrusion reflex also referred to as tongue thrust reflex, is among many newborn reflexes.

A baby opens the mouth within this reflex and expands the tongue if their lips have been touched.

The extrusion reflex serves a function and is an indication of a baby’s normal development.

The reflex melts off as the infant grows old, and its persistence beyond infancy may signal an inherent orthodontic issue.

This article informs you about extrusion Biology in infants, the time of its disappearance, and signals that suggest extrusion reflex could be an issue.

Why Do Babies Have Extrusion Reflex?

The newborn reflexes are more spontaneous, involuntary activities that are part of an infant’s expected growth.

Several of those reflexes happen during a specific developmental period and diminish while the baby develops.

The existence of those reflexes helps ascertain whether the infant’s nervous system and behavioral systems will work all right.

The extrusion reflex is one of the infant’s reflexes.  It induces a baby to extend out their tongue, responding to their lips being touched.

It is essential to know that it does not interfere with the baby’s ability to latch onto a breast or bottle nipple but averts them from feeding on a cup or a spoon.

Besides the gag reflex, it allows the baby to expel any solid food if they are not ready for it. 

Hence, the extrusion reflex defends the baby from choking or aspiration due to solid foods and other foreign objects.  

When Does Extrusion Reflex Appear?

The extrusion reflex is already present at birth, suggesting that the infant acquires it at the time of pregnancy.

 It is not for sure known when the fetus develops this reflex. 

It may start developing between 32 and 36 weeks of gestation when other newborn reflexes, such as the sucking reflex, also develop.

When Does Extrusion Reflex Vanish?

The extrusion reflex vanishes between the four and six months of infants’ age. 

This is the age when infants are getting ready for solid food and can sit on their own. 

Seeing that baby is ready to transition to solid food, the extrusion reflex is becoming redundant.

Center for Disease Control and Prevention (CDC) and the American Academy of Pediatrics (AAP) claim that baby is ready to transition to solids once they display the following attributes.

  • Capability to sit in a high chair or feeding table without the support and with reasonable control of the head
  • Open up the mouth once the food is presented or a feeding instrument closes in.
  • Ingest 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 not sure if the infant still has their extrusion reflex, you may wish to test check its presence.   

How To Test If Infant’s Extrusion Reflex Remains?

Parents may check for extrusion reflex by offering an empty spoon to the infant. 

Should the baby thrust their tongue out and push the spoon, then they indeed still have the extrusion reflex active.

Should the infant accept the spoon, we can safely consider that the extrusion reflex goes away.

Infants older than six months rarely have tongue thrust, and parents can start offering them solids. 

However, individual babies may continue to have extrusion reflexes although being ready for solids. 

You may wish to see a healthcare provider in such cases. 

When is time To See A Doctor?

Consult a pediatrician if a baby has extrusion reflux past the age of six months. ‘

An infant with perpetual extrusion reflexes can as well show the specified signs.

  • Too swift, sluggish, or sloppy eating with perpetual dribbling of food
  • Incapable of closing the lips fully
  • The tongue protrudes out when the mouth is resting or when the infant is eating or talking.
  • Difficulty munching dense food
  • Speech issues in case of older infants

Constant tongue thrusting in babies could indicate an orofacial myofunctional disorder (OMD), leading to orthodontic issues, such as wrong aligned permanent teeth, in later life. 

It can as well affect the baby’s speech development.

A pediatrician or an orthodontic specialist will advocate the suitable treatment schedule to treat the underlying problem, such as orofacial muscular problems, and cure abnormally persisting extrusion reflexes.

Parents can help by observing therapy sessions and making the child practice in between sessions.

What Other Reflexes Do Infants Have?

These are other newborn reflexes that are found at birth or develop later after arrival.

Sucking reflex: When a bottle or breast nipple is set on the infant’s lips and then rolls the roof of the infant’s mouth, then they automatically start to suck.

The reflex generally wanes by four weeks old. It manifests approximately 32 weeks of maternity and develops at approximately 36 weeks.

Rooting reflex: When the corners of the infant’s lips, mouth, or lips have been touched, the infant turns at the path of touch and also opens their mouth.

The rooting reflex helps infants find the bottle or breast nipple and start feeding. The reflex will fade off by four weeks old. 

Moro or startle reflex: The infant will throw their head back, stretch their arms out and legs, then pull them back again. The reflex declines by two weeks old. 

Tonic neck reflex: It is likewise referred to as the fencing posture, and the reflex wanes by seven and five months. The infant can roll over just after this reflex disappears. 

Grasp reflex: It is likewise called palmar grasp reflex and reduces between five and five months old.

By touching or stroking your infant’s palm, they tend to grasp your finger or another object by closing fingers in a grasping fashion.

Voluntary grasp develops just following this reflex grasp vanishes. A twin reflex in the toes vanishes at 9 to 12 weeks old.

Stepping reflex: When the infant is held upright with their toes in contact with a surface, they start to move their legs at stepping actions, like climbing a flight of stairs. This reflex wanes by two weeks old.

Extrusion reflex is one of the essential newborn reflexes, and it prevents aspiration or choking in babies.

This reflex gradually fades when the baby is ready for solids, which is around age six months.

If the reflex lasts past six weeks, then speak to a physician for treatment and evaluation.


1. Development of Infant Feeding Skills; USDA
2. Guide to Breastfeeding; NHS UK
3. Newborn Reflexes; Stanford Children’s Health
4. When Can My Baby Start Eating Solid Foods?; Rady Children’s Hospital-San Diego
5. FAQ: Introducing Your Baby to Solid Foods; UCSF Benioff Children’s Hospital
6. When What, and How to Introduce Solid Foods; CDC
7. Starting Solid Foods; AAP
8. What is a Tongue Thrust?; Intermountain Healthcare
9. OrofacialMyofunctional Disorders (OMD); Cincinnati Children’s Hospital Medical Center