Weak reflexes in newborns

Weak reflexes in newborns: Assessment of the nervous system

A newborn baby arrives with a full set of automatic, innate reflexes that are indicators of the health of its central nervous system. The pediatrician always checks these reflexes during the first examinations. Their symmetry and prominence allow assessment of whether the brain and neural pathways of the infant are fine. Weakening or absence of certain reflexes can be a warning sign.

Most important innate reflexes

• Sucking reflex: When the mouth is touched, the baby begins making sucking motions.
• Rooting (Kussmaul) reflex: When the cheek is stroked, the baby turns its head toward the stimulus.
• Grasp (Robinson) reflex: If a finger is placed in the baby's palm, it will tightly grasp it.
• Moro reflex: In response to a sudden sound or change in body position, the baby throws its arms out to the sides and then brings them together as if hugging itself.
• Support and stepping reflex: When the baby is held upright so its feet touch a surface, it "plants" its legs and can make "stepping" movements.

Read more about each of them in our article "Innate reflexes — health indicator".

Why can reflexes be weak?

Weakening or absence of reflexes can be associated with various conditions:

• Prematurity: In infants born before term, the nervous system is still immature, and reflexes may be weak.
• Birth trauma or hypoxia: Injury to the brain or spinal cord during delivery.
• Congenital disorders that affect the nervous system or muscles.
• Serious condition of the infant: For example, severe infection or metabolic disturbances.

Only a doctor should assess reflexes. If you notice that your baby is very sluggish (lethargy) or has weak muscle tone, this warrants an unscheduled consultation.