Introduction to Infant Reflexes

Infant reflexes are involuntary movements critical for a baby’s survival and development. Therefore, nurses often assess these reflexes during physical exams to ensure proper neurological function.

Assessing these reflexes can provide valuable information about an infant’s neurological development and any potential issues requiring further evaluation or intervention.

Nurses need to assess infant reflexes and muscle tone in physical exams to ensure that the baby’s nervous system and motor development are progressing normally. The presence or absence of certain reflexes and muscle tone can indicate underlying neurological or developmental issues, such as cerebral palsy, spinal cord injury, or developmental delay. 

Early detection and intervention of these issues can lead to better outcomes for the infant, including improved motor skills and quality of life.

The 7 Infant Reflexes

The seven most common reflexes included in infant physical assessments include:

1. Babinski Reflex

This reflex is elicited by stroking the sole of the foot from heel to toe. A normal response is for the toes to fan out and the big toe to extend upward. This reflex typically disappears around 24 months of age.

2. Rooting Reflex

This reflex is elicited by touching the infant’s cheek, which causes the infant to turn their head and open their mouth in the direction of the stimulus. This reflex helps with breastfeeding and disappears around four months of age.

3. Tonic Neck Reflex

Also known as the “fencing reflex,” this reflex is elicited by turning the infant’s head to one side while lying on their back. The infant’s arm and leg on the side they are facing will straighten, while the opposite arm and leg will bend. This reflex disappears around five to seven months of age.

4. Moro Reflex

This reflex is elicited by making a sudden loud noise or by quickly lowering the infant’s head backward. The infant will typically extend their arms and legs, then bring them back toward their body in a hugging motion. This reflex disappears around two months of age.

5. Stepping Reflex

This reflex is elicited by holding the infant upright with their feet touching a flat surface. The infant will make stepping movements as if trying to walk. This reflex disappears around two months of age.

6. Palmar Grasp Reflex

This reflex is elicited by placing a finger in the infant’s palm. The infant will automatically grasp the finger tightly. This reflex disappears around five to six months of age.

7. Plantar Grasp Reflex

This reflex is elicited by pressing on the ball of the infant’s foot. The infant will curl their toes in response. This reflex disappears around nine to twelve months of age.

Non-Normal Infant Reflexes

The following could indicate the infant needs further medical evaluation:

• Absent reflexes
• Hyperactive reflexes
• Asymmetric reflexes
• Persistent primitive reflexes beyond their typical time frame
• Clonus (involuntary muscle contractions in response to muscle stretching)
• Extensor plantar reflex (Babinski sign) beyond 12-18 months of age.

Sources

https://www.chop.edu/conditions-diseases/newborn-reflexes