Abstract

The Moro reflex is one of the most recognizable primitive reflexes in early neonatal life and provides important information about the functional status of the central and peripheral nervous systems. It is routinely assessed in newborns and reflects brainstem activity, motor pathway integrity, and developmental maturity. This review summarizes the physiological basis, method of elicitation, normal and abnormal patterns, and differences between preterm and term infants. Literature from standard neonatal references and indexed medical databases was reviewed. The reflex consists of a two‑phase sequence initial abduction and extension of the upper limbs followed by adduction and flexion mediated mainly through brainstem circuits. Abnormalities such as absence, asymmetry, or sluggishness may indicate neurological dysfunction, peripheral nerve injury, or systemic illness. The reflex appears during late gestation, is well developed at term, and typically disappears by 4–6 months of age. Accurate assessment of the Moro reflex aids in early identification of neurological abnormalities and guides further evaluation.

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