It’s easy for new parents to get worried when they see a newborn’s strange trembling movements, from trembling chins to trembling hands and tremors to jerky hand and leg gestures. In most cases, these extra movements are perfectly normal and harmless, and in most cases your child will outgrow them.

However, babies can have seizures, so it’s important to understand the difference between a normal baby’s trembling and a more serious problem. Here, we’ll look at some common causes of baby’s shaking and how to know when to worry. Different parts of the body tend to twitch at different stages of development. For example, during the neonatal period (the first 28 days of life), twitching of the head and limbs prepares infants to hold their head, while twitching of the wrists and fingers in older children may be part of fine motor development.

In newborns, the pathways that carry signals from the brain to parts of the body are not yet fully developed, which causes jerky and jerky movements. As the child’s nervous system matures, these movements become smoother. If a baby is suddenly surprised by a loud noise or other environmental stimulus, you might notice an involuntary movement in which the baby extends their arms, legs, and fingers and arches their back for a few seconds. This is called the Moro reflex , or startle reflex, and is common up until the ages of 3 to 6 months.