Babies Baby Development What Every Parent Should Know About Baby Tremors and Shakes Baby shaking and tremors are to be expected, but they could signal a bigger issue. Here's what parents need to know. By Vincent Iannelli, MD Published on February 26, 2024 Medically reviewed by Lyndsey Garbi, MD In This Article View All In This Article Fine Motor Skills Development Immature Nervous System The Startle (Moro) Reflex Caffeine in Breast Milk Sleeping or Waking Up Diaper Changes Hunger Other Causes of Baby Shakes and Tremors Signs of Seizures in Newborns Key Takeaways About Baby Shakes and Tremors Trending Videos Close this video player Parents / Julie Bang As a new parent, it's easy to get worried when you see your newborn's odd, shaky movements, from quivering chins to trembling hands and jitters to jerky arm and leg gestures. In most cases, these extra movements are completely normal and harmless, and it's likely that your baby will outgrow them. Babies can, however, have seizures, so it's important to understand the difference between normal baby shakes and a more serious issue. Here we look at some common causes of baby shaking, and how to know when to be concerned. Fine Motor Skills Development Different parts of the body tend to twitch at different developmental stages, and this can expected as a natural part of fine motor skills development. For example, during the neonatal period (the first 28 days of life), shaking of the head and extremities prepares babies for holding up their heads. In older babies, twitching of the wrists and fingers may be part of the development of fine motor skills. Immature Nervous System In newborns, the pathways that carry the signals from the brain to the parts of the body aren’t yet fully developed, causing jerky and twitchy movements. As the baby's nervous system matures, by around 1 to 2 months old, these movements will become more fluid. The Startle (Moro) Reflex 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. Swaddling or using a sleep sack can help curb the reflex during naps. Caffeine in Breast Milk If you’re breastfeeding and you drink a lot of caffeinated beverages such as coffee or soda, it may cause the baby to twitch or jitter. While a little caffeine (up to 300mg, or about two to three cups of coffee) isn't a problem, large amounts can pass to your baby and build up in their body. Sleeping or Waking Up Shaky and twitchy movements are also likely to occur when a baby is falling asleep or waking up. What you are seeing is likely a benign condition known as sleep myoclonus, also known as nocturnal myoclonus, and it usually occurs at the moment of dropping off to sleep. External stimuli such as noise, movement, or light can also cause these movements. Sleep myoclonus usually resolves within a year and there are no inherent consequences or reasons for concern. Diaper Changes If shaking movements occur every time you change their diaper, it might simply be your baby's way of telling you that they don't like having their diaper changed. Hunger Moving their arms and legs all around can be one of the signs that your baby is hungry. Crying, which can also create shaking, trembling, or stiffening of the body, is also a late sign of hunger. But frequent, prolonged, and consistent crying, along with shaking, may be a cause for concern and should be addressed with a doctor. Other Causes of Baby Shakes and Tremors There are other reasons for baby tremors, including being cold, as well as having low blood sugar. Other signs of low blood sugar, also called hypoglycemia, can include a blue tint to skin or lips, lethargy, and/or lack of interest in feeding. If you suspect your baby might be suffering from low blood sugar, be sure to reach out to their pediatrician or healthcare provider. A Parent's Guide to Colic in Babies Signs of Seizures in Newborns Seizures in newborns are different from seizures that occur in older children and adults. In general, the following signs may indicate your infant is experiencing a seizure: Movements and behaviors that are not typical of children of the same ageRepeated episodes that are identical in both features and durationEpisodes that are not brought on by changes in posture or activityNoticeable change in the baby's facial expression, breathing, and heart rateMovements that are rhythmic and may occur on only one side of the body, or are symmetric (for example, both arms do the same thing at the same time)Shaking or jerking that cannot be stopped (if an infant's arm is jerking and you can stop it by gently holding their arm, then it probably isn't a seizure; with a seizure, you would expect the jerking to continue as you held their arm) Keep in mind that when a baby first begins having seizures, they may be otherwise fine, but over time, you would expect some other symptoms or problems with their development if they were having frequent seizures or spasms. Key Takeaways About Baby Shakes and Tremors The first time you notice your baby shaking while they're crying or twitching in their sleep can be nerve-wracking. Try to remember that these movements are very common among infants as babies figure out their bodies and environment. Of course, if you suspect seizures or are concerned about shaky movements, don't hesitate to call your pediatrician to double check. It is often helpful to record the suspicious activity if you can and bring the video to your pediatrician to view. The doctor can put your fears to rest and/or recommend the proper treatment if it's indeed more than normal baby movements. Everything You've Wanted to Know About Taking Care of a Newborn Baby Was this page helpful? Thanks for your feedback! Tell us why! Other Submit Sources Parents uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. 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