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, in most cases, your baby will outgrow them. Twitching of the head and extremities prepare babies for holding up their heads while twitching of the wrists and fingers in older babies may be part of the development of fine motor skills. 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 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.