Newborns do not experience true motion sickness, or kinetosis. Motion sickness is a neurological response triggered when the brain receives conflicting signals from the body’s sensory systems. This sensory mismatch, such as the inner ear sensing movement while the eyes see a stationary interior, triggers nausea and vomiting. Since a newborn’s sensory integration is not yet mature, this conflict cannot occur.
The Immature Vestibular System
Infants are immune to motion sickness due to the underdevelopment of the vestibular system, the body’s internal balance center located in the inner ear. This complex system, composed of the semicircular canals and otolith organs, senses motion, spatial orientation, and linear acceleration. Although the vestibular system begins developing in the womb, its ability to coordinate with other senses is limited during the first months of life.
Motion sickness requires a functional conflict between vestibular input, visual input, and proprioception (the sense of where the body is in space). A newborn’s visual system is still developing and cannot effectively track the external environment. Furthermore, because the baby is securely restrained and rear-facing, proprioceptive feedback is minimal. This lack of sophisticated sensory integration prevents the brain from receiving the contradictory data necessary to trigger the sickness response.
Identifying Causes of Car Distress
Although true motion sickness is not a factor, newborns can still exhibit distress during car travel, which parents often mistake for car sickness. Fussiness is usually related to general physical discomfort or digestive issues. Spit-up and vomiting are frequent occurrences due to a still-developing digestive tract and common gastroesophageal reflux.
The upright, restrained position in a car seat can exacerbate reflux symptoms, causing a rejection of milk that mimics car sickness. Other common sources of distress include thermal regulation, as the combination of the seat, blankets, and a warm vehicle can lead to overheating. Discomfort from being too hot or cold, hunger, or a wet diaper also causes crying and fussiness. Serious concerns also exist around positional asphyxia, where slumping causes the chin to press against the chest, restricting the airway.
Safe Travel Tips and Developmental Timelines
Parents can take several steps to minimize discomfort and ensure a safe car ride for their infant.
- Schedule car travel around the baby’s natural sleep windows, as a sleeping infant is generally more content.
- Avoid giving a large feed immediately before buckling the baby into the car seat to address digestive comfort.
- Maintain a comfortable temperature by dressing the baby lightly and removing coats or heavy blankets after securing the harness.
- Ensure the car seat is installed correctly and the harness is snug to prevent slumping, which is a safety concern for positional asphyxia.
The timeline for true motion sickness begins to shift as sensory systems mature, typically becoming a possibility around two years of age. From this age onward, the coordination between the inner ear and the eyes is developed enough for the sensory conflict to occur. Parents may then notice signs of nausea, paleness, or unusual quietness during car journeys.