According to the study's authors, having your infant in the upright position that's created in a car seat for an extended period of time could increase the risk of suffocation—and they urge parents to avoid keeping their infants in car seats for more than 30 minutes at a time.
The researchers used a simulator to mimic the position a child assumes in a rear-facing car seat. They tested 19 healthy newborns who were born at term and 21 newborns who were born preterm. The study's authors reproduced the vibration an infant might face when riding in a car driving at 30 miles per hour.
The babies studied had a median age of 13 days and weighed about 2.5 kg. Researchers found that when infants were placed at 40-degree angles and experienced the vibration caused by a moving car, their respiratory and heart rates increased and oxygen saturation decreased.
The study's findings are worth taking into account—especially for parents of premature infants or babies with underlying health issues, says David Mathison, M.D., a pediatrician and pediatric emergency physician.
"In very young infants who have underlying cardio-respiratory problems, gastro-esophageal reflux, or who were born very prematurely, the car seat position may not be ideal—but you have to balance this with a mechanism to keep your child safe in a car, which is a potentially dangerous mode of transport that has its own risks. For these infants, a conversation with a physician is advised before planning a long car trip," Dr. Mathison says.
If you do need to travel long distances, take frequent breaks to give your baby time out of the car seat—or consider having family travel to you this holiday season.
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