Here's How Your Baby Knows How To Breathe After Birth

For nine long months, your baby has lived inside your body, surrounded by warmth and darkness and the comforting thump of your heartbeat. After labor and delivery though, your newborn will transition to a whole new world where they must eat on their own, sense surroundings on their own, and take their first breath on their own, too. But like many other parents, you might be wondering — how does my baby know how to breathe after birth? You may be surprised to find out that the medical community is still searching for a definitive answer.

As your baby develops in your uterus, it receives oxygen through your placenta because its developing lungs are filled with amniotic fluid. But following birth, your baby's central nervous system will react to the extreme change in environment and that typically kick starts your newborn taking their first breath, as noted by MedlinePlus, a website operated by the U.S. National Library of Medicine. Subsequently, the amniotic fluid drains out of your newborn's lungs or is absorbed from the respiratory system, and that's when your baby should begin breathing on its own.

While the medical community has long observed babies taking their first breath and has researched how to treat post-labor respiratory issues, experts are still pinpointing the exact stimulus that tells a baby to start breathing on its own. "I'm not sure if anyone has an answer for that yet," Dr. Neil Foster, an OB-GYN practicing in Leesburg, Virginia, tells Romper. "We know the mechanics of what happens, but not quite the how." Scientists, however, do have a few theories.

According to the National Center for Biotechnology Information, experiments have indicated that stimulation of the sciatic nerve (the largest single nerve in our body) or the cooling of the skin (called "cutaneous cooling" in science-speak) may initiate a newborn's breathing. Other studies have suggested that the rise of carbon dioxide in the baby's blood will trigger the intake of breath. Until more research is conducted though, the answer as to exactly how your baby knows how to breathe after birth will remain hazy.

As your due date nears, you might be thinking about the amazing transition that your baby will soon undertake. Your newborn will shift from being completely dependent on you to taking their first steps into independence — from drinking to regulating their temperature to taking that very first breath. And while the medical community continues to study how babies know how to breathe post-delivery, it is still an incredible feat to witness.