I’ve always thought about how babies breathe in the womb, and up until today I never understood the mechanism behind it. But now I do, and I’m going to share it with you.
Basically, babies don’t breathe in the womb. Surprise surprise! At least not the way we do. There’s no inhalation of oxygen or exhalation of carbon dioxide.
The mother’s placenta helps the baby breathe while it is growing in the womb. Just like how mothers eat for two, they also breathe for two.
Oxygen and carbon dioxide flow through the blood in the placenta to the baby through the umbilical cord.
Since there is no other way for a fetus (a developing baby) to breathe, problems with the placenta or umbilical cord can result in birth defects or sometimes death.
Do babies get oxygen through the umbilical cord?
Yes, they do. In fact, the umbilical cord is the main source of oxygen for the fetus.
As I said earlier, the umbilical cord serves as the vital lifeline between mother and child.
At 6-7 weeks of pregnancy, the placenta and umbilical cord become the most important organs.
This is because they both allow your baby to develop and receive all the nutrients (oxygen) it needs from you.
In addition to transferring nutrients from the mother to the fetus, the placenta and umbilical cord provide the baby with the oxygen-rich blood required for growth.
With each breath the mother takes, oxygen enters her bloodstream, travels via the placenta and the umbilical cord, and ultimately reaches the baby, whose heart pumps oxygenated blood throughout the body to support the growing and developing baby.
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Lung development in babies
The lungs start to develop between 24 and 36 weeks of pregnancy and end in the third trimester. Until these sacs fully develop, the fetus may have trouble breathing on its own outside of the womb.
The lungs then proceed to grow, with the lungs’ capillaries rapidly expanding and their airways lengthening. This process allows the lungs to acquire the capacity to exchange carbon dioxide and oxygen.
Even when the fetus’s lungs fully develop, it is still impossible for the fetus to breathe until after birth.
Throughout pregnancy, the womb is filled with amniotic fluid, which means that the lungs are filled with it as well.
They begin to inhale little bits of amniotic fluid during weeks 10 and 11 of pregnancy.
This amniotic fluid is essential to allow the lungs to expand and develop appropriately, which means that a fetus cannot drown in the womb.
By the third trimester, the baby will begin to practice breath-like movements, which involve the compression and expansion movements of the lungs, as we understand “breathing.”
Usually…
The baby has at least 4 weeks of breathing practice before being welcomed into the world. This inhalation is more like a swallowing action, which helps the lungs to continue developing.
The breathing practice is a developmental milestone that sets the new baby up for success during their first cry.
The baby’s lungs mature at 36 weeks. By then, the four weeks of breathing practice had been completed.
Within ten seconds of birth, the baby’s first breath sounds like a gasp as the newborn’s central nervous system adjusts to the abrupt change in temperature and surroundings.
The baby’s lungs are full of fluid at birth and are not expanded yet.
Following the baby’s first breath, the baby’s lungs and circulatory system undergo a number of changes. First, the baby’s blood flow resistance increases as more oxygen enters the lungs, and blood flow resistance in the baby’s blood vessels likewise decreases.
Next, fluid drains from the respiratory system. Finally, the baby’s lungs expand and start to function on their own, bringing oxygen into the bloodstream and expelling carbon dioxide through exhalation.
