During the nine months of pregnancy, the baby does not use its lungs to breathe, but does so through the mother. In fact, their lungs will take a long time to mature, and it won’t be until birth that they start working.
Today we talk about the baby’s breathing in the womb , how oxygen reaches it, what circumstances could affect the supply and when the baby begins to breathe on its own.
The baby breathes in the womb through the placenta
When breathing, an exchange of gases occurs in the pulmonary alveoli with the environment, carbon dioxide is discarded and oxygen is captured. During pregnancy, the fetus performs this gas exchange through the placenta, because in the womb its lungs are full of fluid, and therefore inactive.
The placenta is a fundamental organ in pregnancy, since it constitutes the vital connection of the baby with the mother. Its main mission is to transmit nutrients to the baby and act as a ‘fetal lung’ , providing oxygen through the blood.
It is through the umbilical cord that oxygen is transported and carbon dioxide is eliminated. The umbilical cord is made up of a large vein and two smaller arteries: the vein carries oxygenated blood from the mother to the baby , and the arteries carry deoxygenated blood and other wastes in the baby’s blood to the mother.
When do the baby’s lungs mature?
Pulmonary surfactant is a substance present in the lungs that is of great help in the first breath after birth, as it helps to reduce the pressure that the baby has to apply to open the alveoli and that they always remain open and do not close when expelling. the air with each breath.
This substance is present in the fetus at 34 weeks of gestation, which is why, given the risk of premature birth, doctors administer corticosteroids to the mother, which also help to promote the baby’s lung development.
For this reason, one of the main sequelae experienced by late preterm infants (born between weeks 34 and 36 of gestation) are respiratory problems, both in the short and medium term and in the long term, due to their lung immaturity .
How and when the baby begins to breathe on its own
During childbirth, the baby experiences a situation of significant stress and the fluid in its lungs is reabsorbed or expelled through the mouth so that at birth it can take its first breath.
In a normal delivery, the pressure on the baby’s chest as it passes through the birth canal helps eliminate lung fluid, mucus, and amniotic fluid, facilitating breathing.
However, if the baby is delivered by scheduled cesarean section, it is possible that he will have greater difficulty breathing, since his chest has not been compressed along the birth canal . It will take several hours for all the amniotic fluid in the lungs to be completely removed, which is why babies delivered by caesarean section are more likely to sneeze, cough or choke.
Once the baby is born, if the umbilical cord is not cut prematurely, the umbilical cord will continue to provide oxygen to the baby for five to ten minutes, allowing the newborn a calm and relaxed discovery of the outside world.
When the umbilical cord is cut , the vessels are sealed and the baby is ready to breathe on his own.
Situations that can affect the oxygen supply during pregnancy and childbirth
If during pregnancy not enough oxygen reaches the baby , it could see its intrauterine growth affected, present low birth weight or be born earlier than estimated, although in very serious cases the life of the baby could be in danger.
Situations that could compromise the supply of oxygen to the baby during pregnancy are, for example, a knot in the umbilical cord, the aging of the placenta or severe and poorly controlled maternal asthma.
Although many of these situations cannot be prevented, pregnant women can help minimize the risks by eating the right diet, practicing physical exercise (activity during pregnancy has been shown to improve the baby’s lung function) and maintaining healthy lifestyle habits.
It is also important to know that the quality of the air that the pregnant woman breathes directly affects the development of the baby, being associated with a low birth weight and the future appearance of certain diseases.
At the time of delivery there may be some situations that compromise the baby’s oxygen supply or reduce it. In these cases, the body will react by redirecting the little oxygen it receives to the brain and heart, two vital organs. But when the oxygen deficit lasts a long time , the main organs could suffer irreversible damage.
For this reason, medical personnel act as quickly as possible in the event of complicated births or warnings on monitors of loss of fetal well-being, accelerating labor or performing an emergency caesarean section, in order to avoid serious consequences for the baby’s health.
Photos | iStock
In Babies and More | Exercise in pregnancy improves the supply of nutrients and oxygen to the placenta, Meconium aspiration syndrome in the newborn: what it is and what risks it entails, Complications in childbirth: what problems can occur at the time of giving birth