During the nine months of pregnancy, the baby breathes through the mother. The baby's lungs are the last organ to start functioning, and it will be like this after birth.
During pregnancy, the mother's breathing transforms and captures more oxygen since you have to breathe for two. The baby takes the necessary oxygen through the blood, your respiratory system is prepared to carry between 20 and 30% more oxygen than that of an adult. It is through the umbilical cord, where oxygen is transported and carbon dioxide is removed.
Mother and son are together but not scrambled, the maternal and fetal blood are never in direct contact, the exchange occurs in the placenta. The placental membrane is crossed by oxygen and carbon dioxide, in addition to other substances that the baby needs for its development. The oxygen that reaches the baby through the mother is not very abundant, since it has had to pass through her blood, it is for this reason that the baby's hemoglobin, to take advantage of the oxygen to the maximum, transports between 20 and 30% more oxygen than the mother's blood, and its hemoglobin concentration is 50% higher.
When the baby does not get enough oxygen during pregnancy, whether due to a lump in the umbilical cord, aging of the placenta ... then there is a decrease in fetal growth, but if the lack of oxygen occurs at the end of the pregnancy, during the Childbirth can lead to hypoxia, with possible irreversible effects on the baby's brain.
When the baby is born, its ductus arteriosus that connects its pulmonary arteries and aorta, closes just when the lungs expand with the first breaths. The vessels are filled with blood and the pressure on the left atrium also closes the hole of Botal, this hole communicates the two atria of the heart during its stay inside the mother and which never reopens.
When the umbilical cord is cut and knotted, the vessels are sealed and the baby is ready to breathe on his own.
