Complications in the newborn

Risk of infection

While in the uterus, the baby was well protected by the fetal membranes and the antibacterial action of the amniotic fluid in which it was bathed, and by maternal antibodies that cross the placenta and defend it against infections that the mother has already encountered. After birth, antibodies in the colostrum (first milk) and true breast milk, and natural barriers like the baby's skin, give the newborn most of the protection from infection that it has when newly born. Its own immune system will take several months to develop adequately.

Risk of asphyxia

The newborn baby's blood circulation system undergoes major adjustments when it takes its first breath outside the uterus. While the baby is in the uterus, very little blood goes to the lungs because the baby isn't breathing air. The fetal lungs cannot perform the gas exchange (absorbing oxygen and releasing waste carbon dioxide), which occurs from the moment of birth onwards.

Immediately at birth, the blood vessels that bypass the lungs are opened and all the blood in the baby's circulation is then able to pass through the lungs, where it undergoes gas exchange. It is a critical moment for the newborn when the lungs start to function. Failure to breathe is a common reason for birth asphyxia. Also, preterm newborns often have difficulty in getting enough oxygen after birth because their lungs are not fully matured, so gas exchange does not occur effectively.

While in the uterus, the majority of toxic (poisonous) or waste chemicals are cleared from the baby's blood by the placenta, which routes them to the mother's liver, where they are broken down (the process is called detoxification). After the birth, the baby's liver takes over this function, and detoxifies the waste chemicals produced in the body or taken in through the mouth. One of the tasks the liver has to perform is detoxifying a protein called bilirubin released when 'old' red blood cells are broken down. Red blood cells survive for only a short time and are then broken down and replaced. If the newborn's liver is unable to cope with the load of 'old' red blood cells that need to be broken down, bilirubin builds up in the baby's body, giving the skin a yellowish appearance. This condition is called neonatal jaundice, and is most serious when the skin appears yellow on the palms of the hands and soles of the feet.

The newborn's kidneys also make a significant contribution to the clearance of toxic chemicals from the body, which are excreted in the urine. Immaturity in the functioning of the kidneys can also result in newborn complications as toxic chemicals build up in the body.