About premature baby and low birth weight baby

The human embryo has to develop for a period of 40 weeks inside the womb to attain full maturity. Sometimes a woman can give birth to a baby before completing 40 weeks.

There are some normal variations and any delivery after 37 weeks is considered as full term. Any baby born before completing 37 weeks in the womb is called a premature baby.

The normal weight at birth varies widely depending upon many factors like race and maternal body weight. The lowest normal birth weight has been accepted as 2500 grams and any baby weighing less than that is called a low birth weight baby.

A low birth weight baby can be either a premature baby or a full term baby. Full term low birth weight babies have been exposed to some unfavorable factors while developing in the womb like hypertension or some infections in mother during pregnancy.

The advances is bio-electronics have resulted is significant improvement in the care of preterm babies. Most hospitals have a separate unit for such babies.

However preterm babies are very delicate and in spite of excellent care are prone to develop certain complications, which are discussed below. Babies with a gestational age of more than 22 weeks are reported to have survived.

Temperature regulation: Premature babies are extremely sensitive to low temperature. That is why they are looked after in an incubator or a warmer, which maintains the optimal temperature. If suitable ambient temperature is not maintained they will not gain weight and may also develop other complications.

Feeding problem: A preterm baby may not be able to suck from the breast. Hence milk is given through a tube placed inside the stomach.

Those weighing less than 1500 grams or those with some complication may have to be given fluids intravenously for some time.

Respiratory problem: The lungs produce a substance called surfactant, which lowers the surface tension and prevents the alveoli (sac like structures which make up the lungs) from collapsing.

Preterm babies may not have sufficient surfactant. This results in collapse of alveoli and decreased ability of lungs to absorb enough oxygen to meet the requirements of the body. This is a potentially life threatening condition.

Those with severe form of the disease need to be put on ventilators. Today synthetic surfactant is available and can be administered through a tube placed inside the windpipe.

But it is costly and may not be easily available in all places. Those with mild disease may improve with oxygen administration. The immaturity of the respiratory control mechanism can result in temporary cessation of breathing.

Intra-cranial bleeding: The blood vessels of a premature baby are very delicate and sometimes rupture causing bleeding. When this happens inside the brain many complications can arise depending on the part of the brain affected. Even death can occur.

Jaundice: Though majority of newborn babies develop some degree of jaundice in premature babies jaundice can be more severe requiring early intervention.

Learn more about jaundice in newborn babies

Infections: The immaturity of the immune system renders the premature baby highly susceptible to infections.

Metabolic problems: Hypoglycemia (decreased level of sugar in the blood) is common in premature babies due to immaturity of metabolism and can cause convulsions. Decrease in the calcium level is another problem.

Pulmonary hemorrhage: This is more common in low birth weight babies. In this condition there is bleeding into the lungs leading to sudden deterioration in the baby’s condition. The condition is usually fatal.

Necrotizing enterocolitis: This is a serious and potentially fatal condition in which parts of intestine undergo necrosis (necrosis means death). The exact cause is not known. Several factors are thought to contribute.

Asphyxia is one of the factors. Asphyxia means lack of oxygen. If a baby does not cry well soon after birth the tissues do not get sufficient oxygen.

Polycythemia, a condition in which the blood is thicker than normal also predisposes to this condition. Such a blood cannot flow easily and can clot inside the blood vessels causing complete obstruction to blood flow. Heart disease may also predispose to this condition.

The affected baby develops abdominal distention, vomiting and bloody stools. X-ray of abdomen shows air in the walls of intestine.

Treatment consists of withholding oral feeding, intravenous fluids, antibiotics and ventilator support if required. Some babies may require surgery to remove the parts of intestine which has undergone necrosis.

Prognosis: The outcome depends on several factors. Those premature babies weighing more than 2 kilograms rarely have any problem. They may not need any special care except being kept warm. It they are not sucking well it may be necessary to tube feed them.

Those weighing between 1500 and 2000 grams require tube feeding. Some of them may require intravenous fluid for some time. if they do not develop any complications the amount of tube feeds is gradually increased.

Direct breast-feeding may be attempted when the weight is nearing 2000 grams depending on the ability of the baby to suck from the breast. If the baby is sucking well he may be handed over to the mother. Otherwise a few days of tube feeding will be required.

Those weighing less than 1500 grams are very delicate and are prone to develop complications. The most dreaded complications are breathing difficulties, infections and intracranial bleeding.

Though babies weighing less than 1000 grams are being salvaged many of them suffer from permanent disability due to damage to the brain.

It is sometimes not easy to decide whether to go all the way to save such babies or allow them to die. Age of the mother, economic status of parents and willingness of parents to accept the outcome have to be taken into account.

The prognosis for full term low birth weight babies depends on the cause of intrauterine growth retardation. Some diseases in the mother like rubella can cause serious problems in the developing baby. If the low birth weight is only due to low maternal body weight there will not be any problem for the baby.

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