Prematurity

Birth of a baby before 37 weeks’ gestation. The premature infant may not be sufficiently developed to cope with independent life and needs special care. About 5–10 per cent of babies are born prematurely. Some 40 per cent of premature deliveries occur for no known reason. The remainder are due to conditions such as pre-eclampsia, hypertension, diabetes mellitus, long-standing kidney disease, and heart disease. Other causes are antepartum haemorrhage, intrauterine infection, or premature rupture of membranes. A common cause is multiple pregnancy (see pregnancy, multiple). A premature infant is smaller than a full-term baby, lacks subcutaneous fat, is covered with downy hair ( lanugo), and has very thin skin. The baby’s internal organs are also immature. The major complication is respiratory distress syndrome. There is increased risk of brain haemorrhage, jaundice, and hypoglycaemia. The baby has a limited ability to suck and maintain body temperature, and is prone to infection. The earlier a baby is born, the more likely it is to have such problems. Premature infants are usually nursed in a special baby unit that provides intensive care. The baby is placed in an incubator, and may have artificial ventilation to assist breathing, artificial feeding through a stomach tube or into a vein, and treatment with antibiotic drugs and iron and vitamin supplements. With modern techniques, some infants survive even if they are born as early as 24 weeks’ gestation.