Impact of prematurity on perinatal mortality and morbidity.

Severe prematurity is a prime factor causing perinatal mortality or morbidity. In Finland 1% of babies are born before 32 completed weeks of pregnancy and 0.9% are delivered with a birth weight of 1500 g or less. Since transport of a baby in utero is preferable to transporting a neonate, approximately 85% of infants below 1000 g and 90% of infants between 1000 to 1499 g are delivered in departments with facilities for neonatal intensive care. The rate of caesarean delivery is approximately 50% in pregnancies between 26 and 28 weeks, while the overall caesarean section rate is 15%. Deaths of low birth weight babies account for 66% of the total perinatal mortality and those of very low birth weight babies 46%. Intrauterine deaths constitute two thirds and neonatal deaths one third of perinatal mortality among very low birth weight babies. In Turku, neonatal survival rate for infants of 500 to 749 g was 61.5% and for infants of 750 to 999 g, 77.3%. In Turku respiratory distress syndrome is one of main complications of prematurity that has led to death in 11.2% of infants in recent years. Of the survivors, 85% have been healthy at the age of two years. The incidence of the bronchopulmonary dysplasia among very low birth weight infants has been 19.7%. In recent years, the incidence of severe brain haemorrhage has been 32% among infants with a birth weight below 1000 g.