Neonatal Outcome of Extremely Small Low Birth weight Liveborn Infants Below 901 g in a Swedish Population

Abstract

In a regional population of 32,120 liveborn newborn infants 65 (0.2%) had a birthweight less than or equal to 900 g (extremely small low birthweight = ESLBW) with mean gestational age 26.4 (range 22-31) completed weeks of gestation. The total 0-1 year survival rate was 48%. For the 42 infants treated in the Level III regional neonatal intensive care unit (NICU) the 0-1 year survival rate was 55% versus 34% for 23 infants not transferred to the Level III unit. In the ESLBW infants treated in the regional NICU the major complications were respiratory disorders requiring artificial ventilation (73%), bronchopulmonary dysplasia (26%), intracranial haemorrhages (40%), symptomatic persistent ductus arteriosus (36%) and sepsis (14%), persistent retinopathy of prematurity (8%). Duration of NICU treatment was 51 days (range 10-95) for survivors. Mode of delivery and rate of perinatal complications did not differ between survivors and non-survivors. Previous legal abortion occurred in 24%, fertility problems in 29% and 21% of the mothers were immigrants. Otherwise no significant abnormalities were found in maternal or socioeconomic conditions. Factors deciding neonatal outcome in the tiniest babies seem to be a combination of prenatal circumstances and neonatal minute fine care procedures.