Differences in Rates and Short-term Outcome of Live Births Before 32 Weeks of Gestation in Europe in 2003: Results From the MOSAIC Cohort

Advances in perinatal medicine increased survival after very preterm birth in all countries, but comparative population-based data on these births are not readily available. This analysis contrasts the rates and short-term outcome of live births before 32 weeks of gestation in 10 European regions. The Models of Organizing Access to Intensive Care for Very Preterm Births (MOSAIC) study collected prospective data on all very preterm births in 10 European regions covering 494,463 total live births in 2003. The analysis sample was live births between 24 and 31 weeks of gestation without lethal congenital anomalies (N = 4908). Outcomes were rates of preterm birth, in-hospital mortality, intraventricular hemorrhage grades III and IV or cystic periventricular leukomalacia and bronchopulmonary dysplasia. Mortality and morbidity rates were standardized for gestational age and gender. Live births between 24 and 31 weeks of gestation were 9.9 per 1000 total live births with a range from 7.6 to 13.0 in the MOSAIC regions. Standardized mortality was doubled in high versus low mortality regions (18%-20% vs 7%-9%) and differed for infants < or = 28 weeks of gestation as well as 28 to 31 weeks of gestation. Morbidity among survivors also varied (intraventricular hemorrhage/periventricular leukomalacia ranged from 2.6% to < or = 10% and bronchopulmonary dysplasia from 10.5% to 21.5%) but differed from mortality rankings. A total of 85.2 very preterm infants per 10,000 total live births were discharged from the hospital alive with a range from 64.1 to 117.1; the range was 10 to 31 per 10,000 live births for infants discharged with a diagnosis of neurologic or respiratory morbidity. Very preterm mortality and morbidity differed between European regions, raising questions about variability in treatment provided to these infants. Comparative follow-up studies are necessary to evaluate the impact of these differences on rates of cerebral palsy and other disabilities associated with preterm birth.