Obstetric interventions for babies born before 28 weeks of gestation in Europe: results of the MOSAIC study

Objective To describe obstetric intervention for extremely preterm births in ten European regions and assess its impact on mortality and short term morbidity. Design Prospective observational cohort study. Setting Ten regions from nine countries participating in the 'Models of Organising Access to Intensive Care for Very Preterm Babies in Europe' (MOSAIC) project. Population All births from 22 to 29 weeks of gestation (n = 4146) in 2003, excluding terminations of pregnancy. Methods Comparison of three obstetric interventions (antenatal corticosteroids, antenatal transfer and caesarean section for fetal indication) rates at 22-23, 24-25 and 26-27 weeks to that at 28-29 weeks and the association of the level of intervention with pregnancy outcome. Main outcome measures Use of antenatal corticosteroids, antenatal transfer and caesarean section by two-week gestational age groups as well as a composite score of these three interventions. Outcomes included stillbirth, in-hospital mortality and intraventricular haemorrhage (IVH) grades III and IV and/or periventricular leucomalacia (PVL) and bronchopulmonary dysplasia (BPD). Results There were large differences between regions in interventions for births at 22-23 and 24-25 weeks. Differences were most pronounced at 24-25 weeks; in some regions these babies received the same care as babies of 28-29 weeks, whereas elsewhere levels of intervention were distinctly lower. Before 26 weeks and especially at 24-25 weeks, there was an association between the composite intervention score and mortality. No association was observed at 26-27 weeks. For survivors at 24-25 weeks, the intervention score was associated with higher rates of BPD, but not with IVH or PVL. Conclusions There are large differences between European regions in obstetric practices at the lower limit of viability and these are related to outcome, especially at 24-25 weeks.