Preterm labour and prematurity

Spontaneous preterm birth includes deliveries following preterm labour with intact membranes and deliveries following preterm pre-labour rupture of the membranes. These account for approximately two thirds of preterm births, and therefore represent the predominant cause of perinatal mortality and morbidity. To achieve significant reductions in perinatal and neonatal mortality and morbidity, clinicians must focus their efforts on the earliest births, particularly those before 30 weeks gestation. As well as the prognosis, the aetiology underlying spontaneous prematurity varies with gestational age. This article reviews the risk factors associated with early delivery along with potential methods of screening and risk reduction. The need for accurate diagnosis is stressed along with the appropriate but not overzealous application of interventions. The potential harmful effects of many of the commonly used interventions are emphasised.