Guidelines for the management of spontaneous preterm labor.

Preterm birth is defined as delivery at <37 completed weeks of pregnancy (World Health Organization). Spontaneous preterm birth (SPB) includes preterm labor, preterm spontaneous rupture of membranes, preterm premature rupture of membranes (PPROM) and cervical weakness; it does not include indicated preterm delivery for maternal or fetal conditions. Early SPB (<32 weeks' gestation) is associated with an increased higher perinatal mortality rate, inversely proportional to gestational age. The pathophysiologic events that trigger SPB are largely unknown but include decidual hemorrhage (abruption), mechanical factors (uterine overdistention or cervical incompetence), and hormonal changes (perhaps mediated by fetal or maternal stress). In addition, several cervicovaginal infections have been associated with preterm labor. SPB is also the leading cause of long-term morbidity, including neurodevelopmental handicap, cerebral palsy, seizure disorders, blindness, deafness and non-neurological disorders, such as bronchopulmonary dysplasia and retinopathy of prematurity. Delaying delivery may reduce the rate of long-term morbidity by facilitating the maturation of developing organs and systems. The benefits of administration of antepartum glucocorticosteroids to reduce the incidence and severity of respiratory distress syndrome may be exploited by delay. Delay may also permit transfer of the fetus in utero to a center with neonatal intensive care unit facilities. There is considerable variation in the way that spontaneous preterm labor (SPTL) is diagnosed, managed and treated internationally. The development of clinical guidelines requires an evidence-based approach to improve outcome and allow more efficient use of resources. With recent advances in our understanding of the etiology and mechanisms of SPTL and the availability of safer, more specific tocolytics, it was felt that guidelines should be developed to achieve, if possible, an European consensus in patient diagnosis, management and treatment.