[Preterm births circumstances in babies born before 35 weeks in French Alpes: PREMALP study]

Objectives: In a regional study of preterm infants born before 35weeks of gestation, the aim was to propose a new classification of preterm births into three groups, and to describe the pregnancy complications and fetal disorders in each group.

Patients and methods: In two areas covered by a perinatal network, all preterm births, live births and stillbirths, which occurred between 22 and 34 completed weeks were recorded over a 21-month period. Each case was classified either in the medically-indicated preterm birth (I) group, or in the accepted spontaneous preterm birth (ASp) group or in the non-accepted spontaneous preterm birth (NASp) group.

Results: One thousand and sixty cases of preterm births were included; among them, 981 were live births or ended with per partum infant death. Forty-nine percent of these births were medically indicated, 32 % were ASp and 19 % were NASp. The distribution of pregnancy complications and fetal disorders differed between preterm birth groups: ischemic placental diseases were present in 38,2 % of medically-indicated births; preterm premature rupture of membranes occurred twice more often in I and ASp preterm births than in NASp preterm births.

Conclusion: This classification is based on the medical decision; it allows to compare medical practices in given obstetrical situations. It appears to be reproducible and easy to use.