[Epidemiology of preterm births].

The frequency of preterm birth is about 12-13% in the USA and 5-7% in European countries. In France, almost 13,000 births (1.5%) occur before 32 weeks, 7,000 (0.8%) at 32-33 weeks and 40,000 (5%) between 34 and 36 weeks. Neonatal mortality rates are 10%, 2-3% and 0.5-1% for very, moderate and late preterm infants respectively. Risks of motor and cognitive deficiencies are higher among very (10% and 15% respectively), moderate (4% and 10%) and late preterm children (0.5% and 5%) than among children born at term. Preterm births account for 50% of disabilities from perinatal origin, i.e 3,500 children each year in France. Thus, all preterm infants should be carefully monitored to ensure prompt detection and management of neurodevelopmental impairments. Additional research exploring pathophysiology of preterm birth and its consequences is obviously needed, which will hopefully lead to the development of new therapeutic approaches.