[Moderate preterm birth 34-37 weeks: Description of immediate neonatal causes and consequences in a level 2...

In France, 75% of annual preterm births happen between 34 and 36 weeks+6 days. This study's goal is to describe the main causes and short-term consequences.

Two hundred and ninety-seven computerized files of patients who gave birth between 34 and 36 weeks+6 days at the hospital Foch's maternity were analyzed retrospectively. Descriptive statistical analysis was done with XLSTAT 2008.

Among the 6028 births, 4.9% happened between 34 and 36 weeks+6 days and 43.1% of these births were medically induced. The two main causes of induced late preterm birth were: pre-eclampsia (28.9%) and premature rupture of membranes (25%). In spontaneous deliveries, newborns less often require respiratory support at birth (17.2% vs 31%; P=0.02) and are significantly less likely to be hospitalized in neonatology (54% vs 72.3%; P<0.01). C-section rates (71.1% vs 17.75%; P<0.01) and post-partum hemorrhages' probability (10.2% vs 3%; P<0.01) are significantly higher than for medically induced deliveries.

Better knowledge of late prematurity causes and consequences would help limit medically induced births after 34 weeks.