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Published on: August 25, 2014
Neonatal outcome associated with singleton birth at 34-41 weeks of gestation
Jean-Bernard Gouyon1, Amélie Vintejoux, Paul Sagot
1Department of Paediatrics, CHU de Dijon, Dijon, France. jean-bernard.gouyon@chu-dijon.fr
Insights
Late-preterm infants born between 34-38 weeks gestation have significantly improved outcomes with each additional week. Maternal complications like hemorrhage and hypertensive disorders impact infant prognosis.
Area of Science:
- Neonatalogy
- Perinatology
- Public Health
Background:
- Late-preterm births (34-36 weeks gestation) comprise 75% of preterm births.
- Previous studies often grouped late-preterm infants, obscuring week-specific outcomes.
- The precise impact of each gestational week on infant prognosis requires further clarification.
Purpose of the Study:
- To investigate the association between gestational age and infant outcomes.
- To determine the contribution of each week of gestation to infant prognosis.
- To identify maternal factors influencing neonatal outcomes.
Main Methods:
- Population-based study of 150,426 singleton neonates.
- Gestational ages ranged from 34 to 41 weeks.
- Multivariate analysis to assess associations between maternal complications and infant outcomes.
Main Results:
- Severe respiratory disorders declined significantly from 19.8% at 34 weeks to 0.28% at 39-41 weeks.
- Each additional week between 34-38 weeks reduced the risk of severe respiratory disorders by 2-3 times.
- Poor prognosis (death/neurological condition) decreased significantly until 38 weeks, then stabilized.
- Antepartum hemorrhage, hypertensive disorders, and diabetes were linked to adverse outcomes.
Conclusions:
- Gestational age is a critical determinant of infant prognosis, particularly up to 38 weeks.
- Maternal complications significantly influence neonatal outcomes.
- Further research should differentiate the roles of gestational age, maternal complications, and delivery induction.
Background:
Approximately 75% of preterm births are late-preterm (34(0/7) to 36(6/7) weeks gestation). This group has usually been considered as a whole in studies assessing the outcome of these preterm infants by comparison with term infants. However, the respective contribution to prognosis of each week of gestation has not been fully clarified.
Methods:
A population-based study of 150 426 live-born singleton neonates with gestational ages ranging from 34 to 41 weeks of gestation.
Results:
The rate of severe respiratory disorders (treated by mechanical ventilation and/or nasal continuous positive airway pressure) markedly declined with gestational age from 19.8% at 34 weeks to 0.28% at 39-41 weeks. Between 34 and 38 weeks, each additional week diminished the relative risk (crude or adjusted) of severe respiratory disorders by a factor varying from 2 to 3. The rate of poor prognosis (death and/or severe neurological condition) significantly declined between 34 and 38 weeks and remained stable thereafter. A multivariate analysis showed that antepartum haemorrhage and hypertensive disorders during pregnancy were significantly associated with severe respiratory disorders and poor outcome. Diabetes was an additional factor associated with severe respiratory disorders.
Conclusions:
Future studies should delineate more precisely the respective contribution of gestational age, maternal complication and induced delivery in the prognosis of infants born between 33 and 39 weeks gestation.
