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Neonatal morbidity in moderately preterm infants: a Swedish national population-based study
Maria Altman1, Mireille Vanpée, Sven Cnattingius
1Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.
Insights
Moderately preterm infants (30-34 weeks gestation) face significant risks for neonatal morbidity, including lung disorders and hypoglycemia. These risks increase with lower gestational age, highlighting the need for continued advancements in perinatal care.
Area of Science:
- Neonatal Medicine
- Perinatal Care
- Public Health
Background:
- Infants born between 30 to 34 completed gestational weeks are considered moderately preterm.
- Advances in perinatal care have aimed to reduce neonatal morbidity and mortality.
- Understanding gestational age-specific risks is crucial for optimizing care.
Purpose of the Study:
- To determine gestational age-specific risks for neonatal morbidity in infants born at 30 to 34 completed gestational weeks.
- To investigate the use of interventions in this moderately preterm population.
- To analyze the association between gestational age, birth weight, and neonatal outcomes.
Main Methods:
- Population-based study of 6674 infants born in Sweden between 2004-2008.
- Analysis of risks for neonatal morbidity and interventions based on gestational age and birth weight standard deviation scores.
- Retrospective review of medical records for diagnosed morbidities and treatments.
Main Results:
- High rates of neonatal morbidity were observed: acute lung disorder (28%), hypoglycemia (16%), bacterial infection (15%), and hyperbilirubinemia (59%).
- Intervention rates included antenatal steroids (38%), nasal CPAP (43%), mechanical ventilation (5.5%), surfactant (5.2%), and antibiotics (30%).
- Neonatal morbidity increased significantly with decreasing gestational age, with odds ratios up to 23 at 30 weeks compared to 34 weeks. Low birth weight was associated with higher morbidity.
Conclusions:
- Moderately preterm infants (30-34 weeks gestation) experience substantially increased risks for neonatal morbidity despite advances in perinatal care.
- While overall morbidity rates align with previous reports, the management of respiratory issues shows marked differences from other studies.
- Gestational age-specific risk stratification is essential for targeted interventions and improved outcomes in moderately preterm infants.
Objective:
To determine the gestational age (GA)-specific risks for neonatal morbidity and use of interventions in infants born at 30 to 34 completed gestational weeks.
Study Design:
A population-based Swedish study including 6674 infants born during 2004-2008. Risks for neonatal morbidity and use of interventions were investigated with respect to GA and birth weight standard deviation scores.
Results:
Acute lung disorder was diagnosed in 28%, hypoglycemia in 16%, bacterial infection in 15% and hyperbilirubinemia in 59% of the infants. Thirty-eight percent had received antenatal steroid therapy, 43% nasal continuous positive airway pressure, 5.5% required mechanical ventilation, 5.2% were treated with surfactant, and 30% with antibiotic therapy. Neonatal morbidity rates increased with decreasing GA, with odds ratios for different outcomes ranging from 2.1 to 23 at 30 weeks compared with 34 weeks of GA. Low birth weight standard deviation scores was more common at lower GA and was associated with increased morbidity rates.
Conclusions:
Despite general advances in perinatal care, moderately preterm infants still have substantially increased risks for neonatal morbidity. Whereas the neonatal morbidity rate was similar to results of previous reports, management of respiratory problems differed markedly from other studies.
