Factors Associated with Increased Risk of Early Severe Neonatal Morbidity in Late Preterm and Early Term Infants.

Sailesh Kumar,Christopher Flatley,Veronika Schreiber,Jane Fox,Tesfaye S Mengistu

doi:10.3390/jcm10061319

Abstract

Although the risk of neonatal mortality is generally low for late preterm and early term infants, they are still significantly predisposed to severe neonatal morbidity (SNM) despite being born at relatively advanced gestations. In this study, we investigated maternal and intrapartum risk factors for early SNM in late preterm and early term infants. This was a retrospective cohort study of non-anomalous, singleton infants (34+0–38+6 gestational weeks) born at the Mater Mother’s Hospital in Brisbane, Australia from January 2015 to May 2020. Early SNM was defined as a composite of any of the following severe neonatal outcome indicators: admission to neonatal intensive care unit (NICU) in conjunction with an Apgar score <4 at 5 min, severe respiratory distress, severe neonatal acidosis (cord pH < 7.0 or base excess <−12 mmol/L). Multivariable binomial logistic regression analyses using generalized estimating equations (GEE) were used to identify risk factors. Of the total infants born at 34+0–38+6 gestational weeks, 5.7% had at least one component of the composite outcome. For late preterm infants, pre-existing diabetes mellitus, instrumental birth and emergency caesarean birth for non-reassuring fetal status were associated with increased odds for early SNM, whilst for early term infants, pre-existing and gestational diabetes mellitus, antepartum hemorrhage, instrumental, emergency caesarean and elective caesarean birth were significant risk factors. In conclusion, we identified several risk factors contributing to early SNM in late preterm and early term cohort. Our results suggest that predicted probability of early SNM decreased as gestation increased.

Highlights

The causes of severe neonatal morbidity (SNM) are multifactorial, gestational age at birth is a major contributor to its development [1,2,3]
The overall prevalence of early SNM was 5.7% (354/6243) with a higher proportion seen in late preterm (172/950, 18.1%) compared to early term (182/5293, 3.4%) infants (Figure 1)
After adjusting for all confounders identified by univariable analysis, we found that pre-existing diabetes, instrumental birth and emergency CS for NRFS were associated with higher odds of early SNM in late preterm infants

Summary

Introduction

The causes of severe neonatal morbidity (SNM) are multifactorial, gestational age at birth is a major contributor to its development [1,2,3]. Intrapartum and neonatal care have resulted in significant improvements in birth outcomes a reduction in neonatal mortality, prevention of SNM remains challenging. It is known that SNM is associated with higher risk of perinatal death [1,2,3], some cohorts of infants are vulnerable—those that are preterm, growth restricted or small or large for gestational age and those with hypoxic intrapartum events requiring operative birth. Preterm birth rates even in high-income countries (HIC) [2,3] continue to rise and it remains a very strong predictor of neonatal morbidity [3,10]. Late preterm birth in particular is a major contributor [11,12] accounting for up to 72% of all preterm births [13,14]

Methods

Results

Discussion

Conclusion