The combined exposure to intra-amniotic inflammation and neonatal respiratory distress syndrome increases the risk of intraventricular hemorrhage in preterm neonates

Abstract

Objective: To evaluate the impact of combined exposure to intra-amniotic inflammation and neonatal respiratory distress syndrome (RDS) on the development of intraventricular hemorrhage (IVH) in preterm neonates.

Methods: This retrospective cohort study includes 207 consecutive preterm births (24.0-33.0 weeks of gestation). Intra-amniotic inflammation was defined as an amniotic fluid matrix metalloproteinase-8 concentration >23 ng/mL. According to McMenamin's classification, IVH was defined as grade II or higher when detected by neurosonography within the first weeks of life.

Results: (1) IVH was diagnosed in 6.8% (14/207) of neonates in the study population; (2) IVH was frequent among newborns exposed to intra-amniotic inflammation when followed by postnatal RDS [33% (6/18)]. The frequency of IVH was 7% (8/115) among neonates exposed to either of these conditions - intra-amniotic inflammation or RDS - and 0% (0/64) among those who were not exposed to these conditions; and (3) Neonates exposed to intra-amniotic inflammation and postnatal RDS had a significantly higher risk of IVH than those with only intra-amniotic inflammation [odds ratio (OR) 4.6, 95% confidence interval (CI) 1.1-19.3] and those with RDS alone (OR 5.6, 95% CI 1.0-30.9), after adjusting for gestational age.

Conclusion: The combined exposure to intra-amniotic inflammation and postnatal RDS markedly increased the risk of IVH in preterm neonates.

Keywords: Brain injury; hypoxic-ischemic injury; intra-amniotic inflammation; periventricular-intraventricular hemorrhage; preterm birth.

Figure 1. The rate of the development of intraventricular hemorrhage (IVH) according to the presence or absence of intra-amniotic inflammation and the occurrence of neonatal respiratory distress syndrome (RDS)

Intra-amniotic inflammation was defined as an elevated amniotic fluid MMP-8 concentration (>23 ng/mL). ^*Each P-value was adjusted for gestational age at birth. ^†P-value could not be adjusted for gestational age at birth because no patient without intra-amniotic inflammation and RDS had an IVH. Patients with intra-amniotic inflammation and neonatal RDS had a higher risk of the development of IVH than those with neonatal RDS alone [odds ratio (OR), 5.63; 95% CI, 1.03–30.9; P<0.05] and those with intra-amniotic inflammation alone [OR, 4.56; 95% CI, 1.08–19.3; P<0.05) after adjusting for gestational age at birth.