Chorioamnionitis and Risk for Maternal and Neonatal Sepsis: A Systematic Review and Meta-analysis

Abstract

Objective: To estimate the risk of maternal and neonatal sepsis associated with chorioamnionitis.

Data sources: PubMed, BIOSIS, and ClinicalTrials.gov databases were systematically searched for full-text articles in English from inception until May 11, 2020.

Methods of study selection: We screened 1,251 studies. Randomized controlled trials, case-control, or cohort studies quantifying a relationship between chorioamnionitis and sepsis in mothers (postpartum) or neonates born at greater than 22 weeks of gestation were eligible. Studies were grouped for meta-analyses according to exposures of histologic or clinical chorioamnionitis and outcomes of maternal or neonatal sepsis.

Tabulation, integration, and results: One hundred three studies were included, and 55 met criteria for meta-analysis (39 studies of preterm neonates, 10 studies of general populations of preterm and term neonates, and six studies of late preterm and term neonates). Study details and quantitative data were abstracted. Random-effects models were used to generate pooled odds ratios (ORs); most studies only reported unadjusted results. Histologic chorioamnionitis was associated with confirmed and any early-onset neonatal sepsis (unadjusted pooled ORs 4.42 [95% CI 2.68-7.29] and 5.88 [95% CI 3.68-9.41], respectively). Clinical chorioamnionitis was also associated with confirmed and any early-onset neonatal sepsis (unadjusted pooled ORs 6.82 [95% CI 4.93-9.45] and 3.90 [95% CI 2.74-5.55], respectively). Additionally, histologic and clinical chorioamnionitis were each associated with higher odds of late-onset sepsis in preterm neonates. Confirmed sepsis incidence was 7% (early-onset) and 22% (late-onset) for histologic and 6% (early-onset) and 26% (late-onset) for clinical chorioamnionitis-exposed neonates. Three studies evaluated chorioamnionitis and maternal sepsis and were inconclusive.

Conclusion: Both histologic and clinical chorioamnionitis were associated with early- and late-onset sepsis in neonates. Overall, our findings support current guidelines for preventative neonatal care. There was insufficient evidence to determine the association between chorioamnionitis and maternal sepsis.

Systematic review registration: PROSPERO, CRD42020156812.

Figure 1.

Flow diagram of the study selection process.

Figure 2.

The unadjusted odds of early-onset neonatal sepsis in relation to histological chorioamnionitis. All studies were conducted in preterm only neonates unless otherwise indicated. *Combined preterm and term neonate study. ^†Numbers represent a composite definition of all confirmed or presumed early-onset neonatal sepsis cases unless otherwise indicated. ^‡Term (>37 weeks of gestation) only neonate study. ^§Numbers represent all presumed cases based off clinical criteria, and it is unclear whether some of those cases were also confirmed through a positive test culture. HCA, histological chorioamnionitis; EONS, early-onset neonatal sepsis.

Figure 3.

The unadjusted odds of confirmed early-onset neonatal sepsis in relation to clinical chorioamnionitis. *Numbers to calculate the odds ratio were obtained from the corresponding study author and represent unpublished data. ^†Studies included all neonates born ≥22 weeks of gestation. ^‡Studies included neonate populations that were born at ≥34 weeks of gestation. CCA, clinical chorioamnionitis; EONS, early-onset neonatal sepsis.

Figure 4.

The unadjusted odds of any early-onset neonatal sepsis in relation to clinical chorioamnionitis. Numbers represent a composite definition of any confirmed or presumed early-onset neonatal sepsis cases for each respective study. *Studies included all neonates born ≥22 weeks of gestation. ^†Studies included neonate populations that were born at ≥34 weeks of gestation. CCA, clinical chorioamnionitis; EONS, early-onset neonatal sepsis.

Figure 5.

The unadjusted odds of confirmed late-onset neonatal sepsis in relation to histological chorioamnionitis in preterm neonates. HCA, histological chorioamnionitis; LONS, late-onset neonatal sepsis.

Figure 6.

The unadjusted odds of confirmed late-onset neonatal sepsis in relation to clinical chorioamnionitis among preterm neonates. *Numbers for odds ratio calculations were obtained from the corresponding study author and represent unpublished data. CCA, clinical chorioamnionitis; LONS, late-onset neonatal sepsis.