Chorioamnionitis

Key Points

  • Chorioamnionitis is infection of the amnion and chorion that surround the fetus.
  • Infection usually ascends from vaginal/cervical flora and is commonly associated with group B streptococcal pathways.
  • Major risk factors include prolonged labor, prolonged/premature rupture of membranes, multiple vaginal exams, internal fetal monitors, meconium-stained fluid, and genital-tract bacterial burden.
  • Core diagnostic cues include maternal/newborn fever (38 C or higher), maternal or fetal tachycardia, uterine tenderness, foul-smelling amniotic fluid, and purulent cervical discharge.
  • Maternal complications include dysfunctional labor, uterine atony with hemorrhage risk, endometritis, and sepsis.
  • Neonatal complications include pneumonia, meningitis, and sepsis; early treatment is critical for maternal-neonatal outcomes.

Pathophysiology

Chorioamnionitis develops when microorganisms ascend into the amniotic cavity and infect fetal membranes. Inflammatory response within the intrauterine environment can rapidly involve maternal tissues, placenta, and fetus/newborn.

This process increases risk of uterine dysfunction, hemorrhage, and systemic infection in the birthing patient, while exposing the fetus/newborn to invasive infectious morbidity.

Classification

  • Antepartum/intrapartum intraamniotic infection: Membrane infection identified before or during labor.
  • Maternal-complication pathway: Dysfunctional labor, postpartum uterine atony/hemorrhage, endometritis, and sepsis progression.
  • Neonatal-complication pathway: Pneumonia, meningitis, and neonatal sepsis.

Nursing Assessment

NCLEX Focus

In suspected chorioamnionitis, maternal-fetal trend surveillance and early escalation are priority over isolated single findings.

  • Assess temperature trend and treat fever at or above 38 C (100.4 F) as significant in this context.
  • Monitor maternal and fetal heart rates for tachycardia.
  • Assess uterine tenderness, amniotic-fluid odor, and cervical-discharge characteristics.
  • Assess rupture-of-membrane duration, labor duration, and number of vaginal exams.
  • Monitor for early maternal sepsis progression (mental-status change, hypotension, low urine output, worsening perfusion).
  • Coordinate neonatal-risk communication and readiness due to sepsis/pneumonia/meningitis risk after birth.

Nursing Interventions

  • Notify obstetric team promptly when chorioamnionitis criteria are met or strongly suspected.
  • Initiate ordered broad-spectrum antibiotic therapy promptly and continue through the indicated perinatal period.
  • Maintain continuous maternal-fetal monitoring and frequent reassessment for deterioration.
  • Support infection-source and sepsis workup per protocol (cultures/labs as ordered) without delaying urgent treatment.
  • Prepare postpartum surveillance for hemorrhage, endometritis, and maternal sepsis progression.
  • Communicate neonatal infectious-risk status to newborn team for immediate postbirth assessment and treatment planning.

Maternal-Neonatal Deterioration Risk

Delayed treatment can rapidly increase risk of maternal sepsis and severe neonatal infectious morbidity.

Pharmacology

Drug ClassExamplesKey Nursing Considerations
antibioticsBroad-spectrum intrapartum regimensStart promptly in suspected infection and narrow based on culture/sensitivity when available.
intravenous-fluidsIsotonic fluid support contextSupports perfusion while infection and hemodynamic instability are managed.

Clinical Judgment Application

Clinical Scenario

A laboring patient with prolonged rupture of membranes develops fever of 38.4 C, fetal tachycardia, uterine tenderness, and foul-smelling amniotic fluid.

  • Recognize Cues: Fever, fetal-maternal tachycardia, uterine tenderness, and malodorous fluid.
  • Analyze Cues: Pattern is highly concerning for chorioamnionitis with maternal-neonatal infectious risk.
  • Prioritize Hypotheses: Immediate priority is infection control with prevention of sepsis progression.
  • Generate Solutions: Activate urgent obstetric response, start antibiotics, intensify maternal-fetal monitoring, and coordinate newborn-team readiness.
  • Take Action: Implement treatment protocol and escalate for instability.
  • Evaluate Outcomes: Maternal-fetal status stabilizes and postpartum infectious complications are reduced.

Self-Check

  1. Which findings most strongly support suspected chorioamnionitis during labor?
  2. Why must antibiotics begin promptly even before final culture confirmation?
  3. Which maternal and neonatal complications require highest-priority follow-up?