Related Experiment Video
Updated: Feb 8, 2026

A Novel Method for Involving Women of Color at High Risk for Preterm Birth in Research Priority Setting
Published on: January 12, 2018
Subclinical and clinical chorioamnionitis, fetal vasculitis, and risk for preterm birth: A cohort study
Kristin Palmsten1, Katharine K Nelson2, Louise C Laurent3
1HealthPartners Institute, Mail Stop: 23301A, P.O. Box 1524, Minneapolis, MN, 55440, United States; Department of Pediatrics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, United States.
Objective:
To evaluate the association between subclinical and clinical chorioamnionitis and risk of preterm birth (PTB).
Methods:
Demographic and clinical characteristics were abstracted from medical records and placental examinations performed (N = 1371 pregnancies including spontaneous and medically-indicated PTBs). Pregnancies were classified as having clinical chorioamnionitis (with or without histologic chorioamnionitis), subclinical chorioamnionitis (histologic, but not clinical, chorioamnionitis), or no chorioamnionitis; pregnancies with histologic chorioamnionitis were further evaluated for fetal vasculitis. Relative risks for PTB, early and late PTB, and PTB ± premature rupture of membranes (PROM) were adjusted for maternal characteristics.
Results:
Clinical (4.3%) and subclinical (24.5%) chorioamnionitis were not associated with PTB overall. In pregnancies without clinical or subclinical chorioamnionitis, the risk of PTB with PROM and early PTB was 2.2% and 8.6%, respectively. In comparison, clinical chorioamnionitis was associated with an increased risk of PTB with PROM (aRR: 3.42 (95%CI: 1.07, 10.98), whereas subclinical chorioamnionitis was associated with increased risk of PTB with PROM (aRR: 3.92 (95% CI: 2.15, 7.12)) and early PTB (aRR: 1.77 (95% CI: 1.18, 2.64)). Histologic chorioamnionitis with fetal vasculitis was associated with increased risk of PTB with PROM (aRR: 7.44 (95% CI: 3.68, 15.05)) and early PTB (aRR: 2.94 (95% CI: 1.78, 4.87)), whereas histologic chorioamnionitis without fetal vasculitis was associated with increased risk of PTB with PROM only (aRR: 2.64, 95% CI: 1.27, 5.50).
Conclusions:
Subclinical chorioamnionitis and histologic chorioamnionitis with fetal vasculitis were associated with early PTB and PTB with PROM but not with PTB overall, likely due to inclusion of indicated PTBs.
More Related Videos
08:50A Murine Model of Fetal Exposure to Maternal Inflammation to Study the Effects of Acute Chorioamnionitis on Newborn Intestinal Development
Published on: June 24, 2020
05:53Candidate Gene Testing in Clinical Cohort Studies with Multiplexed Genotyping and Mass Spectrometry
Published on: June 21, 2018
Related Concept Videos
Birth Control Methods
Aneurysm II: Clinical Manifestations and Diagnostic Studies
Relative Risk
Fetal Circulation
Two umbilical arteries transport blood from the fetus to the placenta. At the placenta, the blood absorbs oxygen and nutrients while simultaneously eliminating waste products. This oxygen-enriched and nutrient-rich blood then returns to the fetus through one...
Hypertension III: Clinical Manifestations and Diagnostic Studies
Venous Thrombosis II: Clinical Manifestations and Diagnostic Studies