PROBLEM: In intrauterine infection, inflammatory mediators may be released into the fetal circulation prior to fetal infection. We hypothesize that, in chorioamnionitis, inflammation alters fetal blood vessels. To test this, fetal endothelial cells were examined for vascular cell adhesion molecule (VCAM).
METHOD OF STUDY: Umbilical cords (n=9) from placentas with chorioamnionitis were immunostained for VCAM. Controls from preterm preeclamptic pregnancies (n=7) without histologic inflammation were selected, and matched for gestational age and method of delivery. VCAM sections were reviewed by a pathologist blinded to clinical diagnoses.
RESULTS: All endothelial cells from each of the nine cords from placentas with chorioamnionitis had strong VCAM staining. Two of nine samples also had acute cord vasculitis. No cord endothelial cells from preeclamptic placentas demonstrated similar VCAM staining (p<0.01).
CONCLUSION: Histologic chorioamnionitis was associated with VCAM expression of the umbilical cord vessels. In chorioamnionitis, inflammatory mediators may have entered the fetal circulation to activate endothelial cells. Intrauterine inflammation was not restricted to the chorioamnion, but also involved the fetal circulation.