PLACENTAL PATHOLOGY OF ABSENT AND REVERSED END-DIASTOLIC FLOW IN GROWTH-RESTRICTED FETUSES

Objective: To identify placental histopathology associated with absent and reversed end-diastolic Bow demonstrated by umbilical artery (UA) Doppler velocimetry in fetal growth restriction (FGR). Methods: Betwee n January 1989 and June 1995, 64 consecutive, nonanomalous singletons at less than the tenth percentile for birth weight were admitted to th e neonatal intensive care unit, with UA Doppler velocimetry obtained w ithin 3 days of delivery; 54 of the 64 (84%) had placental histopathol ogy. Umbilical artery Doppler wave forms were classified as having end -diastolic flaw (n = 26), and either absent (n = 20) or reversed end-d iastolic Bow (n = 8). Blinded review of placental histology scored les ions in categories of intraplacental vaso-occlusion, uteroplacental va scular pathology, chronic inflammation, and coagulation. Results: Usin g cases of FGR with end-diastolic now present as the control populatio n, we found that absent end-diastolic flow cases had significantly mor e fetal stem vessels with medial hyperplasia and luminal obliteration, and cases of reversed end-diastolic flow had significantly more poorl y vascularized terminal villi, villous stromal hemorrhage, ''hemorrhag ic endovasculitis,'' and abnormally thin-walled fetal stem vessels (ea ch P < .005). Conclusion: In FGR, UA Doppler velocity wave forms do no t demonstrate a continuum of placental lesions in which reversed end-d iastolic Bow reflects more severe placental histopathology than absent end-diastolic flow and end-diastolic flow present. As expected, absen t end-diastolic now cases had more occlusive lesions of the intraplace ntal vasculature. In reversed end-diastolic flow, lesions suggesting v ascular remodeling and/or damage by pathologic conditions of intraplac ental now predominated. (C) 1997 by The American College of Obstetrici ans and Gynecologists.