Placental histological patterns and uterine artery Doppler velocimetry in pregnancies complicated by early and late pre-eclampsia.

OBJECTIVES: To study placental findings in pregnancies complicated by preeclampsia (PE) and to verify whether these findings are related to gestational age (GA) at PE onset and second trimester uterine artery (UtA) Doppler. METHODS: For all preeclamptic women who delivered at the Department of Obstetrics of Gynecology of the University of Brescia from January 2010 to December 2013 we retrospectively collected data related to placental findings and UtA Doppler velocimetry performed at PE onset. The study cohort was divided into early-onset (EO) PE and late-onset (LO) PE groups. Regression analysis was run to test the predictive ability of UtA Doppler velocimetry for subsequent development of placental lesions after correcting for possible confounders. RESULTS: The LOPE group (n=72) showed placental abnormalities, although with a significantly lower rate if compared to the EOPE one (n=105) (p=0.02). UtA pulsatility index (PI) predicted infarctions (p=0.001), distal villous hypoplasia (p=0.03), decidual arteriolopathy (p=0.03), villous infarcts (p<0.001), syncytiotrophoblast "knots" (p=0.02), microcalcifications (p=0.02), perivillous fibrin deposition (p=0.02) and placental haemorrhage (p=0.01) in the whole study cohort, independently from GA at PE onset. CONCLUSIONS: Similar placental abnormalities were present in both EOPE and LOPE groups although with quantitative differences according to GA and UtA Doppler velocimetry at PE onset. Histological patterns were predicted by UtA PI independently from GA supporting the use of UtA Doppler velocimetry as the key criterion in PE classification.