Histopathological Characteristics of Placenta in Pregnancies Complicated by Intrauterine Growth Restriction-A Pilot Study.

Background/

Objectives

Intrauterine growth restriction (IUGR) is a condition in which a fetus does not reach its normal growth potential and is associated with increased neonatal morbidity. Surveillance relies on cardiotocography, a biophysical ultrasound, and a Doppler assessment, but placental pathology remains insufficiently integrated into clinical evaluations. This study aimed to compare placentas from IUGR and normal pregnancies.

Methods

This cohort included 34 pregnancies (16 IUGR, 18 controls) managed at Hunedoara County Hospital (Romania). The ultrasound and Doppler parameters were documented. The placentas were collected after delivery, fixed in formalin, and processed using standard histopathological protocols. The villous morphology and maternal vascular malperfusion features were assessed on H&E sections, focusing on syncytial knots, villous caliber reduction, stromal fibrosis, fibrin deposition, and infarctions. Immunohistochemistry for CD34, cytokeratin 7 (CK7), CD68, vascular endothelial growth factor (VEGF), and Hypoxian inducible factor 1 (HIF-1α)was performed using a semi-quantitative 0-3 scoring system. A statistical analysis was performed using chi-squared testing for categorical variables and t-tests for continuous variables.

Results

The ultrasound evaluation showed an estimated fetal weight below the 10th percentile and abnormal Doppler indices in the IUGR group. The histopathology demonstrated a strong association between IUGR and villous abnormalities, including an increased number of syncytial knots, stromal fibrosis, a reduced villous caliber, and placental infarctions. The immunohistochemistry showed a marked overexpression of VEGF and HIF-1α and increased CD68-positive Hofbauer cells in IUGR placentas (p < 0.0001), while CD34 and CK7 displayed preserved strong staining in both groups.

Conclusions

Placentas from IUGR pregnancies exhibited advanced maternal vascular malperfusion with consistent hypoxic and inflammatory changes, correlating with Doppler alterations. These findings highlight the diagnostic relevance of placental pathology in pregnancies with IUGR.