Histopathological Evaluation of Placental Changes in Women with Excessive Gestational Weight Gain

Objective: Excessive weight gain during pregnancy has been associated with adverse maternal and fetal outcomes; however, its effects on placental histomorphology remain incompletely characterized. The present study aimed to evaluate placental histopathological alterations in women who gained excessive weight during pregnancy using Hematoxylin–Eosin (H&E) staining. Materials and Methods: Placental tissues were obtained postpartum from 45 normal-weight pregnant women (BMI <30 kg/m²) and 45 women with excessive gestational weight gain/obesity (BMI ≥30 kg/m²). All samples underwent routine histological processing and were stained with H&E. Placental sections were examined under light microscopy for villous architecture, syncytiotrophoblast integrity, stromal changes, fibrin deposition, vascular congestion, and syncytial knot formation. Results: Placentae from the control group exhibited preserved villous architecture, intact syncytiotrophoblast layers, and normal stromal and vascular morphology. In contrast, placentae from the high-BMI group demonstrated marked histopathological alterations, including villous structural disorganization, stromal degeneration, increased fibrin deposition, prominent vascular congestion, and an increased number of syncytial knots. Conclusion: Excessive weight gain during pregnancy is associated with significant placental histomorphological alterations detectable by routine H&E staining. These structural changes may reflect impaired uteroplacental circulation and reduced placental functional capacity, potentially contributing to an adverse intrauterine environment. Keywords: Gestational weight gain, placenta, hematoxylin–eosin, histopathology, villous degeneration