Histopathological Comparison of Placentas of Women with High and Normal BMI During Pregnancy

Objective: High body mass index (BMI) during pregnancy has been associated with adverse outcomes for the mother, fetus, and placenta. The effects of these adverse outcomes on the placenta in pregnant women with high BMI have not yet been histomorphologically characterized. Clarifying the effects of high BMI on placental function and determining necessary measures to protect maternal and fetal health is important. The aim of this study is to evaluate the possible structural and functional changes occurring in the placentas of women with normal weight and those with high BMI during pregnancy using hematoxylin-eosin (H&E) staining, and to compare their placentas histopathologically. Materials and Methods: Placental tissues were obtained from 45 normal, healthy pregnant patients with a BMI <30 kg/m² and 45 obese pregnant women with a BMI ≥30 kg/m². All samples underwent routine histological processing and were stained with H&E. Placental sections were examined under a light microscope for villous architecture, syncytiotrophoblast integrity, stromal changes, fibrin deposition, vascular congestion, and syncytial node formation. Results: In H&E staining, while the villus structures in the control group placentas were regular and well-preserved, the high BMI group showed impaired villus integrity, fibrinoid deposition, congestion, stromal edema, and a significant increase in syncytial nodes. Conclusion: High BMI during pregnancy is associated with significant placental histomorphological changes detectable by routine H&E staining. These changes suggest that maternal weight gain damages placental tissue through hypoxic stress and inflammatory responses. Keywords: High body mass index, gestational weight gain, maternal obesity, placenta, histopathology.