Comparative Analysis of Placental Findings in Gestational Diabetes Mellitus and Pregnancy-Induced Hypertension: A Review

Abstract

Background: The placenta is a vital part of maternal-fetal exchange and optimal intrauterine development. Gestational Diabetes Mellitus (GDM) and Pregnancy-Induced Hypertension (PIH) are the two pregnancy related complications that cause the highest levels of maternal and perinatal morbidity globally. The two conditions have both far reaching but different influences on the placental structure and functioning. GDM is a metabolic disorder, which occurs due to hyperglycemia in the mother; it triggers both structural and vascular alterations as a compensatory response to allow fetal development. Conversely, PIH which is a vascular condition is linked to uteroplacental dysfunction along with ischemia resulting in degenerative placental pathology. These placental changes should be comparatively assessed in order to understand disease pathophysiology, predict perinatal morbidity, and inform maternal-fetal practice.

Material and Methods: The database of PubMed, Scopus, Embase, and Cochrane Library were searched systematically until 2024 with the following keywords placenta, gestational diabetes, pregnancy-induced hypertension, preeclampsia, histopathology, morphometry. They included original research, reviews and meta-analyses that describe gross and microscopic placenta findings in GDM and PIH. Research claiming biochemical, but not histological, analysis was eliminated. Comparisons of extracted data were done to reveal unique and similar features of the placentas in both diseases.

Conclusion: There is a vast difference between placental pathology in both GDM and PIH. Even though the changes of GDM show more of a hyperplastic and hypertrophic type, PIH displays ischemic and degenerative changes. The identification of these patterns can give a clue of the underlying pathophysiology, improve the accuracy of diagnosis, and possibly a basis of antenatal risk stratification. Placental examination is therefore a very important tool to enhance maternal and perinatal outcome.