Nitabuch's and Rohr's fibrinoid layers: Revisiting the interface of the placenta and uterus.

Aim: Nitabuch's and Rohr's fibrinoid layers represent critical but often underrecognized structures at the maternal-fetal interface. This review revisits their historical origins, microscopic features, functional significance, and clinical implications in placental pathology.

Methods: A comprehensive narrative review was conducted using relevant literature sourced from databases including PubMed, Google Scholar, and historical archives. Articles discussing the anatomy, histology, pathological implications, and forensic relevance of Nitabuch's and Rohr's layers were critically reviewed along with their correlations with pregnancy complications.

Results: Nitabuch's layer, historically described as a band of fibrinoid between the basal decidua and cytotrophoblasts, plays a key role in limiting trophoblastic invasion and facilitating placental detachment during delivery. Rohr's fibrinoid, situated beneath the cytotrophoblast layer within the basal plate, is linked with anchoring villi and maternal blood flow regulation. Both layers are formed through complex interactions involving extravillous trophoblasts, maternal decidual cells, and molecular mediators such as matrix metalloproteinases, human leukocyte antigen-G, and transforming growth factor-beta. Aberrations in their development are implicated in conditions like preeclampsia and placenta accreta spectrum, where the absence of Nitabuch's layer correlates with morbid placental adherence. Their recognition can aid in distinguishing normal placental maturation from pathological states and holds potential value in forensic evaluations of retained placenta and unexplained postpartum hemorrhage.

Conclusion: A better understanding of the structure and significance of Nitabuch's and Rohr's layers at the maternal-fetal interface can enhance the interpretation of placental pathology, inform clinical management of obstetric complications, and assist in medico-legal investigations.