Cite this page: Ziadie MS. Accessory lobe / bilobate placenta. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/placentaaccessory.html. Accessed December 19th, 2024.
Accessory lobe
- One or multiple accessory lobes connected to the main disc by blood vessels that are at risk for hemorrhage and thromboemboli
- Seen in 3% of placentas
- Also called succenturiate lobe
- Due to focal noninvolution of chorionic laevae
- Gross description: main placental disc is attached to a smaller portion of placenta by fetal vessels and membranes
Bilobate placenta
- Two lobes of equal size, separated by fetal membranes or connected by narrow isthmus of placental tissue
- Umbilical cord inserts in the membranes between the two discs and is at risk for rupture
- If incompletely removed, there is a risk of maternal postpartum hemorrhage
- Gross description: two lobes of equal size separated by membranes