Placenta

Author: Mikael Häggström

Gross processing

• Determine the shape of the placenta
• Look for any accessory lobes
• Determine the completeness of placental membranes, opacity, color and consistency (slimy/slippery?)
• Determine point of rupture from nearest margin
• Note where the membranes are inserted
• Examine the umbilical cord

• Measure the distance between the insertion point and the nearest placental margin
• Measure the cord length and give proximal and distal diameter
• Count the number of vessels away from the insertion

• Weigh the trimmed disk, after having trimmed away the cord and membranes, and after having removed excess amounts of loose retroplacental blood clots over the maternal surface.
• Examine the fetal surface (chorionic plate):

• Note its color
• Look for any pathologies including granular excrescences, subchorionic fibrin or subamniotic hemorrhage
• Look at the integrity and extent of the vasculature, including any thrombosis and traumatic damage

• Examine the maternal surface (basal plate) for completeness, adherent blood clots, depressions, calcifications and fibrin
• Take membrane rolls and cord sections, before sectioning the placenta
• With the fetal surface down on the cutting board, cut the placenta at 1cm intervals so that it can be reconstructed
• Palpate the parencyhmal sections for areas of induration.
• Note the color of the parenchyma and describe any pale areas, cysts, infarcts (estimate total amount of infarcted tissue), thrombi, increased fibrin and calcifications

Tissue selection

• Distal (toward fetus) membrane roll and cross section of distal cord
• Proximal (toward placenta) membrane roll and cross section of proximal cord ( 2-3 cm from insertion)
• Placental section including fetal surface ( full thickness if possible)
• Placental section including maternal surface (full thickness if possible)
• Any lesions or abnormalities

Main page

• Main page of Patholines