Placenta (singleton)

Auto text: “Insert Placenta Single”


Placental shapes:

  • Discoid: oval or triangular disc
  • Duplex: bilobed, separated by membrane
  • Bipartite or Tripartite: bidiscoidal or tridiscoidal with incomplete separation
  • Succenturiate: has smaller accessory lobe

Membrane insertions:

  • Marginal: Normal insertion of membranes at the placental edge.
  • Circummarginate: Membranes insert inside the edge (ring of membrane is flat and, unlike normal membrane, does NOT extend to the very edge of the disc)
  • Circumvallate: Membranes insert inside the edge AND fold back onto themselves (a double layer of amnion, chorion, necrotic villi and fibrin form a raised white ring around the surface of the disc)


  1. Examine fetal membranes for color, consistency, translucency.
  2. Trim a strip from the rupture site to the placental margin, and create membrane roll. Submit one section of membrane roll. Remove remainder of membranes from placental disc.
  3. Measure cord length, diameter, distance from margin of placental disc.
  4. Remove cord, lay flat, and examine for number of coils (1-2 every 5 cm is normal; more than 2 per 5 cm is abnormal).
  5. Examine cord for number of vessels. Submit two sections of cord: one 1 cm from cord insertion site, one near fetus.
  6. Measure (3D) and weigh placenta, after membranes and cord have been removed.
  7. Inspect maternal surface, noting any significant areas of disrupted cotyledons, fibrosis or infarct.  Estimate the percentage of disrupted maternal surface.
  8. Serially section the placenta, starting from the maternal surface through to the fetal surface looking for infarcts, hemangiomas or other lesions.
  9. If infarcts or other discrete lesions are noted, they should be characterized, i.e. number, size, location and approximate volume (by percent) of placental tissue involved.
  10. Clinically, if abruption or placenta previa, inspect the placenta for adherent blood clots and marginal hematomas, and check the bucket for large detached hematomas.  Weigh and measure volume of clots.
  11. Submit one cassette of central placenta, one cassette of peri-central placenta (NOT the extreme periphery), and one cassette of multiple thin maternal sections (all from central aspect of disc).  Central and peri-central sections should be full thickness including the chorionic plate, making sure to include fetal vessels.
  12. Submit on the FATS processor for appropriate fixation.
Print Friendly, PDF & Email