Normal placental implantation occurs when the placental villi attach to the decidua. However, in Placenta Accreta Spectrum (also known as morbidly adherent placenta) the decidual layer may be defective resulting in the trophoblast invasion into the myometrium of the uterine wall. This topic is important due to the risk of life-threatening hemorrhage.
The spectrum includes:
Use our mnemonic “Accreta Adheres, Increta Invades, and Percreta Perforates” to remember the depth of penetration of the placental villi.