A G4P3 patient with prior three lower-segment cesarean sections is found to have placenta previa on second-trimester ultrasound. MRI shows loss of the hypointense interface between the placenta and myometrium with bulging into the bladder. What specific placentation abnormality and its sub-type does this describe?

• A Placenta accreta — increta variant
• B Placenta previa with vascular lake
• C Circumvallate placenta with sub-chorionic hemorrhage
• D Placenta accreta — percreta variant ✓

Explanation

Placenta accreta spectrum (PAS) disorder describes abnormal placental attachment. The MRI finding of loss of the retroplacental clear zone plus bladder invasion (tenting or bulging into the bladder wall) is diagnostic of placenta percreta — the most severe form where chorionic villi invade through the full myometrial thickness and into adjacent organs (bladder, bowel, broad ligament). Increta invades into but not through the myometrium. Percreta carries the highest risk of intraoperative hemorrhage and requires planned cesarean hysterectomy at a tertiary centre.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.