A 32-year-old G3P2 with two previous cesarean sections presents at 28 weeks with painless vaginal bleeding. Ultrasound reveals a posterior placenta previa with the placenta extending into the anterior uterine wall scar. MRI shows loss of the normal retroplacental clear zone with irregular lacunae. The most likely diagnosis and the most feared surgical complication are:

• A Placenta previa; uterine atony
• B Vasa previa; fetal exsanguination
• C Placenta accreta spectrum (percreta); bladder or bowel invasion requiring en-bloc resection ✓
• D Placental abruption; consumptive coagulopathy

Explanation

The clinical scenario — multiple prior uterine scars, anterior wall scar with posterior previa, MRI loss of retroplacental clear zone and lacunae — is classic for placenta accreta spectrum, specifically percreta (deepest form) given anterior wall extension on MRI. Percreta invades through the myometrium and serosa, potentially into the bladder or bowel, requiring planned cesarean hysterectomy, possible urology/general surgery assistance, and cell-salvage arrangements. This is the most feared complication in such cases.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.