A new study suggests that use of ultrasound to identify placenta accreta -- a potentially life-threatening condition in which the placenta grows too deeply into the uterine wall -- may not be as accurate as previously believed. Six expert investigators examined ultrasound studies from women who delivered at an academic center between 2000 and 2012, with 55 patients with accreta matched with 56 controls who had placenta previa but no accreta. Ultrasounds were reviewed in random order, with the investigators blinded to clinical history. When compared to results at surgery, ultrasound had a sensitivity as low as 53.5% for the diagnosis of placenta accreta. The authors say that prior studies showing ultrasound sensitivity that exceeds 90% could be affected by single-expert reviewers, suspicion of accreta or knowledge of risk factors. Accurate prediction of placenta accreta is important, the authors say, so that patients and providers can plan appropriately for delivery, including potential scheduled hysterectomy or transfer to a tertiary care center. Read the article (PDF).