Evaluation of dynamic Computed Tomography (CT) images: A-D, Representative case of postpartum hemorrhage resistant to treatment showing arterial contrast extravasation on dynamic CT (PRACE). Contrast media extravasation into the uterine cavity is observed in the early phase (A and C), with subsequent spread throughout the uterine cavity in the late phase (B and D). E-H, Instance of non-PRACE potentially confused with PRACE. Contrast extravasation into the uterine cavity appears prominent in the early phase, but no contrast diffusion is observed in the late phase (F and H). These images depict partial staining of the anterior uterine wall rather than active bleeding. I-L, Another illustration of non-PRACE with potential for misinterpretation as PRACE. Contrast leakage into the uterine cavity seems evident in the early phase. Subsequent phases reveal mild contrast spreading with well-defined borders, suggesting contrast uptake by the retained placenta. However, no contrast leakage into the uterine cavity is identified. These imaging findings suggest the presence of retained placenta without active hemorrhage. The red line in the sagittal section corresponds with the plane in the transverse section of each case.

Image source: Yamaguchi M, Sagara A, Nagayama Y et al., JAMA Network Open (CC BY 4.0)

News • Preventing maternal death

CT-based indicator helps predict life-threatening postpartum bleeding

Researchers from Kumamoto University have identified a distinctive CT imaging pattern that can predict which women experiencing severe postpartum hemorrhage (PPH) are most likely to need life-saving interventions.

The new finding, termed PRACE (Postpartum hemorrhage, Resistance to treatment, and Arterial Contrast Extravasation), was observed in nearly one-third of patients undergoing dynamic CT scans and was strongly associated with the need for emergency procedures such as uterine artery embolization. The researchers published their findings in JAMA Networ Open.

An anime-style illustration of a pregnant woman lying in an MRI machine, with an IV drip attached to her right arm. She is looking distraught

Postpartum hemorrhage remains a leading cause of maternal death worldwide. While most cases can be managed with medications and basic interventions, a significant number become life-threatening and require more invasive treatment. Until now, there has been no reliable way to identify in advance which cases would prove resistant to standard therapies.

In a nationwide study involving 43 advanced medical centers across Japan, researchers analyzed 352 cases of severe PPH and found that 205 underwent dynamic CT scanning. Of these, 58 cases (32.2%) showed the PRACE pattern, characterized by contrast agent leaking into the uterine cavity during the early phase of imaging—signaling active arterial bleeding.

Patients with PRACE had more than triple the likelihood of needing uterine artery embolization (UAE) compared to those without the finding (86.2% vs. 28.7%), and were more likely to suffer from blood clotting abnormalities and require large-volume transfusions. The presence of PRACE was the single strongest predictor for the need for UAE, with an odds ratio of 27.74. "PRACE is a game-changer in how we assess and respond to critical postpartum bleeding," said Professor Eiji Kondoh of Kumamoto University’s Faculty of Life Sciences. “By using dynamic CT imaging, we can now detect early signs of treatment-resistant bleeding and act swiftly to save lives.”

The researchers suggest that incorporating dynamic CT into emergency obstetric care protocols may significantly improve maternal outcomes. They also propose updating the traditional “4 Ts” classification of postpartum hemorrhage (Tone, Trauma, Tissue, Thrombin) to include a fifth—“CT findings”—to better stratify risk.

Source: Kumamoto University

22.08.2025