Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 2025 May;311(5):1285-1295.
doi: 10.1007/s00404-024-07909-0. Epub 2025 Jan 28.

Comparison of MRI findings for predicting massive hemorrhage during cesarean section in patients with placental malposition: partial placental volume of lower uterine segment is an accurate and objective indicator

Hiroshi Kuwamura  1 , Takero Terayama  2 , Fumiko Hamabe  3 , Hiromi Edo  1 , Kenta Matsuda  4 , Morikazu Miyamoto  5 , Masashi Takano  5 , Hiroshi Shinmoto  1
Affiliations
Comparative Study

Comparison of MRI findings for predicting massive hemorrhage during cesarean section in patients with placental malposition: partial placental volume of lower uterine segment is an accurate and objective indicator

Hiroshi Kuwamura et al. Arch Gynecol Obstet. 2025 May.

Abstract

Purpose: To comprehensively compare the diagnostic ability and inter-reader agreement of magnetic resonance imaging (MRI) findings for predicting massive hemorrhage after cesarean section in patients with placental malposition, aiming to identify the most reliable and objective indicators.

Methods: Totally, 148 consecutive patients with placental malposition underwent MRI and cesarean section at our hospital between January 2014 and July 2021. The patients were divided into massive and non-massive hemorrhage groups. MRI findings of placenta accreta, placental position, and placental volume were evaluated by two radiologists, and inter-reader agreement was calculated. Diagnostic ability for predicting massive hemorrhage was evaluated using receiver operating characteristic analysis.

Results: Intraplacental T2 dark bands (100% vs. 58.2%, p = 0.001), placental bulge (50% vs. 3.7%, p < 0.001), loss of retroplacental T2 hypointense line (100% vs. 67.2%, p = 0.01), myometrial thinning (92.9% vs. 57.5%, p = 0.009), total placenta previa (64.3% vs. 23.9%, p = 0.033), and anterior placenta (35.7% vs. 10.5%, p = 0.02) were significantly observed in massive hemorrhage group. Partial placental volume of lower uterine segment (PVpartial) was larger in massive hemorrhage group (166 [108-214] cm3 vs. 70 [43-112] cm3 p < 0.001), had the second highest intraclass correlation coefficient (0.84), and had the highest area under the curve (0.81) for diagnosing massive hemorrhage.

Conclusion: This study revealed PVpartial is an accurate and objective indicator for massive hemorrhage, independent of radiologists' experience. This indicator potentially enables prediction of massive hemorrhage, improving pre-operative planning in high-risk pregnancies.

Keywords: Lower uterine segment; Placenta accreta spectrum; Placenta previa; Placental volume.

PubMed Disclaimer

Conflict of interest statement

Declarations. Conflict of interest: The authors have no relevant financial or non-financial interests to disclose. Ethical approval: This study was performed in line with the principles of the Declaration of Helsinki. This study was approved by the Ethics Review Committee of National Defense Medical College Hospital (Certification No. 4441) on July 29, 2021. Consent to participate: The records of all patients during the study period were anonymized prior to the analysis. This study was exempt from obtaining informed consent from all participants. Consent to publish: Not applicable.

Figures

Fig. 1
Fig. 1
Management protocol of placental malposition at our institution. US ultrasonography, MRI magnetic resonance imaging, CS cesarean section, GA gestational age, UAE uterine artery embolization, ICU intensive care unit
Fig. 2
Fig. 2
Evaluation of total placental volume (PVtotal) and partial placental volume of lower uterine segment (PVpartial) with a three-dimensional (3D) workstation software. a Total placental manual segmentation on sagittal magnetic resonance (MR) image. b Partial placental manual segmentation of the lower uterine segment on sagittal MR image. c The lower uterine segment is defined as 6 cm anterior and posterior from the internal cervical os, as shown in this schema. d Volume-rendering image of the total placenta reconstructed using 3D workstation software. PVtotal is calculated as 756.51 cm3 in this case. e Volume-rendering image of the partial placenta of the lower uterine segment reconstructed using 3D workstation software. PVpartial is calculated as 164.68 cm3 in this case
Fig. 3
Fig. 3
Patient flowchart in this study. US, ultrasonography; MRI, magnetic resonance imaging; CS, cesarean section. a Pelvic MRI is performed at approximately 33 weeks of gestation to evaluate placental malposition and accreta. b Massive hemorrhage is defined as > 1000 mL of bleeding within the first 24-h postoperatively
Fig. 4
Fig. 4
Receiver operating characteristic curve of total placental volume (PVtotal) and partial placental volume of lower uterine segment (PVpartial) for massive hemorrhage during cesarean section. Red and blue lines demonstrate PVpartial and PVtotal, respectively
See this image and copyright information in PMC

Similar articles

See all similar articles

References

    1. Bahar A, Abusham A, Eskandar M, Sobande A, Alsunaidi M (2009) Risk factors and pregnancy outcome in different types of placenta previa. J Obstet Gynaecol Can 31:126–131. 10.1016/s1701-2163(16)34096-8 - PubMed
    1. Ishibashi H, Miyamoto M, Soyama H et al (2018) Marginal sinus placenta previa is a different entity in placenta previa: A retrospective study using magnetic resonance imaging. Taiwan J Obstet Gynecol 57:532–535. 10.1016/j.tjog.2018.06.009 - PubMed
    1. Silver RM, Landon MB, Rouse DJ et al (2006) Maternal morbidity associated with multiple repeat cesarean deliveries. Obstet Gynecol 107:1226–1232. 10.1097/01.AOG.0000219750.79480.84 - PubMed
    1. Clark SL, Koonings PP, Phelan JP (1985) Placenta previa/accreta and prior cesarean section. Obstet Gynecol 66:89–92 - PubMed
    1. Tikkanen M, Paavonen J, Loukovaara M, Stefanovic V (2011) Antenatal diagnosis of placenta accreta leads to reduced blood loss. Acta Obstet Gynecol Scand 90:1140–1146. 10.1111/j.1600-0412.2011.01147.x - PubMed

Publication types

LinkOut - more resources