Nomogram based on clinical characteristics and ultrasound indicators for predicting severe postpartum hemorrhage in patients with anterior placenta previa combined with previous cesarean section: a retrospective case-control study.

BACKGROUND: Placental accreta spectrum disorders (PAS) are a high-risk group for severe postpartum hemorrhage (SPPH), with the incidence of PAS increasing annually. Given that cesarean section and anterior placenta previa are the primary risk factors for PAS, therefore, our study aims to investigate the predictive value of clinical characteristics and ultrasound indicators for SPPH in patients with anterior placenta previa combined with previous cesarean section, providing a theoretical basis for early prediction of SPPH. METHODS: A total of 450 patients with anterior placenta previa combined with previous cesarean section were retrospectively analyzed at Shengjing Hospital affiliated with China Medical University between January 2018 and March 2022. Clinical data and ultrasound indicators were collected. Patients were categorized into SPPH (blood loss >2000mL, 182 cases) and non-SPPH (blood loss ≤ 2000mL, 268 cases) groups based on the blood loss within 24 h postpartum. The population was randomly divided into training and validation cohorts at a 7:3 ratio. LASSO and multifactorial logistic regression analyses were utilized to identify independent risk factors for SPPH. Accordingly, a nomogram prediction model was constructed, the predictive performance was assessed using receiver operating characteristic (ROC) curves, calibration curves and decision curve analysis (DCA). RESULTS: Among the 450 patients, 182 experienced SPPH (incidence rate, 40.44%). Preoperative systemic immune-inflammatory index, preoperative D-dimer level, preoperative placenta accreta spectrum ultrasound scoring system (PASUSS) score, and one-step-conservative surgery were identified as independent risk factors for SPPH in patients with anterior placenta previa combined with previous cesarean section. A nomogram was constructed based on these factors. The areas under the ROC curves for the training and validation cohorts were 0.844 (95%CI: 0.801-0.888) and 0.863 (95%CI: 0.803-0.923), respectively. Calibration curves and DCA indicated that this nomogram demonstrated good predictive accuracy. CONCLUSIONS: This nomogram presents an effective and convenient prediction model for identifying SPPH in patients with anterior placenta previa combined with previous cesarean section. It can guide surgical planning and improve prognosis.

The predictive value of conventional magnetic resonance imaging combined with intravoxel incoherent motion parameters for evaluating maternal and neonatal clinical outcomes in patients with placenta accreta spectrum disorders.

INTRODUCTION: We aimed to identify factors predictive of adverse maternal and neonatal outcomes in patients with placenta accreta spectrum (PAS) disorders using magnetic resonance imaging (MRI) and intravoxel incoherent motion (IVIM) parameters. METHOD: Fifty-six normal singleton pregnancies at 33-39 weeks of gestation underwent MRI examination at 1.5 T. The IVIM parameters were obtained from the placenta. The correlation between the f value and postpartum hemorrhage (PPH) and between the f value and transfused units of red blood cells (RBCs) was estimated by linear regression. The correlation between various influencing factors (clinical risk factors, MRI features, and IVIM parameters) and poor outcomes was investigated using univariate and multivariate analyses. RESULT: The interobserver agreement ranged from fair to excellent (k = 0.30-0.88). Multivariate analyses showed that previous cesarean sections, low signal intensity bands on T2WI and the D value were independent risk factors for adverse outcomes. The combination of three risk factors demonstrated the highest AUC of 0.903, with a sensitivity and specificity of 73.10 % and 96.90 %, respectively. Last, f was positively correlated with PPH and units of RBCs transfused. DISCUSSION: Preoperative MRI features and IVIM parameters may be used to predict poor outcomes in patients with invasive placental disorders like PAS.

The MRI estimations of placental volume, T2 dark band volume, and cervical length correlate with massive hemorrhage in patients with placenta accreta spectrum disorders.

PURPOSE: To identify whether placental volume, T2 dark band volume, and cervical length measured by MRI correlate with massive hemorrhage (MH) in patients with placenta accreta spectrum (PAS) disorders. METHODS: A total of 163 pregnant women with PAS underwent preoperative MRI examination were divided into MH group and non-MH group. The placental volume, T2 dark band volume, and cervical length of PAS patients were measured and evaluated their ability to identify MH in patients with PAS. RESULTS: Patients with MH had a significantly larger placental volume, larger T2 dark band volume, and shorter cervical length than patients without MH (all P < 0.001). Multivariable logistic regression showed that placental volume (> 890 cm3), T2 dark band volume (> 35 cm3), and cervical length (< 30 mm) were significant independent risk factor in identification of MH. In all PAS patients, a positive linear correlation was found between placental volume and amount of blood loss (r = 0.527), and between T2 dark band volume and amount of blood loss (r = 0.642), and a negative linear correlation was found between cervical length and amount of blood loss (r = - 0.597). When combined with the three MRI indicators, the sensitivity and specificity in identifying cases at high risk for MH were 91.638% and 94.051%, respectively, with area under the curve (AUC) of 0.923. CONCLUSION: The placental volume, T2 dark band volume, and cervical length might be used to predict MH in patients with PAS.

Imaging of Antepartum and Postpartum Hemorrhage.

Severe obstetric hemorrhage is a leading cause of maternal mortality and morbidity worldwide. Major hemorrhage in the antepartum period presents potential risks for both the mother and the fetus. Similarly, postpartum hemorrhage (PPH) accounts for up to a quarter of maternal deaths worldwide. Potential causes of severe antepartum hemorrhage that radiologists should be familiar with include placental abruption, placenta previa, placenta accreta spectrum disorders, and vasa previa. Common causes of PPH that the authors discuss include uterine atony, puerperal genital hematomas, uterine rupture and dehiscence, retained products of conception, and vascular anomalies. Bleeding complications unique to or most frequently encountered after cesarean delivery are also enumerated, including entities such as bladder flap hematomas, rectus sheath and subfascial hemorrhage, and infectious complications of endometritis and uterine dehiscence. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material. See the invited commentary by Javitt and Madrazo in this issue.

The value of the combined MR imaging features and clinical factors Nomogram model in predicting intractable postpartum hemorrhage due to placenta accreta.

To explore the value of the combined MR imaging features and clinical factors Nomogram model in predicting intractable postpartum hemorrhage (IPH) due to placenta accreta (PA). We conducted a retrospective study with 270 cases of PA patients admitted to our hospital from January 2015 to December 2022. The clinical data of these patients were analyzed, and they were divided into 2 groups: the IPH group and the non-IPH group based on the presence of IPH. The differences in data between the 2 groups were compared, and the risk factors for IPH were analyzed. A Nomogram model was constructed using independent high-risk factors, and the predictive value of this model for IPH was analyzed. The results of multivariable binary Logistic regression analysis showed higher number of cesareans, placenta previa, placenta accreta type (implantation, penetration), low signal strip on T2 weighted image (T2WI) were independent high-risk factor for IPH (P < .05). ROC analysis and Hosmer-Lemeshow goodness-of-fit test showed the Nomogram predictive model constructed with the high-risk factor has good discrimination and calibration. Decision curve analysis (DCA) showed that when the probability threshold for the Nomogram model's prediction was in the range from 0.125 to 0.99, IPH patients could obtain more net benefits, making it suitable for clinical application. The higher number of cesareans, placenta previa, placental accreta type (implantation, penetration), and low signal strip on T2WI are independent high-risk factor for IPH. The Nomogram predictive model constructed with the high-risk factor demonstrates good clinical efficacy in predicting the occurrence of IPH due to PA.

Prediction of bleeding in placenta accrete spectrum with lacunar surface: a novel aspect.

PURPOSE: Diagnosing the placenta accreta spectrum is crucial to prevent morbidities and mortalities among women with the suspicion of this pathology. We aim to evaluate novel ultrasonography markers for these patients in diagnosing and predicting prognosis. METHODS: This cross-sectional study was performed in a referral academic hospital. The population was composed of 51 pregnant women with a suspect of placenta accreta spectrum who had scheduled C-sections. Their primary information and past medical histories were documented. Then the ultrasonography markers, including the most bulging volume behind the bladder (area, perimeter, and volume), the Lacune (diameter, length, number, and surface of the largest lacuna obtained by multiplying the length by the width), the most considerable thickness of placenta on the cervix in patients with placenta previa, the most considerable thickness of the placenta behind the bladder, the Jellyfish sign, and sponge cervix were evaluated. Their comparison to the severity of the bleeding, the rate of the hysterectomy, and the following pathology of the placenta accreta spectrum were analyzed. RESULTS: The results showed that 17 (33.3%) of patients had severe bleeding (more than 2500 cc). The diameter, length, and surface of the largest lacunae limited to women with severe bleeding were 13.50 (5.5-21) mm, 20.50 (11-56) mm, 273.00 (60-1176) mm2, and they were 11.00 (5-24) mm, 16.25 (10-39) mm, and 176.25 (50-744) mm2 for women without severe bleeding (P value = 0.039, 0.027, 0.021). 13 (76.5%) women with severe bleeding had Jellyfish signs,16 (94.2%) had bulging on the cervix, and 10(58.8%) had a sponge cervix (P value = 0.046, 0.036, 0.006). Also, 34 (66.66%) patients needed hysterectomy. The diameter, length, and surface of the largest lacunae limited to women with hysterectomy were 12.00 (5-24) mm, 18.00 (11-56) mm, 231.00 (60-1176) mm2, and they were 9.00 (5-18) mm, 15.00 (10-28) mm, and 136.00(50-504) mm2 for women without hysterectomy (P value = 0.012, 0.070, 0.021). 24(70.6%) women with hysterectomy had Jellyfish signs, 29 (85.3%) of them had bulging on the cervix, and 15 (44.1%) had sponge cervix (P value = 0.05, 0.036, 0.028). The cut-off associated with the Lacunar surface was 163.5 mm2. Its sensitivity was 80%, and its specificity was 48% (P value = 0.021). CONCLUSION: The presence of single large lacunae could be a suitable predictive factor for bleeding in the placenta accreta spectrum; Moreover, there are some other US criteria, including the presence of a sponge cervix or the Jellyfish sign that are valuable predictive factors for negative outcomes for this spectrum, including hysterectomy.

Crucial factors for implementing treatment strategies in intractable atonic postpartum haemorrhage: early phase contrast medium extravasation on dynamic CT.

AIM: To identify the relationship between contrast medium extravasation (CME) on dynamic contrast-enhanced computed tomography (DCT) and clinical information in intractable atonic postpartum haemorrhage (PPH) and its relevance to treatment with uterine artery embolisation (UAE). MATERIALS AND METHODS: Of 90 patients who underwent DCT to diagnose PPH, 60 diagnosed with intractable atonic PPH were investigated retrospectively. Maternal background and clinical indicators were analysed to compare the positive and negative factors of early phase CME. Regression analysis was used to investigate the factors associated with CME. The sensitivity, specificity, and positive and negative predictive values of early phase CME for predicting UAE were calculated. Clinical outcomes were compared between the two groups according to the timing of the decision to undergo UAE. RESULTS: Of the 60 patients with intractable atonic PPH, 21 underwent UAE, 20 of whom had early phase CME on DCT. Pre-DCT clinical parameters and clinical indices were not significantly different in presence of early phase CME. Early phase CME was associated with UAE performance, with a sensitivity of 95%, specificity of 87%, positive predictive value of 80%, and negative predictive value of 97%. In cases where UAE was performed after conservative management, there was a significant increase in blood loss and transfusion volume. CONCLUSION: Early phase CME is not indicated by background factors or clinical findings. UAE is not required when CME cannot be detected in the uterine cavity. If early phase CME is present, UAE should be considered immediately.

Association between first-trimester ultrasound imaging of eccentric implantation and retained placenta.

OBJECTIVES: To evaluate first-trimester ultrasound imaging of eccentric implantation in predicting the probability of retained placenta. METHODS: A total of 61 cases with gestational sac eccentrically implanted in first-trimester ultrasound imaging was selected. Demographic and obstetric data were collected through data extraction of the electronic medical record at the time of delivery admission. Baseline characteristics (including age, gestational age of first-trimester ultrasound, size of gestational sac, gestational age of delivery), delivery outcomes (mode of delivery, retained placenta or placental fragments, blood loss, postpartum hemorrhage and postpartum ultrasound imaging) were collected and analyzed. RESULTS: The risk difference for a woman with eccentric implantation to have a retained placenta was -0.18 (95% CI -0.28 to -0.08, p = 0.000) and the incidence of retained placenta in the study group was higher than in the control group (18% vs. 0%, p = 0.006). First-trimester ultrasound imaging of eccentric implantation was also found to be an independent risk factor for the incidence of inhomogeneous mass in postpartum ultrasound imaging (27.9% vs. 10.8%, adjusted OR 0.19, 95% CI 0.05 to 0.79, p = 0.012). Though 2 cases in the study group suffered postpartum hemorrhage, the risk difference for a woman with eccentric implantation to suffer postpartum hemorrhage was -0.03 (95% CI -0.08 to -0.01, not significant) and eccentric implantation did not increase postpartum hemorrhage rates (3.3% vs. 0%, not significant). CONCLUSIONS: First-trimester ultrasound imaging of eccentric implantation was associated with an increased risk of retained placenta and inhomogeneous mass in postpartum ultrasound imaging.

Uterine artery embolization for postpartum hemorrhage with placenta accreta spectrum.

BACKGROUND: The reported success rate of uterine artery embolization (UAE) for postpartum hemorrhage (PPH) differs by the cause of bleeding; in some reports, UAE shows less successful results in patients with placenta accreta spectrum (PAS). PURPOSE: To evaluate the outcome of UAE for treating PPH associated with PAS. MATERIAL AND METHODS: From September 2011 to September 2021, 227 patients (mean age = 34.67±4.06 years; age range = 19-47 years) underwent UAE for managing intractable PPH. Patients were divided into two groups: those with PAS (n = 46) and those without PAS (n = 181). Delivery details, embolization details, and procedure-related outcomes were compared between the two groups. P values <0.05 were considered statistically significant. RESULTS: The technical success rate was 96.9% (n = 222) and the clinical success rate was 93.8% (n = 215). There were no significant differences in outcome of UAE between the two patient groups. The technical success rate was 95.7% (n = 44) in patients with PAS and 98.3% (n = 178) in patients without PAS (P = 0.267). The clinical success rate was 91.3% (n = 42) in patients with PAS and 95.6% (n = 173) in patients without PAS (P = 0.269). There were 24 cases of immediate complications, including pelvic pain (n = 20), urticaria (n = 3), and puncture site hematoma (n = 1). No major complication was reported. CONCLUSION: UAE is a safe and effective method to control intractable PPH for patients with or without PAS.

The role of ultrasound in the diagnosis and management of postpartum hemorrhage.

Postpartum hemorrhage (PPH) is the leading cause of death or severe morbidity for the mother after delivery. As a consequence healthcare staff working in the delivery room should be trained to perform a prompt diagnosis and adequate management of PPH. Uneventful outcome is induced correct identification of the underlying cause of hemorrhage. Ultrasound is a promising technique for the prompt diagnosis of PPH etiology. Indeed, it is easily available, with relatively low cost, not using ionizing radiation, and can be used in different settings including the labor room, the operating theater and at the bedside of an affected women. In order to be effective Obstetricians should have an adequate knowledge of postpartum ultrasonography. In this article, we will review the sonographic findings occurring in PPH, in the differential diagnosis of the underlying cause of hemorrhage, that include retained placenta, morbidly adherent placenta, rupture of the uterus uterine, vascular anomalies of the uterine arteries and uterine inversion. We will also provide an algorithm to manage PPH according to the ultrasonographic findings.

Effectiveness of transarterial embolisation for intractable postpartum haemorrhage in a disseminated intravascular coagulation state, despite emergency hysterectomy.

PURPOSE: We evaluated the effectiveness of transarterial embolization (TAE) for intractable postpartum hemorrhage in patients with disseminated intravascular coagulation (DIC) despite emergency hysterectomy. MATERIALS AND METHODS: We retrospectively assessed TAE performed after emergency hysterectomy in 15 patients between July 2008 and January 2022. Underlying condition, technical success, clinical success, angiographic findings, laboratory findings, pregnancy-modified DIC score (The International Society on Thrombosis and Haemostasis), blood transfusion, ICU (Intensive care unit) admission day, hospital day, in-hospital mortality, and long-term sequelae were evaluated. RESULTS: All patients were diagnosed with DIC before embolization, with a 43.9 mean DIC score. All patients showed positive angiographic findings for active bleeding. Thirty-eight bleeding arteries were confirmed. The remnant uterine artery (n=25) was the most common focus of persistent bleeding, followed by the cervicovaginal artery (n=6), pudendal artery (n=3), obturator artery (n=2), vesical artery (n=1), and unspecified artery from the internal iliac artery (n=1). Technical and clinical success rates were 100% (15/15) and 93.3% (14/15), respectively. Mean nadir hemoglobin (Hb) level before embolization was 4.9 g/dL. All patients underwent massive transfusion before embolization (mean 33.2 packs of RBC). Postoperatively, a smaller amount of blood was transfused than before the procedure (mean 10.6 packs of RBC). Mean nadir Hb level after embolization was 8.2 g/dL. There was one instance each of in-hospital death, hypoxic brain damage, and ischemic acute kidney injury. CONCLUSION: Despite hysterectomy for postpartum bleeding, there could be multiple residual or uncontrolled bleeding foci, especially in case of DIC, for which TAE could be an effective treatment.

Risk Factors Associated with Clinical Failure of Uterine Artery Embolization for Postpartum Hemorrhage.

PURPOSE: To identify risk factors for clinical failure of uterine artery embolization (UAE) for postpartum hemorrhage (PPH), with particular attention to the uterine artery diameter. MATERIALS AND METHODS: This retrospective study included 47 patients who underwent UAE for PPH between January 1, 2010, and January 31, 2021. Technical success was defined as the completion of embolization of the arteries thought to be the cause of the bleeding. Clinical success was defined as no recurrent bleeding or need for additional therapeutic interventions. Univariate and multivariate analyses were performed to examine the risk factors associated with clinical failure of UAE. RESULTS: Of the 47 patients, 6 had recurrent bleeding. Of the 6 patients, 4 underwent hysterectomy, and 2 underwent repeat embolization. The clinical success rate was 87.2% (41/47), with no major adverse events such as uterine infarction or death. In univariate analysis, there were slight differences in multiparity (P = .115) and placental abruption (P = .128) and a significant difference in the findings of a narrow uterine artery on digital subtraction angiography (DSA) (P = .005). In multivariate analysis, only a narrow uterine artery on DSA was a significant factor (odds ratio, 18.5; 95% confidence interval, 2.5-134.8; P = .004). CONCLUSIONS: A narrow uterine artery on DSA was a risk factor for clinically unsuccessful UAE for PPH. It may be prudent to conclude the procedure only after it is ensured that vasospasm has been relieved.

Interactions between ultrasonographic cervical length and placenta accreta spectrum on severe postpartum hemorrhage in women with placenta previa.

OBJECTIVE: To explore the interactions between cervical length (CL) and placenta accreta spectrum (PAS) on severe postpartum hemorrhage (SPPH) in patients with placenta previa. METHODS: A retrospective case-control study was conducted at four medical centers in China, and 588 patients with placenta previa were included. The logistic regression analysis and restricted cubic splines (RCS) were used to evaluate the association between CL and SPPH. Furthermore, the joint effect of CL and PAS on SPPH was assessed, and the additive and multiplicative interactions were calculated. RESULTS: After adjusting for potential confounders, the negative linear dose-response relationship was confirmed by RCS, and the change of odds ratio (OR) was more significant when CL was 2.5 cm or less. The risk of SPPH was significantly higher when CL of 2.5 cm or less co-existed with placenta increta/percreta than when CL of 2.5 cm less, or placenta increta/percreta existed alone (adjusted OR [aOR]CL ≤2.5cm&placenta accreta/non-PAS 3.40, 95% confidence interval [CI] 1.37-8.45; aORplacenta increta/percreta&CL >2.5cm 4.75, 95% CI 3.03-7.47; aORCL ≤2.5cm&placenta increta/percreta 14.51, 95% CI 6.08-34.64), and there might be additive interaction between CL and placenta increta/percreta on SPPH (attributable proportion due to interaction 50.7%, 95% CI 6.1%-95.3%). CONCLUSION: If CL was routinely performed during PAS evaluation, the increased OR of short CL and PAS could allow better patient preparation through counseling.

Assessment of postpartum haemorrhage for placenta accreta: Is measurement of myometrium thickness and dark intraplacental bands using MRI helpful?

BACKGROUND: This study aimed to investigate the predictive values of magnetic resonance imaging (MRI) myometrial thickness grading and dark intraplacental band (DIB) volumetry for blood loss in patients with placenta accreta spectrum (PAS). METHODS: Images and clinical data were acquired from patients who underwent placenta MRI examinations and were diagnosed with PAS from March 2015 to January 2021. Two radiologists jointly diagnosed, processed, and analysed the MR images of each patient. The analysis included MRI-based determination of placental attachment, as well as myometrial thickness grading and DIB volumetry. The patients included in the study were divided into three groups according to the estimated blood loss volume: in the general blood loss (GBL) group, the estimated blood loss volume was < 1000 ml; in the massive blood loss (MBL) group, the estimated blood loss volume was ≥ 1000 ml and < 2000 ml; and in the extremely massive blood loss (ex-MBL) group, the estimated blood loss volume was ≥ 2000 ml. The categorical, normally distributed, and non-normally distributed data were respectively analysed by the Chi-square, single-factor analysis of variance, and Kruskal-Wallis tests, respectively. The verification of correlation was completed by Spearman correlation analysis. The evaluation capabilities of indicators were assessed using receiver operating characteristic curves. RESULTS: Among 75 patients, 25 were included in the GBL group, 26 in the MBL group, and 24 in the ex-MBL group. A significant negative correlation was observed between the grade of myometrial thickness and the estimated blood loss (P < 0.001, ρ = - 0.604). There was a significant positive correlation between the volume of the DIB and the estimated blood loss (P < 0.001, ρ = 0.653). The areas under the receiver operating characteristic curve of the two MRI features for predicting blood loss ≥ 2000 ml were 0.776 and 0.897, respectively. CONCLUSIONS: The grading and volumetric MRI features, myometrial thickness, and volume of DIB, can be used as good prediction indicators of the risk of postpartum haemorrhage in patients with PAS.

Intraplacental T2-hypointense bands may help predict placental invasion depth and postpartum hemorrhage in placenta accrete spectrum disorders in high-risk gravid patients.

INTRODUCTION: Accurate noninvasive prenatal diagnosis of placenta accreta spectrum (PAS) disorder is critical for delivery management. PURPOSE: To evaluate the diagnostic ability of MRI features in predicting the PAS, invasive depth and postpartum hemorrhage (PPH) in high-risk gravid patients. MATERIALS AND METHODS: Between February 2019 and November 2020, women with ultrasound (US)-suspected PAS were enrolled. With the exclusion criteria, 80 women were included in the study. Two experienced genitourinary radiologists reviewed and recorded the MRI features. The chi square test was used to compare the effectiveness of MRI features. Relative risk ratios were computed to test the association of intraplacental T2-hypointense bands with poor outcomes of cesarean section. Receiver operating characteristic (ROC) analyses based on the number and area of intraplacental T2-hypointense bands were used to predict PAS, invasion depth, and PPH. RESULTS: PAS was diagnosed in 56 of 80 women (70%). At delivery, 24 of 80 women (30%) experienced PPH (≥1000 mL). Intraplacental T2-hypointense bands were detected at MRI in 28 of 56 women with PAS (50%). The relative risk ratio of intraplacental T2-hypointense bands was 1.51 for PAS, 3.17 for depth of PAS invasiveness and 4.74 for PPH. The largest areas of intraplacental T2-hypointense bands for predicting PAS, invasion depth and PPH were 0.66 cm2, 1.68 cm2 and 1.99 cm2, respectively. DISCUSSION: The appearance of intraplacental T2-hypointense bands has important diagnostic value for PAS, its invasion depth and PPH. The area of the largest T2-hypointense band in the placenta can predict poor outcomes of cesarean section.

The MRI estimations of placental thickness and cervical length correlate with postpartum hemorrhage (PPH) in patients with risk for placenta accreta spectrum (PAS) disorders.

INTRODUCTION: This study aims to identify whether placental thickness and cervical length measured by MRI correlate with postpartum hemorrhage (PPH) in patients at high risk for placenta accreta spectrum (PAS) disorders. METHODS: The placental thickness and cervical length of 200 patients from October 2017 to October 2021 were retrospectively measured. The mid-sagittal plane of the placentas was measured by 2 independent radiologists using MRI. Partial correlation analysis was used to characterize the correlation between placental thickness, cervical length and estimated blood loss during surgery. The correlation between clinical features, placental thickness, cervical length and PPH was evaluated with univariate and multivariate analyses. A nomogram was constructed based on the logistic regression. RESULTS: Placental thickness was positively correlated with the estimated blood loss during delivery, while cervical length had a negative correlation with it, based on the adjustment for gestational age. Multivariate analyses revealed that prior cesarean section, placenta previa, increased placental thickness(≧4.35 cm) and short cervical length（< 3.05 cm） were independent risk factors for PPH. When the 4 risk factors were combined together, the AUC was the highest, 0.773 (95%CI 0.707-0.840). DISCUSSION: Placental thickness and cervical length correlated with PPH. The nomogram constructed based on prior cesarean section, placenta previa, placental thickness and cervical length can be used to recognize patients with a higher risk of PPH.

Recurrent postpartum hemorrhage at subsequent pregnancy in patients with prior uterine artery embolization: angiographic findings and outcomes of repeat embolization.

OBJECTIVE: To evaluate angiographic findings and outcomes of uterine artery embolization (UAE) for recurrent postpartum hemorrhage (PPH) in a subsequent pregnancy in patients with a history of prior UAE. METHODS: Between March 2004 and February 2021, UAE was performed for PPH with gelatin sponge slurry in 753 patients. Among these, 13 underwent repeat UAE for recurrent PPH after subsequent delivery. The causes of PPH, angiographic findings, hemostasis, and adverse events were evaluated. RESULTS: The causes of recurrent PPH included retained placental tissue (n = 9) and uterine atony (n = 4). On angiography, unilateral or bilateral uterine arteries were obliterated due to prior UAE in 10 patients (76.9%). The uterine collateral vessels were embolized (anterior division of the internal iliac artery [n = 10], round ligament [n = 5], and ovarian [n = 4] artery). In the remaining three patients with recanalized or patent (not embolized at prior UAE) uterine arteries, both uterine arteries were embolized. Immediate hemostasis was achieved in nine patients (69.2%). The remaining four patients (30.8%) with obliterated uterine arteries required hysterectomy. There were three mild adverse events (pelvic pain [n = 2] and fever [n = 1]). CONCLUSION: UAE with gelatin sponge slurry frequently causes permanent uterine artery obliteration. In cases of recurrent PPH occurring in subsequent pregnancy, repeat UAE may be less likely to achieve hemostasis (69.2%). ADVANCES IN KNOWLEDGE: 1. UAE with gelatin sponge slurry frequently caused permanent uterine artery obliteration.2. In recurrent PPH occurring in subsequent pregnancy, the repeat UAE may be less likely to achieve hemostasis than initial UAE.