Placenta Accreta Spectrum

Usefulness of decision tree analysis of MRI features for diagnosis of placenta accreta spectrum in cases with placenta previa

PURPOSE

Placenta previa complicated by placenta accrete spectrum (PAS) is a life-threatening obstetrical condition; therefore, preoperative diagnosis of PAS is important to determine adequate management. Although several MRI features that suggest PAS has been reported, the diagnostic importance, as well as optimal use of each feature has not been fully evaluated.

MATERIALS AND METHODS

The occurrence of 11 PAS-related MRI features was investigated in MR images of 145 patients with placenta previa. The correlation between each MRI feature and pathological diagnosis of PAS was evaluated using univariate analysis. A decision tree model was constructed according to a random forest machine learning model of variable selection.

RESULTS

Eight MRI features showed a significant correlation with PAS in univariate analysis. Among these features, placental/uterine bulge and myometrial thinning showed high odds ratios: 138.2 (95% CI: 12.7-1425.6) and 66.0 (95% CI: 18.01-237.1), respectively. A decision tree was constructed based on five selected MRI features: myometrial thinning, placental bulge, serosal hypervascularity, placental ischemic infarction/recess, and intraplacental T2 dark bands. The decision tree predicted the presence of PAS in the randomly assigned validation cohort with significance (p < 0.001). The sensitivity and the specificity of the decision tree for detecting PAS were 90.0% (95%CI: 53.2-98.9) and 95.5% (95%CI: 89.9-96.8), respectively.

CONCLUSION

Among PAS-related MRI features, placental/uterine bulge and myometrial thinning showed high diagnostic values. In addition, the present decision tree model was shown to be effective in predicting the presence of PAS in cases with placenta previa.

Nationwide Assessment of Gestational Age Distribution at Delivery for Patients With Placenta Accreta Spectrum Disorder

OBJECTIVE

To assess the distribution of gestational age at delivery for patients with placenta accreta spectrum (PAS) in the United States.

METHODS

This serial cross-sectional study examined 26,375 hospital deliveries with a diagnosis code for PAS identified in the Agency for Healthcare Research and Quality's Healthcare Cost and Utilization Project National Inpatient Sample from 2016 to 2021. Descriptive analysis was performed to evaluate the distribution of gestational age at delivery of patients with PAS and related obstetric characteristics. The incidence of PAS codes was also assessed among 21,212,493 hospital deliveries.

RESULTS

The majority of patients with PAS delivered preterm (before 37 weeks of gestation, 56.9%); 43.1% delivered at term (37 weeks of gestation or more). Compared with patients with PAS who had preterm deliveries, those with PAS who had term deliveries were more likely to deliver vaginally (32.0% vs 6.9%) and in a rural-setting (9.7% vs 2.3%) or small-bed-capacity (18.6% vs 8.4%) hospital and were less likely to have placenta previa (9.3% vs 50.5%) and increta and percreta subtypes (8.6% vs 27.4%) (all P<.001). Incidences of hemorrhage or blood transfusion or both (62.9% vs 71.5%), shock or coagulopathy or both (6.2% vs 9.8%), hysterectomy (25.6% vs 65.3%), urinary tract injury (2.5% vs 10.0%), and maternal mortality (0.0% vs 0.2%) were lower for patients with PAS who had term compared with preterm deliveries (all P<.001). When any hospital deliveries were included in the analysis, 1 in every 804 delivering patients had a diagnosis of PAS. The incidence sharply decreased from 1 in 83-300 hospital deliveries in the preterm period to 1 in 705-3,037 hospital deliveries after 37 weeks of gestation. The incidence of PAS increased by 15.4% (95% CI, 10.7-20.4), from 114.8 to 132.5 per 100,000 hospital deliveries during the 6-year study period (P trend<.001).

CONCLUSION

In this nationwide, cross-sectional study in the United States, nearly 40% of patients with PAS delivered at term and had distinct clinical and obstetric characteristics and outcomes compared with patients with PAS who delivered preterm. Continued increase in the incidence of PAS at the national level calls for attention and evaluation.

Radiomics analysis of placental MRI for prenatal prediction of placenta accreta spectrum in pregnant women in the third trimester: A retrospective study of 594 patients

OBJECTIVE

To develop and validate a model based on placental MRI for the prenatal prediction of placenta accreta spectrum (PAS) in pregnant women in the third trimester.

MATERIALS AND METHODS

A total of 594 pregnant women who were suspected of having PAS and underwent placental MRI antenatally were included and were allocated into the training cohort and testing cohort at a 2:1 ratio. MRI diagnosis was determined by three experienced radiologists. Radiomic features were extracted from images of T2 weighted imaging for each patient. After a feature selection strategy, a radiomics signature and a clinical-radiomics nomogram combining radiomics score and clinical risk factors were constructed to predict PAS. The performance of each model was evaluated using the area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, specificity, and clinical utility.

RESULTS

MRI diagnosis yielded AUCs of 0.77 and 0.79 for predicting PAS in the training and testing cohorts, respectively. The AUCs of the radiomics signature used to predict PAS in both cohorts were 0.80 and 0.83, respectively. The nomogram accurately predicted PAS in both cohorts (AUC = 0.84 and 0.89), with better results than those of MRI diagnosis and radiomics signature in the training (p = 0.009 and 0.003, respectively) and testing cohorts (p = 0.010 and 0.008, respectively), decision curve analysis confirmed its best clinical utility compared to the other models.

CONCLUSION

Radiomics analysis based on placental MRI may serve as an effective tool to predict PAS in patients with possible PAS in the third trimester.

Caffeic acid stimulates migration and invasion of human trophoblast HTR-8/SVneo cells

The placenta is a transient organ essential for development of the fetus. Adequate invasion of trophoblast cells, specialized cells of the placenta, is of utmost importance for the establishment and maintenance of healthy pregnancy. Caffeic acid (CA), one of the most abundantly present hydroxycynamic acids in everyday human diet, exhibits various physiological effects such as antioxidant, anti-inflammatory and anticancer activities including an inhibitory effect on migration and invasion of different cancer cell types. There are not many studies on CA safety in human pregnancy. Therefore, the aim of this research was to investigate the potential of CA to affect trophoblast cell function. We evaluated adhesion, migration and invasion of human trophoblast HTR-8/SVneo cells following CA treatment by functional assays. Furthermore, expression of molecular mediators of these processes such as integrin α1, α5 and β1 subunits and matrix metalloproteinase (MMP)-2 and MMP-9 was evaluated at the mRNA level by qPCR and the protein level by cell-based ELISA assay or zymography. Our results showed that 24 h treatment with 10 μM CA stimulated migration and invasion of HTR-8/SVneo cells as well as expression of the integrin α1 subunit. Furthermore, treatment with 100 μM CA stimulated expression of MMP2 and MMP9 mRNA in the treated HTR-8/SVneo cells as well as secretion of MMP-9. According to obtained results, we can conclude that CA could have the potential to affect processes important for placentation. However, further research is needed to elucidate all aspects of potential CA effects on placental function and pregnancy as a whole.

Research design and tissue collection considerations for investigation of placenta accreta spectrum

Placenta accreta spectrum (PAS) is a group of pregnancy pathologies characterized by loss/absence of decidua and trophoblast over-invasion penetrating into the myometrium beyond the normal depth. It is associated with expansion of deeper branches of the uterine arteries and placental adherence to the uterus. Undetected PAS leads frequently to massive and potentially fatal hemorrhage at delivery. For the more severe forms of PAS (increta, percreta), the most frequent solution is caesarean delivery-hysterectomy. The etiology of PAS is, however, unclear at best. While there is increasing research interest, the clinical intricacies of this pathology pose significant challenges for the researcher. In this communication we present the elements which we believe should be considered when undertaking (or interpreting) research into PAS, particularly when biological samples and molecular techniques are involved.

Machine Learning for the Prediction of Surgical Morbidity in Placenta Accreta Spectrum

OBJECTIVE

 We sought to create a machine learning (ML) model to identify variables that would aid in the prediction of surgical morbidity in cases of placenta accreta spectrum (PAS).

STUDY DESIGN

 A multicenter analysis including all cases of PAS identified by pathology specimen confirmation, across five tertiary care perinatal centers in New York City from 2013 to 2022. We developed models to predict operative morbidity using 213 variables including demographics, obstetrical information, and limited prenatal imaging findings detailing placental location. Our primary outcome was prediction of a surgical morbidity composite defined as including any of the following: blood loss (>1,500 mL), transfusion, intensive care unit admission, vasopressor use, mechanical ventilation/intubation, and organ injury. A nested, stratified, cross-validation approach was used to tune model hyperparameters and estimate generalizability. Gradient boosted tree classifier models incorporated preprocessing steps of standard scaling for numerical variables and one-hot encoding for categorical variables. Model performance was evaluated using area under the receiver operating characteristic curve (AUC), positive and negative predictive values (PPV, NPV), and F1 score. Variable importance ranking was also determined.

RESULTS

 Among 401 PAS cases, 326 (81%) underwent hysterectomy. Of the 401 cases of PAS, 309 (77%) had at least one event defined as surgical morbidity. Our predictive model had an AUC of 0.79 (95% confidence interval: 0.69, 0.89), PPV 0.79, NPV 0.76, and F1 score of 0.88. The variables most predictive of surgical morbidity were completion of a hysterectomy, prepregnancy body mass index (BMI), absence of a second trimester ultrasound, socioeconomic status zip code, BMI at delivery, number of prenatal visits, and delivery time of day.

CONCLUSION

 By identifying social and obstetrical characteristics that increase patients' risk, ML models are useful in predicting PAS-related surgical morbidity. Utilizing ML could serve as a foundation for risk and complexity stratification in cases of PAS to optimize surgical planning.

KEY POINTS

· ML models are useful models are useful in predicting PAS-related surgical morbidity.. · Optimal management for PAS remains unclear.. · Utilizing ML can serve as a foundation for risk and complexity stratification in cases of PAS..

Preoperative ultrasound risk factors for peripartum hysterectomy among PAS suspected pregnancies

OBJECTIVE

This study aimed to identify risk factors for peripartum hysterectomy among pregnancies complicated by suspected Placenta Accreta Spectrum (PAS) in preoperative obstetric imaging screening.

METHODS

Data were retrospectively extracted from the Longitudinal Placenta Accreta Spectrum Study (LoPASS), covering pregnancies with PAS from January 2018 to March 2023 at our institute. Patients were divided into Control and Hysterectomy groups based on whether they underwent hysterectomy. Sociodemographic, obstetric, and clinical characteristics were compared between the groups. Multivariate logistic regression analysis was performed on the characteristics with statistical significance to explore risk factors for peripartum hysterectomy.

RESULTS

Among 523 pregnancies with suspected PAS, 20 underwent hysterectomy. The Hysterectomy group had a significantly higher mean age (34.50 ± 5.05 vs. 31.66 ± 4.43 years, p = 0.005) and pre-pregnancy BMI (26.35 ± 3.27 vs. 23.84 ± 3.99, p = 0.006). The Hysterectomy group also had a higher proportion of patients with more than 2 gravidities (100% vs. 61.6%, p = 0.022) and multiple parities (90.0% vs. 39.9%, p < 0.001). Higher percentages of placenta percreta (90.0% vs. 28.2%, p < 0.001), placenta attaching to the anterior uterine wall (57.9% vs. 31.8%, p = 0.033), and higher PAS ultrasonographic scores (11.78 ± 2.68 vs. 6.79 ± 2.77, p < 0.001) were observed in the Hysterectomy group. Perioperative outcomes revealed significantly longer surgical durations (171.90 ± 49.27 vs. 53.46 ± 24.41 min, p < 0.001) and higher rates of preterm birth (100.0% vs. 55.3%, p < 0.001). Intraoperative blood loss was also substantially greater in the Hysterectomy group (2695.00 ± 1241.17 ml vs. 764.31 ± 385.10 ml, p < 0.001). Variables significantly associated with increased peripartum hysterectomy risk included prior cesarean sections (OR = 1.44, p = 0.048), placenta attaching to the anterior uterine wall (OR = 0.73, p = 0.015), placenta completely covering the uterine incision (OR = 1.27, p = 0.035), gestational hypertensive disorder (OR = 1.69, p = 0.042), placenta percreta (OR = 2.31, p = 0.032), and PAS ultrasonographic score higher than 10 (OR = 2.71, p = 0.008).

CONCLUSION

Most of ultrasound PAS scoring subitems were significantly higher in Hysterectomy group. Cesarean deliveries, placental positioning on the anterior uterine wall, GHD, types of PAS, and ultrasound PAS score higher than 10 predicts peripartum hysterectomy, highlighting the importance of early, timely, and consistent monitoring of the placenta using obstetric ultrasound in pregnancies with suspected PAS.

TRIAL REGISTRATION

ChiCTR2100052428, October 26th, 2021.

Lower level of miR-34a leads to placenta accreta spectrum by promoting the proliferation, migration of trophoblast villous epithelial cells and enhanced the angiogenesis of vascular endothelial cells

INTRODUCTION

The overall prevalence of placenta accreta spectrum (PAS) is approximately 0.17 %, but it accounts for 7 % of maternal mortality and is associated with intraoperative and postoperative morbidity. The pathogenesis mechanisms of PAS include an imbalance between decidualization and trophoblast invasion. The aim of this study is to identify the pathogenesis roles of miR-34a in PAS.

METHODS

For this purpose, we collected 15 placenta tissues from pregnant subjects with PAS complications and another 15 placenta tissues from normal pregnancy (NP) cases. Then, we conducted in situ hybridization assay to compare miR-34a expression level, followed by in vitro simulations of NP and PAS with miR-34a and scrambled control (SC) mimic transfection in cells, respectively. Next, we conducted in vitro cellular assays to investigate the pathogenesis mechanisms of miR-34a in PAS.

RESULTS

We first confirmed significantly lower level of miR-34a in the trophoblast villous (TV) from PAS patients. By in vitro assays, lower miR-34a led to significantly higher cell proliferation and enhanced cell migration in TV epithelial cells. In addition, lower miR-34a resulted in elevated angiogenesis ability in vascular endothelial cells. Finally, to identify the pathway involved by miR-34a in PAS, we used microarray (raw data available via NCBI GEO database with accession number GSE279257) and flow cytometry to confirm that lower miR-34a significantly repressed the apoptosis activity in TV epithelial cells.

DISCUSSION

In this study, we not only confirmed miR-34a as a biomarker of PAS but also clarified the in vitro pathogenesis mechanism of miR-34a in PAS.

Pregnancy Outcomes after Uterine Preservation Surgery for Placenta Accreta Spectrum: A Retrospective Cohort Study

OBJECTIVE

 This study aimed to investigate maternal and neonatal outcomes in subsequent pregnancies of women with a history of placenta accreta spectrum (PAS) compared with women without history of PAS.

STUDY DESIGN

 A retrospective cohort study conducted at a single tertiary center between March 2011 and January 2022. We compared women with a history of PAS who had uterine preservation surgery and a subsequent pregnancy, to a control group matched in a 1:5 ratio. The primary outcome was the occurrence of a composite adverse outcome (CAO) including any of the following: uterine dehiscence, uterine rupture, blood transfusion, hysterectomy, neonatal intensive care unit admission, and neonatal mechanical ventilation. Multivariable logistic regression was performed to evaluate associations with the CAO.

RESULTS

 During the study period, 287 (1.1%) women were diagnosed with PAS and delivered after 25 weeks of gestation. Of these, 32 (11.1%) women had a subsequent pregnancy that reached viability. These 32 women were matched to 139 controls. There were no significant differences in the baseline characteristics between the study and control groups. Compared with controls, the proportion of CAO was significantly higher in women with previous PAS pregnancy (40.6 vs. 19.4%, p = 0.019). In a multivariable logistic regression analysis, previous PAS (adjusted odds ratio [aOR] = 3.31, 95% confidence interval [CI] = 1.09-10.02, p = 0.034) and earlier gestational age at delivery (aOR = 3.53, 95% CI = 2.27-5.49, p < 0.001) were independently associated with CAOs.

CONCLUSION

 A history of PAS in a previous pregnancy is associated with increased risk of CAOs in subsequent pregnancies.

KEY POINTS

· The uterine-preserving approach for PAS delivery is gaining more attention and popularity in recent years.. · Women with a previous pregnancy with PAS had higher rates of CAOs in subsequent pregnancies.. · Previous PAS pregnancy is an independent factor associated with adverse outcomes..

Intrauterine adhesions treated with hysteroscopic adhesiolysis and subsequent obstetric outcome: A retrospective matched cohort study

OBJECTIVE

To examine whether a history of hysteroscopic adhesiolysis (HA)-treated intrauterine adhesions (IUAs) was associated with an increased risk of adverse obstetrical outcomes in subsequent pregnancies.

DESIGN

Retrospective cohort study.

SETTING

A tertiary-care hospital in Shanghai, China.

POPULATION

A cohort of 114 142 pregnant women who were issued an antenatal card and received routine antenatal care in Shanghai First Maternity and Infant Hospital, between January 2016 and October 2021.

METHODS

From the cohort of 114 142 pregnant women, each woman with a history of HA-treated IUA prior to the current pregnancy (n = 780) was matched with four women without a history of IUAs (n = 3010) using propensity score matching. The matching variables were maternal age and parity, mode of conception, pre-pregnancy body mass index and prior history of abortion.

MAIN OUTCOME MEASURES

Pregnancy complications, placental abnormalities, postpartum haemorrhage and adverse birth outcomes.

RESULTS

Compared with women with no history of IUAs, women with a history of HA-treated IUAs were at higher risk of pre-eclampsia (RR 1.69, 95% CI 1.23-2.33), placenta accreta spectrum (RR 4.72, 95% CI 3.9-5.73), placenta praevia (RR 4.23, 95% CI 2.85-6.30), postpartum haemorrhage (RR 2.86, 95% CI 1.94-4.23), preterm premature rupture of membranes (RR 3.02, 95% CI 1.97-4.64) and iatrogenic preterm birth (RR 2.86, 95% CI 2.14-3.81). Those women were also more likely to receive cervical cerclage (RR 5.63, 95% CI 3.95-8.02) during pregnancy and haemostatic therapies after delivery (RR 2.17, 95% CI 1.75-2.69). Moreover, we observed that the RRs of those adverse obstetrical outcomes increased with the increasing number of hysteroscopic surgeries.

CONCLUSIONS

This study found that a history of HA-treated IUAs, especially a history of repeated HAs, was associated with an increased risk of adverse obstetrical outcomes.

Beyond the Scalpel: Unravelling the Anaesthetic Maze in Elective C-Section for Placenta Accreta Spectrum

Placenta accreta spectrum (PAS) disorders pose significant challenges in the anaesthetic management of elective caesarean section. This article explores the anaesthetic considerations for patients with PAS focusing on the optimal techniques to ensure maternal safety and surgical success. The analysis examines the advantages and disadvantages of general anaesthesia, neuraxial anaesthesia, and combined techniques to inform considerations of anaesthetic management in this high-risk population.

Surgical Morbidity following Planned Hysterectomy versus Conservative Management for Placenta Accreta Spectrum: A Systematic Review and Meta-analysis

OBJECTIVE

 In recent years, the management of placenta accreta spectrum (PAS) has fallen into two categories: planned hysterectomy and conservative management to preserve fertility. However, optimal management remains unclear. Therefore, we conducted a systematic review and meta-analysis comparing the two to evaluate which approach was associated with lower surgical morbidity.

STUDY DESIGN

 MEDLINE, Scopus, Cochrane Library, and ClinicalTrials.gov were searched from inception to July 31, 2023, for trials comparing conservative management versus planned hysterectomy. We included all prospective or retrospective cohort studies, case-control studies, and randomized control studies that reported outcomes related to surgical morbidity in cases of PAS. Surgical morbidity was defined as rates of intensive care unit (ICU) admission, disseminated intravascular coagulation (DIC)/coagulopathy, bladder injury, number of units of packed red blood cells (PRBCs) transfused, estimated blood loss (EBL), and maternal mortality.

RESULTS

 Odds ratios (ORs) were computed with 95% confidence intervals (CIs) using a fixed or random effects model. Among 839 studies initially retrieved, 12 were included with a total of 1,167 patients. Of these, 669 (57.3%) underwent conservative management and 498 (42.7%) underwent a planned hysterectomy. Conservative management resulted in lower rates of ICU admission (OR = 0.11; 95% CI: 0.04, 0.35), lower rates of bladder injury (OR = 0.31; 95% CI: 0.2, 0.48), lower incidence of DIC or coagulopathy (OR = 0.22; 95% CI: 0.10, 0.48), lower mean difference EBL (-1,292.81 mL; 95% CI: -1,922.16 to -593.46), as well as lower number of PRBC units transfused (-1.54 units; 95% CI: -2.29 to -0.78).

CONCLUSION

 Our findings suggest that conservative management of PAS may be associated with reduced surgical morbidity.

KEY POINTS

· management of PAS has fallen into two categories: planned hysterectomy and conservative management.. · Optimal management for PAS remains unclear.. · conservative management of PAS may be associated with reduced surgical morbidity..

Prenatal ultrasound scoring in diagnosis and postpartum outcomes prediction for Placenta Accreta Spectrum (PAS): a systematic review

BACKGROUND

Placenta accreta spectrum (PAS) is one of the most dangerous pregnancy-related conditions. This study aims to conduct a systematic review of current research on the ultrasound scoring systems used in PAS patients with a comprehensive summarization of researches and comparison of prenatal ultrasound scoring in evaluating postpartum outcomes.

METHODS

This systematic review was conducted and reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies were retrieved from four databases (PubMed, Cochrane Library, Embase and Web of Science) up to December 2023. Original studies involving women diagnosed with PAS using ultrasound scoring for diagnosis or outcome evaluation were screened based on predefined inclusion and exclusion criteria. The primary outcome was the diagnostic performance of ultrasound scoring systems and their effectiveness in predicting labor outcomes. The Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was utilized to assess the study quality. The study has been registered on the PROSPERO website with the registration number CRD42024507311.

RESULTS

Sixteen studies met the inclusion criteria. 3930 patients were included in the review, with 1693 participants in the control group. Included studies had a high risk of bias in patient selection, with a low risk in flow and timing and reference standards. Existing studies have reported several indicators that can be included in ultrasound scoring systems and tested their effectiveness in diagnosis and severity evaluation. The pool sensitivity, specificity, and area under the curve (AUC) of ultrasound scoring system in diagnosing PAS were 0.89 (95% confidence interval [CI]: 0.82-0.94), 0.85(95%CI: 0.80-0.90) and 0.93 (95%CI:0.91-0.95). Ultrasound scores are associated with PAS outcomes including intraoperative haemorrhage, postpartum haemorrhage, hysterectomy, length of hospital stay, and neonatal prognosis. Limitation is that the existing studies are wide-ranging but have low replication and association.

CONCLUSION

Ultrasound scoring systems play a role in the prenatal diagnosis, management, and prediction of postnatal complications in PAS. Nevertheless, additional research is required to further evaluate the performance between different scoring systems to develop a unified consensus.

Anesthetic Considerations and Blood Utilization for Placenta Accreta Spectrum

The anesthetic management of the patient with placenta accreta spectrum begins before surgery by assessing the patient and their comorbidities and providing psychological preparation for the perioperative period. Choosing neuraxial or general anesthesia for surgery balances the procedure's clinical needs with the patient's desires. Intraoperatively, management of homeostasis during acute blood loss requires assessments of central volume to avoid over-transfusion. Viscoelastic testing may be useful to assess coagulation to target the replacement of coagulation factors. Postoperative care is an essential continuum of the procedure, and the availability of bedside ultrasound can aid rapid decision-making.

PAS or Not PAS? The Sonographic Assessment of Placenta Accreta Spectrum Disorders and the Clinical Validation of a New Diagnostic and Prognostic Scoring System

This study aimed to evaluate our center's experience in diagnosing and managing placenta accreta spectrum (PAS) in a high-risk population, focusing on prenatal ultrasound features associated with PAS severity and maternal outcomes. We conducted a retrospective analysis of 102 high-risk patients with confirmed placenta previa who delivered at our center between 2018 and 2023. Patients underwent transabdominal and transvaginal ultrasound scans, assessing typical sonographic features. Binary and multivariate logistic regression analyses were performed to identify sonographic markers predictive of PAS and relative complications. Key ultrasound features-retroplacental myometrial thinning (<1 mm), vascular lacunae, and retroplacental vascularization-were significantly associated with PAS and a higher risk of surgical complications. An exceedingly rare sign, the "riddled cervix" sign, was observed in only three patients with extensive cervical or parametrial involvement. Those patients had the worst surgical outcomes. This study highlights the utility of specific ultrasound features in stratifying PAS risk and guiding clinical and surgical management in high-risk pregnancies. The findings support integrating these markers into prenatal diagnostic protocols to improve patient outcomes and inform surgical planning.

Evaluation of maternal serum protein biomarkers in the prenatal evaluation of placenta accreta spectrum: A systematic scoping review

INTRODUCTION

Placenta accreta spectrum (PAS) is an increasingly commonly reported condition due to the continuous increase in the rate of cesarean deliveries (CD) worldwide; however, the prenatal screening for pregnant patients at risk of PAS at birth remains limited, in particular when imaging expertise is not available.

MATERIAL AND METHODS

Two major electronic databases (MEDLINE and Embase) were searched electronically for articles published in English between October 1992 and January 2023 using combinations of the relevant medical subject heading terms and keywords. Two independent reviewers selected observational studies that provided data on one or more measurement of maternal blood-specific biomarker(s) during pregnancies with PAS at birth. PRISMA Extension for Scoping Review (PRISMA-ScR) was used to extract data and report results.

RESULTS

Of the 441 reviewed articles, 29 met the inclusion criteria reporting on 34 different biomarkers. 14 studies were retrospective and 15 prospective overall including 18 251 participants. Six studies had a cohort design and the remaining a case-control design. Wide clinical heterogeneity was found in the included studies. In eight studies, the samples were obtained in the first trimester; in five, the samples were collected on hospital admission for delivery; and in the rest, the samples were collected during the second and/or third trimester.

CONCLUSIONS

Measurements of serum biomarkers, some of which have been or are still used in screening for other pregnancy complications, could contribute to the prenatal evaluation of patients at risk of PAS at delivery; however, important evidence gaps were identified for suitable cutoffs for most biomarkers, variability of gestational age at sampling and the potential overlap of the marker values with other placental-related complications of pregnancy.

Abnormal placental development induced by repeated cesarean sections: Investigating an animal model of placenta accreta spectrum disorders

INTRODUCTION

Placenta accreta spectrum (PAS) is a serious condition associated with severe postpartum hemorrhage, leading to emergency hysterectomy. Research has predominantly focused on clinical diagnosis and the prevention of adverse maternal outcomes, but the underlying pathological mechanisms remain poorly understood, partly due to the limitations of animal models.

METHODS

In this study, we conducted up to three cesarean sections (CS) on full-term pregnant mice, since a history of multiple CS is an independent risk factor for PAS. We evaluated pregnancy outcomes, placental development, morphology, trophoblast invasion, and angiogenesis at the maternal-fetal interface to assess the impact of repeated CS.

RESULTS

Following repeated CS, the model mice displayed adverse pregnancy outcomes, including placental dysplasia, incomplete remodeling of spiral arteries, deep trophoblast invasion at the maternal-fetal interface, and reduced placental perfusion. Additionally, the mice exhibited abnormal fetal development, imbalances in angiogenic and anti-angiogenic both within the placenta and in peripheral blood.

CONCLUSION

The pathological phenotypes of placenta and adverse pregnancy outcomes observed in mice with a history of three CSs closely resemble the clinical features of PAS. This model offers a valuable tool for studying the pathogenesis of PAS and could serve as a foundation for the development of early prevention strategies.

Transcriptomic analysis identified novel biomarker in invasive placenta accreta spectrum

INTRODUCTION

Placenta accreta spectrum (PAS) disorders pose a grave threat to maternal life due to severe hemorrhage and the heightened risk of peripartum hysterectomy. Consequently, there's a pressing need for circulating biomarkers in clinical settings. MicroRNAs (miRNAs), being stable in peripheral circulation, hold promise as potential biomarkers for PAS.

METHODS

This study recruited singleton live pregnancies, including cases of invasive PAS, placenta previa (PP), and controls, across three phases. Initially, RNA-seq of peripheral blood identified 6 miRNAs in the screening phase. Subsequently, in the training and validation phases, miR-23a-5p, along with its target genes ASF1B and CHTF8, were validated using qRT-PCR. The diagnostic value of these markers for PAS and adverse outcomes was evaluated using Receiver Operating Characteristic (ROC) curves.

RESULTS

The results showed miR-23a-5p was down-regulated in PAS, whereas ASF1B and CHTF8 were up-regulated. miR-23a-5p had modest diagnostic efficiency for PAS and adverse outcomes, as the AUC were 0.689 and 0.711 respectively. However, when miR-23a-5p combined with CHTF8, the AUC can improve greatly to 0.869 in PAS diagnosis and 0.856 in prediction of adverse outcomes.

DISCUSSION

We propose the miR-23a-5p plays a role in PAS pathogenesis through regulating cell proliferation, migration, invasion, apoptosis by targeting various genes. This study confirmed its potential value of miR-23a-5p combined with target gene CHTF8 as novel biomarkers for PAS and adverse outcomes.

Uterine window and placenta accreta spectrum in a dichorionic, diamniotic twin gestation complicated by postpartum hemorrhage

Cesarean scar defects encompass a spectrum of separation of the uterine layers that increase risk of uterine rupture during labor and delivery. When coupled with the presence of placenta accreta spectrum, a condition characterized by abnormal adherence to or invasion of the myometrium by the placenta, the risk of life-threatening hemorrhage significantly increases. As rates of cesarean delivery increase, it is important to understand the imaging findings typical of both conditions. We present the case of a 30-year-old patient with a dichorionic, diamniotic twin gestation complicated by uterine window and placenta accreta spectrum.

Development and validation of a nomogram for predicting placenta accreta spectrum in pregnancies with one previous cesarean delivery

OBJECTIVE

This study aimed to develop and validate a prenatal nomogram to predict the risk of placenta accreta spectrum (PAS) in women with one previous cesarean delivery.

METHODS

This retrospective study enrolled 5157 pregnant women with one previous cesarean delivery in China from January 2021 to January 2023. The nomogram was developed from a training cohort of 3612 pregnant women and tested on a validation cohort of 1545 pregnant women. Multivariate regression analysis was performed using the minimum value of the Akaike information criterion to select prognostic factors that can be included in the nomogram. We evaluated the nomogram by the area under the receiver operating characteristic (ROC) curve, calibration curves, and the decision curve analysis (DCA).

RESULTS

PAS occurred in 199 (5.51%) and 80 (5.18%) patients in the training and validation cohorts, respectively. Backward stepwise algorithms in the multivariable logistic regression model determined abortion, hypertensive disorders complicating pregnancy, fetal position, and placenta previa as relevant PAS predictors. The area under the ROC curve for the nomogram was 0.770 (95% confidence interval [CI] 0.733-0.807) and 0.791 (95% CI 0.730-0.853) for the training and validation cohorts, respectively. The calibration curves indicated that the nomogram's prediction probability was consistent with the actual probability. The DCA curve revealed that the nomogram has potential clinical benefit.

CONCLUSION

A prenatal nomogram was developed for PAS in our study, which helped obstetricians determine potential patients with PAS and make sufficient preoperative preparation to reduce maternal and neonatal complications.

Conservative Management of Placenta Percreta With Perforation in an Infertile Lupus Patient Following Embryo Transfer: A Report of a Rare Case

Placenta accreta spectrum (PAS) is a life-threatening condition characterized by abnormal placental invasion of the myometrium and is often associated with uterine surgery. However, it can also occur in unscarred uteri, particularly during pregnancies using assisted reproductive technology (ART). Following a successful pregnancy via vitrified-warmed embryo transfer, a 33-year-old nulliparous woman with systemic lupus erythematosus and long-term steroid use presented with intra-abdominal hemorrhage due to placenta percreta and spontaneous uterine perforation at week 10 of gestation. The patient was managed conservatively to preserve fertility. Over two years, the placenta spontaneously resorbed, and laparoscopic repair of an anatomical defect in the muscular layer of the perforation was successfully performed. Finally, the uterus returned to normal size. This case underscores the increased risk of PAS in ART pregnancies, particularly during hormone replacement therapy cycles and long-term oral steroid administration, and highlights the potential for conservative management and fertility preservation following PAS with uterine perforation.

MR Evaluation of Placenta Accreta Spectrum: Concordance Rates and Effect of Structured Reporting on Patient Outcomes

OBJECTIVE

To examine the concordance rate of MRI findings with intraoperative and pathologic findings in patients with Placenta Accreta Spectrum (PAS), as well as the use of structured reporting, and their relationship to clinical outcomes.

METHODS

An IRB approved retrospective chart review was performed for patients with a history of cesarean delivery, a diagnosis of PAS on post-operative pathology report, and a placental MRI prior to delivery between 2008-2022. Concordance rates were calculated between final MRI, ultrasound, operative, and pathologic diagnoses, as well as impact on clinical outcomes. Quantitative variables were analyzed using a t-test. Categorical variables were analyzed using chi-squared and Fischer's exact tests.

RESULTS

A total of 59 patients met initial inclusion criteria. Of these 59 patients, 8 (13.6%) were interpreted using structured reporting. Discordance between preoperative imaging, operative findings and final pathology diagnoses were associated with increased blood loss, blood transfusion, ICU admission, and postpartum length of stay. Structured reporting was found to significantly reduce the amount of diagnostic discordance (p=.017) and was associated with decreased ICU admissions when utilized (p=.045).

CONCLUSIONS

Use of structured reporting in the interpretation of placental MRI may decrease the amount of discordance between imaging and intraoperative or pathologic diagnoses, which in our study is associated with improved patient outcomes including decreased blood loss and amount of blood transfused. Radiologists must be cognizant of key imaging features of PAS on MRI, as interpretation provides an opportunity to positively impact the quality and safety of patient care.

Psychological impact of Placenta Accreta Spectrum disorders (PAS) and risk of Post-Traumatic Stress Disorder (PTSD): A cross-sectional study

OBJECTIVE

Placenta Accreta Spectrum disorders (PAS) are a group of obstetric complications with an increasing incidence. The high maternal and neonatal morbidity and mortality associated with PAS leads to concerns about the negative psychological impact, and even the risk of developing Post-Traumatic Stress Disorder (PTSD). The aim of this study was to assess the psychological impact of PAS diagnosis and intervention during pregnancy and postpartum and its potential association with PTSD.

STUDY DESIGN

A cross-sectional study was conducted, including cases of PAS FIGO grade 2 and 3 treated at University Hospital Center São João, between 2010-2023. Only cases with histopathological confirmation after peripartum hysterectomy were included. Data were obtained from electronic medical records (Sclinic® and Obscare®). The impact of Event Scale - Revised (IES-R), a validated questionnaire, was applied, after surgery for PAS, to assess the psychological impact of PAS diagnosis and treatment.

RESULTS

Fourteen cases of PAS were identified. The mean maternal age was 36.8 years. Approximately 86 % of cases had antenatal suspicion. The mean gestational age at delivery was 34 weeks. Of the 14 women, only 11 responded to the request to participate in the study (7 interviewed in person and 4 remotely). Four women had IES-R scores indicative of high risk of PTSD (IES-R>33 points), one had an intermediate risk (IES-R between 24-32 points), and 6 fell into the low-risk category. The mean score was 22.4 points. The analysis of IES-R results by clusters showed higher scores in the intrusion category, which relates to intrusive and unwanted thoughts, images and memories.

CONCLUSION

Given the high morbidity and mortality described in women with PAS, the risk of PTSD should be acknowledged, motivating early intervention to prevent the development of severe and potentially chronic symptoms. Supportive measures and psychiatric and/or psychological follow-up should be promptly implemented, ideally by multidisciplinary teams.

First- and Second-Trimester Aneuploidy Screening Biomarkers and Risk Assessment of Placenta Previa and Accreta: A Systematic Review and Meta-Analysis

OBJECTIVE

This study evaluates differences in first and second-trimester maternal serum biomarkers for aneuploidy screening among women with placenta accreta spectrum (PAS) disorders, placenta previa, and those with normal placentation.

DATA SOURCES

A systematic review of 5 major databases up to April 2023 was conducted. Included were comparative studies analyzing mean biomarker levels in multiples of the median (MoM) among pregnant women with PAS, placenta previa, and uncomplicated pregnancies.

STUDY SELECTION

Both observational studies and randomized controlled trials were included in this meta-analysis.

DATA EXTRACTION AND DATA SYNTHESIS

Analysis of 8 retrospective studies involving 1886 participants showed significant variances in biomarker levels. In the first trimester, pregnancy-associated plasma protein-A levels were notably higher in the PAS group compared to the placenta previa group (731 patients, mean difference (MD) 0.48 MoM; 95% CI 0.23 to 0.73, P = 0.0001). Also, β-human chorionic gonadotropin levels were elevated in the placenta previa group compared to those with normal attachment (362 patients, MD 0.27 MoM; 95% CI 0.17 to 0.38, P < 0.00001). In the second trimester, alpha fetoprotein and human chorionic gonadotropin levels were significantly increased in PAS patients compared to the placenta previa and normal groups, indicating potential markers for PAS.

CONCLUSIONS

Significant differences in early pregnancy biomarker levels among women with PAS, placenta previa, and normal placentation were identified. These findings suggest potential for early screening, but further large-scale studies are essential for validation. This study underscores the need for improved screening methods for placental disorders, potentially aiding in early diagnosis and management strategies.

Evidence-based surgery for cesarean hysterectomy secondary to placenta accreta spectrum: A systematic review

OBJECTIVE

In this systematic review, we aim to propose evidence-based management for perioperative care to improve outcomes at the time of planned cesarean hysterectomy for placenta accreta spectrum, a procedure associated with significant maternal and neonatal morbidity.

DATA SOURCES

We conducted a literature search for studies published in MEDLINE (via Ovid), Embase, CINAHL, and Cochrane/CENTRAL up until February 25, 2022. The search included free-text and controlled-vocabulary terms for cesarean section, cesarean delivery, and hysterectomy.

STUDY ELIGIBILITY CRITERIA

We included randomized controlled trials, prospective cohort, retrospective cohort, and case-control studies published in English that reported on a perioperative intervention in the performance of a planned CH for PAS. Studies must have included a comparator group. Of the 8,907 studies screened in this systematic review, 79 met the inclusion criteria.

STUDY APPRAISAL AND SYNTHESIS METHODS

Articles examining each step or intervention of the CH were grouped together and reviewed qualitatively as a group. Evidence levels and recommendations were made by consensus of all authors according to the terminology of the United States Preventive Services Task Force (USPSTF). We synthesized the results of 79 articles, and provided 28 recommendations.

RESULTS

Based on USPSTF criteria, 21.4 % of the recommendations were level B (n = 6), 39.3 % were C (n = 11), 10.7 % were D (n = 3) and 28.6 % were I (n = 8). The interventions with the highest level of recommendation included delivery at a hospital with high cesarean hysterectomy volume, implementation of a standardized hospital protocol, delivery via a planned procedure, neuraxial anesthesia, and transverse skin incision (all level B recommendations by USPSTF criteria).

CONCLUSIONS

Development of a standardized hospital protocol, delivery at a center with high CH surgical volume, and utilization of neuraxial anesthesia garnered B evidence levels. Recommendations were limited due to the lack of prospective trials. Further research into the technical aspects of this high-risk procedure is warranted.

Three-dimensional ultrasound for evaluation of residual placental volume after conservative management of placenta accreta spectrum in a single tertiary center

OBJECTIVE

To evaluate the residual placental volume and correlated factors using three-dimensional ultrasound (3D) in patients with placenta accreta spectrum (PAS) after conservative management.

MATERIALS AND METHODS

From January 2005 to December 2023, we retrospectively reviewed patients with PAS who underwent prophylactic transcatheter arterial embolization and retained the placenta in situ. The residual placental volume was assessed using 3D ultrasound equipped with virtual organ computer-aided analysis. We determined the resorption rate of the residual placenta (RRRP) and analyzed correlated factors.

RESULTS

Eighteen patients with PAS were included. The mean RRRP was 152.64 ± 147.97 cm3/month. The median natural resorption time was 5.5 months. According to Spearman's correlation, only the initial placental volume was significantly associated with RRRP (p = 0.001, correlation coefficient = 0.701). Initial placental volume was not associated with postpartum hemorrhage, postpartum infection, resume of menstruation, subsequent pregnancy, or mean white blood cell count.

CONCLUSION

3D ultrasound is useful for measuring the volume of residual placenta. A larger initial placental volume was associated with a higher RRRP.

Peripartum Cesarean Hysterectomy for Placenta Percreta: A Retrospective Analysis of Cases With and Without Extrauterine Disease

Objective The aim of this study was to compare maternal morbidity and prenatal characteristics in placenta percreta cases with extrauterine disease and those with disease confined to the uterus. Methods A retrospective analysis of prospectively collected data was done at a large tertiary referral center in Egypt from October 2018 through February 2023. A total number of 73 cases who underwent primary cesarean hysterectomy with intrapartum confirmation of placenta previa percreta where there was evidence of at least placental invasion through uterine serosa (International Federation of Gynecology and Obstetrics (FIGO) grade 3) were included. Women without extrauterine disease (FIGO grade 3a) were compared to women with extrauterine disease where there was evidence of invasion of the bladder, parametrium, or both (FIGO grades 3b and 3c). Results Of 73 women included in the study, 46 women showed no evidence of extrauterine disease (group A), while the remaining 27 women had extrauterine disease (group B). The estimated amount of blood loss (mL) was 1,972 ± 671 in group A compared with 3,544 ± 899 in group B. There were no cases requiring massive transfusion in group A compared with eight of 27 cases (29.6%) in group B. Only two cases (4.3%) in group A had bladder injuries compared with 12 cases (44.4%) in group B. All 27 cases in group B required additional measures to control ongoing pelvic bleeding after hysterectomy compared with none of the cases in group A. The operating time (minutes) was 184 ± 30 in group A compared with 254 ± 42 in group B. Only five cases (10.9 %) in group A required postoperative intensive care unit admission, compared with 13 cases (48.1%) in group B. Conclusion Placenta accreta spectrum (PAS) with extrauterine disease represents the ultimate level of PAS surgery as it is more difficult, complex, and associated with the highest maternal morbidity. Highly specialized PAS centers are advised to categorize the disease into two different entities: PAS with extrauterine disease and PAS with disease confined to the uterus, as this may aid in improving the diagnostic accuracy of the severest PAS cases.

Conservative management or cesarean hysterectomy for placenta accreta spectrum in middle-income countries: A systematic review and meta-analysis

BACKGROUND

Cesarean hysterectomy is a dominant and effective approach during delivery in patients with placenta accreta spectrum (PAS). However, as hysterectomy results in a loss of fertility, conservative management is an alternative approach. However, management selection may be affected by a country's overall economic level. Thus the preferred treatment for PAS generates controversy in middle-income countries.

OBJECTIVES

We aimed to compare conservative management and cesarean hysterectomy for managing PAS in middle-income countries.

SEARCH STRATEGY

China National Knowledge Infrastructure, Wanfang Med Online Databases, Cochrane Library, Ovid MEDLINE, PubMed, Web of Science, EMBASE, clinicaltrials.gov, and Scopus were searched from inception through to October 1, 2022.

SELECTION CRITERIA

We included studies that evaluated at least one complication comparing conservative management and hysterectomy. All cases were diagnosed with PAS prenatally and intraoperatively.

DATA COLLECTION AND ANALYSIS

The primary outcomes were blood loss, adjacent organ damage, and the incidence of hysterectomy. Descriptive analyses were conducted for studies that did not meet the meta-analysis criteria. A fixed-effects model was used for studies without heterogeneity and a random-effects model was used for studies with statistical heterogeneity.

MAIN RESULTS

In all, 11 observational studies were included, with 975 and 625 patients who underwent conservative management and cesarean hysterectomy, respectively. Conservative management was significantly associated with decreased blood loss and lower risks of adjacent organ injury and hysterectomy. Conservative management significantly reduced blood transfusions, hospitalization duration, operative time, intensive care unit admission rates, and infections. There were no significant differences in the risks of coagulopathy, thromboembolism, or reoperation.

CONCLUSION

Given short-term complications and future fertility preferences for patients, conservative management appears to effectively manage PAS in middle-income countries. Owing to low levels of evidence, high heterogeneity and insufficient long-term follow-up data, further detailed studies are warranted.

Emergency delivery in pregnancies at high probability of placenta accreta spectrum on prenatal imaging: a systematic review and meta-analysis

BACKGROUND

Placenta accreta spectrum disorders are associated with a high risk of maternal morbidity, particularly when surgery is performed under emergency conditions. This study aimed to investigate the incidence of emergency cesarean delivery in patients with a high probability of placenta accreta spectrum disorders on prenatal imaging and to compare the maternal and neonatal outcomes between patients requiring emergency cesarean delivery and those not requiring emergency cesarean delivery.

DATA SOURCES

MEDLINE, Embase, Cochrane, and ClinicalTrials.gov databases were searched.

STUDY ELIGIBILITY CRITERIA

This study included case-control studies reporting the outcomes of pregnancies with a high probability of placenta accreta spectrum on prenatal imaging confirmed at birth delivered via unplanned emergency cesarean delivery vs those delivered via planned elective cesarean delivery for maternal or fetal indications. The outcomes observed were the occurrence of emergency cesarean delivery; incidence of placenta accreta and placenta increta/placenta percreta; preterm birth at <34 weeks of gestation; and indications for emergency delivery. This study analyzed and compared the outcomes between patients who underwent emergency cesarean delivery and those who underwent elective cesarean delivery, including estimated blood loss; number of packed red blood cell units transfused and blood products transfused; transfusion of more than 4 units of packed red blood cell; ureteral, bladder, or bowel injury; disseminated intravascular coagulation; relaparotomy after the primary surgery; maternal infection or fever; wound infection; vesicouterine or vesicovaginal fistula; admission to the neonatal intensive care unit; maternal death; composite neonatal morbidity; fetal or neonatal loss; Apgar score of <7 at 5 minutes; and neonatal birthweight.

METHODS

Quality assessment of the included studies was performed using the Newcastle-Ottawa Scale for case-control and cohort studies. Random-effect meta-analyses of proportions, risks, and mean differences were used to combine the data.

RESULTS

A total of 11 studies with 1290 pregnancies complicated by placenta accreta spectrum were included in the systematic review. Emergency cesarean delivery was reported in 36.2% of pregnancies (95% confidence interval, 28.1-44.9) with placenta accreta spectrum at birth, of which 80.3% of cases (95% confidence interval, 36.5-100.0) occurred before 34 weeks of gestation. The main indication for emergency cesarean delivery was antepartum bleeding, which complicated 61.8% of the cases (95% confidence interval, 32.1-87.4). Patients who underwent emergent cesarean delivery had higher estimated blood loss during surgery (pooled mean difference, 595 mL; 95% confidence interval, 116.10-1073.90; P<.001), higher number of packed red blood cells transfused (pooled mean difference, 2.3 units; 95% confidence interval, 0.99-3.60; P<.001), and higher number of blood products transfused (pooled mean difference, 3.0; 95% confidence interval, 1.10-4.90; P=.002) than patients who underwent scheduled cesarean delivery. Patients who underwent emergency cesarean delivery had a higher risk of requiring transfusion of more than 4 units of packed red blood cell (odds ratio, 3.8; 95% confidence interval, 1.7-4.9; P=.002), bladder injury (odds ratio, 2.1; 95% confidence interval, 1.1-4.0; P=.003), disseminated intravascular coagulation (odds ratio, 6.1; 95% confidence interval, 3.1-13.1; P<.001), and admission to the intensive care unit (odds ratio, 2.1; 95% confidence interval, 1.4-3.3; P<.001). Newborns delivered via emergency cesarean delivery had a higher risk of adverse composite neonatal outcomes (odds ratio, 2.6; 95% confidence interval, 1.4-4.7; P=.019), admission to the neonatal intensive care unit (odds ratio, 2.5; 95% confidence interval, 1.1-5.6; P=.029), Apgar score of <7 at 5 minutes (odds ratio, 2.7; 95% confidence interval, 1.5-4.9; P=.002), and fetal or neonatal loss (odds ratio, 8.2; 95% confidence interval, 2.5-27.4; P<.001).

CONCLUSION

Emergency cesarean delivery complicates approximately 35% of pregnancies affected by placenta accreta spectrum disorders and is associated with a higher risk of adverse maternal and neonatal outcomes. Large prospective studies are needed to evaluate the clinical and imaging signs that can identify patients with a high probability of placenta accreta spectrum at birth, patients at risk of requiring emergency cesarean delivery or peripartum hysterectomy, and patients at high risk of experiencing intrapartum hemorrhage.

Fluid resuscitation strategy in patients with placenta previa accreta: a retrospective study

Objectives

Obstetric hemorrhage is the leading cause of maternal death worldwide. Placenta previa accreta is one of the major direct causes of postpartum hemorrhage, accounting for two-thirds of obstetric hemorrhage cases. Fluid resuscitation is a life-saving procedure for patients suffering from massive hemorrhage. This study aims at evaluating the risk factors of massive hemorrhage and appropriate fluid resuscitation strategy in patients with placenta previa accreta.

Methods

This study retrospectively analyzed the risk factors for massive hemorrhage, clinical characteristics, and perinatal outcomes of patients with placenta previa accreta. Maternal noninvasively evaluated hemodynamic indicators, including maternal heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and shock index, were collected and analyzed at nine time points, from the administration of anesthesia until the end of procedures, in patients diagnosed with placenta previa accreta and receiving different fluid supply volumes.

Results

Complicated with placenta increta/percreta and gestational age of delivery later than 37 weeks are two independent risk factors of massive hemorrhage in patients with placenta previa accreta. A total of 62.27% (170/273) patients diagnosed with placenta increta/percreta had massive hemorrhage, significantly higher than those diagnosed with placenta previa accreta (5.88%, 6/102). Patients delivered after 37 weeks of gestation had significantly higher ratios (86.84%, 99/114) of massive hemorrhage compared with those delivered between 36 and 36+6 weeks of gestation (35.39%, 63/178). Maternal SBP, DBP, and MAP started to decrease immediately after the baby was delivered and reached a relatively stable trough state at 15-30 min after delivery. No statistical differences were found in hemodynamic indicators, the occurrence of hypotension, or in-hospital days after the procedure among the transfusion volumes < 30 ml/kg, 30-80 ml/kg, and ≥ 80 ml/kg groups.

Conclusion

Patients with a suspected diagnosis of placenta previa accreta should plan to deliver before 37 weeks of gestation. The ability to identify concurrent placenta increta/percreta should be improved to schedule a reasonably rapid perioperative plan. Restrictive fluid resuscitation could achieve good effects in maintaining hemodynamic stability in patients with placenta previa accreta. A time period of 15-30 min after delivery is the critical stage for fluid resuscitation.

Risk factors for placenta accreta spectrum without prior cesarean section: A case-control study in China

OBJECTIVE

To identify the risk factors for placenta accreta spectrum (PAS) disorders in women without prior cesarean section (CS).

METHODS

This retrospective case-control study investigated patients without prior CS who gave birth at Peking University Third Hospital between January 1, 2015 and December 31, 2021. Patients diagnosed with PAS according to the clinical diagnostic criteria of the 2019 International Federation of Gynecology and Obstetrics (FIGO) classification were included as the study group. Patients were matched as the control group according to delivery date and placenta previa, in a 1:2 allocation ratio. Maternal characteristics were compared between the two groups.

RESULTS

The study included 348 patients in the study group and 696 in the control group. The multivariate analysis showed that the independent risk factors of PAS consisted of operative hysteroscopy (once: adjusted odds ratio [aOR] 2.38, 95% CI 1.28-4.24, P = 0.006; twice or more: aOR 5.43, 95% CI 1.04-28.32, P = 0.045), uterine curettage (once: aOR 2.54, 95% CI 1.80-3.58, P < 0.001; twice: aOR 3.01, 95% CI 1.81-5.02, P < 0.001; three or more times: aOR 9.18, 95% CI 4.64-18.18, P < 0.001), multifetal pregnancy (aOR 5.64, 95% CI 3.01-10.57, P < 0.001), adenomyosis (aOR 2.77, 95% CI 1.23-6.22, P = 0.014), in vitro fertilization (aOR 1.51, 95% CI 1.04-2.20, P = 0.030) and pre-eclampsia (aOR 2.72, 95% CI 1.36-5.45, P = 0.005), and the independent protective factor was being multiparous (aOR 0.37, 95% CI 0.25-0.54, P < 0.001).

CONCLUSION

After controlling the effect of placenta previa, we found that patients with PAS without prior CS had unique maternal characteristics. Classification and quantification of the intrauterine surgeries they have undergone is essential for identifying high-risk patients. Early identification of high-risk groups by risk factors has the potential to improve the prognosis considerably.

Expression of sirtuins 1 in placenta, umbilical cord, and maternal serum of patients diagnosed with placenta accreta spectrum

OBJECTIVE

Placenta accreta spectrum (PAS) is defined as the attachment of the placenta to the uterine wall in varying degrees. However, the studies have explored that the underlying molecular mechanisms of the PAS are very limited. Sirtuins 1 (SIRT1) is associated with placental development by controlling trophoblast cell invasion and remodeling of spiral arteries. We aimed to determine the expression level of SIRT1 in placentas, and maternal and umbilical cord serum of patients with PAS.

METHODS

In total, 30 individuals in control, 20 patients in the placenta previa group, and 30 patients in the PAS group were included in this study. The expression levels of SIRT1 in the placentas were determined by Western blot and immunohistochemistry. Serum levels of SIRT1 in maternal and umbilical cord blood were determined by ELISA.

RESULTS

SIRT1 was significantly lower in placentas of the PAS. However, maternal and umbilical cord serum samples were not significantly different between groups.

CONCLUSION

SIRT1 may play an important role in the pathogenesis of the PAS.

Uterine sacrifice in obstetric emergencies case series: Complex cases of fetal distress, labor challenges, and life-saving interventions

This study highlights the complexities and challenges in managing obstetric emergencies, detailing critical interventions and outcomes in various high-risk cases. A retrospective analysis was conducted on four high-risk obstetric cases, each characterized by distinct complications necessitating immediate medical interventions. The study specifically examined cases involving: Fetal Distress cases where fetal health was compromised, necessitating interventions such as emergency cesarean sections. Complex Labor Dynamics detailed examinations of labor complications such as obstructed labor, precipitate labor, or labor complicated by malpresentation. Early pregnancy complications analysis focused on emergencies arising in the first trimester or early second trimester, including ectopic pregnancies and complications in pregnancies with a history of multiple cesarean sections. Severe postpartum hemorrhage investigations into cases of significant blood loss post-delivery, which required interventions ranging from pharmacological management to surgical procedures like hysterectomy. The first case concerned a 28-year-old primigravida with fetal bradycardia and thick meconium, requiring an emergency cesarean section. Postoperative complications included gestational thrombocytopenia and anemia, necessitating a total abdominal hysterectomy for severe sepsis. The newborn showed good recovery, indicated by Apgar scores. In Case 2, the need for a hysterectomy following complications during the third stage of labor was likely due to the presence of Placenta Accreta Spectrum, specifically placenta accreta or increta. While a retained placenta typically can be managed with less invasive methods, the situation escalates when the placenta is abnormally adherent to, or deeply invasive into, the uterine muscle. This can lead to uncontrollable bleeding, making a hysterectomy necessary and justified as a life-saving measure to control the severe hemorrhage while the histology confirms the diagnosis for the placenta accreta. In the third case, the decision to perform a dilation and curettage over manual vacuum aspiration was influenced by several factors. Given the severity of the patient's hemorrhage and the presence of a suspicious echogenic structure, a dilation and curettage provided a more controlled environment for thorough evacuation and immediate bleeding control. This approach was also supported by the combination technique using both Karman aspiration and a curette, allowing for effective management of complicated cases, particularly in patients with a history of multiple cesareans and potential scar tissue. The fourth case involved a 37-year-old multipara with severe postpartum hemorrhage from uterine atony, treated with surgery and managed for diabetic ketoacidosis, leading to discharge on the fourth day. This underscores the urgency and complexity of managing obstetric emergencies effectively.

Outcome evaluation of prophylactic internal iliac balloon occlusion in the management of patients with placenta accreta spectrum

PURPOSE

To evaluate outcomes and complications of prophylactic internal iliac balloon occlusion (PIIBO) in the management of patients with placenta accreta spectrum (PAS) at a large regional referral centre.

MATERIALS AND METHODS

A retrospective review of all PIIBO for PAS performed over a 12-year period (2010-2022). Information for analysis was gathered from the local RIS/PACS and clinical documentation. Collected data included patient demographics, indication for procedure, sheath insertion and removal time, total duration of balloon inflation and complications that occurred.

RESULTS

106 patients underwent temporary internal iliac artery balloon occlusion within the 12-year period. All procedures utilised bilateral common femoral artery punctures, 6Fr sheath and 5Fr Le Maitre occlusion balloons. Catheters were successfully positioned and balloons inflated in obstetric theatre following caesarean delivery in 100% of the cases. The uterus was conserved in every case. There was no maternal mortality or foetal morbidity. Twenty patients (18.9%) had some form of complication that required further intervention. Of these, 7(6.6%) had post-operative PPH, which was treated with uterine artery embolisation; and 13 (12.3%) had arterial thrombus which required aspiration thrombectomy. All procedures were technically successful with no long-term sequelae.

CONCLUSION

PIIBO plays an important part in reducing morbidity and mortality in patients with PAS. Clear pathways and multidisciplinary team working is critical in the management of these patients to ensure that any complications are dealt with promptly to avoid long-term sequelae.

Maternal outcomes of conservative management and cesarean hysterectomy for placenta accreta spectrum disorders: a systematic review and meta-analysis

BACKGROUND

Cesarean hysterectomy as a traditional therapeutic maneuver for placenta accreta spectrum (PAS) has been associated with serious morbidity, conservative management has been used in many institutions to treat women with PAS. This systematic review aims to compare maternal outcomes according to conservative management or cesarean hysterectomy in women with placenta accreta spectrum disorders.

METHODS

A systematic literature search was performed in MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science, and four Chinese databases (Chinese Biomedical Literature Database, China National Knowledge Infrastructure, Chinese Wanfang database and VIP database) to May 2024. Included studies were to be retrospective or prospective in design and compare and report relevant maternal outcomes according to conservative management (the placenta left partially or totally in situ) or cesarean hysterectomy in women with PAS. A risk ratio (RR) with 95% confidence interval (95% CI) was calculated for categorical outcomes and weighted mean difference (WMD) with 95% CI for continuous outcomes. The Newcastle-Ottawa Quality Assessment Scale was used to assess the observational studies. All analyses were performed using STATA version 18.0.

RESULTS

Eight studies were included in the meta-analysis. Compared with cesarean hysterectomy, PAS women undergoing conservative management showed lower estimated blood loss [WMD - 1623.83; 95% CI: -2337.87, -909.79], required fewer units of packed red blood cells [WMD - 2.37; 95% CI: -3.70, -1.04] and units of fresh frozen plasma transfused [WMD - 0.40; 95% CI: -0.62, -0.19], needed a shorter mean operating time [WMD - 73.69; 95% CI: -90.52, -56.86], and presented decreased risks of bladder injury [RR 0.24; 95% CI: 0.11, 0.50], ICU admission [RR 0.24; 95% CI: 0.11, 0.52] and coagulopathy [RR 0.20; 95% CI: 0.06, 0.74], but increased risk for endometritis [RR 10.91; 95% CI: 1.36, 87.59] and readmission [RR 8.99; 95% CI: 4.00, 12.21]. The incidence of primary or delayed hysterectomy rate was 25% (95% CI: 19-32, I2 = 40.88%) and the use of uterine arterial embolization rate was 78% (95% CI: 65-87, I2 = 48.79%) in conservative management.

CONCLUSION

Conservative management could be an effective alternative to cesarean hysterectomy when women with PAS desire to preserve the uterus and are informed about the limitations of conservative management.

PROSPERO ID

CRD42023484578.

Cesarean hysterectomy for placenta accreta spectrum: Surgeon specialty-specific assessment

OBJECTIVE

To assess (i) clinical and pregnancy characteristics, (ii) patterns of surgical procedures, and (iii) surgical morbidity associated with cesarean hysterectomy for placenta accreta spectrum based on the specialty of the attending surgeon.

METHODS

The Premier Healthcare Database was queried retrospectively to study patients with placenta accreta spectrum who underwent cesarean delivery and concurrent hysterectomy from 2016 to 2020. Surgical morbidity was assessed with propensity score inverse probability of treatment weighting based on surgeon specialty for hysterectomy: general obstetrician-gynecologists, maternal-fetal medicine specialists, and gynecologic oncologists.

RESULTS

A total of 2240 cesarean hysterectomies were studies. The most common surgeon type was general obstetrician-gynecologist (n = 1534, 68.5%), followed by gynecologic oncologist (n = 532, 23.8%) and maternal-fetal medicine specialist (n = 174, 7.8%). Patients in the gynecologic oncologist group had the highest rate of placenta increta or percreta, followed by the maternal-fetal medicine specialist and general obstetrician-gynecologist groups (43.4%, 39.6%, and 30.6%, P < .001). In a propensity score-weighted model, measured surgical morbidity was similar across the three subspecialty groups, including hemorrhage / blood transfusion (59.4-63.7%), bladder injury (18.3-24.0%), ureteral injury (2.2-4.3%), shock (8.6-10.5%), and coagulopathy (3.3-7.4%) (all, P > .05). Among the cesarean hysterectomy performed by gynecologic oncologist, hemorrhage / transfusion rates remained substantial despite additional surgical procedures: tranexamic acid / ureteral stent (60.4%), tranexamic acid / endo-arterial procedure (76.2%), ureteral stent / endo-arterial procedure (51.6%), and all three procedures (55.4%). Tranexamic acid administration with ureteral stent placement was associated with decreased bladder injury (12.8% vs 23.8-32.2%, P < .001).

CONCLUSION

These data suggest that patient characteristics and surgical procedures related to cesarean hysterectomy for placenta accreta spectrum differ based on surgeon specialty. Gynecologic oncologists appear to manage more severe forms of placenta accreta spectrum. Regardless of surgeon's specialty, surgical morbidity of cesarean hysterectomy for placenta accreta spectrum is significant.

Managing Placenta Accreta and Massive Hemorrhage: A Case Report on Anesthetic and Surgical Interventions

Obstetric haemorrhage is a leading cause of maternal morbidity and mortality and is a common reason for intensive care unit (ICU) admission in the postpartum. Primary postpartum obstetric haemorrhage is associated with four main causes: tone, thrombin, trauma, and tissue. Regarding the last one, placenta accreta is an abnormal invasion of the placenta into the myometrium. Early diagnosis of placenta accreta allows for better perioperative management; however, it is sometimes only identified during caesarean delivery when the placenta cannot be removed. We report a case of a 37-year-old woman with a history of caesarean section due to placenta previa, who was admitted at 36 weeks and 1 day for an urgent caesarean section (c-section) due to cord presentation. A subarachnoid block (SAB) was used for anaesthesia. It was chosen over general anaesthesia because it allows the patient to experience the birth of her children, enhances pain control, and avoids complications associated with general anaesthesia. Besides our centre has expertise in neuraxial anaesthesia. During the procedure, placental accretism and massive haemorrhage occurred, and a life-saving abdominal hysterectomy was needed. The patient experienced hypotension, partially responsive to volume replacement and vasopressors, leading to norepinephrine infusion and conversion to general anaesthesia. The surgery lasted 2.5 hours with a blood loss of 3500 ml. The patient was extubated without complications and transferred to the post anaesthesia care unit (PACU). Risk factors for placenta accreta spectrum (PAS) include previous surgery and placenta previa with a prior c-section. Antenatal diagnosis is crucial, and women with risk factors should undergo imaging at experienced centres. Delivery centres must have protocols for unexpected PAS and major obstetric haemorrhage. Both general and neuraxial anaesthesia can be suitable for managing PAS, and caesarean hysterectomy is often required to control haemorrhage. Postoperatively, adequate monitoring and care is essential. PAS management should involve excellent communication between a multidisciplinary team in specialised centres.

Validity of ICD-10 diagnosis codes for placenta accreta spectrum disorders

BACKGROUND

The 10th revision of the International Classification of Diseases, Clinical Modification (ICD-10) includes diagnosis codes for placenta accreta spectrum for the first time. These codes could enable valuable research and surveillance of placenta accreta spectrum, a life-threatening pregnancy complication that is increasing in incidence.

OBJECTIVE

We sought to evaluate the validity of placenta accreta spectrum diagnosis codes that were introduced in ICD-10 and assess contributing factors to incorrect code assignments.

METHODS

We calculated sensitivity, specificity, positive predictive value and negative predictive value of the ICD-10 placenta accreta spectrum code assignments after reviewing medical records from October 2015 to March 2020 at a quaternary obstetric centre. Histopathologic diagnosis was considered the gold standard.

RESULTS

Among 22,345 patients, 104 (0.46%) had an ICD-10 code for placenta accreta spectrum and 51 (0.23%) had a histopathologic diagnosis. ICD-10 codes had a sensitivity of 0.71 (95% CI 0.56, 0.83), specificity of 0.98 (95% CI 0.93, 1.00), positive predictive value of 0.61 (95% CI 0.48, 0.72) and negative predictive value of 1.00 (95% CI 0.96, 1.00). The sensitivities of the ICD-10 codes for placenta accreta spectrum subtypes- accreta, increta and percreta-were 0.55 (95% CI 0.31, 0.78), 0.33 (95% CI 0.12, 0.62) and 0.56 (95% CI 0.31, 0.78), respectively. Cases with incorrect code assignment were less morbid than cases with correct code assignment, with a lower incidence of hysterectomy at delivery (17% vs 100%), blood transfusion (26% vs 75%) and admission to the intensive care unit (0% vs 53%). Primary reasons for code misassignment included code assigned to cases of occult placenta accreta (35%) or to cases with clinical evidence of placental adherence without histopatholic diagnostic (35%) features.

CONCLUSION

These findings from a quaternary obstetric centre suggest that ICD-10 codes may be useful for research and surveillance of placenta accreta spectrum, but researchers should be aware of likely substantial false positive cases.

Investigation of health inequities in maternal and neonatal outcomes of patients with placenta accreta spectrum: a multicenter study

BACKGROUND

Placenta accreta spectrum is associated with significant maternal and neonatal morbidity and mortality. There is limited established data on healthcare inequities in the outcomes of patients with placenta accreta spectrum.

OBJECTIVE

This study aimed to investigate health inequities in maternal and neonatal outcomes of pregnancies with placenta accreta spectrum.

STUDY DESIGN

This multicentered retrospective cohort study included patients with a histopathological diagnosis of placenta accreta spectrum at 4 regional perinatal centers between January 1, 2013, and June 30, 2022. Maternal race and ethnicity were categorized as either Hispanic, non-Hispanic Black, non-Hispanic White, or Asian or Pacific Islander. The primary outcome was a composite adverse maternal outcome: transfusion of ≥4 units of packed red blood cells, vasopressor use, mechanical ventilation, bowel or bladder injury, or mortality. The secondary outcomes were a composite adverse neonatal outcome (Apgar score of <7 at 1 minute, morbidity, or mortality), gestational age at placenta accreta spectrum diagnosis, and planned delivery by a multidisciplinary team. Multivariable logistic regression was used to estimate the associations of race and ethnicity with maternal and neonatal outcomes.

RESULTS

A total of 408 pregnancies with placenta accreta spectrum were included. In 218 patients (53.0%), the diagnosis of placenta accreta spectrum was made antenatally. Patients predominantly self-identified as non-Hispanic White (31.6%) or non-Hispanic Black (24.5%). After adjusting for institution, age, body mass index, income, and parity, there was no difference in composite adverse maternal outcomes among the racial and ethnic groups. Similarly, adverse neonatal outcomes, gestational age at prenatal diagnosis, rate of planned delivery by a multidisciplinary team, and cesarean hysterectomy were similar among groups.

CONCLUSION

In our multicentered placenta accreta spectrum cohort, race and ethnicity were not associated with inequities in composite maternal or neonatal morbidity, timing of diagnosis, or planned multidisciplinary care. This study hypothesized that a comparable incidence of individual risk factors for perinatal morbidity and geographic proximity reduces potential inequities that may exist in a larger population.

Single-cell and spatial transcriptomics reveal alterations in trophoblasts at invasion sites and disturbed myometrial immune microenvironment in placenta accreta spectrum disorders

BACKGROUND

Placenta accreta spectrum disorders (PAS) are a severe complication characterized by abnormal trophoblast invasion into the myometrium. The underlying mechanisms of PAS involve a complex interplay of various cell types and molecular pathways. Despite its significance, both the characteristics and intricate mechanisms of this condition remain poorly understood.

METHODS

Spatial transcriptomics (ST) and single-cell RNA sequencing (scRNA-seq), were performed on the tissue samples from four PAS patients, including invasive tissues (ST, n = 3; scRNA-seq, n = 4), non-invasive normal placenta samples (ST, n = 1; scRNA-seq, n = 2). Three healthy term pregnant women provided normal myometrium samples (ST, n = 1; scRNA-seq, n = 2). ST analysis characterized the spatial expression landscape, and scRNA-seq was used to identify specific cellular components in PAS. Immunofluorescence staining was conducted to validate the findings.

RESULTS

ST slices distinctly showed the myometrium in PAS was invaded by three subpopulations of trophoblast cells, extravillous trophoblast cells, cytotrophoblasts, and syncytiotrophoblasts, especially extravillous trophoblast cells. The pathways enriched by genes in trophoblasts, smooth muscle cells (SMC), and immune cells of PAS were mainly associated with immune and inflammation. We identified elevated expression of the angiogenesis-stimulating gene PTK2, alongside the cell proliferation-enhancing gene EGFR, within the trophoblasts of PAS group. Trophoblasts mainly contributed the enhancement of HLA-G and EBI3 signaling, which is crucial in establishing immune escape. Meanwhile, SMC regions in PAS exhibited upregulation of immunomodulatory markers such as CD274, HAVCR2, and IDO1, with CD274 expression experimentally verified to be increased in the invasive SMC areas of the PAS group.

CONCLUSIONS

This study provided information of cellular composition and spatial organization in PAS at single-cell and spatial level. The dysregulated expression of genes in PAS revealed a complex interplay between enhanced immune escape in trophoblasts and immune tolerance in SMCs during invasion in PAS. These findings will enhance our understanding of PAS pathogenesis for developing potential therapeutic strategies.

A novel MRI-based diagnostic model for predicting placenta accreta spectrum

Objective To develop and evaluate a diagnostic model based on MRI signs for predicting placenta accreta spectrum. Materials and Methods A total of 155 pregnant women were included in this study, randomly divided into 104 cases in the training set and 51 cases in the validation set. There were 93 Non-PAS cases, and 62 cases in the PAS group. The training set included 62 Non-PAS cases and 42 PAS cases. Clinical factors and MRI signs were collected for univariate analysis. Then, binary logistic regression analysis was used to develop independent diagnostic models with clinical relevant risk factors or MRI signs, as well as those combining clinical risk factors and MRI signs. The ROC curve analysis was used to evaluate the diagnostic performance of each diagnostic model. Finally, the validation was performed with the validation set. Results In the training set, four clinical factors (gestity, parity, uterine surgery history, placental position) and 11 MRI features (T2-dark bands, placental bulge, T2 hypointense interface loss, myometrial thinning, bladder wall interruption, focal exophytic mass, abnormal placental bed vascularization, placental heterogeneity, asymmetric placental thickening/shape, placental ischemic infarction, abnormal intraplacental vascularity) were considered as risk factors for PAS. The AUC of the clinical diagnostic model, MRI diagnostic model, and clinical + MRI model of PAS were 0.779, 0.854, and 0.874, respectively. In the validation set, the AUC of the clinical diagnostic model, MRI diagnostic model, and clinical + MRI model of PAS were 0.655, 0.728, and 0.735, respectively. Conclusion Diagnosis model based on MRI features in this study can well predict placenta accreta spectrum.

Collateral Round Ligament Arterial Supply of Placenta Accreta Spectrum and Considerations for Prophylactic Balloon Occlusion Catheter Placement

Internal iliac artery (IIA) balloon occlusion catheters have been commonly inserted to decrease the risk of postpartum hemorrhage in placenta accreta spectrum disorders; however, there has been mixed success in clinical studies. Placement of an infrarenal aortic balloon has shown more consistent effectiveness in recent studies. A possible reason for this is collateral arterial supply to the placenta from external iliac artery branches. Retrospective chart review was conducted of angiography images during prophylactic IIA balloon occlusion catheter insertion over a 7-year period. Sixty-two individual cases were identified. Digital subtraction angiography (DSA) was performed in 32 (52%) cases, and 20 (62%) showed collateral blood supply from branches of the external iliac arteries, namely the round ligament artery. In conclusion, a high proportion of placenta accreta spectrum cases have arterial blood supply from branches of the external iliac artery, which may explain the discrepancy in effectiveness seen between IIA and infrarenal aortic sites of balloon occlusion catheter placement.

Current understanding of the pathogenesis of placenta accreta spectrum disorder with focus on mitochondrial function

AIM

The refinement of assisted reproductive technology, including the development of cryopreservation techniques (vitrification) and ovarian stimulation protocols, makes frozen embryo transfer (FET) an alternative to fresh ET and has contributed to the success of assisted reproductive technology. Compared with fresh ET cycles, FET cycles were associated with better in vitro fertilization outcomes; however, the occurrence of pregnancy-induced hypertension, preeclampsia, and placenta accreta spectrum (PAS) was higher in FET cycles. PAS has been increasing steadily in incidence as a life-threatening condition along with cesarean rates worldwide. In this review, we summarize the current understanding of the pathogenesis of PAS and discuss future research directions.

METHODS

A literature search was performed in the PubMed and Google Scholar databases.

RESULTS

Risk factors associated with PAS incidence include a primary defect of the decidua basalis or scar dehiscence, aberrant vascular remodeling, and abnormally invasive trophoblasts, or a combination thereof. Freezing, thawing, and hormone replacement manipulations have been shown to affect multiple cellular pathways, including cell proliferation, invasion, epithelial-to-mesenchymal transition (EMT), and mitochondrial function. Molecules involved in abnormal migration and EMT of extravillous trophoblast cells are beginning to be identified in PAS placentas. Many of these molecules were also found to be involved in mitochondrial biogenesis and dynamics.

CONCLUSION

The etiology of PAS may be a multifactorial genesis with intrinsic predisposition (e.g., placental abnormalities) and certain environmental factors (e.g., defective decidua) as triggers for its development. A distinctive feature of this review is its focus on the potential factors linking mitochondrial function to PAS development.

Trimester-specific diagnostic accuracy of ultrasound for detection of placenta accreta spectrum: systematic review and meta-analysis

OBJECTIVE

To assess the diagnostic accuracy of ultrasound for detecting placenta accreta spectrum (PAS) during the first trimester of pregnancy and compare it with the accuracy of second- and third-trimester ultrasound examination in pregnancies at risk for PAS.

METHODS

PubMed, EMBASE and Web of Science databases were searched to identify relevant studies published from inception until 10 March 2023. Inclusion criteria were cohort, case-control or cross-sectional studies that evaluated the accuracy of ultrasound examination performed at < 14 weeks of gestation (first trimester) or ≥ 14 weeks of gestation (second/third trimester) for the diagnosis of PAS in pregnancies with clinical risk factors. The primary outcome was the diagnostic accuracy of sonography in detecting PAS in the first trimester, compared with the accuracy of ultrasound examination in the second and third trimesters. The secondary outcome was the diagnostic accuracy of each sonographic marker individually across the trimesters of pregnancy. The reference standard was PAS confirmed at pathological or surgical examination. The potential of ultrasound and different ultrasound signs to detect PAS was assessed by computing summary estimates of sensitivity, specificity, diagnostic odds ratio and positive and negative likelihood ratios.

RESULTS

A total of 37 studies, including 5764 pregnancies at risk of PAS, with 1348 cases of confirmed PAS, were included in our analysis. The meta-analysis demonstrated that ultrasound had a sensitivity of 86% (95% CI, 78-92%) and specificity of 63% (95% CI, 55-70%) during the first trimester, and a sensitivity of 88% (95% CI, 84-91%) and specificity of 92% (95% CI, 85-96%) during the second/third trimester. Regarding sonographic markers examined in the first trimester, lower uterine hypervascularity exhibited the highest sensitivity (97% (95% CI, 19-100%)), and uterovesical interface irregularity demonstrated the highest specificity (99% (95% CI, 96-100%)). In the second/third trimester, loss of clear zone had the highest sensitivity (80% (95% CI, 72-86%)), and uterovesical interface irregularity exhibited the highest specificity (99% (95% CI, 97-100%)).

CONCLUSIONS

First-trimester ultrasound examination has similar accuracy to second- and third-trimester ultrasound examinations for the diagnosis of PAS. Routine first-trimester ultrasound screening for patients at high risk of PAS may improve detection rates and allow earlier referral to tertiary care centers for pregnancy management. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Implementation and Outcomes of a Model of Care for Placenta Accreta Spectrum in a Community-Based Private Practice

OBJECTIVE

The aim of the study is to describe a model of care and outcomes for placenta accreta spectrum (PAS) implemented in the context of a community based non-academic health system.

STUDY DESIGN

The program for management of PAS includes a multidisciplinary team approach with protocols for ultrasound assessment, diagnosis, and surgery. The program was implemented in the two largest private hospitals in the Twin Cities, Minnesota, United States. Maternal and fetal outcomes as well as cost were compared for histopathologic confirmed PAS cases before (2007-2014, n = 41) and after (2015-2017, n = 26) implementation of the PAS program.

RESULTS

Implementation of the PAS program was associated with ICU admission reductions from 53.7 to 19.2%, p = 0.005; a decrease of 1,682 mL in mean estimated blood loss (EBL) (p = 0.061); a decrease in transfusion from 85.4 to 53.9% (p = 0.005). The PAS program also resulted in a (non-significant) decrease in both surgical complications from 48.8 to 38.5% (p = 0.408) and postoperative complications from 61.0 to 42.3% (p = 0.135). The total cost of care for PAS cases in the 3 years after implementation of the program decreased by 33%.

CONCLUSION

The implementation of a model of care for PAS led by a perinatology practice at a large regional non-academic referral center resulted in reductions of ICU admissions, operating time, transfusion, selected surgical complications, overall postoperative complications, and cost.

KEY POINTS

· Implementation of a PAS care model resulted in reduced ICU admissions from 53.7% to 19.2%.. · Patient safety increased by reducing blood loss, transfusions and postoperative complications.. · This model decreased operating time, as well as total cost of care by 33%..

Cesarean hysterectomy for placenta accreta spectrum: 3-2-1 approach

Given the high risk of complications associated with cesarean hysterectomy for placenta accreta spectrum (PAS), any surgical approach and technique can yield utility in reducing the surgical morbidity. Here, we propose the 3-2-1 approach as a schema to be implemented in the proper setting for the surgical management of a PAS cesarean hysterectomy. The 3-2-1 approach begins with the surgical dissection of three anatomical landmarks that ultimately facilitate a safe surgical site for the ligation and transection of the uterine vessels. First-step is identification of the three anatomical landmarks which are (i) posterior lower uterine segment peritoneum de-serosalization, (ii) identification of the ureters laterally, and (iii) anterior bladder dissection. Posterior-to-anterior progression avoids encountering dense adhesions and hypervascularity in the anterior lower uterine segment early in the surgery. Further, allows better mobilization of the uterus to identify the anatomical landmarks laterally and anteriorly. Second-step is to deploy the 2-hand technique where the surgeon places one hand anteriorly and the other hand posteriorly in the lower uterine segment below the placental bed. The surgeon brings both hands together with flexed fingers perpendicular to the uterine tissue and gently elevates the uterus and placenta out of the pelvis and ensures safe anatomical distance to surrounding structures. Third-step is the consideration of a supracervical hysterectomy. In summary, this 3-2-1 approach to reflect the anatomy of enlarged lower uterine segment in PAS is a stepwise schema that can aid surgeons in the completion of a cesarean hysterectomy, with the goal to improve surgical outcomes.

Obstetric and haematological management and outcomes of women with placenta accreta spectrum by planned or urgent delivery: Secondary data analysis of a public referral hospital in Lebanon

BACKGROUND

Lebanon has a high caesarean section use and consequently, placenta accreta spectrum (PAS) is becoming more common.

OBJECTIVES

To compare maternal characteristics, management, and outcomes of women with PAS by planned or urgent delivery at a major public referral hospital in Lebanon.

DESIGN

Secondary data analysis of prospectively collected data.

SETTING

Rafik Hariri University Hospital (public referral hospital), Beirut, Lebanon.

PARTICIPANTS

159 pregnant and postpartum women with confirmed PAS between 2007-2020.

MAIN OUTCOME MEASURES

Maternal characteristics, management, and maternal and neonatal outcomes.

RESULTS

Out of the 159 women with PAS included, 107 (67.3%) underwent planned caesarean delivery and 52 (32.7%) had urgent delivery. Women who underwent urgent delivery for PAS management were more likely to experience antenatal vaginal bleeding compared to those in the planned group (55.8% vs 28.0%, p<0.001). Median gestational age at delivery was significantly lower for the urgent group compared to the planned (34 vs. 36 weeks, p<0.001). There were no significant differences in terms of blood transfusion rates and major maternal morbidity between the two groups; however, median estimated blood loss was significantly higher for women with urgent delivery (1500ml vs. 1200ml, p = 0.011). Furthermore, the urgent delivery group had a significantly lower birth weight (2177.5g vs. 2560g, p<0.001) with higher rates of neonatal intensive care unit (NICU) admission (53.7% vs 23.8%, p<0.001) and perinatal mortality (18.5% vs 3.8%, p = 0.005).

CONCLUSION

Urgent delivery among women with PAS is associated with worse maternal and neonatal outcomes compared to the planned approach. Therefore, early referral of women with known or suspected PAS to specialized centres is highly desirable to maximise optimal outcomes for both women and infants.

Customizing EV-CATCHER to Purify Placental Extracellular Vesicles from Maternal Plasma to Detect Placental Pathologies

Placenta Accreta Spectrum (PAS) is a life-threatening condition in which placental trophoblastic cells abnormally invade the uterus, often up to the uterine serosa and, in extreme cases, tissues beyond the uterine wall. Currently, there is no clinical assay for the non-invasive detection of PAS, and only ultrasound and MRI can be used for its diagnosis. Considering the subjectivity of visual assessment, the detection of PAS necessitates a high degree of expertise and, in some instances, can lead to its misdiagnosis. In clinical practice, up to 50% of pregnancies with PAS remain undiagnosed until delivery, and it is associated with increased risk of morbidity/mortality. Although many studies have evaluated the potential of fetal biomarkers circulating in maternal blood, very few studies have evaluated the potential of circulating placental extracellular vesicles (EVs) and their miRNA contents for molecular detection of PAS. Thus, to purify placental EVs from maternal blood, we customized our robust ultra-sensitive immuno-purification assay, termed EV-CATCHER, with a monoclonal antibody targeting the membrane Placental Alkaline Phosphatase (PLAP) protein, which is unique to the placenta and present on the surface of placental EVs. Then, as a pilot evaluation, we compared the miRNA expression profiles of placental EVs purified from the maternal plasma of women diagnosed with placenta previa (controls, n = 16); placenta lying low in uterus but not invasive) to those of placental EVs purified from the plasma of women with placenta percreta (cases, n = 16), PAS with the highest level of invasiveness. Our analyses reveal that miRNA profiling of PLAP+ EVs purified from maternal plasma identified 40 differentially expressed miRNAs when comparing these two placental pathologies. Preliminary miRNA pathway enrichment and gene ontology analysis of the top 14 upregulated and top nine downregulated miRNAs in PLAP+ EVs, purified from the plasma of women diagnosed with placenta percreta versus those diagnosed with placenta previa, suggests a potential role in control of cellular invasion and motility that will require further investigation.

Successful multidisciplinary team management of placenta accreta spectrum disorder: A referral center model in a middle-income country

OBJECTIVE

The aim of the study was to evaluate the outcomes of placenta accreta spectrum (PAS) disorder managed by a multidisciplinary care team (MCT) compared with a conventional care team (CCT) in a PAS referral center in Thailand.

METHODS

This retrospective single-center cohort study analyzed PAS management outcomes in the PSU PAS Center between January 2010 and December 2022. The incidence of hemorrhage ≥3500 mL and the composite maternal and neonatal outcomes of PAS were compared before and after the introduction of an MCT in 2016.

RESULTS

Of 227 PAS cases, 219 (96.5%) had pathological confirmation. There were 52 (22.9%) cases of placenta accreta, 119 (52.4%) cases of placenta increta, and 56 (24.7%) cases of placenta percreta. The incidence of estimated blood loss (EBL) ≥3500 mL decreased from 61.8% to 34.3% (P < 0.001) after the establishment of the MCT. The median EBL decreased from 4000 (IQR: 2600,7250) mL to 2250 (1300, 4750) mL (P < 0.001). EBL reduction was statistically significant in the accreta and increta groups (P < 0.001). Red blood cell transfusions decreased from five (3, 9) to two (1, 6) units (P < 0.001) per patient. The length of maternal hospital stays and ICU admissions were statistically shorter when PAS was managed by an MCT (P < 0.001). The length of newborn hospital and ICU stays decreased significantly (P < 0.001).

CONCLUSION

The incidence of massive postpartum hemorrhage and a composite of maternal and neonatal morbidities in pregnant women with PAS disorder improved significantly after the establishment of an MCT to manage PAS in a middle-income country setting.