Placenta Accreta Spectrum Disorders: Challenges, Risks, and Management Strategies

Insights into Congenital Body Stalk Anomaly Coupled with Placenta Accreta Conditions: A Case Report

BACKGROUND Body stalk anomaly is a rare abdominal wall defect thought to be a consequence of abnormalities in the development of cephalic, caudal, and lateral embryonic folding and defect in closure of the body wall during embryogenesis. Placenta accreta spectrum (PAS) is a general term frequently used to encompass accreta, increta, and percreta conditions. This report describes a distinct pregnancy with a body stalk abnormality and PAS. CASE REPORT A 34-year-old woman, gravida 2 para 1, with no previous abortions, was referred to the Maternal-Fetal Medicine Unit for further investigation of omphalocele at 29 weeks of gestation. Although the defect was not suspected during the first trimester scan, subsequent obstetric ultrasounds revealed a severe abdominal wall defect, kyphoscoliosis, a very rudimentary umbilical cord, and limb defects. Ultrasound examination of the placenta showed increased vascularity at the placental bed and loss of the retroplacental-myometrial radiolucent interface, leading to diagnosis of suspected body stalk anomaly, with PAS. Cesarean delivery was performed at 30 weeks, with plan for conservative treatment for PAS, including uterine-sparing surgery. Baby was born weighing 800 g and measuring 25 cm in length, with an APGAR score of 1-1. Clinical examination confirmed a very short umbilical cord and severe abdominal wall and limb defects. However, due to significant hemorrhage during surgical procedure, cesarean hysterectomy was done. CONCLUSIONS The management of body stalk anomaly with PAS is challenging. Preconception counseling is important to detect abnormalities earlier, and a multidisciplinary care team is needed to create patients' treatment plans. This congenital defect is invariably fatal.

Risk factors for emergent delivery before 36 weeks among pregnant women with placenta accreta spectrum disorder

Recent studies evaluating risk factors for emergent delivery in women with placenta accreta spectrum disorders have yielded insufficient results. A limited number of studies have evaluated prenatal ultrasound signs of the placenta accreta spectrum as risk factors and have reported inconsistent outcomes. This retrospective study included women with suspected prenatal placenta accreta spectrum who delivered between January 2007 and December 2022 at a tertiary hospital in Southern Thailand. Women who delivered electively or for conditions unrelated to the placenta accreta spectrum before 36 weeks of gestation were excluded. Women who underwent emergent delivery before 36 weeks and delivery after 36 weeks were compared using univariate and multivariable analyses. Overall, 174 women with placenta accreta spectrum were included; 45 (25.0%) underwent emergent delivery before 36 weeks of gestation. Women who delivered before 36 weeks had significantly more premature uterine contractions (41.7% vs. 7.0%, P<0.001), premature rupture of membranes (8.3% vs. 0%, P<0.05), antepartum hemorrhage (75.0% vs. 27.9%, P<0.001), and sonographic findings of placental bulging (45.8% vs. 23.3%, P=0.003) than those who delivered after 36 weeks. The number of premature uterine contractions and antepartum hemorrhage episodes (P<0.001) and more severe placenta accreta spectrum (P=0.003) were significantly associated with emergent delivery. Significant predictors of emergent delivery before 36 weeks were a history of preterm birth (odds ratio: 10.1, 95% confidence interval: 1.0-97.4), presence of premature uterine contractions (9.7, 2.9-31.5), antepartum hemorrhage (6.4, 2.2-18.3), severe placenta accreta spectrum (6.1, 1.5-25.0), and placental bulging (4.4, 1.3-14.2). In conclusion, the significant predictors of emergent delivery before 36 weeks of gestation among women with placenta accreta spectrum were a history of preterm birth, premature uterine contractions or antepartum hemorrhage before 34 weeks, placental bulging, and prenatal diagnosis of severe placenta accreta spectrum.

Super-Enhancers in Placental Development and Diseases

The proliferation of trophoblast stem (TS) cells and their differentiation into multiple lineages are pivotal for placental development and functions. Various transcription factors (TFs), such as CDX2, EOMES, GATA3, TFAP2C, and TEAD4, along with their binding sites and cis-regulatory elements, have been studied for their roles in trophoblast cells. While previous studies have primarily focused on individual enhancer regions in trophoblast development and differentiation, recent attention has shifted towards investigating the role of super-enhancers (SEs) in different trophoblast cell lineages. SEs are clusters of regulatory elements enriched with transcriptional regulators, forming complex gene regulatory networks via differential binding patterns and the synchronized stimulation of multiple target genes. Although the exact role of SEs remains unclear, they are commonly found near master regulator genes for specific cell types and are implicated in the transcriptional regulation of tissue-specific stem cells and lineage determination. Additionally, super-enhancers play a crucial role in regulating cellular growth and differentiation in both normal development and disease pathologies. This review summarizes recent advances on SEs' role in placental development and the pathophysiology of placental diseases, emphasizing the potential for identifying SE-driven networks in the placenta to provide valuable insights for developing therapeutic strategies to address placental dysfunctions.

Machine learning applications in placenta accreta spectrum disorders

This review examines the emerging applications of machine learning (ML) and radiomics in the diagnosis and prediction of placenta accreta spectrum (PAS) disorders, addressing a significant challenge in obstetric care. It highlights recent advancements in ML algorithms and radiomic techniques that utilize medical imaging modalities like magnetic resonance imaging (MRI) and ultrasound for effective classification and risk stratification of PAS. The review discusses the efficacy of various deep learning models, such as nnU-Net and DenseNet-PAS, which have demonstrated superior performance over traditional diagnostic methods through high AUC scores. Furthermore, it underscores the importance of integrating quantitative imaging features with clinical data to enhance diagnostic accuracy and optimize surgical planning. The potential of ML to predict surgical morbidity by analyzing demographic and obstetric factors is also explored. Emphasizing the need for standardized methodologies to ensure consistent feature extraction and model performance, this review advocates for the integration of radiomics and ML into clinical workflows, aiming to improve patient outcomes and foster a multidisciplinary approach in high-risk pregnancies. Future research should focus on larger datasets and validation of biomarkers to refine predictive models in obstetric care.

Efficacy of King's Combined Uterine Suture in Managing Placenta Accreta: A Retrospective Analysis

BACKGROUND Placenta accreta is a spectrum disorder that can include an abnormally adherent placenta to placental tissue that invades the endometrium and myometrium and results in hemorrhage during or after delivery. King's combined uterine suture is a combination of parauterine vascular ligation with longitudinal suturing of the lower uterine segment. This retrospective study aimed to evaluate outcomes from using King's combined uterine suture for hemostasis in 49 parturient women with placenta accreta spectrum (PAS). MATERIAL AND METHODS Clinical data of parturient women with placenta accreta in Fujian Maternal and Child Health Hospital from January 2020 to January 2023 were retrospectively collected. King's combined uterine suture ligation surgery was performed in these patients who had placenta accreta. Placenta accreta was diagnosed by the criteria for PAS. The outcomes of surgery and prognosis of newborns were analyzed. RESULTS A total of 49 parturient women were included and underwent successful intraoperative hemostasis without hysterectomy or ureteral injury. There were 4 cases of bladder rupture and 17 cases of uterine plastic surgery. The average intraoperative bleeding volume of the 49 patients was (507±162) mL. Patients had no long-term complications during postoperative follow-up. Apgar score of newborns was 9.67±0.77, and there was no asphyxia or neonatal death. CONCLUSIONS King's combined uterine suture ligation surgery is applied to placenta accreta, which not only has a definite and fast hemostatic effect, but can also effectively preserve the uterus.

Extracellular matrix and pregnancy: functions and opportunities caught in the net

The extracellular matrix is a complex network of macromolecules that support the growth and homeostatic development of organisms. By conveying multiple signaling cascades, it impacts on several biological processes and influences the behaviour of numerous cell types. During the endometrial cycle and the key events necessary for a correct embryo implantation and placentation, this bioactive meshwork is substantially modified to favour endometrial receptivity and vascular adaptation, trophoblast cell migration, and immune activation as well. A correct extracellular remodeling is fundamental for the establishment of a physiological pregnancy; indeed, the occurrence of altered matrix modifications associates with gestational disorders such as preeclampsia. In the present review, we will critically evaluate the role of pivotal matrix constituents in regulating the key steps of embryo implantation and placentation, provide up-to-date information concerning their primary mechanisms of action and discuss on their potential as a novel source of biomarkers and therapeutic targets.

Ferumoxytol-enhanced MRI of retroplacental clear space disruption in placenta accreta spectrum

INTRODUCTION

Placenta accreta spectrum (PAS) occurs when the placenta is pathologically adherent to the myometrium. An intact retroplacental clear space (RPCS) is a marker of normal placentation. In this study, we investigate use of the FDA-approved iron supplement ferumoxytol for contrast-enhanced MRI of the RPCS in mouse models of normal pregnancy and PAS. We then demonstrate the translational potential of this technique in human patients (n = 6) presenting with severe PAS (FIGO Grade 3C), moderate PAS (FIGO Grade 1), and no PAS.

METHODS

T1-weighted sequences were used to determine the optimal dose of ferumoxytol in pregnant mice. Pregnant Gab3-/- mice which demonstrate adherent placentation were imaged alongside wild-type (WT) pregnant mice with non-adherent placentation. Fe-MRI was also performed in 6 pregnant subjects using standard T1 and T2 weighted sequences and a 3D magnetic resonance angiography (MRA) sequence.

RESULTS

Ferumoxytol administered at 5 mg/kg led to strong placental enhancement in Fe-MRI images. Gab3-/- mice demonstrated loss of the hypointense region characteristic of the RPCS relative to WT mice. In human patients, Fe-MRI enabled high uteroplacental vasculature signal and quantification of the volume and signal profile in severe and moderate invasion of the placenta relative to non-PAS cases.

DISCUSSION

Ferumoxytol, an FDA-approved iron oxide nanoparticle formulation, enabled T1w MRI visualization of abnormal vascularization and loss of uteroplacental interface in a murine model of PAS. The potential of this non-invasive visualization technique was then further demonstrated in human subjects and suggests the possibility of PAS diagnosis using contrast enhanced MRI.

Diffusion lacunae: a novel MR imaging finding on diffusion-weighted imaging for diagnosing placenta accreta spectrum

OBJECTIVE

To evaluate the usefulness of novel diffusion-weighted imaging (DWI) findings for diagnosing placenta accreta spectrum (PAS).

MATERIALS AND METHODS

This retrospective study included 49 pregnant women with suspected PAS who underwent 1.5 T placental MRI. Diffusion lacunae were defined as intraplacental areas showing hypointensity on DWI and hyperintensity on the apparent diffusion coefficient map. Two radiologists evaluated the number and size of placental lacunae on DWI, and flow void in the diffusion lacunae on T2-weighted imaging. The radiologists also evaluated established MRI features of PAS described in the SAR-ESUR consensus statement. Pearson's chi-square test or Mann-Whitney U test was used to compare findings between patients with and without PAS. Interobserver reliability for DWI and established MRI features was also assessed. Optimal thresholds for the number and maximum size of diffusion lacunae for differentiating PAS from the no-PAS group were determined using receiver operating characteristic curve analyses.

RESULTS

Eighteen patients were diagnosed with PAS, and 31 patients with placental previa without PAS. The number and maximum size of diffusion lacunae were significantly larger in patients with than in patients without PAS (p < 0.0001). Combining assessment of the number of diffusion lacunae with assessment of their maximum size yielded a diagnostic performance with sensitivity, specificity and accuracy of 83%, 94% and 90%, respectively. Flow voids within the diffusion lacunae had sensitivity, specificity and accuracy of 88%, 84% and 86%, respectively.

CONCLUSION

The number and size of diffusion lacunae, and T2 flow void in diffusion lacunae may be useful findings for diagnosing 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..

Predicting the risk of cesarean hysterectomy in the management of placenta accreta spectrum disorders: a new model based on clinical findings and ultrasonography

PURPOSE

To develop a nomogram to predict the probability of cesarean hysterectomy (CH) in placenta accreta spectrum disorders (PASD) patients.

METHODS

Data from 520 patients who underwent surgery with a preliminary diagnosis of PASD at a tertiary center in southeast Turkey between 2013 and 2023 were collected, and 302 patients were included in the study. A predictive model based on clinical and ultrasonographic variables was developed using penalized maximum likelihood estimation (PMLE) regression analysis.

RESULTS

Maternal age (aOR = 1.22, 95% CI 1.08-1.44, p = 0.001) and prior uterine surgeries (aOR = 3.18, 95% CI 1.57-8.29, p = 0.001) were identified as demographic factors with an increased likelihood of CH in the nomogram, and advanced gestational weeks demonstrated a negative correlation (aOR: 0.78, 95% CI 0.56-1.02, p = 0.07). Regarding the ultrasonographic findings, the presence of the "multiple lacunae within the placenta" (aOR = 48.53, 95% CI 18.42-257.40, p < 0.001) and the "anterior placental location" (aOR = 9.60, 95% CI 2.96-50.76, p < 0.001) significantly increased the probability of CH. In addition, "hypervascularization on Doppler flow with irregularity in the line between the bladder and uterine serosa" (aOR = 7.90, 95% CI 2.66-35.12, p < 0.001) and the "retroplacental myometrial thickness of < 1 mm" (aOR = 2.49, 95% CI 0.89-8.27, p = 0.08) were related to the probability of CH. Harrell's C-index was 0.974, and the kappa value was 0.819 for the prediction model's performance evaluation.

CONCLUSION

We developed a nomogram to predict the probability of cesarean hysterectomy in patients with PASD, incorporating maternal age, gestational weeks, prior uterine surgeries, ultrasound findings, and placental location. The most closely associated findings with CH in patients with PASD were the presence of multiple placental lacunae and the anterior location of the placenta.

The Effectiveness of Bladder Filling Technique for Preventing Intraoperative Bladder Injury in Pregnant Women Undergoing Placenta Accreta Surgery: A Systematic Review

Background

Placenta accreta spectrum (PAS) disorders have become more noticeable as a serious and potentially life-threatening obstetric concern due to a rise in prevalence from 0.12% to 0.31% in recent years. New preventive measures, such as the bladder filling technique, seek to identify the bladder's borders, protect it, and displace it away from the lower uterine segment during placental removal.

Aim

To determine whether the saline bladder filling technique prevents the incidence rate of intraoperative bladder injuries among pregnant women undergoing PAS surgery.

Method

Systematic searches were conducted in PubMed, Embase, and the Cumulative Index to Nursing, Allied Health Literature and, Google Scholar from 2013 to 2023. The Cochrane Risk of Bias (ROB 2.0) and ROB in Nonrandomized Studies of Interventions tools were used to assess the quality of the selected studies.

Findings

A total of 2,094 articles were initially retrieved, and after screening, four articles met the eligibility criteria and were included in the final. The primary outcome of this systematic literature review (SLR) indicates that the utilization of the bladder filling technique was associated with a reduced occurrence of bladder injury, with an incidence range of 4.5% to 21.9% when the bladder filling technique utilized, in contrast to an incidence range of 13.1% to 32.4% when the bladder-filling technique was not utilized. Furthermore, the utilization of the bladder filling technique was found to be correlated with a reduced surgical procedure time and decreased blood loss.

Conclusion

This SLR reveals that utilizing the bladder filling technique during PAS surgeries decreases the occurrence of intraoperative bladder injury, which, in turn, reduces the occurrence of other intraoperative complications, including intraoperative blood loss. Therefore, healthcare providers and policymakers should start developing surgical protocols for the use of this technique, as it has the potential to significantly impact the outcomes of pregnant women undergoing PAS surgeries.

Assessment of serum levels and placental bed tissue expression of IGF-1, bFGF, and PLGF in patients with placenta previa complicated with placenta accreta spectrum disorders

OBJECTIVE

This study aims to detect the serum levels of IGF-1, bFGF, and PLGF and their expressions in placental bed tissues of patients with placenta previa complicated with PAS disorders.

METHODS

This case and control study included 40 multiparous pregnant women with complete placenta previa between 34 weeks and 38 weeks of gestation and they were divided into two groups: 25 patients with PAS (case group) and 15 patients without PAS (control group). The venous blood samples were collected 2 h before the cesarean section, and the placental bed tissues were taken intraoperatively at the placental implantation site and then were histologically examined to evaluate the gravity of the myometrial invasion of the placenta. According to FIGO PAS increasing grading, the 25 patients were also divided into three groups: PAS grade I group, PAS grade II group, and PAS grade III group. The concentrations of IGF-1, bFGF, and PLGF in serum were measured using ELISA, and the mean ratio of the relative mRNA expression of each biomarker in placental bed tissues was calculated using qRT-PCR. The staining intensity and the positive cells were quantitatively measured and expressed as means by using Image J software for IHC analysis.

RESULTS

IGF-1 had low serum levels and high placental bed expression in placenta previa patients with PAS disorders compared to those without PAS (all p < 0.0001). PLGF had high serum levels (p = 0.0200) and high placental bed expression (p < 0.0001) in placenta previa patients with PAS disorders compared to those without PAS. IGF-1 serum levels decreased up to PAS grade II (means were 24.3 ± 4.03, 21.98 ± 3.29, and 22.03 ± 7.31, respectively for PAS grade I, PAS grade II, PAS grade III groups, p = 0.0006). PLGF serum levels increased up to PAS grade II (means were 12.96 ± 2.74, 14.97 ± 2.56, and 14.89 ± 2.14, respectively for the three groups, p = 0.0392). However, IGF-1 and PLGF mRNA placental bed expression increased up to PAS grade III. The relative expression of mRNA means for the three groups was 3.194 ± 1.40, 3.509 ± 0.63, and 3.872 ± 0.70, respectively for IGF-1; and 2.784 ± 1.14, 2.810 ± 0.71, and 2.869 ± 0.48, respectively for PLGF (all p < 0.0001). Their IHC (immunohistochemical) staining also had increasing trends, but p > 0.05. bFGF was not significantly expressed in placenta previa with PAS disorders in most of the analysis sections (p > 0.05).

CONCLUSIONS

Low serum levels and high expression in placental bed tissues of IGF-1, or high serum levels and high expression in placental bed tissues of PLGF, may differentiate placenta previa patients with FIGO PAS grade I and PAS grade II from those without PAS disorders. However, they could not significantly predict the degree of placental invasiveness in FIGO PAS grades II and III.

Case Report of Placenta Accreta Spectrum and Arteriovenous Malformations with Successful Preservation of Fertility After Birth

Uterine arteriovenous malformations (UAVMs) that occur after birth are a rare cause of late postpartum hemorrhage. Acquired UAVMs usually occur in conjunction with pathology of the placenta. In the spectrum of placenta accreta (PAS), subinvolution of the placental bed plays an important role in its pathophysiology. We present a case of UAVM in a pregnant woman with PAS who presented with marked metrorrhagia after delivery, which was treated with classical management. Then, 35 days later, she presented to the emergency room with severe metrorrhagia. As it was suspected that she had placental remnants, an instrumental uterine control was performed, but the bleeding persisted, requiring further uterine packing and blood administration. Later, uterine artery embolization was performed with good results. Color Doppler ultrasound, magnetic resonance imaging, and angiography were the methods with the greatest diagnostic value. The differential diagnosis was as complex as the treatment. We hypothesize that UAVM may develop from minimal residual PAS in this late postpartum period. Moreover, they may recover rapidly after local surgical ablation. Considering the clinical condition, hemodynamic status, and desire to preserve fertility, we were able to avoid a hysterectomy, which is often chosen in such cases of severe, life-threatening bleeding complications.

Investigation of Nrf2-Keap-1 pathway, Sestrin 2 and oxidative stress markers in serum of patients with placenta Accreata spectrum

Placenta accreta spectrum (PAS) is an important disease group with risks such as maternal bleeding, hysterectomy, and death, which expresses the pathological adhesion of the placenta to the uterine myometrium, including placenta accreta, increta, and percreta, with an increased incidence with an increase in cesarean section rates. In this study, we aimed to investigate the Nuclear factor erythroid 2-related factor 2 (Nrf2)-Kelch-like ECH-related protein 1 (Keap1) pathway in these patients. Serum Sestrin 2, Nrf2, Keap1, glycogen synthase kinase 3β (GSK-3β), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activities and malondialdehyde-modified low-density lipoprotein (MDA-LDL) levels were performed by the Enzyme-Linked Immunosorbent Assay (ELISA) method. In the findings obtained, Nrf2, Keap1, GSK-3ß, MDA-LDL levels, SOD and GSH-Px activities were statistically significantly different in the patient group compared to the control group. While MDA-LDL values were found to be high in the patient group, Nrf2, Keap1, GSK-3ß levels, SOD and GSH-Px activities were significantly lower, except for Sestrin 2 values. In addition, when grouped according to the degree of invasion, Nrf2 levels were found to be lower and Keap1 levels higher. As a result, it was determined that the Nrf2-Keap1 pathway was disrupted in PAS patients, and the oxidant/antioxidant balance was impaired in the oxidant direction. The results show that Nrf2 and Keap1 parameters can be useful in determining the degree of placental invasion.

Possible Role of Netrin-1/Deleted in Colorectal Cancer/Vascular Endothelial Growth Factor Signaling Pathway in the Pathogenesis of Placenta Accreta Spectrum: A Case-control Study

SUMMARY

Netrin-1, an epithelial-secreted protein, plays a key role in placental formation through the promotion of cytotrophoblast proliferation and placental vascular development. These effects are mediated through several receptors, including the deleted in colorectal cancer (DCC) receptor. Placenta accreta spectrum (PAS) is an exaggerated trophoblastic invasion into the uterine myometrium. The exact etiology is unknown, but it is believed that increased trophoblastic invasion, defect decidualization, and/or abnormal angiogenesis might play a role. Our study aimed to investigate the suggested role of macrophage-induced netrin-1/DCC/vascular endothelial growth factor (VEGF) signaling in PAS pathogenesis. A total of 29 women with PAS (as cases) and 29 women with normal pregnancies (as controls) were enrolled in the study. At delivery, placental tissues of both groups were collected and processed for the evaluation of placental netrin-1 level by enzyme-linked immunoassay technique and immunohistochemical analysis of tissue DCC receptor. Placental tissue netrin-1 level of PAS cases showed a statistically significantly higher value than those in the normal group. Significant overexpression of DCC receptors, VEGF, and enhanced macrophage recruitment was noted in PAS cases in comparison to the normal placenta. Macrophage-induced netrin-1/DCC/VEGF signaling might be involved in PAS pathogenesis through the enhancement of trophoblastic angiogenesis.

A sonographic endometrial thickness <7 mm in women undergoing in vitro fertilization increases the risk of placenta accreta spectrum

BACKGROUND

The prevalence of placenta accreta spectrum, a potentially life-threatening condition, has exhibited a significant global rise in recent decades. Effective screening methods and early identification strategies for placenta accreta spectrum could enable early treatment and improved outcomes. Endometrial thickness plays a crucial role in successful embryo implantation and favorable pregnancy outcomes. Extensive research has been conducted on the impact of endometrial thickness on assisted reproductive technology cycles, specifically in terms of pregnancy rates, live birth rates, and pregnancy loss rates. However, limited knowledge exists regarding the influence of endometrial thickness on placenta accreta spectrum.

OBJECTIVE

This study aimed to evaluate the association between preimplantation endometrial thickness and the occurrence of placenta accreta spectrum in women undergoing assisted reproductive technology cycles.

STUDY DESIGN

A total of 4637 women who had not undergone previous cesarean delivery and who conceived by in vitro fertilization or intracytoplasmic sperm injection-embryo transfer treatment and subsequently delivered at the Third Affiliated Hospital of Guangzhou Medical University between January 2008 and December 2020 were included in this study. To explore the relationship between endometrial thickness and placenta accreta spectrum, we used smooth curve fitting, threshold effect, and saturation effect analysis. Multivariate logistic regression analysis was performed to evaluate the independent association between endometrial thickness and placenta accreta spectrum while adjusting for potential confounding factors. Propensity score matching was performed to reduce the influence of bias and unmeasured confounders. Furthermore, we used causal mediation effect analysis to investigate the mediating role of endometrial thickness in the relationship between gravidity and ovarian stimulation protocol and the occurrence of placenta accreta spectrum.

RESULTS

Among the 4637 women included in this study, pregnancies with placenta accreta spectrum (159; 3.4%) had significantly thinner endometrial thickness (non-placenta accreta spectrum, 10.08±2.04 mm vs placenta accreta spectrum, 8.88±2.21 mm; P<.001) during the last ultrasound before embryo transfer. By using smooth curve fitting, it was found that changes in endometrial thickness had a significant effect on the incidence of placenta accreta spectrum up to a thickness of 10.9 mm, beyond which the effect plateaued. Then, the endometrial thickness was divided into the following 4 groups: ≤7, >7 to ≤10.9, >10.9 to ≤13, and >13 mm. The absolute rates of placenta accreta spectrum in each group were 11.91%, 3.73%, 1.35%, and 2.54%, respectively. Compared with women with an endometrial thickness from 10.9 to 13 mm, the odds of placenta accreta spectrum increased from an adjusted odds ratio of 2.27 (95% confidence interval, 1.33-3.86) for endometrial thickness from 7 to 10.9 mm to an adjusted odds ratio of 7.15 (95% confidence interval, 3.73-13.71) for endometrial thickness <7 mm after adjusting for potential confounding factors. Placenta previa remained as an independent risk factor for placenta accreta spectrum (adjusted odds ratio, 11.80; 95% confidence interval, 7.65-18.19). Moreover, endometrial thickness <7 mm was still an independent risk factor for placenta accreta spectrum (adjusted odds ratio, 3.91; 95% confidence interval, 1.57-9.73) in the matched cohort after PSM. Causal mediation analysis revealed that approximately 63.9% of the total effect of gravidity and 18.6% of the total effect of ovarian stimulation protocol on placenta accreta spectrum were mediated by endometrial thickness.

CONCLUSION

The findings of our study indicate that thin endometrial thickness is an independent risk factor for placenta accreta spectrum in women without previous cesarean delivery undergoing assisted reproductive technology treatment. The clinical significance of this risk factor is slightly lower than that of placenta previa. Furthermore, our results demonstrate that endometrial thickness plays a significant mediating role in the relationship between gravidity or ovarian stimulation protocol and placenta accreta spectrum.

Additional Role of Magnetic Resonance Imaging to Ultrasound in Assessing Placenta Accreta Spectrum Disorders: A Retrospective Cross-sectional Study from Vietnam

Objectives

Placenta accreta spectrum (PAS) is commonly associated with adverse pregnancy outcomes. While ultrasound (US) is the primary imaging tool, magnetic resonance imaging (MRI) plays a crucial complementary role in assessing PAS disorders. This study aimed to evaluate the MRI features in PAS diagnosis and enhance the role of MRI in conjunction with US for better management. Additionally, the study examined the association between imaging findings and clinical outcomes.

Methods

This retrospective cross-sectional study was conducted between January 2017 and June 2022 at Tu Du Hospital, Vietnam. A total of 87 cases were eligible for inclusion. Antenatal MRI and US findings were compared to intraoperative diagnoses and/or histopathological confirmation, which is considered the gold standard. The diagnostic value of each MRI feature was calculated, and the association between MRI/US findings, estimated blood loss, and surgical methods was analyzed. Statistical significance was determined with a p-value < 0.05.

Results

Among the 87 women suspected of PAS on US, 83 were confirmed to have PAS through intraoperative diagnosis and/or histology. The mean maternal age was 35.9 5.7 years and the mean gestational age at cesarean section was 31.1 7.1 weeks. MRI sensitivity (Se) in detecting PAS ranged from 10.8-94.0%, while the specificity (Sp) ranged from 25.0-100%. Loss of retroplacental T2 dark zone demonstrated the highest diagnostic value. When combining three to six MRI signs, Se increased from 53.0-100%, and Sp from 25.0-100%. The highest Youden?(tm)s index (0.759) was observed with five MRI signs (Se = 75.9%, Sp = 100%). PAS diagnosed via MRI/US was associated with more significant blood loss during cesarean section (1000 (600-2000) mL vs. 500 (250-850) mL and 1000 (600-2000) mL vs. 300 (300-500) mL, respectively). Furthermore, the percreta type of PAS identified on MRI/US was linked to significantly higher rates of cesarean hysterectomy compared to conservative surgery (56.4% vs. 43.6% and 63.5% vs. 36.5%, respectively).

Conclusions

MRI provides a reliable diagnostic value for PAS, particularly following uncertain US findings. Depending on resource availability, a stepwise approach utilizing both imaging modalities should be considered. MRI can guide strict interdisciplinary management in cases of suspected PAS, especially percreta type. Further studies are needed to solidify the role of MRI in severe PAS cases.

Rational Design of Nanomedicine for Placental Disorders: Birthing a New Era in Women's Reproductive Health

The placenta is a transient organ that forms during pregnancy and acts as a biological barrier, mediating exchange between maternal and fetal circulation. Placental disorders, such as preeclampsia, fetal growth restriction, placenta accreta spectrum, and gestational trophoblastic disease, originate in dysfunctional placental development during pregnancy and can lead to severe complications for both the mother and fetus. Unfortunately, treatment options for these disorders are severely lacking. Challenges in designing therapeutics for use during pregnancy involve selectively delivering payloads to the placenta while protecting the fetus from potential toxic side effects. Nanomedicine holds great promise in overcoming these barriers; the versatile and modular nature of nanocarriers, including prolonged circulation times, intracellular delivery, and organ-specific targeting, can control how therapeutics interact with the placenta. In this review, nanomedicine strategies are discussed to treat and diagnose placental disorders with an emphasis on understanding the unique pathophysiology behind each of these diseases. Finally, prior study of the pathophysiologic mechanisms underlying these placental disorders has revealed novel disease targets. These targets are highlighted here to motivate the rational design of precision nanocarriers to improve therapeutic options for placental disorders.

The Underlying Molecular Mechanisms of the Placenta Accreta Spectrum: A Narrative Review

Placenta accreta spectrum (PAS) disorders are characterized by abnormal trophoblastic invasion into the myometrium, leading to significant maternal health risks. PAS includes placenta accreta (invasion < 50% of the myometrium), increta (invasion > 50%), and percreta (invasion through the entire myometrium). The condition is most associated with previous cesarean deliveries and increases in chance with the number of prior cesarians. The increasing global cesarean rates heighten the importance of early PAS diagnosis and management. This review explores genetic expression and key regulatory processes, such as apoptosis, cell proliferation, invasion, and inflammation, focusing on signaling pathways, genetic expression, biomarkers, and non-coding RNAs involved in trophoblastic invasion. It compiles the recent scientific literature (2014-2024) from the Scopus, PubMed, Google Scholar, and Web of Science databases. Identifying new biomarkers like AFP, sFlt-1, β-hCG, PlGF, and PAPP-A aids in early detection and management. Understanding genetic expression and non-coding RNAs is crucial for unraveling PAS complexities. In addition, aberrant signaling pathways like Notch, PI3K/Akt, STAT3, and TGF-β offer potential therapeutic targets to modulate trophoblastic invasion. This review underscores the need for interdisciplinary care, early diagnosis, and ongoing research into PAS biomarkers and molecular mechanisms to improve prognosis and quality of life for affected women.

Angiogenic factor-driven improvement of refractory thin endometrium with autologous platelet-rich plasma intrauterine infusion in frozen embryo transfer cycles

Objective

A beneficial effect on endometrial thickness (EMT) and improvement of pregnancy outcome after intrauterine infusion of platelet-rich plasma (PRP) has been suggested. This study assessed the effect of intrauterine PRP infusion on live birth rate and obstetrical outcomes and analyzed cytokines that can potentially improve pregnancy outcomes through PRP.

Method

This study was a prospective cohort study conducted in a university hospital fertility center. The study included ninety-one patients who had a history of two or more failed in vitro fertilization (IVF) attempts and refractory thin endometrium that remained unresponsive after at least two conventional treatments for thin endometrium. Patients were treated with an intrauterine infusion of autologous PRP between days 7 and 14 of their hormone replacement therapy-frozen embryo transfer (HRT-FET) cycle. PRP was administered at 3-day intervals until their EMT reached 7mm. After a maximum of three PRP administrations, embryo transfer (ET) was performed. The primary outcome was the live birth rate. Secondary outcomes included the implantation rate and increase in EMT compared to the previous cycle. We compared the cytokines related to angiogenesis in a patient's whole blood (WB) and PRP by utilizing a commercial screening kit.

Results

The live birth rate in the PRP treatment cycle was 20.9% (19 of 91 patients), significantly superior to the previous cycle without PRP infusion (p < 0.001). The implantation rate was also significantly higher during the PRP treatment cycle (16.4%) compared to the previous cycle (3.1%) (p < 0.001). The mean EMT post-PRP treatment was 6.1 mm, showing a significant increase of 0.8 mm (p < 0.001). Nonetheless, an increase in EMT was also observed in the non-pregnancy group. No adverse effects were reported by patients treated with autologous PRP. Cytokine array analysis confirmed marked increases in well-known pro-angiogenic factors such as Ang-1, EGF, LAP (TGF-b1), MMP-8, PDGF-AA, and PDGF-AB/PDGF-BB.

Conclusion

Intrauterine PRP infusion offers a safe and effective treatment for patients with refractory thin endometrium and implantation failures. The angiogenic cytokines present in PRP are the primary drivers of this improvement.

Prophylactic Radiologic Interventions for Postpartum Hemorrhage Control in Women With Placenta Accreta Spectrum Disorder: A Systematic Review and Meta-analysis

OBJECTIVE

To quantify the association between prophylactic radiologic interventions and perioperative blood loss during cesarean delivery in women with placenta accreta spectrum disorder through a systematic review and network meta-analysis.

DATA SOURCES

On January 3, 2023, a literature search was conducted in PubMed, EMBASE, Cochrane Library, and Web of Science. We also checked ClinicalTrials.gov retrospectively. Prophylactic radiologic interventions to reduce bleeding during cesarean delivery involved preoperative placement of balloon catheters, distal (internal or common iliac arteries) or proximal (abdominal aorta), or sheaths (uterine arteries). The primary outcome was volume of blood loss; secondary outcomes were the number of red blood cell units transfused and adverse events. Studies including women who received an emergency cesarean delivery were excluded.

METHODS OF STUDY SELECTION

Two authors independently screened citations for relevance, extracted data, and assessed the risk of bias of individual studies with the Cochrane Risk of Bias in Non-randomized Studies of Interventions tool.

TABULTATION, INTEGRATION, AND RESULTS

From a total of 1,332 screened studies, 50 were included in the final analysis, comprising 5,962 women. These studies consisted of two randomized controlled trials and 48 observational studies. Thirty studies compared distal balloon occlusion with a control group, with a mean difference in blood loss of -406 mL (95% CI, -645 to -167). Fourteen studies compared proximal balloon occlusion with a control group, with a mean difference of -1,041 mL (95% CI, -1,371 to -710). Sensitivity analysis excluding studies with serious or critical risk of bias provided similar results. Five studies compared uterine artery embolization with a control group, all with serious or critical risk of bias; the mean difference was -936 mL (95% CI, -1,522 to -350). Reported information on adverse events was limited.

CONCLUSION

Although the predominance of observational studies in the included literature warrants caution in interpreting the findings of this meta-analysis, our findings suggest that prophylactic placement of balloon catheters or sheaths before planned cesarean delivery in women with placenta accreta spectrum disorder may, in some cases, substantially reduce perioperative blood loss. Further study is required to quantify the efficacy according to various severities of placenta accreta spectrum disorder and the associated safety of these radiologic interventions.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42022320922.

Evaluation of the Management and Outcome of Patients with Retained Products of Conception after Gestational Week 23+0: A Retrospective Cohort Study

Background: Retained products of conception after childbirth or miscarriage are associated with an increased rate of maternal complications, such as abnormal vaginal bleeding and infections. Late complications may also include intrauterine adhesions, causing infertility. Surgical interventions carry a certain risk. Thus, conservative management is often discussed as an alternative. The aim of this study was to assess the clinical outcomes of patients with retained products of conception, comparing a primary surgical approach to conservative management. Methods: We conducted a retrospective cohort study of 88 patients diagnosed with retained products of conception after 23+0 weeks of gestation at the Medical University Vienna between 2014 and 2022. Results: Forty-seven (53.4%) patients underwent primary surgical management and 41 (46.6%) primary conservative management. After primary conservative treatment, a complication could be observed in 10 (24.4%) women. In contrast, complications occurred in 32 (68.1%) women in the group with primary surgical treatment (p < 0.001). The most common complication in both groups was the ongoing suspicion of retained products of conception. Patients after primary surgical treatment were significantly more likely to require a secondary change in treatment (p < 0.001). Ultimately, secondary conservative management was applied in 30 (63.8%) patients. In contrast, only nine (21.95%) patients with primary conservative management required secondary surgical management. Conclusions: Due to the high risk of complications and persistent retained products of conception, primary surgical management should only be prioritized in hemodynamically instable or septic patients.

Can immunohistochemistry improve the pathological diagnosis of placenta accreta spectrum (PAS) disorders?

PURPOSE

The term of placenta accreta spectrum (PAS) disorder includes all grades of abnormal placentation. It is crucial for pathologist provide standardized diagnostic assessment to evaluate the outcome of management strategies. Moreover, a correct and safe diagnosis is useful in the medico-legal field when it becomes difficult for the gynecologist to demonstrate the suitability and legitimacy of demolitive treatment. The purposes of our study were: (1) to assess histopathologic features according to the recent guidelines; (2) to determine if immunohistochemistry can be useful to identify extravillous trophoblast (EVT) and to measure the depth of infiltration into the myometrium to improve the diagnosis of PAS.

METHODS

The retrospective study was conducted on 30 cases of gravid hysterectomy with histopathologic diagnosis of PAS. To identify the depth of EVT, immunohistochemical stainings were performed using anti MNF116 (cytokeratins 5, 6, 8, 17, 19), actin-SM, HPL (Human Placental Lactogen), vimentin and GATA3 antibodies.

RESULTS

Our cases were graded based on the degree of invasion of the myometrium. Ten were grade 1 (33.3%), 12 grade 2 (40%) and 8 grade 3A (26.7%). EVT invasion was best seen and evident by double immunostainings with actin-SM and cytokeratins, actin-SM and HPL, actin-SM and GATA3.

CONCLUSION

The role of pathologist is decisive to determine the different grades of PAS. A better understanding of the depth of myometrial invasion can be achieved by the use of immunohistochemistry affording an important tool to obtain reproducible grading of PAS. This purpose is crucial in the setting of postoperative quality reviews and particularly in the forensic medicine field.

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.

Modified one-step conservative uterine surgery (MOSCUS) versus cesarean hysterectomy in the management of placenta accreta spectrum: A single-center retrospective analysis based on 619 Vietnamese pregnant women

OBJECTIVES

To compare maternal outcome measures in surgical management of placenta accreta spectrum (PAS)-the modified one-step conservative uterine surgery (MOSCUS), a new approach at Tu Du Hospital in Vietnam, versus cesarean hysterectomy, and to identify factors that appear to contribute to the successful outcome of the MOSCUS.

METHODS

This retrospective study was conducted at Tu Du Hospital in southern Vietnam between January 2019 and December 2020. The study enrolled all pregnant women at more than 28 weeks of pregnancy with a diagnosis of PAS who underwent either a cesarean hysterectomy or a uterus-preserving approach using the MOSCUS method.

RESULTS

The prevalence of PAS at our single tertiary referral hospital was 0.4% (619 PAS cases/132 518 births) in 2 years. Among 296 patients, the surgical time duration, estimated blood loss, and red blood cell transfusion in the MOSCUS group (n = 217) were all significantly less than in the cesarean hysterectomy group (n = 79) (152.72 ± 42.23 vs 185.13 ± 58.22 min, 1000 vs 1500 mL, and 500 vs 710 mL, respectively). Intraoperatively, the rate of visceral injuries in the hysterectomy group was higher than that in the MOSCUS group (P < 0.001). However, the rate of postoperative infection was higher in the MOSCUS group than in the cesarean hysterectomy group (P = 0.012). Of a total of 217 cases managed using the MOSCUS management, 24 required a secondary hysterectomy; the success rate was 88.9% (95% confidence interval [CI] 84.3%-93.1%). Some of the primary factors associated with the success of MOSCUS included maternal age less than 35 years, planned surgery, severity of PAS, and estimated blood loss during surgery (odds ratio [OR] 5.16, 95% CI 1.96-13.59; OR 3.05, 95% CI 1.08-8.62; OR 3.62, 95% CI 1.19-10.98; and OR 49.66, 95% CI 11.16-221.02, respectively; P < 0.05).

CONCLUSION

MOSCUS is an acceptable alternative to cesarean hysterectomy in many patients diagnosed with PAS. This new surgical management of PAS resulted in the preservation of the uterus, and a favorable outcome in nearly 9 out of 10 pregnant women. We believe that MOSCUS can be safely offered for the management of PAS in referral hospital settings.

Neonatal outcomes in the surgical management of placenta accreta spectrum disorders: a retrospective single-center observational study from 468 Vietnamese pregnancies beyond 28 weeks of gestation

BACKGROUND

Placenta accreta spectrum disorders (PASDs) increase the mortality rate for mothers and newborns over a decade. Thus, the purpose of the study is to evaluate the neonatal outcomes in emergency cesarean section (CS) and planned surgery as well as in Cesarean hysterectomy and the modified one-step conservative uterine surgery (MOSCUS). The secondary aim is to reveal the factors relating to poor neonatal outcomes.

METHODS

This was a single-center retrospective study conducted between 2019 and 2020 at Tu Du Hospital, in the southern region of Vietnam. A total of 497 pregnant women involved in PASDs beyond 28 weeks of gestation were enrolled. The clinical outcomes concerning gestational age, birth weight, APGAR score, neonatal intervention, neonatal intensive care unit (NICU) admission, and NICU length of stay (LOS) were compared between emergency and planned surgery, between the Cesarean hysterectomy and the MOSCUS. The univariate and multivariable logistic regression were used to assess the adverse neonatal outcomes.

RESULTS

Among 468 intraoperatively diagnosed PASD cases who underwent CS under general anesthesia, neonatal outcomes in the emergency CS (n = 65) were significantly poorer than in planned delivery (n = 403). Emergency CS increased the odds ratio (OR) for earlier gestational age, lower birthweight, lower APGAR score at 5 min, higher rate of neonatal intervention, NICU admission, and longer NICU LOS ≥ 7 days with OR, 95% confidence interval (CI) were 10.743 (5.675-20.338), 3.823 (2.197-6.651), 5.215 (2.277-11.942), 2.256 (1.318-3.861), 2.177 (1.262-3.756), 3.613 (2.052-6.363), and 2.298 (1.140-4.630), respectively, p < 0.05. Conversely, there was no statistically significant difference between the neonatal outcomes in Cesarean hysterectomy (n = 79) and the MOSCUS method (n = 217). Using the multivariable logistic regression, factors independently associated with the 5-min-APGAR score of less than 7 points were time duration from the skin incision to fetal delivery (min) and gestational age (week). One minute-decreased time duration from skin incision to fetal delivery contributed to reduce the risk of adverse neonatal outcome by 2.2% with adjusted OR, 95% CI: 0.978 (0.962-0.993), p = 0.006. Meanwhile, one week-decreased gestational age increased approximately two fold odds of the adverse neonatal outcome with adjusted OR, 95% CI: 1.983 (1.600-2.456), p < 0.0001.

CONCLUSIONS

Among pregnancies with PASDs, the neonatal outcomes are worse in the emergency group compared to planned group of cesarean section. Additionally, the neonatal comorbidities in the conservative surgery using the MOSCUS method are similar to Cesarean hysterectomy. Time duration from the skin incision to fetal delivery and gestational age may be considered in PASD surgery. Further data is required to strengthen these findings.

Roadmap to safety: a single center study of evidence-informed approach to placenta accreta spectrum

Objective

To assess the impact of an evidence-informed protocol for management of placenta accreta spectrum (PAS).

Methods

This was a retrospective cohort study of patients who underwent cesarean hysterectomy (c-hyst) for suspected PAS from 2012 to 2022 at a single tertiary care center. Perioperative outcomes were compared pre- and post-implementation of a standardized Multidisciplinary Approach to the Placenta Service (MAPS) protocol, which incorporates evidence-informed perioperative interventions including preoperative imaging and group case review. Intraoperatively, the MAPS protocol includes placement of ureteral stents, possible placental mapping with ultrasound, and uterine artery embolization by interventional radiology. Patients suspected to have PAS on prenatal imaging who underwent c-hyst were included in the analysis. Primary outcomes were intraoperative complications and postoperative complications. Secondary outcomes were blood loss, need for ICU, and length of stay. Proportions were compared using Fisher's exact test, and continuous variables were compared used t-tests and Mood's Median test.

Results

There were no differences in baseline demographics between the pre- (n = 38) and post-MAPS (n = 34) groups. The pre-MAPS group had more placenta previa (95% pre- vs. 74% post-MAPS, p = 0.013) and prior cesarean sections (2 prior pre- vs. 1 prior post-MAPS, p = 0.012). The post-MAPS group had more severe pathology (PAS Grade 3 8% pre- vs. 47% post-MAPS, p = 0.001). There were fewer intraoperative complications (39% pre- vs.3% post-MAPS, p < 0.001), postoperative complications (32% pre- vs.12% post-MAPS, p = 0.043), hemorrhages >1l (95% pre- vs.65% post-MAPS, p = 0.001), ICU admissions (59% pre- vs.35% post-MAPS, p = 0.04) and shorter hospital stays (10 days pre- vs.7 days post-MAPS, p = 0.02) in the post-MAPS compared to pre-MAPS patients. Neonatal length of stay was 8 days longer in the post-MAPS group (9 days pre- vs. 17 days post-MAPS, p = 0.03). Subgroup analyses demonstrated that ureteral stent placement and uterine artery embolization (UAE) may be important steps to reduce complications and ICU admissions. When comparing just those who underwent UAE, patients in the post-MAPS group experienced fewer hemorrhages greater five liters (EBL >5l 43% pre- vs.4% post-MAPS, p = 0.007).

Conclusion

An evidence-informed approach to management of PAS was associated with decreased complication rate, EBL >1l, ICU admission and length of hospitalization, particularly for patients with severe pathology.

A new technique to preserve the uterus in patients with placenta accreta spectrum disorders

BACKGROUND

Placenta accreta spectrum disorders are associated with substantial maternal morbidity and mortality. Despite a preoperative diagnosis, the rate of complications remains high, and the condition is generally associated with the need for a hysterectomy.

OBJECTIVE

This study aimed to evaluate the outcomes of a new uterine-preserving technique (called the combined approach, including surgical hemostasis, bilateral ligation of the descending branches of the uterine arteries, and hemostatic external supraplacental stitch with the use of the Zhukovsky double-balloon tamponade in patients with placenta accreta spectrum disorders) during cesarean delivery in women with placenta accreta spectrum disorders vs the surgical technique used until 2014.

STUDY DESIGN

This retrospective cohort study included 147 patients with placenta accreta spectrum disorders who were divided into 2 groups: the study group (n=95) is to undergo cesarean delivery using the combined approach, and the control group (n=52) is to undergo the surgical technique used until 2014, which included bilateral uterine artery ligation, which is the transfusion of plasma, red blood cells, platelets, and protease inhibitors.

RESULTS

The volume of blood loss was 1.5-fold lower (P=.0010), the number of blood transfusions was 5.1-fold lower (P=.026), and the rate of bladder injuries was 19-fold lower (P=.012) in the study group than that in the control group. The duration of hospital stay after delivery was 4 days lesser (P=.001) and the number of hysterectomies was 4.5-fold lower in the study group than in the control group (P=.023). The study groups did not differ in terms of placenta accreta spectrum type.

CONCLUSION

The combined approach during cesarean delivery proved to be more effective than the surgical technique used until 2014 in reducing the number of hysterectomies, blood loss volume, number of blood transfusions, and duration of hospital stay in patients with placenta accreta spectrum disorders.

Anaemia and red blood cell transfusion in women with placenta accreta spectrum: an analysis of 38,060 cases

Placenta accreta spectrum (PAS) has become a significant life-threatening issue due to its increased incidence and associated morbidity and mortality. Pregnancy is often associated with states of anaemia, and severe maternal haemorrhage represents a major risk factor for red blood cell (RBC) transfusion. The present study retrospectively analyzed the prevalence of anaemia, transfusion requirements and outcome in women with PAS. Using data from the German Statistical Office pregnant patients with deliveries hospitalized between January 2012 and December 2021 were included. Primary outcome was the prevalence of anemia and administration of RBCs. Secondary outcome were complications in women with PAS who received RBC transfusion. In total 6,493,606 pregnant women were analyzed, of which 38,060 (0.59%) were diagnosed with PAS. The rate of anaemia during pregnancy (60.36 vs. 23.25%; p < 0.0001), postpartum haemorrhage (47.08 vs. 4.41%; p < 0.0001) and RBC transfusion rate (14.68% vs. 0.72%; p < 0.0001) were higher in women with PAS compared to women without PAS. Women with PAS who had bleeding and transfusion experienced significantly more peripartum complications than those who did not. A multiple logistic regression revealed that the probability for RBC transfusion in all pregnant women was positively associated with anaemia (OR 21.96 (95% CI 21.36-22.58)). In women with PAS, RBC transfusion was positively associated with the presence of renal failure (OR 11.27 (95% CI 9.35-13.57)) and congestive heart failure (OR 6.02 (95% CI (5.2-7.07)). Early anaemia management prior to delivery as well as blood conservation strategies are crucial in women diagnosed with PAS.

Primary and secondary postpartum haemorrhage: a review for a rationale endovascular approach

Postpartum haemorrhage (PPH) is a significant cause of maternal mortality globally, necessitating prompt and efficient management. This review provides a comprehensive exploration of endovascular treatment dimensions for both primary and secondary PPH, with a focus on uterine atony, trauma, placenta accreta spectrum (PAS), and retained products of conception (RPOC). Primary PPH, occurring within 24 h, often results from uterine atony in 70% of causes, but also from trauma, or PAS. Uterine atony involves inadequate myometrial contraction, addressed through uterine massage, oxytocin, and, if needed, mechanical modalities like balloon tamponade. Trauma-related PPH may stem from perineal injuries or pseudoaneurysm rupture, while PAS involves abnormal placental adherence. PAS demands early detection due to associated life-threatening bleeding during delivery. Secondary PPH, occurring within 24 h to 6 weeks postpartum, frequently arises from RPOC. Medical management may include uterine contraction drugs and hemostatic agents, but invasive procedures like dilation and curettage (D&C) or hysteroscopic resection may be required.Imaging assessments, particularly through ultrasound (US), play a crucial role in the diagnosis and treatment planning of postpartum haemorrhage (PPH), except for uterine atony, where imaging techniques prove to be of limited utility in its management. Computed tomography play an important role in evaluation of trauma related PPH cases and MRI is essential in diagnosing and treatment planning of PAS and RPOC.Uterine artery embolization (UAE) has become a standard intervention for refractory PPH, offering a rapid, effective, and safe alternative to surgery with a success rate exceeding 85% (Rand T. et al. CVIR Endovasc 3:1-12, 2020). The technical approach involves non-selective uterine artery embolization with resorbable gelatine sponge (GS) in semi-liquid or torpedo presentation as the most extended embolic or calibrated microspheres. Selective embolization is warranted in cases with identifiable bleeding points or RPOC with AVM-like angiographic patterns and liquid embolics could be a good option in this scenario. UAE in PAS requires a tailored approach, considering the degree of placental invasion. A thorough understanding of female pelvis vascular anatomy and collateral pathways is essential for accurate and safe UAE.In conclusion, integrating interventional radiology techniques into clinical guidelines for primary and secondary PPH management and co-working during labour is crucial.

MRI-Based Risk Factors for Adverse Maternal Outcomes in Prophylactic Aortic Balloon Occlusion for Placenta Accreta Spectrum and Placenta Previa

PURPOSE

We previously reported that T2 dark bands and placental bulges observed in magnetic resonance imaging (MRI) can predict adverse maternal outcomes in patients with placenta accreta spectrum (PAS) and placenta previa undergoing prophylactic balloon occlusion of the internal iliac artery. On the other hand, the risk factors associated with the use of prophylactic aortic balloon occlusion (PABO) have not been sufficiently investigated. This retrospective study aimed to identify MRI-based risk factors associated with adverse maternal outcomes in the context of PABO during a cesarean section (CS) for PAS and placenta previa.

MATERIALS AND METHODS

Ethical approval was obtained for a data analysis of 40 patients diagnosed with PAS and placenta previa undergoing PABO during a CS. Clinical records, MRI features, and procedural details were examined. The inclusion criteria for the massive bleeding group were as follows: an estimated blood loss (EBL) > 2500 mL, packed red blood cell (pRBC) transfusion (>4 units), and the need for a hysterectomy or transcatheter arterial embolization after delivery. The massive and nonmassive bleeding groups were compared.

RESULTS

Among the 22 patients, those in the massive bleeding group showed significantly longer operative durations, a higher EBL (p < 0.001), an increased number of pRBC transfusions (p < 0.001), and prolonged postoperative hospital stays (p < 0.05). T2 dark bands on MRI were significant predictors of adverse outcomes (p < 0.05).

CONCLUSION

T2 dark bands on MRI were crucial predictors of adverse maternal outcomes in patients undergoing PABO for PAS or placenta previa during a CS. Recognizing these MRI features proactively indicates the need for effective management strategies during childbirth and emphasizes the importance of further prospective studies to validate and enhance these findings.

Evaluation of the holding-up uterus technique for placenta accreta spectrum cesarean hysterectomy in shocked patients with a high shock index: a case series study

BACKGROUND

Placenta accreta spectrum (PAS) cesarean hysterectomy is performed under conditions of shock and can result in serious complications. This study aimed to evaluate the usefulness of the "Holding-up uterus" surgical technique with a shock index (S.I.) > 1.5.

METHODS

Twelve patients who underwent PAS cesarean hysterectomy were included in the study.

RESULTS

Group I had S.I. > 1.5, and group II had S.I. ≤ 1.5. Group I had more complications, but none were above Grade 3 or fatal. Preoperative scheduled uterine artery embolization did not result in serious complications, but three patients who had emergency common iliac artery balloon occlusion (CIABO) and a primary total hysterectomy with S.I. > 1.5 had postoperative Grade 2 thrombosis. Two patients underwent manual ablation of the placenta under CIABO to preserve the uterus, both with S.I. > 1.5.

CONCLUSIONS

The study found that the "Holding-up uterus" technique was safe, even in critical situations with S.I. > 1.5. CIABO had no intervention effect. The study also identified assisted reproductive technology pregnancies with a uterine cavity length of less than 5 cm before conception as a critical factor.

Risk factors for non-previa placenta accreta spectrum in pregnancies conceived through frozen embryo transfer during a hormone replacement cycle in Japan

Purpose

Non-previa placenta accreta spectrum (PAS) is associated with assisted reproductive technology (ART), particularly frozen embryo transfer during hormone replacement therapy (HRC-FET). We especially aimed to evaluate the prevalence and risk factors for non-previa PAS in HRC-FET pregnancies.

Methods

Overall, 279 women who conceived through ART at three ART facilities and delivered at a single center were included in this retrospective study. Data regarding endometrial thickness at embryo transfer, previous histories, and type of embryo transfer-HRC-FET, frozen embryo transfer during a natural ovulatory cycle (NC-FET), and fresh embryo transfer (Fresh-ET)-were collected. Univariable logistic regression analyses were conducted.

Results

The prevalence of non-previa PAS was 27/192 (14.1%) in the HRC-FET group and 0 (0.0%) in both the NC-FET and Fresh-ET groups. Significantly high odds ratio [95% confidence interval] of non-previa PAS was associated with a history of artificial abortion (6.45 [1.98-21.02]), endometrial thickness <8.0 mm (6.11 [1.06-35.12]), resolved low-lying placenta (5.73 [2.13-15.41]), multiparity (2.90 [1.26-6.69]), polycystic ovarian syndrome (2.62 [1.02-6.71]), and subchorionic hematoma (2.49 [1.03-6.04]).

Conclusions

A history of artificial abortion, endometrial thickness <8.0 mm, and resolved low-lying placenta may help in antenatal detection of a high-risk population of non-previa PAS in HRC-FET pregnancies.

Associations of characteristics of previous induced abortion with different grades of current placenta accreta spectrum disorders

OBJECTIVE

Induced abortion could increase the risk of placenta accreta spectrum (PAS) in the next pregnancy. We aimed to explore the associations between characteristics of previous induced abortion and grades of current PAS.

METHODS

A retrospective case-control study was performed in eligible pregnant women with PAS between January 2014 and June 2022. Data collected included demographics, obstetric characteristics, and information on previous induced abortion.

RESULTS

The study included 211 pregnant women, with 51 and 160 in the invasive (placenta increta or percreta) and adherence (placenta creta) PAS groups, respectively. The risk of invasive PAS was 14.3-fold higher in patients with abnormal vaginal bleeding after abortion (odds ratio = 14.3, 95% confidence interval 5.6-36.4, p < .01) than those without abnormal vaginal bleeding and approximately 5.8-fold higher in patients with the last induced abortion ≥5 years ago than those within 5 years (odds ratio = 5.8, 95% confidence interval 2.2-15.2, p < .01). The risk of invasive PAS was 13.4-fold higher in patients with placenta attached to uterine cornu than patients with the placenta attached to uterine wall (odds ratio = 17.5, 95% confidence interval 5.5-55.5, p < .01). The number of previous induced abortions, hospital grades, and gestational age at abortion were not different between two groups.

CONCLUSION

In pregnant women with a history of induced abortion, abnormal vaginal bleeding after induced abortion and prolonged duration after the last induced abortion increased the risk for invasive PAS in the current pregnancy. The number of previous induced abortions and gestational age at abortion had no relation to the grades of PAS.

Periostin promotes extensive neovascularization in placenta accreta spectrum disorders via Notch signaling

OBJECTIVE

Extensive neovascularization, closely linked to massive intraoperative blood loss, is a pathological hallmark of placenta accreta spectrum (PAS) cases. This study aims to explore proteins related to neovascularization and elucidate their regulatory roles in PAS, enhancing our understanding of this condition.

METHODS

The isobaric tags for relative and absolute quantitation technique were used to identify and quantify the differentially expressed proteins in placentas from PAS and healthy pregnant women. Immunofluorescence staining and western blot analysis were conducted to determine the protein expression and localization. Gain-of-function experiments were used to conduct cell proliferation and migration assays. In addition, the tube formation assay was performed to evaluate angiogenesis in vitro. The Notch inhibitor DAPT was used to determine the involvement of Notch signaling in angiogenesis in PAS.

RESULTS

Periostin (POSTN) exhibited higher expression in PAS placentas than in normal placentas. Moreover, the overexpression of POSTN in endothelial cells promoted cell proliferation, mobility, and endothelial angiogenesis via the Notch signaling pathway in vitro.

CONCLUSION

Elevated POSTN expression in PAS is associated with increased angiogenesis, indicating its potential as a molecular marker for significant intraoperative blood loss.

Reproductive outcome after cesarean scar pregnancy

Cesarean scar pregnancy (CSP) rate is rising worldwide, in parallel with the rising rates of cesarean delivery. Multiple therapeutic strategies and a timely diagnosis have led to a successful management in most cases, with many women preserving fertility after treatment. Despite this, still little is known regarding pregnancy outcomes after a CSP. The main adverse outcomes reported after CSP are recurrence of CSP, miscarriage, preterm birth, placenta accreta spectrum (PAS) disorders and uterine rupture. In addition, little is known about the influence of the different treatments on subsequent pregnancy outcomes after a CSP. Being aware of the impact of the different management strategies on the fertility outcomes is highly relevant to counsel pregnant women after a CSP. The aim of this manuscript is to provide an up-to-date review of the reproductive outcomes of women with a history of CSP and of the influence of various treatments on subsequent pregnancy outcomes.

Placenta accreta spectrum with severe morbidity: fibrosis associated with cervical-trigonal invasion

OBJECTIVE

Describe the clinical-surgical results of patients with PAS in the low-posterior cervical-trigonal space associated with fibrosis (PAS type 4) compared with PAS types in other locations (Types 1, upper bladder, 2 in upper parametrium) and in particular with PAS type 3, corresponding to dissectible cervical-trigonal invasion. The clinical-surgical results of using a standard hysterectomy were analyzed with a modified subtotal hysterectomy (MSTH) in patients with PAS type 4.

MATERIAL AND METHODS

A descriptive, retrospective, multicenter study included 337 patients of PAS; thirty-two corresponding to PAS type 4, from three PAS reference hospitals, CEMIC, Buenos Aires, Argentina, Fundación Valle de Lili, Cali, Colombia, and Dr. Soetomo General Hospital, Surabaya, Indonesia, between January 2015 and December 2020. PAS was diagnosed by abdominal and transvaginal ultrasound and topographically characterized by ultrafast T2 weighted MRI. In persistent macroscopic hematuria after MSTH, the surgeon performs an intentional cystotomy and uses a square compression suture to achieve the hemostasis inside the bladder wall.According to a PAS topographical classification, the patients with low-vesical cervical involvement compared with PAS located in relation with the upper blader (type1), upper parametrium (type 2 upper), and also with PAS situated in the lower vesical-trigon space (type 3). PAS 3 and 4 are located in identical area, but in type 3, group A, the vesicouterine space was dissectible, and in type 4, group B, significant fibrosis made surgical dissection extremely challenging. Furthermore, group B was divided into patients treated with total hysterectomy (HT) and those treated with a modified subtotal hysterectomy (MSTH). The surgical requirements to perform an MSHT included the availability of proximal vascular control at the aortic level (internal manual aortic compression, aortic endovascular balloon, aortic loop, or aortic cross-clamping). Then surgeon performed an upper segmental hysterotomy, avoiding the abnormal placenta invasion area; after that, the fetus was delivered, and the umbilical cord was ligated.After uterine exteriorization, the surgeon applies a continuous circular suture with number 2 polyglactin 910, taking some portions of the myometrium -to avoid unintentional slipping- around the lower uterine segment and a 3-4 cm proximal to the abnormal adhesion of the placenta. After tightening hard the circular suture, the uterine segment was circumferentially cut, three centimeters proximal to the circular hemostatic sutures. Next, the surgery follows the upper steps of conventional hysterectomy without changes. Additionally, the histological presence of fibrosis was examined in all samples.

RESULTS

Modified subtotal hysterectomy in patients with PAS type 4 (cervical-trigonal fibrosis) resulted in a significant clínico-surgical improvement over total hysterectomy. The median operative time and intraoperative bleeding were 140 min (IQR 90--240) and 1895 mL (IQR 1300-2500) in patients undergoing modified subtotal hysterectomy, and 260 min (IQR 210-287) and 2900 mL (IQR 2150-5500) in patients treated with total hysterectomy, respectively. The complication rate was 20% for MSHT and 82.3% for patients with a total hysterectomy.

CONCLUSIONS

PAS in the cervical trigonal area associated with fibrosis implies a greater risk of complications due to uncontrollable bleeding and organ damage. MSTH is associated with lower morbidity and difficulties in PAS type 4. Prenatal or intrasurgical diagnosis is essential to plan surgical alternatives to improve the results.

Nanotechnological approaches for the treatment of placental dysfunction: recent trends and future perspectives

The transitory placenta develops during pregnancy and mediates the blood flow between the mother and the developing baby. Placental dysfunction, including but not limited to placenta accreta spectrum, fetal growth restriction, preeclampsia and gestational trophoblastic disease, arises from abnormal placental development and can result in significant adverse maternal and fetal health outcomes. Unfortunately, there is a lack of treatment alternatives for these disorders. Nanocarriers offer versatility, including extended circulation, organ-specific targeting and intracellular transport, finely tuning therapeutic placental interactions. This thorough review explores nanotechnological strategies for addressing placental disorders, encompassing dysfunction insights, potential drug-delivery targets and recent strides in placenta-targeted nanoparticle (NP) therapies, instilling hope for effective placental malfunction treatment.

Effective training program for antenatal diagnosis of placenta accreta spectrum disorder

OBJECTIVE

To develop and evaluate a training program for diagnosing placenta accreta spectrum (PAS) disorder in obstetrics/gynecology and radiology residents.

METHODS

This single-center prospective study was based on 177 ultrasound images of pathologically confirmed PAS extracted from 534 cases of placenta previa suspicious for PAS. First- to third-year residents were evaluated before training to assess experience and ability to diagnose PAS. They attended a principal lecture followed by weekly self-study exercises over 5 weeks. Post-course tests evaluated the efficacy of the training program for improving diagnosis of PAS after the program.

RESULTS

Twenty-three (38.3%) obstetrics/gynecology and 37 (61.7%) radiology residents were trained. Before the training program, 98.3% reported minimal experience and 100% low confidence to correctly diagnose PAS. During the program, the overall accuracy of all participants in diagnosing PAS increased from 71.3% before to 95.2% after training (P < 0.001). Regression analyses showed that ability to diagnose PAS increased 2.52-fold (P < 0.001) following the program. The retention of knowledge at 1, 3, and 6 months posttest was 84.7%, 87.5%, and 87.7%, respectively.

CONCLUSION

An antenatal diagnosis of PAS training program can be effective as a residency training program, considering the globally rising cesarean delivery rates.

Evaluation and Comparison of Sensitivity and Specificity of Ultrasonography in Placenta Accreta Diagnosis in the Second and Third Trimesters

Background

Ultrasound is the selected technique for the detection of placenta accreta spectrum (PAS). This method can detect PAS in 80%-50% of cases. This study aimed to assess and compare the sensitivity and specificity of ultrasonography in the diagnosis of PAS after the first trimester.

Materials and Methods

In this prospective study that was performed in 2020-2021 on 79 patients at high risk of PAS, all cases underwent ultrasonography in both 18-22 weeks of gestational age (GA) and 32-34 weeks of GA for evaluation of accreta. As per the risk factors, the delivery plan for all mothers was cesarean section. During the cesarean section, the placenta was examined for accreta, and if it was attached to the uterus, a diagnosis of placenta accreta was ascertained and a total abdominal hysterectomy was performed if the patient's bleeding was not controlled during the operation. The final diagnosis of PAS was made based on the pathology report.

Results

Ultrasound evaluation for PAS in 18-22 weeks of GA had 79.17% specificity, 51.61% sensitivity, 61.54% positive predictive value, and 71.70% negative predictive value. Ultrasound imaging for PAS in 32-34 weeks of GA had 60.8% specificity, 90% sensitivity, 62.52% positive predictive value, and 90.33% negative predictive value.

Conclusion

It should be concluded that PAS is a critical condition and if the patient is diagnosed in the second or third trimester, special strategies should be applied.

rSO2 Measurement Using NIRS for Lower-Limb Blood Flow Monitoring and Estimation of Safe Balloon Occlusion/Deflation Time in Patients with PAS Who Underwent PBOA during CS

We examined the utility of regional oxygen saturation (rSO2) measurement using near-infrared spectroscopy (NIRS) for monitoring lower-limb blood flow and estimate the safe balloon occlusion/deflation time in patients with PAS who underwent prophylactic balloon occlusion of the abdominal artery (PBOA) during cesarean section (CS). During CS, the NIRS probes were positioned on either of the anterior tibial muscles. rSO2 was measured continuously during balloon occlusion/deflation. A cycle consisted of inflating the aortic balloon for 30 min and deflating it for 5 min. The rSO2 before/during balloon occlusion and after 5 min of balloon deflation were evaluated. Sixty-two lower limbs (fifteen women and data from 31 sessions of balloon inflation/deflation) were evaluated. rSO2 during balloon occlusion was significantly lower than rSO2 before balloon occlusion (57.9% ± 9.6% vs. 80.3% ± 6.0%; p < 0.01). There were no significant differences between rSO2 before balloon occlusion and rSO2 after 5 min of balloon deflation (80.3% ± 6.0% vs. 78.7% ± 6.6%; p = 0.07). Postoperatively, the lower limbs showed no ischemic symptoms. NIRS can assess lower-limb rSO2 during PBOA for PAS in real time to determine ischemia severity, duration, and recovery capacity.

Placenta Accreta Spectrum and Postpartum Hemorrhage

Placenta accreta spectrum is a group of disorders involving abnormal trophoblastic invasion to the deep layers of endometrium and myometrium. Placenta accrete spectrum is one of the major causes of severe maternal morbidity, with increasing incidence in the past decade mainly secondary to an increase in cesarean deliveries. Severity varies depending on the depth of invasion, with the most severe form, known as percreta, invading uterine serosa or surrounding pelvic organs. Diagnosis is usually achieved by ultrasound, and MRI is sometimes used to assess invasion. Management usually involves a hysterectomy at the time of delivery. Other strategies include delayed hysterectomy or expectant management.

Obstetric admission to intensive care units in Japan: a cohort study using the Japanese Intensive care PAtient Database

PURPOSE

This study aimed to describe the epidemiology and annual trends of obstetric patients using a multicenter intensive care database.

METHODS

This multicenter, retrospective cohort study used the Japanese Intensive care PAtient Database (JIPAD). We included obstetric patients registered in the JIPAD between 2015 and 2020. We investigated the proportion of obstetric patients among all patients in the intensive care unit (ICU). We also described the characteristics, procedures, and outcomes of obstetric patients. In addition, the annual trends were examined by nonparametric tests for trends.

RESULTS

Of the 184,705 patients enrolled in the JIPAD, 750 (0.41%) were obstetric patients from 61 facilities. The median age was 34 years, the number of post-emergency surgeries was 450 (60.0%), and the median APACHE III score was 36. Mechanical ventilation was the most common procedure performed in 247 (32.9%) patients. There were five (0.7%) in-hospital deaths. The proportion of obstetric patients in the ICU did not change between 2015 and 2020 (P for trend = 0.32). However, there was a trend for a significant decrease in the severity of illness and length of hospital stay on an annual basis between 2015 and 2020. Most patients were admitted to the ICU because of a pregnancy-related disorder postoperatively.

CONCLUSION

The proportion of obstetric patients was 0.41% of all ICU admissions. The proportion of obstetric patients admitted to the ICU did not change from 2015 to 2020, but the patients' severity of illness and length of hospital stay significantly decreased over time.

Feasibility Study of Ferumoxtyol for Contrast-enhanced MRI of Retroplacental Clear Space Disruption in Placenta Accreta Spectrum (PAS)

Introduction

Placenta accreta spectrum (PAS) occurs when the placenta is pathologically adherent to the myometrium. An intact retroplacental clear space (RPCS) is a marker of normal placentation, but visualization with conventional imaging techniques is a challenge. In this study, we investigate use of an FDA-approved iron oxide nanoparticle, ferumoxytol, for contrast-enhanced magnetic resonance imaging of the RPCS in mouse models of normal pregnancy and PAS. We then demonstrate the translational potential of this technique in human patients presenting with severe PAS (FIGO Grade 3C), moderate PAS (FIGO Grade 1), and no PAS.

Methods

A T1-weighted gradient recalled echo (GRE) sequence was used to determine the optimal dose of ferumoxytol in pregnant mice. Pregnant Gab3 -/- mice, which demonstrate placental invasion, were then imaged at day 16 of gestation alongside wild-type (WT) pregnant mice which do not demonstrate invasion. Signal-to-noise ratio (SNR) was computed for placenta and RPCS for all fetoplacental units (FPUs) with ferumoxytol-enhanced magnetic resonance imaging (Fe-MRI) and used for the determination of contrast-to-noise ratio (CNR). Fe-MRI was also performed in 3 pregnant subjects using standard T1 and T2 weighted sequences and a 3D magnetic resonance angiography (MRA) sequence. RPCS volume and relative signal were calculated in all three subjects.

Results

Ferumoxytol administered at 5 mg/kg produced strong T1 shortening in blood and led to strong placental enhancement in Fe-MRI images. Gab3 -/- mice demonstrated loss of hypointense region characteristic of the RPCS relative to WT mice in T1w Fe-MRI. CNR between RPCS and placenta was lower in FPUs of Gab3 -/- mice compared to WT mice, indicating higher degrees of vascularization and interruptions throughout the space. In human patients, Fe-MRI at a dose of 5 mg/kg enabled high uteroplacental vasculature signal and quantification of the volume and signal profile in severe and moderate invasion of the placenta relative to a non-PAS case.

Discussion

Ferumoxytol, an FDA-approved iron oxide nanoparticle formulation, enabled visualization of abnormal vascularization and loss of uteroplacental interface in a murine model of PAS. The potential of this non-invasive visualization technique was then further demonstrated in human subjects. Diagnosis of placental invasion using Fe-MRI may provide a sensitive method for clinical detection of PAS.

A simple guide to ultrasound screening for placenta accreta spectrum for improving detection and optimizing management in resource limited settings

Placenta accreta spectrum is a pregnancy complication associated with severe morbidity and maternal mortality especially when not suspected antenatally and appropriate management instigated. Women in resource-limited settings are more likely to face adverse outcomes due to logistic, technical, and resource inadequacies. Accurate prenatal imaging is an important step in ensuring good outcomes because it allows adequate preparation and an appropriate management approach. This article provides a simple three-step approach aimed at guiding clinicians and sonographers with minimal experience in placental accreta spectrum through risk stratification and basic prenatal screening for this condition both with and without Doppler ultrasound.

The use of the double uterine segment tourniquet in obstetric hysterectomy for bleeding control in patients with placenta accreta spectrum

OBJECTIVES

To evaluate surgical outcomes of using a double uterine segment tourniquet in obstetric hysterectomy for bleeding control in patients with placenta accreta spectrum.

METHODS

Retrospective case-control study conducted at the Central Hospital of San Luis Potosi, Mexico. Patients with the diagnosis of placenta accreta spectrum who underwent obstetric hysterectomy were included. Two groups were formed: in the first, a double uterine segment tourniquet was used; and in the second, the hysterectomy was performed without a tourniquet. Primary surgical outcomes were compared.

RESULTS

Forty patients in each group were included. The use of a double uterine segment tourniquet had lower total blood loss compared with the non-tourniquet group (1054.00 ± 467.02 vs. 1528.75 ± 347.12 mL, P = 0.0171) and a lower drop in hemoglobin (1.74 ± 1.10 vs. 2.60 ± 1.25 mg/dL, P = 0.0486). Ten patients (23.80%) in the double tourniquet group required blood transfusion, compared with 26 (65.00%) in the non-tourniquet group (P = 0.0003). Surgical time did not show a statistical difference between groups.

CONCLUSION

The use of a uterine segment tourniquet in obstetric hysterectomy may improve surgical outcomes in patients with placenta accreta spectrum with no difference in surgical time and urinary tract lesions.

Overexpressed LAMC2 promotes trophoblast over-invasion through the PI3K/Akt/MMP2/9 pathway in placenta accreta spectrum

BACKGROUND

Placenta accreta spectrum (PAS) is an ongoing major iatrogenic public health challenge with devastating obstetric complications, but its underlying molecular pathogenesis remains poorly illuminated. LAMC2 is reported to regulate tumor cells proliferation and invasion, yet has not been explored in placenta trophoblast cells. This study investigated LAMC2 expression and its contribution in the etiology of PAS.

METHODS

Quantitative polymerase chain reaction, western blot, and immunohistochemistry were performed to detect the expression of LAMC2 in placentas. Cell proliferation, invasion, migration, and apoptosis were monitored by CCK8 assay, wound healing assay, transwell invasion assay, and flow cytometry assay. Western blot was conducted to confirm the pertinent proteins level of PI3K/Akt/MMP2/9 pathway in HTR8/SVneo cells.

RESULTS

LAMC2 was predominantly expressed in placental villous syncytiotrophoblasts and cytotrophoblasts. LAMC2 mRNA and protein expression were substantially upregulated in placental tissues with PAS compared to those with pernicious placenta previa without PAS. LAMC2 overexpression eminently boosted HTR8/SVneo cells proliferation, invasion, and migration, but inhibited apoptosis, accompanied by elevated protein expression of MMP2, MMP9, and phosphorylated Akt (pAkt). Knockdown of LAMC2 yielded the converse results. Additionally, when treated with LY294002, the effects of LAMC2 overexpression on proliferation, migration, invasion, and apoptosis of HTR8/SVneo cells were abolished and concomitantly the elevated pAkt, MMP2, and MMP9 proteins induced by LAMC2 overexpression were eliminated.

CONCLUSION

Our study highlighted the involvement of LAMC2 in the pathogenesis of PAS by activating the PI3K/Akt/MMP2/9 signaling pathway to stimulate trophoblast over-invasion. These findings provide a new target for the diagnosis and disease stratification of PAS.

Systematic review and meta-analysis on placenta accreta spectrum disorders in twin pregnancies: risk factors, detection rate and histopathology

INTRODUCTION

The occurrence of PAS has been recently associated with the presence of twin pregnancy. Aim of this review is to report the risk factors, histopathological correlation, diagnostic accuracy of prenatal ultrasound and clinical outcome of twin pregnancies complicated by placenta accreta spectrum (PAS) disorders.

EVIDENCE ACQUISITION

PubMed, Embase, Cinahl, Clinical Trial.Gov and Google Scholar databases were searched. Inclusion criteria were studies on twin pregnancies complicated by PAS. The outcomes explored were risk factors for PAS (including placenta previa, prior uterine surgery or assisted reproductive technology, ART), histopathology (placenta accreta and increta/percreta), detection rate of prenatal ultrasound and clinical outcome, including need for blood transfusion, hysterectomy, emergency or scheduled Cesarean delivery (CD), and maternal death. Random effect meta-analyses of proportions were sued to combine the data.

EVIDENCE SYNTHESIS

Two studies considering 103 pregnancies were included in this systematic review: 41.86% (95% CI 27.0-57.9) of twin pregnancies complicated by PAS disorders had a prior CD, 28.22% (95% CI 13.4-46.0) presented placenta previa and 58.14% (95% CI 42.1-73.0) of twin pregnancies were conceived by ART. 74.49% (95% CI 41.6-96.5) of PAS in twin pregnancies were placenta accreta, while 25.51% (95% CI 3.5-58.4) were placenta increta or percreta. Prenatal diagnosis of PAS in twin pregnancies was accomplished only in 27.91% (95% CI 15.3-43.7) of cases. Finally, only one study consistently reported the clinical outcome of PAS in twins. 31.67% (95% CI 20.3-45.0) of women required blood transfusion, 26.67% (95% CI 16.1-39.7) had hysterectomy, while there was no case of maternal death. 44.19% of women had an emergency CD.

CONCLUSIONS

There is still limited evidence on the clinical course of PAS disorders in twin pregnancies. Placenta previa, prior uterine surgery (mainly CD), and ART are the most commonly risk factors for PAS disorders in twins. Prenatal diagnosis of PAS in twins is lower compared to what reported in singleton. Finally, about 30% of women with a twin pregnancy complicated by PAS required blood transfusion and hysterectomy.

Emergency Obstetric Hysterectomy after Conservative Management of Placenta Accreta

Background

Obstetric hemorrhage is a frequent and life-threatening complication of either vaginal or cesarean delivery. It can be due to many causes, one of which is placenta accreta, the abnormal invasion of the placenta into the myometrial wall of uterus. Ultrasonography is the first line diagnostic method that can lead to the diagnosis of placenta accreta although, the depth of penetration is estimated by magnetic resonance imaging. Placenta accreta is a life-threatening situation requiring an experienced health care team for its management. Hysterectomy is usually performed although, conservative management might be preferred in carefully selected cases. Case Presentation. A 32-year-old woman (G2, P0) who had an inconsistently monitored pregnancy appeared at a regional hospital with contractions at 39th week of gestation. In her first pregnancy, she was subjected to cesarean section due to delay in second stage of labor and unfortunately her child died due to sudden cardiac death. During C-section, placenta accreta was identified. Given her previous history and her desire to maintain fertility, conservative management was initially planned to preserve her uterus. However, due to persisting vaginal bleeding immediately after delivery an emergency hysterectomy was performed.

Conclusion

Conservative management of placenta accreta can be considered in some special cases with the aim to spare fertility. However, if bleeding cannot be controlled during the immediate postpartum period, emergency hysterectomy is unavoidable. A specialized multidisciplinary medical team is required to optimize management.