Placenta accreta

Neonatal outcomes in pregnancies complicated by placenta accreta- a matched cohort study

PURPOSE

Pregnancies complicated by placenta accreta spectrum (PAS) are associated with severe maternal morbidities. The aim of this study is to describe the neonatal outcomes in pregnancies complicated with PAS compared with pregnancies not complicated by PAS.

METHODS

A retrospective cohort study conducted at a single tertiary center between 03/2011 and 01/2022, comparing women with PAS who underwent cesarean delivery (CD) to a matched control group of women without PAS who underwent CD. We evaluated the following adverse neonatal outcomes: umbilical artery pH < 7.0, umbilical artery base excess ≤ - 12, APGAR score < 7 at 5 min, neonatal intensive care unit (NICU) admission, mechanical ventilation, hypoxic ischemic encephalopathy, seizures and neonatal death. We also evaluated a composite adverse neonatal outcome, defined as the occurrence of at least one of the adverse neonatal outcomes described above. Multivariable regression analysis was used to determine which adverse neonatal outcome were independently associated with the presence of PAS.

RESULTS

265 women with PAS were included in the study group and were matched to 1382 controls. In the PAS group compared with controls, the rate of composite adverse neonatal outcomes was significantly higher (33.6% vs. 18.7%, respectively, p < 0.001). In a multivariable logistic regression analysis, Apgar score < 7 at 5 min, NICU admission and composite adverse neonatal outcome were independently associated with PAS.

CONCLUSION

Neonates in PAS pregnancies had higher rates of adverse outcomes. Apgar score < 7 at 5 min, NICU admission and composite adverse neonatal outcome were independently associated with 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..

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

OBJECTIVE

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

STUDY DESIGN

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

RESULTS

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

CONCLUSION

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

KEY POINTS

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

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

BACKGROUND

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

OBJECTIVES

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

SEARCH STRATEGY

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

CONCLUSION

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

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.

Prophylactic common iliac artery temporary clamping versus balloon occlusion for management of placenta accreta spectrum disorders: A prospective clinical trial

OBJECTIVE

The present study aims to compare prophylactic common iliac artery (CIA) temporary clamping and preoperative balloon occlusion for managing placenta accreta spectrum (PAS) disorders.

STUDY DESIGN

Between January 2019 and June 2020, 46 patients with PAS disorders were included. Of them, 26 patients were offered CIA balloon occlusion (Group A), while temporary CIA clamping was done for the other 20 patients (Group B). Primary outcomes were procedure-related complications, and secondary outcomes included intraoperative and postoperative complications, reoperation rates, total procedure time, blood loss, and amount of blood transfusion.

RESULTS

Blood loss was statistically non-significant higher in group B than in group A (p-value = 0.143). Only one patient in group A and three in group B needed reoperation. The bleeding continued for a mean of 1.6 days in group A and 1.7 days in group B, with non-significant statistical differences between both groups p value = 0.71. Nine patients in group A (34.6%) and four in group B (20%) required ICU admission. The mean Apgar score was 7 and 6.6 in babies of group A and group B patients, respectively. The median number of allogeneic blood transfusions performed was two in patients in group A and 1 in group B (p-value = 0.001).

CONCLUSION

Both techniques offer good choices for patients with PAS to decrease mortality and morbidity rates. The selection of a better technique depends on institutional references and physicians' experience.

Material properties of nonpregnant and pregnant human uterine layers

The uterus has critical biomechanical functions in pregnancy and undergoes dramatic material growth and remodeling from implantation to parturition. The intrinsic material properties of the human uterus and how they evolve in pregnancy are poorly understood. To address this knowledge gap and assess the heterogeneity of these tissues, the time-dependent material properties of all human uterine layers were measured with nanoindentation. The endometrium-decidua layer was found to be the least stiff, most viscous, and least permeable layer of the human uterus in nonpregnant and third-trimester pregnant tissues. In pregnancy, the endometrium-decidua becomes stiffer and less viscous with no material property changes observed in the myometrium or perimetrium. Additionally, uterine material properties did not significantly differ between third-trimester pregnant tissues with and without placenta accreta. The foundational data generated by this study will facilitate the development of physiologically accurate models of the human uterus to investigate gynecologic and obstetric disorders.

CT angiography for characterization of advanced placenta accreta spectrum: indications, risks, and benefits

Placenta accreta spectrum disorder (PASD) encompasses various types of abnormal placentation in which chorionic villi directly adhere to or invade the myometrium. The incidence of PASD has dramatically risen in the US over the past 3 decades owing to the increased rates of patients undergoing cesarean sections. While PASD remains a significant cause of maternal morbidity and mortality, accurate prenatal identification and characterization of PASD is associated with improved outcomes. Although ultrasound is the first-line imaging modality in the evaluation of PASD, with MRI serving as an adjunct, computed tomography angiography (CTA) may also offer unique diagnostic advantages in cases of advanced PASD by providing superior visualization of placental and abdominopelvic vasculature and enabling the creation of comprehensive vascular maps to roadmap complex surgical interventions. This paper represents the first evaluation of CTA as a diagnostic tool and operative planning aid in this context. Appropriate indications and diagnostic advantages of CTA in this setting are reviewed, and key multimodal imaging features of normal and abnormal placentation are highlighted.

Placenta accreta spectrum care infrastructure: an evidence-based review of needed resources supporting placenta accreta spectrum care

The incidence of placenta accreta spectrum, the deeply adherent placenta with associated increased risk of maternal morbidity and mortality, has seen a significant rise in recent years. Therefore, there has been a rise in clinical and research focus on this complex diagnosis. There is international consensus that a multidisciplinary coordinated approach optimizes outcomes. The composition of the team will vary from center to center; however, central themes of complex surgical experts, specialists in prenatal diagnosis, critical care specialists, neonatology specialists, obstetrics anesthesiology specialists, blood bank specialists, and dedicated mental health experts are universal throughout. Regionalization of care is a growing trend for complex medical needs, but the location of care alone is just a starting point. The goal of this article is to provide an evidence-based framework for the crucial infrastructure needed to address the unique antepartum, delivery, and postpartum needs of the patient with placenta accreta spectrum. Rather than a clinical checklist, we describe the personnel, clinical unit characteristics, and breadth of contributing clinical roles that make up a team. Screening protocols, diagnostic imaging, surgical and potential need for critical care, and trauma-informed interaction are the basis for comprehensive care. The vision from the author group is that this publication provides a semblance of infrastructure standardization as a means to ensure proper preparation and readiness.

Material Properties of Nonpregnant and Pregnant Human Uterine Layers

The uterus has critical biomechanical functions in pregnancy and undergoes dramatic material growth and remodeling from implantation to parturition. The intrinsic material properties of the human uterus and how they evolve in pregnancy are poorly understood. To address this knowledge gap and assess the heterogeneity of these tissues, the time-dependent material properties of all human uterine layers were measured with nanoindentation. The endometrium-decidua layer was found to be the least stiff, most viscous, and least permeable layer of the human uterus in nonpregnant and third-trimester pregnant tissues. In pregnancy, endometrium-decidua becomes stiffer and less viscous with no material property changes observed in the myometrium or perimetrium. Additionally, uterine material properties did not significantly differ between third-trimester pregnant tissues with and without placenta accreta. The foundational data generated by this study will facilitate the development of physiologically accurate models of the human uterus to investigate gynecologic and obstetric disorders.

Prophylactic radiologic interventions to reduce postpartum hemorrhage in women with risk factors for placenta accreta spectrum disorder: a nationwide cohort study

OBJECTIVE

To quantify the association between prophylactic radiologic interventions and perioperative blood loss in women with risk factors for placenta accreta spectrum disorder (PAS).

METHODS

We conducted a retrospective nationwide cohort study of women with risk factors for placenta accreta spectrum disorder who underwent planned cesarean section in 69 Dutch hospitals between 2008 and 2013. All women had two risk factors for PAS: placenta previa/anterior low-lying placenta and a history of cesarean section(s). Women with and without ultrasonographic signs of PAS were studied as two separate groups. We compared the total blood loss of women with prophylactic radiologic interventions, defined as preoperative placement of balloon catheters or sheaths in the internal iliac or uterine arteries, with that of a control group consisting of women without prophylactic radiologic interventions using multivariable regression. We evaluated maternal morbidity by the number of red blood cell (RBC) units transfused within 24 h following childbirth (categories: 0, 1-3, >4), duration of hospital admission, and need for intensive care unit (ICU) admission.

RESULTS

A total of 350 women with placenta previa/anterior low-lying placenta and history of cesarean section(s) were included: 289 with normal ultrasonography, of whom 21 received prophylactic radiologic intervention, and 61 had abnormal ultrasonography, of whom 22 received prophylactic intervention. Among women with normal ultrasonography without prophylactic intervention (n = 268), the median blood loss was 725 mL (interquartile range (IQR) 500-1500) vs. 1000 mL (IQR 550-1750) in women with intervention (n = 21); the adjusted difference in blood loss was 9 mL (95% confidence interval (CI) -315-513), p = .97). Among women with abnormal ultrasonography, those without prophylactic intervention (n = 39) had a median blood loss of 2500 mL (IQR 1200-5000) vs. 1750 mL (IQR 775-4000) in women with intervention (n = 22); the adjusted difference in blood loss was -1141 mL (95% CI -1694- -219, p = .02). Results of outcomes on maternal morbidity were comparable among women with and without prophylactic intervention.

CONCLUSION

These findings suggest that prophylactic radiologic interventions prior to planned cesarean section may help to limit perioperative blood loss in women with clear signs of placenta accreta spectrum disorder on ultrasonography, but there was no evidence of a difference within the subgroup without such ultrasonographic signs. The use of these interventions should be discussed in a multidisciplinary shared decision-making process, including discussions of potential benefits and possible complications.

TRIAL REGISTRATION

Netherlands Trial Registry, https://onderzoekmetmensen.nl/en/trial/28238, identifier NL4210 (NTR4363).

The Association of Serum Midkine Level with Invasion in Placenta Previa: A Case-Control Study from a Tertiary Reference Center

We aimed to examine the relationship between serum midkine levels and placental invasion in pregnant women with placenta previa. The study group consisted of 43 pregnant women diagnosed with placenta previa, whereas the control group consisted of 60 healthy pregnant women. Serum midkine levels were compared between pregnant women with placenta previa and the control group in this study's first part. Thereafter, the utility of midkine in the prediction of the abnormally invasive placenta (AIP) was investigated and optimal cutoff values were calculated. Significantly higher serum midkine level was observed in placenta previa cases than in the controls (1.16 ng/mL vs. 0.18 ng/mL, P < 0.001). Serum midkine level was also significantly higher in the AIP group among the placenta previa cases (P = 0.004). In the receiver operating characteristic analysis, the cutoff value of the midkine level in predicting AIP was 1.19 ng/mL. This study revealed that the serum midkine level is higher in pregnant women with AIP. Maternal serum midkine level may be used as a complementary biomarker to the radiological and clinical findings for the prediction of the AIP in placenta previa cases.

Placenta accreta spectrum in early and late pregnancy from an imaging perspective. A scoping review

Placenta accreta spectrum (PAS) disorders (with increasing order of the depth of invasion: accreta, increta, percreta) are quite challenging for the purpose of diagnosis and treatment. Pathological examination or imaging evaluation are not very dependable when considered as stand-alone diagnostic tools. On the other hand, timely diagnosis is of great importance, as maternal and fetal mortality drastically increases if patient goes through the third phase of delivery in a not well-suited facility. A multidisciplinary approach for diagnosis (incorporating clinical, imaging, and pathological evaluation) is mandatory, particularly in complicated cases. For imaging evaluation, the diagnostic modality of choice in most scenarios is ultrasound (US) exam; patients are referred for MRI when US is equivocal, inconclusive, or not visualizing placenta properly. Herewith, we review the reported US and MRI features of PAS disorders (mainly focusing on MRI), going over the normal placental imaging and imaging pitfalls in each section, and lastly, covering the imaging findings of PAS disorders in the first trimester and cesarean section pregnancy (CSP).

Prophylactic ureteral stent placement for the prevention of genitourinary tract injury during hysterectomy for placenta accreta spectrum: systematic review and meta-analysis

OBJECTIVE

This study aimed to assess the effectiveness of prophylactic ureteral stent placement for the prevention of genitourinary tract injury at the time of cesarean hysterectomy for placenta accreta spectrum. The secondary objectives were to assess mean blood loss, operative time, number of packed red blood cells transfused, and rates of urinary tract infection among patients undergoing cesarean hysterectomy for placenta accreta spectrum with and without prophylactic ureteral stent placement.

DATA SOURCES

The search was performed using PubMed, Cochrane Library, and ClinicalTrials.gov from inception to February 2022 to December 2022. The protocol for this review was registered with the International Prospective Register of Systematic Reviews before data collection (registration number: CRD42022372817).

STUDY ELIGIBILITY CRITERIA

All studies that examined differences in the rate of genitourinary tract injury among women undergoing cesarean hysterectomy for prenatally suspected placenta accreta spectrum with and without placement of prophylactic ureteral stents were included. Genitourinary injury was defined as cystotomy, ureteral injury, and/or bladder fistula. Cases of both intentional and unintentional genitourinary injuries were included in the analysis.

METHODS

For all studies meeting the inclusion criteria, the following data were extracted: number of included patients, maternal demographic information, obstetrical history, type of invasive placentation, placement of stents (yes or no), type of stent placed, blood loss, operative time, genitourinary tract injury, and urinary tract infection. Pooled data analysis was completed using the Review Manager (version 5.3; Nordic Cochrane Centre, Copenhagen, Denmark; Cochrane Collaboration, 2014). The summary measures were reported as summary relative risk or as summary mean difference. The quality and risk of biases of the included studies were assessed according to the Newcastle-Ottawa Scale.

RESULTS

Overall, 9 studies, including 848 patients, fulfilled our inclusion criteria and were included in our analysis. Moreover, 523 patients (61.7%) had prophylactic ureteral stents placed, and 325 patients (38.3%) did not. Genitourinary injury occurred in 138 of 523 patients (26.4%) in the ureteral stent group vs 83 of 325 patients (25.5%) in the no ureteral stent group (relative risk, 0.94; 95% confidence interval, 0.74-1.20). The mean number of packed red blood cells transfused did not differ between the 2 groups. The pooled analysis demonstrated decreased blood loss among patients who received prophylactic ureteral stents, with a mean difference of 392 mL (95% confidence interval, 52.74-738.13).

CONCLUSION

Our systematic review and meta-analysis demonstrated no difference in the rates of genitourinary tract injury with the use of prophylactic ureteral stent placement among cases of prenatally suspected placenta accreta spectrum undergoing cesarean hysterectomy.

Delayed presentation of placenta accreta following a first-trimester medical abortion

Placenta accreta can rarely present as a uterine mass on imaging months after a first trimester medical abortion, even in patients at low-risk for abnormal placentation. Early and accurate diagnosis can be crucial to reduce morbidity and mortality associated with this disease, particularly for those desiring fertility preservation.

Uterus-preserving surgical management of placenta accreta spectrum disorder: a large retrospective study

BACKGROUND

The two-child policy implemented in China resulted in a surge of high-risk pregnancies among advanced maternal aged women and presented a window of opportunity to identify a large number of placenta accreta spectrum (PAS) cases, which often invoke severe blood loss and hysterectomy. We thus had an opportunity to evaluate the surgical outcomes of a unique conservative PAS management strategy for uterus preservation, and the impacts of magnetic resonance imaging (MRI) in PAS surgical planning.

METHODS

Cross-sectional study, comparing the outcomes of a new uterine artery ligation combined with clover suturing technique (UAL + CST) with the existing conservative surgical approaches in a maternal public hospital with an annual birth of more than 20,000 neonates among all placenta previa cases suspecting of PAS between January 1, 2015 and December 31, 2018.

RESULTS

From a total of 89,397 live births, we identified 210 PAS cases from 400 singleton pregnancies with placenta previa. Aside from 2 self-requested natural births (low-lying placenta), all PAS cases had safe cesarean deliveries without any total hysterectomy. Compared with the existing approaches, the evaluated UAL + CST had a significant reduction in intraoperative blood loss (β=-312 ml, P < .001), RBC transfusion (β=-1.08 unit, P = .001), but required more surgery time (β = 16.43 min, P = .01). MRI-measured placenta thickness, when above 50 mm, can increase blood loss (β = 315 ml, P = .01), RBC transfusion (β = 1.28 unit, P = .01), surgery time (β = 48.84 min, P < .001) and hospital stay (β = 2.58 day, P < .001). A majority of percreta patients resumed normal menstrual cycle within 12 months with normal menstrual fluid volume, without abnormal urination or defecation.

CONCLUSIONS

A conservative surgical management approach of UAL + CST for PAS is safe and effective with a low complication rate. MRI might be useful for planning PAS surgery.

CLINICAL TRIAL REGISTRATION NUMBER

ChiCTR2000035202.

Critical Care in Placenta Accreta Spectrum Disorders-A Call to Action

The rising in placenta accreta spectrum (PAS) incidence, highlights the need for critical care allotment for these patients. Due to risk for hemorrhage and possible hemorrhagic shock requiring blood product transfusion, hemodynamic instability and risk of end-organ damage, having an intensive care unit (ICU) with surgical expertise (surgical ICU or equivalent based on institutional resources) is highly recommended. Intensive care units physicians and nurses should be familiarized with intraoperative anesthetic and surgical techniques as well as obstetrics physiologic changes to provide postpartum management of PAS. Validated tools such of bedside point of care ultrasound and viscoelastic tests such as thromboelastogram/rotational thromboelastometry (TEG/ROTEM) are clinically useful in the assessment of hemodynamic status (shock diagnosis, assessment of both fluid responsiveness and tolerance) and transfusion guidance (in patients requiring massive transfusion as opposed to tranditional hemostatic resuscitation) respectively. The future of PAS management lies in the collaborative and multidisciplinary environment. We recommend that women with high suspicion or a confirmed PAS should have a preoperative plan in place and be managed in a tertiary center who is experienced in managing surgically complex cases. KEY POINTS: · The rising in placenta accreta spectrum incidence highlights the need for critical care expertise.. · Emerging tools such as point-of-care ultrasound and thromboelastography/rotational thromboelastometry represent new avenues for real time optimization of hemodynamic and hematological care of patients with PAS.. · Patients with PAS should be referred to a tertiary center having an intensive care unit (ICU) with surgical expertise (or equivalent based on institutional resources)..

Urinary tract injuries during surgery for placenta accreta spectrum disorders

OBJECTIVE

The main purpose of this study was to report the incidence of lower urinary tract injuries (UTI) during cesarean section (CS) hysterectomy in cases of Placenta Accreta Spectrum (PAS) disorders. Study design Retrospective analysis including all women with a prenatal diagnosis of PAS between January 2010 and December 2020. A dedicated multidisciplinary team was involved to define a tailored management for each patient. All relevant demographic parameters, risk factors, degree of placental adhesion, type of surgery, complications and operative outcomes were reported.

RESULTS

One hundred and fifty-six singleton gestations with a prenatal diagnosis PAS were included in the analysis. 32.7% of cases were classified as PAS 1 (grade 1-3a FIGO classification), 20.5% as PAS 2 (grade 3b FIGO classification) and 46.8% as PAS 3 (grade 3c FIGO classification). A CS hysterectomy was performed in all cases. Surgical complication occurred in seventeen cases (0% in PAS 1, 12.5% in PAS 2 cases and in 17.8% in PAS 3). The incidence of UTI in our series was 7.6% in all women with PAS, including 8 cases of bladder and 12 of ureteral lesion, and 13.7 % in those with PAS 3 only.

CONCLUSION

Despite advances in prenatal diagnosis and management, surgical complications, mainly those involving the urinary system, still occur in a significant proportion of women undergoing surgery for PAS. The findings from this study highlight the need for a multidisciplinary management of women with PAS in centers with high expertise in prenatal diagnosis and surgical management of these conditions.

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 evolution of the labor curve and its implications for clinical practice: the relationship between cervical dilation, station, and time during labor

The assessment of labor progress is germane to every woman in labor. Two labor disorders-arrest of dilation and arrest of descent-are the primary indications for surgery in close to 50% of all intrapartum cesarean deliveries and are often contributing indications for cesarean deliveries for fetal heart rate abnormalities. Beginning in 1954, the assessment of labor progress was transformed by Friedman. He published a series of seminal works describing the relationship between cervical dilation, station of the presenting part, and time. He proposed nomenclature for the classification of labor disorders. Generations of obstetricians used this terminology and normal labor curves to determine expected rates of dilation and fetal descent and to decide when intervention was required. The analysis of labor progress presents many mathematical challenges. Clinical measurements of dilation and station are imprecise and prone to variation, especially for inexperienced observers. Many interrelated factors influence how the cervix dilates and how the fetus descends. There is substantial variability in when data collection begins and in the frequency of examinations. Statistical methods to account for these issues have advanced considerably in recent decades. In parallel, there is growing recognition among clinicians of the limitations of using time alone to assess progress in cervical dilation in labor. There is wide variation in the patterns of dilation over time and most labors do not follow an average dilation curve. Reliable assessment of labor progression is important because uncertainty leads to both over-use and under-use of cesarean delivery and neither of these extremes are desirable. This review traces the evolution of labor curves, describes how limitations are being addressed to reduce uncertainty and to improve the assessment of labor progression using modern statistical techniques and multi-dimensional data, and discusses the implications for obstetrical practice.

Abnormal placenta implantation. Integration between first- and third-trimester imaging in predicting the severity of Placenta Accreta Spectrum (PAS) disorders

Placenta accreta spectrum (PAS) disorders are pathological conditions correlated to a high risk of adverse maternal surgical outcomes, especially if not diagnosed. In the last 10 years, the literature interest for prenatal diagnosis of PAS disorders has been noticeably greater. More recently, significant progression in prenatal imaging techniques permitted an increase of early identified cases and a more accurate diagnosis of these anomalies, especially in women with multiple risk factors. The aim of this chapter is to give an overhaul on prenatal diagnosis of PAS disorders throughout gestation and to report whether integration between first- and third-trimester ultrasound can predict the development and severity of these anomalies.

Ultrasonographic Prediction of Placental Invasion in Placenta Previa by Placenta Accreta Index

This study aimed to investigate the diagnostic accuracy of the placenta accreta index (PAI) for predicting placenta accreta spectrum (PAS) in women with placenta previa. We analyzed 33 pregnancies with placenta previa at Keio University Hospital. The PAI was assessed in the early third trimester, and PAS was diagnosed histologically or clinically defined as retained placenta after manual removal attempts. The PAI and incidence of PAS were analyzed. Ten women (30%) were diagnosed with PAS and had higher volumes of perioperative bleeding (p = 0.016), higher rate of requiring uterine artery embolization (p = 0.005), and peripartum hysterectomy (p = 0.0002) than women without PAS. A PAI > 2 was the most useful cut-off point for predicting PAS and was more sensitive than prediction values using traditional evaluation (history of cesarean section and placental location). Post-hoc analysis revealed a higher rate of previous history of cesarean delivery (30% vs. 4.4%, p = 0.038), severe placental lacunae (≥grade2) (70% vs. 8.7%, p = 0.0003), thin myometrial thickness (90% vs. 22%, p = 0.0003), anterior placenta (100% vs. 30%, p = 0.0002), and presence of bridging vessels (30% vs. 0%, p = 0.0059) in PAS women. PAI could help predict the outcomes of women with placenta previa with and without a history of cesarean delivery to reduce PAS-induced perinatal complications.

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.

Correlation of placental thickness and placenta percreta in patients with placenta previa: findings from MRI

INTRODUCTION

This study aimed to identify if placental thickness measured from MRI images correlated with placenta percreta in patients with placenta previa.

METHODS

Placental thickness was retrospectively measured in 161 patients from July 2018 to August 2020. The measurements were performed at the thickest part of the placenta in the lower uterine segment on the mid-sagittal plane MR images by two independent radiologists. Intraoperative and pathologic findings were the standard of reference. Univariate and multivariate analyses were performed to identify the relationship between clinical features, placental thickness, and placenta percreta. The predictive ability of placental thickness was demonstrated using receiver operating characteristic curve analysis.

RESULTS

Placental thickness in patients with placenta percreta was significantly higher than in patients with placenta increta, placenta accreta, and normal placentas (p < 0.05). Multivariate analysis revealed that placental thickness was the only independent risk factor for placenta percreta. The cutoff value of placental thickness was 4.35 cm for differentiating placenta percreta in patients with placenta previa.

DISCUSSION

Patients with placenta percreta had the highest placental thickness. Placental thickness was correlated with placenta percreta.

Expected Versus Unexpected Delivery for Placenta Accreta Spectrum (PAS) Disorders with Same Team in Single Tertiary Center

OBJECTIVES

To evaluate the maternal and neonatal outcomes of expected and unexpected pathologically proven placenta accreta spectrum (PAS) cases in a single multidisciplinary center.

MATERIAL AND METHODS

This was a retrospective cohort study of 92 PAS cases from January 2011 until September 2021. Only cases with histopathologically invasive placentation were included in the study. The cases diagnosed at the time of delivery were defined as unexpected PAS (uPAS) and those diagnosed antenatally as expected PAS (ePAS). Maternal and neonatal outcomes of both groups were compared.

RESULTS

Thirty-five (38%) of 92 cases were in the uPAS group. Placenta previa and high-grade PAS (percreata) were significantly higher in the ePAS group (p=0.028, p<0.001; respectively). The mean packed red blood cell transfusion was significantly higher in the uPAS group (p=0.030) but transfusions of other blood products were similar in the two groups. There was no significant difference in intraoperative complication rates between the two groups. Preterm delivery (<37 weeks) was significantly higher in the ePAS group (p<0.001), but there was no significant difference between the two groups in terms of adverse neonatal outcomes.

CONCLUSIONS

Our single center data show that although ePAS cases include more highly invasive PAS cases, maternal hemorrhagic morbidity is lower than uPAS cases. Reducing maternal morbidity in PAS cases can be achieved by increasing antenatal diagnosis.

Prophylactic Ureteral Stent Placement and Urinary Injury During Hysterectomy for Placenta Accreta Spectrum

OBJECTIVE

To evaluate the association between prophylactic ureteral stent placement at the time of hysterectomy for placenta accreta spectrum and genitourinary injury.

METHODS

We conducted a retrospective cohort study of patients with placenta accreta spectrum who underwent hysterectomy at two referral centers from 2001 to 2021. The exposure was prophylactic ureteral stent placement. The primary outcome, genitourinary injury, was a composite of bladder injury, ureteral injury, or vesicovaginal fistula. Secondary outcomes included components of the primary outcome. We evaluated differences between groups using χ 2 and t test. To evaluate differences in the primary outcome, we reported odds ratios (ORs) and adjusted odds ratios (aORs) using multivariable logistic regression analyses to control for potential confounding variables. We used a Cochran-Armitage χ 2 trend test to evaluate difference in stent use and injury over time.

RESULTS

In total, 236 patients were included. Prophylactic ureteral stents were used in 156 surgeries (66%). Overall, genitourinary injury occurred less frequently in the stent group compared with the no stent group (28% vs 51%, OR 0.37, 95% CI 0.21-0.65). This association persisted after controlling for urgency of delivery, three or more prior cesarean deliveries, and whether a gynecologic oncologist was present (aOR 0.27, 95% CI 0.14-0.52). Unintentional bladder injury occurred less frequently in the stent group compared with the no stent group (13% vs 25%, P =.018), as did ureteral injury (2% vs 9%, P =.019).

CONCLUSION

Prophylactic ureteral stent placement was associated with a decreased risk of genitourinary injury during hysterectomy for placenta accreta spectrum.

Long-term gynecological complications after conservative treatment of placenta accreta spectrum

Objective

To examine the association between conservative treatment for PAS (placenta accreta spectrum) and subsequent gynecological and fertility complications.

Methods

All women who underwent conservative treatment for PAS between January 1990 and December 2000 were included in this retrospective cohort study conducted in a tertiary teaching hospital. Gynecological and fertility complications experienced after the index delivery were collected from the medical records and telephone questionnaires. This data was compared to an age and parity-matched control group of women without PAS.

Results

The study group included 134 women with PAS managed conservatively and 134 controls with normal deliveries matched by parity and age. Women in the PAS group required significantly more postpartum operative procedures such as hysteroscopy or D&amp;C (OR = 6.6; 95%CI: 3.36–13.28; P = &lt;0.001). Following the index delivery, there were 345 pregnancies among 107 women who attempted conception following conservative treatment for PAS vs. 339 pregnancies among 105 women who attempted conception in the control group. Among women who attempted conception following conservative treatment for PAS 99 (92.5%) delivered live newborns (a total of 280 deliveries) vs. 94 (89.5%) in the control group, (a total of 270 live newborns, p = 0.21). The need for fertility treatments was not different between the two groups (OR = 1.22; 95%CI: 0.51–2.93; P = 0.66).

Conclusion

After conservative treatment for PAS, significantly more women required complementary procedures due to retained placenta and/or heavy vaginal bleeding. There was no evidence of fertility impairment in women post-conservative treatment for PAS.

Gynecologic oncologists in surgery for placenta accreta spectrum: a survey for practice, experience, and interest

OBJECTIVE

Surgery for placenta accreta spectrum is associated with significant maternal morbidity and mortality. The role of gynecologic oncologists in the surgical management of placenta accreta spectrum is currently under investigation. This study examined the practices, experiences, and interests of gynecologic oncologists in placenta accreta spectrum surgeries.

METHODS

The intervention was an anonymous, cross-sectional, 20-question survey sent to 1084 members of the Society of Gynecologic Oncology in the USA.

RESULTS

A total of 184 gynecologic oncologists responded to the survey (response rate 17.0%). Most participating gynecologic oncologists have been practicing for >10 years after fellowship (53.2%), practice in urban-teaching hospitals (84.8%) with delivery volumes ≥3000/year (54.3%), and have a multidisciplinary approach (82.5%). Three-quarters (78.7%) feel that the rate of placenta accreta spectrum is increasing over time. One-third (35.5%) perform ≥6 hysterectomies for placenta accreta spectrum yearly. Less than half (45.5%) practice conservative management. Approximately half are involved from the beginning of the case (49.7%) and perform the surgery in the main operating room (59.4%). Almost three-quarters (71.6%) have experienced surgical blood loss >5 L and one-third (36.6%) have experienced cases with blood loss >10 L. About half (50.3%) of participants are interested in placenta accreta spectrum surgery for future practice. Gynecologic oncologists engaging in a multidisciplinary approach are more likely to practice in an urban-teaching hospital, have higher surgical volume, be involved from the beginning of the case, and be interested in placenta accreta spectrum surgery. Those >10 years post-training and in the Southern US region are more likely to practice conservative management or delayed hysterectomy.

CONCLUSION

This society-based cross-sectional survey suggests that gynecologic oncologists are actively involved in the surgical management of placenta accreta spectrum in the USA. Nearly half of gynecologic oncologists who responded to the survey expressed interest in surgery for placenta accreta spectrum.

Symptoms of maternal psychological distress during pregnancy: sex-specific effects for neonatal morbidity

OBJECTIVES

Maternal psychological distress during pregnancy has been associated with preterm birth. However, little is known about the relationship of a woman's psychological symptoms during pregnancy to the infant's morbidity at birth or any differential effects of these symptoms on female vs. male fetuses. Our research aims addressed these gaps.

METHODS

A total of 186 women were enrolled between 24 and 34 weeks gestation when demographic information was acquired and they completed the Brief Symptom Inventory to measure psychological distress. Data on gestational age at birth, fetal sex, and neonatal morbidity was extracted from the medical record. To control for their effects, obstetric complications were also identified. Multiple linear regressions were computed to examine the aims, including interaction terms to measure moderating effects of fetal sex.

RESULTS

Symptoms of maternal psychological distress were a significant predictor of neonatal morbidity but were not associated with gestational age. The interaction between symptom distress and fetal/infant sex was also significant for neonatal morbidity but not for gestational age. For boys, high levels of maternal symptom distress during pregnancy were associated with neonatal resuscitation, ventilatory assistance, and infection. Maternal distress was not associated with neonatal morbidity for girls.

CONCLUSIONS

The male fetus may be more sensitive to effects of mothers' psychological symptoms than the female fetus. Further research is needed to confirm our findings and identify potential biological mechanisms that may be responsible for these sex differences. Findings suggest the importance of symptom screening and early intervention to reduce maternal distress and risk of neonatal morbidity.

Nanoparticle Contrast-enhanced MRI for Visualization of Retroplacental Clear Space Disruption in a Mouse Model of Placental Accreta Spectrum (PAS)

INTRODUCTION

Prior preclinical studies established the utility of liposomal nanoparticle blood-pool contrast agents in visualizing the retroplacental clear space (RPCS), a marker of normal placentation, while sparing fetuses from exposure because the agent does not cross the placental barrier. In this work, we characterized RPCS disruption in a mouse model of placenta accreta spectrum (PAS) using these agents.

MATERIALS AND METHODS

Contrast-enhanced MRI (CE-MRI) and computed tomography (CE-CT) using liposomal nanoparticles bearing gadolinium (liposomal-Gd) and iodine were performed in pregnant Gab3^-/- and wild type (WT) mice at day 16 of gestation. CE-MRI was performed on a 1T scanner using a 2D T1-weighted sequence (100×100×600 µm³ voxels) and CE-CT was performed at a higher resolution (70×70×70 µm³ voxels). Animals were euthanized post-imaging and feto-placental units (FPUs) were harvested for histological examination. RPCS conspicuity was scored through blinded assessment of images.

RESULTS

Pregnant Gab3^-/- mice showed elevated rates of complicated pregnancy. Contrast-enhanced imaging demonstrated frank infiltration of the RPCS of Gab3^-/- FPUs. RPCS in Gab3^-/- FPUs was smaller in volume, demonstrated a heterogeneous signal profile, and received lower conspicuity scores than WT FPUs. Histology confirmed in vivo findings and demonstrated staining consistent with a thinner RPCS in Gab3^-/- FPUs.

DISCUSSION

Imaging of the Gab3^-/- mouse model at late gestation with liposomal contrast agents enabled in vivo characterization of morphological differences in the RPCS that could cause the observed pregnancy complications. An MRI-based method for visualizing the RPCS would be valuable for early detection of invasive placentation.

The value of a simple sonographic screening test for placenta accreta spectrum prediction: A case-control study

BACKGROUND

Placenta accreta spectrum (PAS) represents life-threatening conditions; however, early diagnosis reduces complications and mortality rates.

AIMS

To develop and evaluate the accuracy of a simple sonographic screening test for PAS prediction.

MATERIALS AND METHODS

A retrospective case-control study of 481 women with singleton pregnancies at 28 weeks or later, with a scarred uterus or placenta praevia, who underwent sonographic testing for PAS detection during 2010-2020. We compared demographic and sonographic features, and delivery outcomes between women who were and were not confirmed to have a PAS condition at delivery. We evaluated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and predictive probability for the sonographic screening model.

RESULTS

Among all the women with at least one sonographic sign (large lacunae or loss of clear zone), the odds ratio (OR) of PAS was 21.7 (95% CI, 16.7-70.4), among those with placenta praevia (and at least one sonographic sign), the OR was 41.9 (95% CI, 15.8-111). For the screening model (the combinations of placental location (major or minor placenta praevia) with at least one sonographic sign (large lacunae or loss of clear zone)), sensitivity, specificity, PPV, NPV and predicted probability were 94.9% (85.8-98.9%), 91.5% (88.4-93.9%), 60.9% (50.1-70.9%), 99.2% (97.7-99.8%) and 92.3%, respectively.

CONCLUSIONS

A combination of simple ultrasound signs for PAS screening may be highly effective for prenatal assessment and prediction of placenta accreta. This screening test can be carried out as routine pregnancy follow-up for women with risk factors for PAS.

Placenta Accreta Spectrum: Prenatal Diagnosis and Management

The incidence of placenta accreta spectrum (PAS) is increasing and is now about 3 per 1000 deliveries, largely due to the rising cesarean section rate. Ultrasound is the preferred method for diagnosis of PAS. Ultrasound markers include multiple vascular lacunae, loss of the hypoechoic retroplacental zone, abnormalities of the uterine serosa-bladder interface, retroplacental myometrial thickness less than 1 mm, increased placental vascularity, and observation of bridging vessels linking the placenta and bladder. Patients with PAS should be managed by experienced multidisciplinary teams. Hysterectomy is the accepted management of PAS and conservative or expectant management of PAS should be considered investigational.

Pregnancy following cesarean scar defect (niche) repair: a cohort study

PURPOSE

The aim of the study is to learn the obstetrical outcome of women after laparoscopic niche repair.

METHODS

A retrospective cohort study including all women after laparoscopic niche repair done by a single high-skilled surgeon, from July 2014 to March 2019. Data were collected from women's medical records and a telephone interview was performed to assess further symptoms and attempts to conceive, including pregnancy outcomes.

RESULTS

During the study period, 48 women underwent laparoscopic niche repair, of them complete follow-up was achieved for 37 (78.7%) women. The median residual myometrial thickness measured by ultrasound before the repair was 2.0 mm (IQR 1.4-2.5). Attempts to conceive were reported by 81% (n = 30) of the women, while 18 (60%) achieved pregnancy in median time of 6 month (IQR 5-12) post-niche repair. 14 (78%) of the women conceived spontaneously. No placental abnormalities were reported in any of the women. All gave birth by cesarean delivery at a median of 38.4 gestation week (IQR 37.0-39.5). No dehiscence or rupture was reported.

CONCLUSIONS

Pregnancy following niche repair can be achieved with low pregnancy complication rate and good pregnancy outcomes. Further studies need to be done to strengthen our findings.

Percreta score to differentiate between placenta accreta and placenta percreta with ultrasound and MR imaging

INTRODUCTION

The objective of this study was to assess the performance of ultrasound and magnetic resonance imaging (MRI) features in helping to classify the type of placenta accreta spectrum (PAS; accreta/increta vs percreta), alone or combined in a predictive score.

MATERIAL AND METHODS

We conducted a retrospective study in 82 pregnant women with PAS who underwent ultrasound and MRI examination of the pelvis before delivery (from an initial cohort of 185 women with PAS). We estimated the sensitivity, specificity and accuracy of MRI and ultrasound in the diagnosis of the type of PAS. We analyzed cesarean and imaging features using univariable logistic regression analysis. We constructed a nomogram to predict the risk of placenta percreta and validated it with bootstrap resampling, then used receiver operating characteristic curves to assess the performance of the model in distinguishing between placenta percreta and placenta accreta/increta.

RESULTS

Among the 82 patients, 29 (35%) had placenta accreta/increta and 53 (65%) had placenta percreta. The best features to discriminate between placenta accreta/increta and placenta percreta with ultrasound were increased vascularization at the uterine serosa-bladder wall interface (odds ratio [OR] 7.93; 95% confidence interval [CI] 2.78-24.99; p < 0.01) and the number of lacunae without a hyperechogenic halo (OR 1.36; 95% CI 1.14-1.67; p = 0.012). Concerning MRI markers, heterogeneous placenta (OR 12.89; 95% CI 3.05-89.16; p = 0.002), dark intraplacental bands (OR 12.89; 95% CI 3.05-89.16; p = 0.002) and bladder wall interruption (OR 15.89; 95% CI 4.78-73.33; p < 0.001) had a higher OR in discriminating placenta accreta/increta from placenta percreta. The nomogram yielded areas under the curve of 0.841 (95% CI 0.754-0.927) and 0.856 (95% CI 0.767-0.945), after bootstrap resampling, for the accurate prediction of placenta percreta.

CONCLUSIONS

The nomogram we developed to predict the risk of placenta percreta among patients with PAS had good discriminative capabilities. This performance and its impact on maternal morbidity should be confirmed by future prospective studies.

Morbidly Adherent Placenta in the First Trimester with Consecutive Hysterectomy

Background Morbidly adherent placenta (MAP) represents a risk factor for a maternal adverse outcome and its incidence continues to rise following the increasing rate of caesarean deliveries. The detection of a pathology of placental adherence in the first trimester is challenging. Transvaginal ultrasound represents (TVUS) a reliable tool for accurate and timely diagnosis. Case We report on a case of MAP in a pregnant woman at 10 weeks of gestation with two prior caesarean deliveries. She presented with abdominal pain and hematometra. The first trimester diagnosis was made with TVUS and confirmed with magnetic resonance imaging. The patient required an urgent hysterectomy. Conclusion Antenatal care in the first trimester in women with a previous cesarean delivery should include a detailed examination of the placenta with TVUS.

Conservative management or cesarean hysterectomy for placenta accreta spectrum: the PACCRETA prospective study

BACKGROUND

Placenta accreta spectrum is a life-threatening condition that has increased dramatically in recent decades along with cesarean rates worldwide. Cesarean hysterectomy is widely practiced in women with placenta accreta spectrum; however, the maternal outcomes after cesarean hysterectomy have not been thoroughly compared with the maternal outcomes after alternative approaches, such as conservative management.

OBJECTIVE

This study aimed to compare the severe maternal outcomes between women with placenta accreta spectrum treated with cesarean hysterectomy and those treated with conservative management (leaving the placenta in situ).

STUDY DESIGN

From a source population of 520,114 deliveries in 176 hospitals (PACCRETA study), we designed an observational cohort of women with placenta accreta spectrum who had either a cesarean hysterectomy or a conservative management (the placenta left in situ) during cesarean delivery. Clinicians prospectively identified women meeting the inclusion criteria and included them at delivery. Data collection started only after the women had received information and agreed to participate in the study in the immediate postpartum period. The primary outcome was the transfusion of >4 units of packed red blood cells within 6 months after delivery. Secondary outcomes were other maternal complications within 6 months. We used propensity score weighting to account for potential indication bias.

RESULTS

Here, 86 women had conservative management and 62 women had cesarean hysterectomy for placenta accreta spectrum during cesarean delivery. The primary outcome occurred in 14 of 86 women in the conservative management group (16.3%) and 36 of 61 (59.0%) in the cesarean hysterectomy group (risk ratio in propensity score weighted model, 0.29; 95% confidence interval, 0.19-0.45). The rates of hysterectomy, total estimated blood loss exceeding 3000 mL, any blood product transfusion, adjacent organ injury, and nonpostpartum hemorrhage-related severe maternal morbidity were lower with conservative management than with cesarean hysterectomy (all adjusted, P≤.02); but, the rates of arterial embolization, endometritis, and readmission within 6 months of discharge were higher with conservative management than with cesarean hysterectomy.

CONCLUSION

Among women with placenta accreta spectrum who underwent cesarean delivery, conservative management was associated with a lower risk of transfusion of >4 units of packed red blood cells within 6 months than cesarean hysterectomy.

Life After Amsterdam: Placental Pathology Consensus Recommendations and Beyond

The Amsterdam Placental Workshop Group Consensus Statement on Sampling and Definitions of Placental Lesions has become widely accepted and is increasingly used as the universal language to describe the most common pathologic lesions found in the placenta. This review summarizes the most salient aspects of this seminal publication and the subsequent emerging literature based on Amsterdam definitions and criteria, with emphasis on publications relating to diagnosis, grading, and staging of placental pathologic conditions. We also provide an overview of the recent expert recommendations on the pathologic grading of placenta accreta spectrum, with insights on their clinical context. Finally, we discuss the emerging entity of SARS-CoV2 placentitis.

Risk of Subsequent Hysterectomy after Expectant Management in the Treatment of Placenta Accreta Spectrum Disorders

Management strategies for pregnancies with abnormal adherence/invasion of the placenta (placenta accreta spectrum, PAS) vary between centers. Expectant management (EM), defined as leaving the placenta in situ after the delivery of the baby, until its complete decomposition and elimination, has become a potential option for PAS disorders in selected cases, in which the risk of Caesarean hysterectomy is very high. However, expectant management has its own risks and complications. The aim of this study was to describe the rates of subsequent hysterectomy (HT) in patients that underwent EM for the treatment of PAS disorders. We reviewed the literature on the subject and found 12 studies reporting cases of HT after initial intended EM. The studies included 1918 pregnant women diagnosed with PAS, of whom 518 (27.1%) underwent EM. Out of these, 121 (33.2%) required subsequent HT in the 12 months following delivery. The rates of HT after initial EM were very different between the studies, ranging from 0 to 85.7%, reflecting the different characteristics of the patients and different institutional management protocols. Prospective multicenter studies, in which the inclusion criteria and management strategies would be uniform, are needed to better understand the role EM might play in the treatment of PAS disorders.

Achados na ressonância magnética do espectro do acretismo placentário: ensaio iconográfico

Resumo Acretismo placentário é uma condição caracterizada pela implantação anormal da placenta, que pode ser subdividida em três espectros de acordo com o seu grau de invasão: placenta acreta (ultrapassa a decídua basal e adere ao miométrio), placenta increta (penetra o miométrio) e placenta percreta (invasão da serosa uterina ou de tecidos/órgãos adjacentes). A incidência de acretismo placentário aumentou significativamente nas últimas décadas, principalmente em função da elevação das taxas de cesarianas, sendo este o seu principal fator de risco. A sua identificação pré-natal precisa permite um tratamento ideal com equipe multidisciplinar, minimizando significativamente a morbimortalidade materna. Os exames de escolha são a ultrassonografia e a ressonância magnética (RM), sendo a RM um método complementar indicado quando a avaliação ultrassonográfica é duvidosa, para pacientes com fatores de risco para acretismo placentário ou quando a placenta tem localização posterior. A RM é preferível também para avaliar invasão de órgãos adjacentes, oferecendo um campo de visão mais amplo, o que melhora o planejamento cirúrgico. Diversas características na RM são descritas no acretismo placentário, incluindo bandas hipointensas em T2 intraplacentárias, protuberância uterina anormal e heterogeneidade placentária. O conhecimento desses achados e a combinação de mais de um critério aumentam a confiabilidade do diagnóstico.

Potentially Preventable Primary Cesarean Sections in Future Placenta Accreta Spectrum

OBJECTIVE

Prior cesarean delivery is a well-known risk factor for placenta accreta spectrum disorders. While primary cesarean section is unavoidable in some patients, in others it may not be clearly indicated. The aim of the study is to determine the proportion of patients with placenta accreta spectrum who had a potentially preventable primary cesarean section and to identify factors associated with preventable placenta accreta spectrum.

STUDY DESIGN

This was a single-center retrospective cohort study of women with pathology-confirmed placenta accreta spectrum from 2007 to 2019. Primary cesarean sections were categorized as potentially preventable or unpreventable based on practice consistent with the American College of Obstetricians and Gynecologists and the Society for Maternal-Fetal Medicine "Safe Prevention of the Primary Cesarean Delivery" recommendations. Fisher's exact test and Mann-Whitney U-test were used for comparison with p <0.05 considered statistically significant.

RESULTS

Seventy-two patients had pathology-confirmed placenta accreta spectrum over the course of the study period, 15 (20.8%) of whom required a cesarean hysterectomy at the time of primary cesarean section. Fifty-seven patients had placenta accreta spectrum in a pregnancy following their primary cesarean section. Of these, 29 (50.9%) were considered potentially preventable. Most were performed without clear medical indication (37.9%) or for fetal malpresentation without attempted external cephalic version (37.9%). The remainder were due to arrest of labor not meeting criteria (17.2%) and abnormal or indeterminate fetal heart patterns with documented recovery (6.9%). Of the 11 patients without clear medical indication for primary cesarean section, eight (72.7%) were patient-choice cesarean sections and three (27.3%) were for suspected fetal macrosomia with estimated fetal weights not meeting criteria for cesarean delivery. There was no difference in the incidence of potentially preventable primary cesarean sections before and after the ACOG-SMFM "Safe Prevention of the Primary Cesarean Delivery" publication (48.8 vs. 57.1%, p = 0.59). Privately insured patients were more likely to have a potentially preventable primary cesarean section than those with Medicaid (62.5 vs. 23.5%, p = 0.008) and were more likely to have a primary cesarean section without clear medical indication (81.8 vs. 18.2%, p = 0.004).

CONCLUSION

Many patients with placenta accreta spectrum had a potentially preventable primary cesarean section. Most were performed without clear medical indication or for malpresentation without attempted external cephalic version, suggesting that at least a subset of placenta accreta spectrum cases may be preventable. This was particularly true for privately insured patients. These findings call for continued investigation of potentially preventable primary cesarean sections with initiatives to address concerns at the patient, provider, and hospital level.

KEY POINTS

· Many patients with placenta accreta spectrum have potentially preventable primary cesarean sections.. · Privately insured patients are more likely to have potentially preventable primary cesarean sections.. · Our findings suggest that at least a subset of placenta accreta spectrum cases may be preventable..

Emergent versus planned delivery in patients with placenta accreta spectrum disorders: A retrospective study

ABSTRACT

The aim of this study is to compare the clinical outcomes and to identify risk factors for emergent cesarean delivery and planned cesarean delivery in patients with placenta accreta spectrum (PAS) disorders in Vietnam.The medical records of patients admitted to our hospital with a diagnosis of PAS disorders >5 years were retrospectively reviewed.A total of 255 patients with PAS disorders were identified, including 95 cases in the emergent delivery group and 160 cases in the planned delivery group. The percentage of complete/partial placenta previa in the planned delivery group was significantly higher than that in the emergent delivery group (59.22% vs 32.16%, P = .027). Fewer patients in the planned group had vaginal bleeding compared with those in the emergent group (29 vs 36 cases, P < .001). The percentage of blood transfusion was similar between the 2 groups; however, the transfused units of pack red blood cells were greater in the emergent delivery group (5.3 ± 0.33 vs 4.5 ± 0.25 U, P = .036). When considering the neonatal outcomes, the data demonstrated that the planned delivery group had a significantly higher birth weight and a lower rate of preterm delivery than the emergent group (P < .001). The mean gestational age at delivery for the emergent group was 35.1 ± 0.27 weeks compared with 38.0 ± 0.10 weeks for the planned group (P < .001). The increased risk factors for emergent delivery were vaginal bleeding (odds ratio 2.86, 95% confidence interval 1.59-5.26) and preterm delivery (odds ratio 5.26, 95% confidence interval 2.13-14.29).Planned delivery is strongly associated with a lower need for blood transfusion and better neonatal outcomes compared with emergent delivery. Antenatal vaginal bleeding and preterm labor are risk factors for emergent delivery among patients with PAS disorders. Based on the results of this study, we recommend that the management strategies for patients with PAS disorders should be individualized to determine the optimal timing of delivery and to decrease the rate of emergent cesarean delivery.

Anesthetic management of placenta accreta spectrum at an academic center and a comparison of the combined spinal epidural with the double catheter technique: A retrospective study

STUDY OBJECTIVES

To describe the anesthetic management and outcomes of placenta accreta spectrum (PAS) cases at our institution over a 19 year period and to compare outcomes associated with the lumbar combined spinal epidural (CSE) technique versus the double catheter technique (lumbar CSE with thoracic epidural catheter).

DESIGN

Retrospective cohort study.

SETTING

Labor and delivery unit at a tertiary care center.

PATIENTS

113 female patients who had histologically confirmed PAS on the final pathology report after cesarean delivery or cesarean hysterectomy.

INTERVENTION

Neuraxial anesthesia, including CSE and the double catheter technique, and general anesthesia for PAS cases (including scheduled and unscheduled cases and those known or unknown as PAS preoperatively).

MEASUREMENTS

The medical records were reviewed for demographic information, intraoperative management, anesthetic technique, and outcomes. We describe anesthetic management and outcomes of cases classified as scheduled vs. unscheduled and known vs. unknown PAS. We also compare the CSE and double catheter techniques with the primary outcome being conversion to general anesthesia (GA).

MAIN RESULTS

We included 113 cases: 60 (53.1%) scheduled/known cases, 12 (10.6%), scheduled/unknown cases, 22 (19.5%) unscheduled/known, and 19 (16.8%) unscheduled/unknown cases. All scheduled cases except two were started with a neuraxial technique. General anesthesia (GA) was used to start 18/41 (44%) of unscheduled cases. The double catheter technique (n = 35) was associated with a lower GA conversion rate (5.7% vs. 29.7%, P = 0.036) compared to the CSE technique (n = 37).

CONCLUSIONS

Neuraxial anesthesia is the most commonly used technique for PAS cases in our practice. The double catheter technique was associated with lower GA conversion rates compared to the CSE technique in our cohort.

Diagnostic performance of radiologists with different levels of experience in the interpretation of MRI of the placenta accreta spectrum disorder

OBJECTIVES

There have been no investigations on the association between previous abdominopelvic MRI experience without placental MRI experience and diagnostic accuracy of placenta accreta spectrum (PAS). To evaluate the diagnostic performance of radiologists with different experience levels in interpreting PAS-related MRI findings.

METHODS

This retrospective study included 60 women who underwent MRI for placental assessment between 2016 and 2020. MR images were reviewed by four radiologists who were blinded to the clinical outcomes and had different experience levels in interpreting PAS-related MRI findings. The radiologists' diagnostic performance was evaluated according to the pathologic and surgical outcomes. Simple κ statistics were calculated to determine agreement among the radiologists.

RESULTS

Of 60 women, 46 were diagnosed with PAS. The maternal age mean ± SD was 33.0 years ± 5.0 for the PAS absent group and 36.0 ± 4.3 for the PAS present group (p = 0.013). Overall, the most experienced radiologist had the highest sensitivity (100%, 95% confidence interval (CI): 92.3-100%) and NPV (100%, 95% CI: 63.1-100%) in PAS diagnoses. However, the PPV and specificity were independent of experience. The most experienced radiologist had the highest diagnostic accuracy in PAS (90%, 95% CI: 79.5-96.2%) and placenta percreta (95%, 95% CI: 86.1-99.0%). There was a strong association between definitive PAS diagnoses and the highest experience level. The κ values for the interobserver agreement regarding PAS diagnoses were 0.67 for the most experienced radiologist (p < 0.001) and 0.38, 0.40, and 0.43 for the other radiologists (p = 0.001) and regarding placenta percreta diagnoses were 0.87 for the senior radiologist (p < 0.001) and 0.63, 0.57, and 0.62 for the other radiologists (p < 0.001).

CONCLUSION

Previous experience in interpreting PAS-related MRI findings plays a significant role in accurately interpreting such imaging findings. Previous abdominopelvic MRI experience without specific placental MRI experience did not improve diagnostic performance.

ADVANCES IN KNOWLEDGE

We believe that our study makes a significant contribution to the literature and that this paper will be of interest to the readership of your journal because to the best of our knowledge, this study is the first in which the correlation between previous experience in abdominopelvic MRI with no specific experience in PAS-related MRI and diagnostic accuracy of radiologists has been explored. Our results could aid in setting up specialized multidisciplinary teams to assist women with PAS disorders.

Placenta Accreta Spectrum

Placenta accreta spectrum (PAS) refers to the range of pathologic adherence of the placenta to the uterine myometrium, including the placenta accreta, increta, and percreta. The incidence of PAS is rising primarily because of an increase in related risk factors, such as the rate of cesarean deliveries and pregnancies resulting from assisted reproductive technology. The maternal risks associated with PAS are significant, including hemorrhage, hysterectomy, and death. Fetal and neonatal risks are primarily the result of premature delivery. Antenatal diagnosis via ultrasonography and magnetic resonance imaging remains imperfect. Management of PAS varies, however, and there is a clear improvement in maternal outcomes with an antenatal diagnosis compared with unexpected diagnosis at the time of delivery. Studies that evaluate the balance between maternal and fetal/neonatal risks of expectant management versus preterm delivery have found that planned delivery between 34 and 35 weeks' gestation optimizes outcomes. Multidisciplinary PAS care teams have become the norm and recommended approach to management, given the complexity of caring for this obstetrical condition. Although significant advances have been made over the years, large knowledge gaps remain in understanding the pathophysiology, diagnosis, and clinical management.

Trends, characteristics, and outcomes of placenta accreta spectrum: a national study in the United States

BACKGROUND

Although an infrequent occurrence, the placenta can adhere abnormally to the gravid uterus leading to significantly high maternal morbidity and mortality during cesarean delivery. Contemporary national statistics related to a morbidly adherent placenta, referred to as placenta accreta spectrum, are needed.

OBJECTIVE

This study aimed to examine national trends, characteristics, and perioperative outcomes of women who underwent cesarean delivery for placenta accreta spectrum in the United States.

STUDY DESIGN

This is a population-based retrospective, observational study querying the National Inpatient Sample. The study cohort included women who underwent cesarean delivery from October 2015 to December 2017 and had a diagnosis of placenta accreta spectrum. The main outcome measures were patient characteristics and surgical outcomes related to placenta accreta spectrum assessed by the generalized estimating equation on multivariable analysis. The temporal trend of placenta accreta spectrum was also assessed by linear segmented regression with log transformation.

RESULTS

Of 2,727,477 cases who underwent cesarean delivery during the study period, 8030 (0.29%) had the diagnosis of placenta accreta spectrum. Placenta accreta was the most common diagnosis (n=6205, 0.23%), followed by percreta (n=1060, 0.04%) and increta (n=765, 0.03%). The number of placenta accreta spectrum cases increased by 2.1% every quarter year from 0.27% to 0.32% (P=.004). On multivariable analysis, (1) patient demographics (older age, tobacco use, recent diagnosis, higher comorbidity, and use of assisted reproductive technology), (2) pregnancy characteristics (placenta previa, previous cesarean delivery, breech presentation, and grand multiparity), and (3) hospital factors (urban teaching center and large bed capacity hospital) represented the independent characteristics related to placenta accreta spectrum (all, P<.05). The median gestational age at cesarean delivery was 36 weeks for placenta accreta and 34 weeks for both placenta increta and percreta vs 39 weeks for non-placenta accreta spectrum cases (P<.001). On multivariable analysis, cesarean delivery complicated by placenta accreta spectrum was associated with increased risk of any surgical morbidities (78.3% vs 10.6%), Centers for Disease Control and Prevention-defined severe maternal morbidity (60.3% vs 3.1%), hemorrhage (54.1% vs 3.9%), coagulopathy (5.3% vs 0.3%), shock (5.0% vs 0.1%), urinary tract injury (8.3% vs 0.2%), and death (0.25% vs 0.01%) compared with cesarean delivery without placenta accreta spectrum. When further analyzed by subtype, cesarean delivery for placenta increta and percreta was associated with higher likelihood of hysterectomy (0.4% for non-placenta accreta spectrum, 45.8% for accreta, 82.4% for increta, 78.3% for percreta; P<.001) and urinary tract injury (0.2% for non-placenta accreta spectrum, 5.2% for accreta, 11.8% for increta, 24.5% for percreta; P<.001). Moreover, women in the placenta increta and percreta groups had markedly increased risks of surgical mortality compared with those without placenta accreta spectrum (increta, odds ratio, 19.9; and percreta, odds ratio, 32.1).

CONCLUSION

Patient characteristics and outcomes differ across the placenta accreta spectrum subtypes, and women with placenta increta and percreta have considerably high surgical morbidity and mortality risks. Notably, 1 in 313 women undergoing cesarean delivery had a diagnosis of placenta accreta spectrum by the end of 2017, and the incidence seems to be higher than reported in previous studies.

Comparison of Magnetic Resonance Imaging of the Lower Uterine Segment in Pregnant Women with Central Placenta Previa with and without Placenta Accreta Spectrum from a Single Center

BACKGROUND Placenta accreta spectrum (PAS) includes placenta increta, placenta percreta, and placenta accreta. PAS is due to abnormal decidualization and can lead to severe maternal hemorrhage and occurs in up to 3% of women with central placental previa (CPP). This study from a single center aimed to compare the magnetic resonance imaging (MRI) changes in the lower uterine segment in pregnant women with CPP, with and without PAS. MATERIAL AND METHODS This retrospective study includes 90 pregnant women with PAS and 66 pregnant women without PAS. All participants were confirmed to have CPP by MRI. Eight MRI parameters were assessed and compared with perinatal outcomes for mothers and newborns. RESULTS The pregnancies in the non-PAS group had less operative time (P=0.001), less intrapartum hemorrhage (P<0.001), and less blood transfusion than the PAS group (P<0.001). The 8 MRI variables with different odds ratios were placenta thickness (4.20), cervical lengths (3.27), placental dark T2 bands area (5.10), cervical marginal sinus (3.04), bladder bulge (3.55), myometrial thinning (6.41), lower uterine segment bulge (4.61), and placental signals in the cervix (9.14). The sensitivity and specificity of MRI in the diagnosis of PAS were 82.22% and 91.09%, respectively, by the combined 8 MRI features, and the area under the curve (AUC) was 0.816. CONCLUSIONS The findings from this study showed that MRI of the lower uterine segment had high sensitivity and specificity for the diagnosis of PAS in pregnant women with CPP.

Proposal of a simple 2-hand technique at cesarean hysterectomy for placenta accreta spectrum

Placenta accreta spectrum (PAS) encompasses a range of disorders of placental trophoblastic tissue that is morbidly adherent to the underlying gravid uterus. Women with PAS commonly undergo surgical treatment with hysterectomy at cesarean delivery that is associated with significant surgical morbidity and mortality. Increased vascularity due to gestational change and the abnormally enlarged lower uterine segment due to the location of placenta make the surgery complex and morbid. Here, we propose a simple 2-hand technique that can be used to improve surgical outcomes of cesarean hysterectomy for PAS. Unlike the ordinary hysterectomy where the transection of the cardinal ligament is started at the isthmus below the low uterine segment, the proposed 2-hand technique allows transection of the cardinal ligament at the level of the lower uterine segment below the placental bed. This minimizes blood loss that may be associated with serial transection of cardinal ligament which occurs when it is transected at or above the placenta level. This surgical approach starts with demarcation of 3 anatomical landmarks [rectum (posterior aspect), ureters (lateral aspect), and bladder (anterior aspect)] in postero-anterior progression. Complete de-serosalization of posterior low uterine segment allows lateralization of the ureter and enables the uterus to be mobilized antero-caudally where the surgeon's hand can reach below the placental bed. After the bladder flap creation to the level of endopelvic fascia, the surgeon's two hands are placed antero-posteriorly at low uterine segment below the placental bed. The fingertips of both hands meet at the cardinal ligament below placenta at the level of the upper cervix. At this point the two hands are gently moved upwards, carrying the placenta-containing low uterine segment. This step enables creation of a safe anatomical distance from surrounding structures and isolation of the cardinal ligament where surgical clamp can be applied to transect the cardinal ligament.