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

Relationship between maternal serum sFlt-1 level and placenta accreta spectrum disorders in the third trimester

PURPOSE

This study aims to evaluate whether the third-trimester soluble fms-like tyrosine kinase-1 (sFlt-1) serum levels could be related to placenta accreta spectrum (PAS) disorders and the severity of postpartum blood loss.

METHODS

This was a nested case-control study which compared serum sFlt-1 level between gravid women with or without PAS disorders. Spearman correlation analysis was conducted to explore the relationship between sFlt-1 level and the volume of postpartum blood loss. Confounding factors were adjusted to avoid the impact on the results.

RESULTS

Sixty gravid women were enrolled: 36 women in the PAS group and 24 women in the non-PAS group. Women in the PAS group had a median sFlt-1 level of 9407.1 [2745.9-21,691.5] pg/ml, whereas women in the non-PAS group had a median sFlt-1 level of 25,779.2 [14317.1-35,626.7] pg/ml, (p < 0.001). The sFlt-1 level was negatively related to the volume of postpartum blood loss (r =  - 0.358, p = 0.041). After adjusting for maternal age and gestational age at blood taking, sFlt-1 level showed no significant relationship with PAS disorders (p = 0.245) and postpartum blood loss (p = 0.526).

CONCLUSION

Third-trimester sFlt-1 serum level is not independently associated with PAS disorders or postpartum blood loss after adjusting for confounding factors.

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

OBJECTIVE

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

STUDY DESIGN

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

RESULTS

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

CONCLUSION

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

KEY POINTS

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

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.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Uterine isthmic tourniquet left in situ as a new approach for placenta previa-accreta surgery: a comparative study

OBJECTIVES

Placenta previa-accreta spectrum disorders are a cause of obstetric hemorrhage that can lead to maternal fetal mortality and morbidity. We aimed to describe the use of a uterine isthmic tourniquet left in situ as a new uterus-preserving approach for patients with placenta previa-accreta.

METHODS

In this retrospective comparative study, the patients who underwent surgery for placenta previa between 2017 and 2024 at our tertiary hospital were reviewed. Primary outcome of the study is to evaluate feasibility of uterine isthmic tourniquet left in situ for uterine preserving by preventing postpartum hemorrhage for patients with placenta previa-accreta. As a secondary outcome, group 1 (n=28) patients who were managed with uterine isthmic tourniquet left in place were compared with patients in group 2 (n=32) who were managed with only bilateral uterine artery ligation.

RESULTS

This new approach uterine isthmic tourniquet technique prevented postpartum hemorrhage with a rate of 100 percent in group 1 patients, while uterine artery ligation prevented postpartum hemorrhage with a rate of 75 % in group 2. Postoperative additional interventions (relaparotomy hysterectomy, balloon tamponade application, uterine or vaginal packing) were performed for eight patients in group 2 (25 %) but not in group 1 (0 %) (p=0.015). The haemoglobin levels before caesarean section were similar in both groups (p=0.235), while the postoperative haemoglobin levels were lower in group 2 (9.69 ± 1.37 vs. 8.15 ± 1.32) (p=0.004). Erythrocyte suspension was given to two patients in group 1 and 12 patients in group 2 (2/28 7 % vs. 12/32 37 %, p=0.018).

CONCLUSIONS

The uterine isthmic tourniquet left in situ technique is a safe, simple and effective for preventing postpartum hemorrhage and preserving uterus during placenta previa accreta surgery as superior to uterine artery ligation alone.

Quantifying placenta accreta spectrum severity and its associated blood loss: a novel transvaginal ultrasound scoring system

BACKGROUND

Hemorrhage associated with placenta accreta spectrum (PAS) is a leading cause of maternal morbidity and mortality. Estimating blood loss in these individuals is a critical component of comprehensive preoperative planning.

OBJECTIVE

A semiquantitative score based on transvaginal ultrasound was developed and tested to predict PAS, estimate its severity, and blood loss in individuals with clinical and ultrasound evidence suggesting PAS.

STUDY DESIGN

A secondary analysis was conducted of prospectively collected data from a quaternary center of patients with suspected accreta on 2D ultrasound and clinical suspicion. A predetermined scoring system was applied based on three components: (1) uterine wall (score 0: no loss of hypo-translucent uterine wall with overlying placenta in the lower uterine segment; 1: loss of hypo-translucent <3-cm defect; 2: 3-6-cm defect; and 3: >6-cm defect); (2) arterial vascularity at the uterine wall defect (score 0: no vessels observed; 1: 1-2 vessels over the defect; 2: 3-5 vessels; and 3: >5 vessels); and (3) cervical involvement (score 0: normal cervical length without previa; 1: previa with normal cervical length; 2: short cervix with previa, minimal vascularity and small lacunae; 3: short cervix with previa, increased vascularity and large lacunae). Each patient's three domain scores determined a cumulative, final score of 0-9. Patients were managed at the discretion of a multi-disciplinary team and patient's preference among the following options: cesarean delivery with placenta removal, cesarean delivery with placenta in-situ (conservative) with or without delayed hysterectomy, or cesarean hysterectomy. The frequency of different degrees of placental invasion per pathology examination per score unit was registered. Multiple linear regression analysis was performed for association of blood loss according to score adjusted by risk factors for PAS.

RESULTS

A total of 73 patients were evaluated. All 11 patients who had a score of 0 had cesarean delivery with placenta removal without evidence of intraoperative PAS, thus resulting in a 100% negative predictive value. The remaining 62 had scores between 1 and 9. Among patients with scores 0-3 (n=20), only one had intraoperative PAS, yielding a negative predictive value of 97%. Higher scores were associated with severe PAS forms (r=0.301, P=.02). Based on the associations between PAS scores, clinical correlation, and blood loss, we divided patients into four categories: Category 0: PAS score 0; Category 1: scores 1-3; Category 2: scores 4-6; and Category 3: scores 7-9. The median blood loss in Category 0=635±352 mL, Category 1=634±599 mL, Category 2=1549±1284 mL, and Category 3=1895±2106 mL (P<.001). On multivariable analysis, Category 2 (β=0.97, P<.01) and Category 3 (β=1.26, P<.003) were associated with significantly greater blood loss than Category 0, irrespective of type of surgery.

CONCLUSION

The transvaginal ultrasound score separates groups at low risk (Category 0) and at higher risk of PAS (Categories 1-3). Categories 1-3 may provide important clinical information to estimate the risk of severe forms of PAS and of blood loss during surgery. VIDEO ABSTRACT.

Pregnancy with endometriosis: Assessment of national-level trends, characteristics, and maternal morbidity at delivery

OBJECTIVE

To examine pregnancy characteristics and maternal morbidity at delivery among pregnant patients with a diagnosis of endometriosis.

STUDY DESIGN

This cross-sectional study queried the Healthcare Cost and Utilization Project's National Inpatient Sample. Study population was 17,796,365 hospital deliveries from 2016 to 2020, excluded adenomyosis and uterine myoma. The exposure was endometriosis diagnosis. Main outcome measures were clinical and pregnancy characteristics and severe maternal morbidity at delivery related to endometriosis, assessed with multivariable regression model.

RESULTS

Endometriosis was diagnosed in 17,590 patients. The prevalence of endometriosis increased by 24 % from one in 1,191 patients in 2016 to one in 853 patients in 2020 (adjusted-odds ratio [aOR] 1.24, 95% confidence interval [CI] 1.19-1.30). Clinical and pregnancy characteristics that had greater than two-fold association to endometriosis included polycystic ovary syndrome, placenta previa, cesarean delivery, maternal age of ≥30 years, prior pregnancy loss, and anxiety disorder. Pregnant patients with endometriosis were more likely to have the diagnosis of measured severe maternal morbidity during the index hospitalization for delivery (47.8 vs 17.3 per 1,000 deliveries, aOR 1.91, 95%CI 1.78-2.06); these associations were more prominent following vaginal (aOR 2.82, 95%CI 2.41-3.30) compared to cesarean (aOR 1.85, 95%CI 1.71-2.00) deliveries. Among the individual morbidity indicators, endometriosis was most strongly associated with thromboembolism (aOR 5.05, 95%CI 3.70-6.91), followed by sepsis (aOR 2.39, 95%CI 1.85-3.09) and hysterectomy (aOR 2.18, 95%CI 1.85-2.56). When stratified for endometriosis anatomical site, odds of thromboembolism was increased in endometriosis at distant site (aOR 9.10, 95%CI 3.76-22.02) and adnexa (aOR 7.37, 95%CI 4.43-12.28); odds of sepsis was most increased in endometriosis at multi-classifier locations (aOR 7.33, 95%CI 2.93-18.31) followed by pelvic peritoneum (aOR 5.54, 95%CI 2.95-10.40); and odds of hysterectomy exceeded three-fold in endometriosis at adnexa (aOR 3.00, 95%CI 2.30-3.90), distant site (aOR 5.36, 95%CI 3.48-8.24), and multi-classifier location (aOR 4.46, 95%CI 2.11-9.41).

CONCLUSION

The results of this nationwide analysis suggest that pregnancy with endometriosis is uncommon but gradually increasing over time in the United States. The data also suggest that endometriosis during pregnancy is associated with increased risk of severe maternal morbidity at delivery, especially for thromboembolism, sepsis, and hysterectomy. These morbidity risks differed by the anatomical location of endometriosis.

Diagnosis of placenta accreta spectrum using ultrasound texture feature fusion and machine learning

INTRODUCTION

Placenta accreta spectrum (PAS) is an obstetric disorder arising from the abnormal adherence of the placenta to the uterine wall, often leading to life-threatening complications including postpartum hemorrhage. Despite its significance, PAS remains frequently underdiagnosed before delivery. This study delves into the realm of machine learning to enhance the precision of PAS classification. We introduce two distinct models for PAS classification employing ultrasound texture features.

METHODS

The first model leverages machine learning techniques, harnessing texture features extracted from ultrasound scans. The second model adopts a linear classifier, utilizing integrated features derived from 'weighted z-scores'. A novel aspect of our approach is the amalgamation of classical machine learning and statistical-based methods for feature selection. This, coupled with a more transparent classification model based on quantitative image features, results in superior performance compared to conventional machine learning approaches.

RESULTS

Our linear classifier and machine learning models attain test accuracies of 87 % and 92 %, and 5-fold cross validation accuracies of 88.7 (4.4) and 83.0 (5.0), respectively.

CONCLUSIONS

The proposed models illustrate the effectiveness of practical and robust tools for enhanced PAS detection, offering non-invasive and computationally-efficient diagnostic tools. As adjunct methods for prenatal diagnosis, these tools can assist clinicians by reducing the need for unnecessary interventions and enabling earlier planning of management strategies for delivery.

Assessment of obstetric characteristics and outcomes associated with pregnancy with Turner syndrome

OBJECTIVE

To assess national-level trends, characteristics, and outcomes of pregnancies with Turner syndrome in the United States.

DESIGN

Cross-sectional study.

SETTING

The Healthcare Cost and Utilization Project's National Inpatient Sample.

SUBJECTS

A total of 17,865,495 hospital deliveries from 2016-2020.

EXPOSURE

A diagnosis of Turner syndrome, identified according to the World Health Organization's International Classification of Disease 10th revision code of Q96.

MAIN OUTCOME MEASURES

Obstetrics outcomes related to Turner syndrome, assessed with inverse probability of treatment weighting cohort and multivariable binary logistic regression modeling.

RESULTS

The prevalence of pregnant patients with Turner syndrome was 7.0 per 100,000 deliveries (one in 14,235). The number of hospital deliveries with patients who have a diagnosis of Turner syndrome increased from 5.0 to 11.7 per 100,000 deliveries during the study period (adjusted-odds ratio [aOR] for 2020 vs. 2016; 2.18, 95% confidence interval [CI] 1.83-2.60). Pregnant patients with Turner syndrome were more likely to have a diagnosis of pregestational hypertension (4.8% vs. 2.8%; aOR 1.65; 95% CI 1.26-2.15), uterine anomaly (1.6% vs. 0.4%; aOR, 3.01; 95% CI 1.93-4.69), and prior pregnancy losses (1.6% vs. 0.3%; aOR 4.70; 95% CI 3.01-7.32) compared with those without Turner syndrome. For the index obstetric characteristics, Turner syndrome was associated with an increased risk of intrauterine fetal demise (10.9% vs. 0.7%; aOR 8.40; 95% CI 5.30-13.30), intrauterine growth restriction (8.5% vs. 3.5%; aOR 2.11; 95% CI 1.48-2.99), and placenta accreta spectrum (aOR 3.63; 95% CI 1.20-10.97). For delivery outcome, pregnant patients with Turner syndrome were more likely to undergo cesarean delivery (41.6% vs. 32.3%; aOR 1.53; 95% CI 1.26-1.87). Moreover, the odds of periviable delivery (22-25 weeks: 6.1% vs. 0.4%; aOR 5.88; 95% CI 3.47-9.98) and previable delivery (<22 weeks: 3.3% vs. 0.3%; aOR 2.87; 95% CI 1.45-5.69) were increased compared with those without Turner syndrome.

CONCLUSIONS

The results of contemporaneous, nationwide assessment in the United States suggest that although pregnancy with Turner syndrome is uncommon this may represent a high-risk group, particularly for intrauterine fetal demise and periviable delivery. Establishing a society-based approach for preconception counseling and antenatal follow-up would be clinically compelling.

Comparative study of the prevalence of organ injury in placenta accreta spectrum disorder between posterior colpotomy and conventional peripartum hysterectomies at a single referral center in southern Thailand

OBJECTIVE

To compare the prevalence of adjacent organ injury in placenta accreta spectrum disorder (PAS) between the posterior colpotomy approach and conventional peripartum hysterectomy.

METHODS

This retrospective study analyzed the data of pregnant women diagnosed with PAS who underwent peripartum hysterectomy at Songklanagarind Hospital between January 2006 and December 2021. The patients were divided into two groups: posterior colpotomy and conventional approaches. The characteristics and surgical and obstetric outcomes were compared. Univariate and multivariate logistic regression was used to identify factors and risk of organ injury.

RESULTS

Among 174 patients, 64 underwent conventional peripartum hysterectomy, and 110 underwent the posterior colpotomy approach. The overall incidence of adjacent organ injury was 17.82%. Organ injury prevalence was lower in the posterior colpotomy group (10%) than in the conventional group (31.25%), with no difference in operative time. Multivariate analysis showed that posterior colpotomy reduced adjacent organ injury (odds ratio [OR] 0.18, 95% confidence interval [CI] 0.06-0.54, P = 0.002). Placenta percreta was associated with increased injury risk (OR 6.83, 95% CI 2.53-18.44, P < 0.002). Subgroup analysis showed that the posterior approach reduced bladder injury in placenta increta (OR 0.14, 95% CI 0.04-0.57, P = 0.003) and percreta (OR 0.19, 95% CI 0.05-0.77, P = 0.017).

CONCLUSION

Compared with conventional peripartum hysterectomy, the posterior colpotomy approach in patients with PAS reduced the risk of adjacent organ injury, particularly for placenta increta and percreta. This technique should be considered in PAS cases, but further investigations with a prospective study design are needed.

Application of Uterine Artery Embolization in Patients With Placenta Accreta Spectrum After Abdominal Aortic Balloon Occlusion

OBJECTIVE

To evaluate the application of different uterine artery embolization procedures under balloon occlusion of the abdominal aorta in patients with Placenta Accreta Spectrum (PAS) undergoing cesarean section.

MATERIALS AND METHODS

A retrospective analysis was performed on clinical data from 72 patients who underwent uterine artery embolization for hemostasis during cesarean section with PAS. The patients were divided into two groups according to the embolization method used during surgery: group A (n = 43) underwent uterine artery embolization by withdrawing the balloon and inserting a Cobra catheter into the uterine artery for embolization, while group B (n = 29) underwent uterine artery embolization with a Cobra catheter inserted via contralateral puncture of the femoral artery and balloon occlusion. General information, surgical data, and postoperative recovery were compared between the 2 groups.

RESULTS

The bleeding and transfusion volumes were lower in group B than in group A and the differences between the 2 groups were statistically significant. There were no significant differences in surgical duration, number of embolized vessels, length of hospital stay, postoperative complications, or menstrual recovery between the 2 groups.

CONCLUSION

For patients with PAS undergoing cesarean section, uterine artery embolization for hemostasis is preferably performed by inserting a Cobra catheter via contralateral puncture of the femoral artery under abdominal aortic balloon occlusion.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Diffusion-derived vessel density (DDVD) computed from a simple diffusion MRI protocol as a biomarker of placental blood circulation in patients with placenta accreta spectrum disorders: A proof-of-concept study

OBJECTIVES

Increasing trend of PAS (placenta accreta spectrum disorders) incidence is a major health concern as PAS is associated with high maternal morbidity and mortality during cesarean section. Prenatal identification of PAS is crucial for delivery planning and patients management. This study aims to explore whether diffusion-derived vessel density (DDVD) computed from a simple diffusion MRI protocol differs in PAS from normal placenta.

METHODS

We enrolled 86 patients with PAS disorders and 40 pregnant women without PAS disorders. Each patient underwent intravoxel incoherent motion (IVIM) MRI sequence with 11 b-values. Placenta diffusion-derived vessel density (DDVD-b0b50) was the signal difference between b = 0 and b = 50 s/mm2 images. DDVD(b0b50) A/N was calculated as [accreta lesion DDVD(b0b50)]/ [normal placenta DDVD(b0b50)]. The correlation between DDVD and gestational age was explored using Spearman rank correlation. Differences of DDVD(b0b50) A/N in patients with normal placentas and with PAS, and in patients with different subtypes of PAS were explored.

RESULTS

DDVD was negatively correlated with gestational age (p = 0.023, r = -0.359) in patients with normal placentas. DDVD(b0b50) A/N was significantly higher in patients with PAS (median:1.16, mean: 1.261) than normal placenta (median:1.02, mean: 1.032, p < 0.001) and especially higher in patients with placenta increta (median:1.14, mean: 1.278) and percreta (median: 1.20, mean: 1.396, p < 0.001).

CONCLUSION

As a higher DDVD indicates higher physiological volume of micro-vessels in PAS, this study suggests DDVD can be a potential biomarker to evaluate the placenta perfusion.

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

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

Leaving the Placenta In Situ in Placenta Accreta Spectrum Disorders: A Single-Center Case Series

OBJECTIVE

The most common treatment for placenta accreta spectrum (PAS) disorders is planned primary cesarean hysterectomy. However, other management strategies may improve outcomes and/or allow fertility preservation. The objective of this study was to describe the course and outcomes of patients with PAS managed by leaving the placenta in situ.

STUDY DESIGN

This is a series of 11 patients with PAS managed by leaving the placenta in situ at a single academic center in the United States from 2015 to 2022. The approach described involves delivery of the fetus via cesarean, no attempt at placental removal, closure of the hysterotomy, prophylactic intravenous antibiotics for up to 1 week, and close outpatient follow-up until the uterus is empty.

RESULTS

The uterus was successfully preserved in six (55%), minimally invasive hysterectomy was performed in four (36%), and abdominal hysterectomy was performed in 1 (9%). During cesarean delivery, the median estimated blood loss was 650mL (range: 200-1,000mL). The majority of patients had no vaginal discharge for several weeks after delivery, followed by brown or bloody discharge, and intermittent mild-to-moderate cramping. The median time to resolution of PAS was 18 weeks in patients with successful uterine preservation (range: 5-25 weeks). Indications for hysterectomy included hemorrhage (n=1), coagulopathy (n=1), endomyometritis (n=2), and pain (n=1), and these occurred at a median of 5 weeks postpartum (range: 1-25 weeks). Four patients had subsequent pregnancies of whom three were live births at or near term and one was a spontaneous abortion at 19 weeks.

CONCLUSION

Leaving the placenta in situ may be an appropriate management strategy for some carefully selected and counseled patients with PAS.

KEY POINTS

· Overall, 55% had uterine preservation (6/11).. · Minimally invasive approach in 80% of hysterectomies (4/5).. · Of patients, 67% with uterine preservation had subsequent pregnancies (4/6)..

Basal Plate Myofibers and the Risk of Placenta Accreta Spectrum in the Subsequent Pregnancy: A Large Single-Center Cohort

OBJECTIVE

We aimed to evaluate whether there is a significant association between a placental pathology diagnosis basal plate myofibers (BPMF) in an index pregnancy with placenta accreta spectrum (PAS) in the subsequent pregnancy.

STUDY DESIGN

We conducted a retrospective nested cohort study of all cases with a histopathological finding of BPMF between August 2012 and March 2020 at a single tertiary referral center. Data were collected for all subjects (cases and controls) with at least two consecutive pregnancies (the initial index pregnancy and at least one subsequent pregnancy) accompanied by a concomitant record of histopathological study of the placenta at our center. The primary outcome was pathologically confirmed PAS in the subsequent pregnancy. Data are presented as percentage or median, interquartile range accordingly.

RESULTS

A total of n = 1,344 participants were included, of which n = 119 (index cases) carried a contemporaneous histopathological diagnosis of BPMF during the index pregnancy and n = 1,225 did not (index controls). Among the index cases, patients with BPMF were older (31.0 [20, 42] vs. 29.0 [15, 43], p < 0.001), more likely to have undergone in vitro fertilization (IVF) for conception (10.9 vs. 3.8%, p = 0.001) and were of a more advanced gestational age at delivery (39.0 [25, 41] vs. 38.0 [20, 42], p = 0.006). In the subsequent pregnancy, the rate of PAS was significantly higher among the BPMF index cases (6.7 vs. 1.1%, p < 0.001). After adjusting for maternal age and IVF, a histopathological diagnosis of BPMF in an index pregnancy was shown to be a significant risk factor for PAS in the subsequent gestation (hazard ratio: 5.67 [95% confidence interval: 2.28, 14.06], p < 0.001).

CONCLUSION

Our findings support that a histopathological diagnosis of BPMF is an independent risk factor for PAS in the subsequent pregnancy.

KEY POINTS

· BPMF may indicate morbid adherence of placenta.. · Patients with BPMF were older and more likely to have undergone IVF for conception.. · The BPMF in the current pregnancy is an independent risk factor for PAS in the subsequent pregnancy..

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.

Characteristics and treatment for severe postpartum haemorrhage in different midwifery hospitals in one district of Beijing in China: an institution-based, retrospective cohort study

OBJECTIVE

To identify the characteristics and treatment approaches for patients with severe postpartum haemorrhage (SPPH) in various midwifery institutions in one district in Beijing, especially those without identifiable antenatal PPH high-risk factors, to improve regional SPPH rescue capacity.

DESIGN

Retrospective cohort study.

SETTING

This study was conducted at 9 tertiary-level hospitals and 10 secondary-level hospitals in Haidian district of Beijing from January 2019 to December 2022.

PARTICIPANTS

The major inclusion criterion was SPPH with blood loss ≥1500 mL or needing a packed blood product transfusion ≥1000 mL within 24 hours after birth. A total of 324 mothers with SPPH were reported to the Regional Obstetric Quality Control Office from 19 midwifery hospitals.

OUTCOME MEASURES

The pregnancy characteristics collected included age at delivery, gestational weeks at delivery, height, parity, delivery mode, antenatal PPH high-risk factors, aetiology of PPH, bleeding amount, PPH complications, transfusion volume and PPH management. SPPH characteristics were compared between two levels of midwifery hospitals and their association with antenatal PPH high-risk factors was determined.

RESULTS

SPPH was observed in 324 mothers out of 106 697 mothers in the 4 years. There were 74.4% and 23.9% cases of SPPH without detectable antenatal PPH high-risk factors in secondary and tertiary midwifery hospitals, respectively. Primary uterine atony was the leading cause of SPPH in secondary midwifery hospitals, whereas placental-associated disorders were the leading causes in tertiary institutions. Rates of red blood cell transfusion over 10 units, unscheduled returns to the operating room and adverse PPH complications were higher in patients without antenatal PPH high-risk factors. Secondary hospitals had significantly higher rates of trauma compared with tertiary institutions.

CONCLUSION

Examining SPPH cases at various institutional levels offers a more comprehensive view of regional SPPH management and enhances targeted training in this area.

Annual numbers of diagnoses and medical expenses for obstetric diseases in Japan: A report from the National Database of Health Insurance Claims

AIM

The present study aimed to estimate the total numbers of obstetric diseases diagnosed, total amounts of medical expenses claimed for obstetric diseases, their averages per livebirth, and yearly trends in Japan.

METHODS

This is a secondary analysis of the National Database of Health Insurance Claims and Specific Health Checkups of Japan (NDB) (data from 2015 to 2019). The target population was women of reproductive age (15-49 years old) with diseases in pregnancy, childbirth, and the puerperium, defined by having O codes according to the International Classification of Diseases 10th Revision. We calculated the numbers of obstetric diseases diagnosed, amounts of medical expenses claimed for obstetric diseases marked with the "main injury/disease decision flag," and the totals divided by the annual numbers of livebirths, by year and women's age group.

RESULTS

From 2015 to 2019, both the numbers of obstetric diseases diagnosed and amounts of medical expenses claimed for obstetric diseases per livebirth were on an upward trend, whereas the total numbers of obstetric diseases diagnosed were decreased. Women in advanced age groups had a higher number of diagnoses and a higher amount of medical expenses for obstetric diseases per livebirth. "Preterm labour without delivery" had the highest amounts of medical expenses claimed for and the second highest numbers of diagnoses throughout the study period.

CONCLUSIONS

This study suggests that pregnant women in Japan would have an increasing number of obstetric complications and necessary medical expenses year by year. Further study is warranted to elucidate these trends and identify possible mitigation measures.

Contraception and sterilization selection at delivery among pregnant patients with malignancy

INTRODUCTION

Since malignancy during pregnancy is uncommon, information regarding contraception selection or sterilization at delivery is limited. The objective of this study was to examine the type of long-acting reversible contraception or surgical sterilization procedure chosen by pregnant patients with malignancy at delivery.

MATERIAL AND METHODS

This cross-sectional study queried the Healthcare Cost and Utilization Project's National Inpatient Sample in the USA. The study population was vaginal and cesarean deliveries in a hospital setting from January 2017 to December 2020. Pregnant patients with breast cancer (n = 1605), leukemia (n = 1190), lymphoma (n = 1120), thyroid cancer (n = 715), cervical cancer (n = 425) and melanoma (n = 400) were compared with 14 265 319 pregnant patients without malignancy. The main outcome measures were utilization of long-acting reversible contraception (subdermal implant or intrauterine device) and performance of permanent surgical sterilization (bilateral tubal ligation or bilateral salpingectomy) during the index hospital admission for delivery, assessed with a multinomial regression model controlling for clinical, pregnancy and delivery characteristics.

RESULTS

When compared with pregnant patients without malignancy, pregnant patients with breast cancer were more likely to proceed with bilateral salpingectomy (adjusted odds ratio [aOR] 2.30) or intrauterine device (aOR 1.91); none received the subdermal implant. Pregnant patients with leukemia were more likely to choose a subdermal implant (aOR 2.22), whereas those with lymphoma were more likely to proceed with bilateral salpingectomy (aOR 1.93) and bilateral tubal ligation (aOR 1.76). Pregnant patients with thyroid cancer were more likely to proceed with bilateral tubal ligation (aOR 2.21) and none received the subdermal implant. No patients in the cervical cancer group selected long-acting reversible contraception, and they were more likely to proceed with bilateral salpingectomy (aOR 2.08). None in the melanoma group chose long-acting reversible contraception. Among pregnant patients aged <30, the odds of proceeding with bilateral salpingectomy were increased in patients with breast cancer (aOR 3.01), cervical cancer (aOR 2.26) or lymphoma (aOR 2.08). The odds of proceeding with bilateral tubal ligation in pregnant patients aged <30 with melanoma (aOR 5.36) was also increased.

CONCLUSIONS

The results of this nationwide assessment in the United States suggest that among pregnant patients with malignancy, the preferred contraceptive option or method of sterilization at time of hospital delivery differs by malignancy type.

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.

Unraveling the molecular mechanisms driving enhanced invasion capability of extravillous trophoblast cells: a comprehensive review

Precise extravillous trophoblast (EVT) invasion is crucial for successful placentation and pregnancy. This review focuses on elucidating the mechanisms that promote heightened EVT invasion. We comprehensively summarize the pivotal roles of hormones, angiogenesis, hypoxia, stress, the extracellular matrix microenvironment, epithelial-to-mesenchymal transition (EMT), immunity, inflammation, programmed cell death, epigenetic modifications, and microbiota in facilitating EVT invasion. The molecular mechanisms underlying enhanced EVT invasion may provide valuable insights into potential pathogenic mechanisms associated with diseases characterized by excessive invasion, such as the placenta accreta spectrum (PAS), thereby offering novel perspectives for managing pregnancy complications related to deficient EVT invasion.

Diagnostic Role of Cell-Free miRNAs in Identifying Placenta Accreta Spectrum during First-Trimester Screening

Placenta accreta spectrum (PAS) is a severe complication of pregnancy associated with excessive invasion of cytotrophoblast cells at the sites of the endometrial-myometrial interface and the myometrium itself in cases of adherent (creta) and invasive (increta and percreta) forms, respectively. This leads to a high risk of massive blood loss, maternal hysterectomy, and preterm birth. Despite advancements in ultrasound protocols and found associations of alpha-fetoprotein, PAPP-A, hCG, PLGF, sFlt-1, IL-8, and IL-33 peripheral blood levels with PAS, there is a high need for an additional non-invasive test to improve the diagnostic accuracy and to select the real PAS from the suspected ones in the first-trimester screening. miRNA signatures of placental tissue, myometrium, and blood plasma from women with PAS in the third trimester of pregnancy, as well as miRNA profiles in exosomes from the blood serum of women in the first trimester with physiologically progressing pregnancy, complicated by PAS or pre-eclampsia, were obtained using deep sequencing. Two logistic regression models were constructed, both featuring statistically significant parameters related to the levels of miR-26a-5p, miR-17-5p, and miR-101-3p, quantified by real-time PCR in native blood serum. These models demonstrated 100% sensitivity in detecting PAS during the first pregnancy screening. These miRNAs were identified as specific markers for PAS, showing significant differences in their blood serum levels during the first trimester in the PAS group compared to those in physiological pregnancies, early- or late-onset pre-eclampsia groups. Furthermore, these miRNAs exhibited differential expression in the PAS placenta and/or myometrium in the third trimester and, according to data from the literature, control angiogenesis. Significant correlations were found between extracellular hsa-miR-101-3p and nuchal translucency thickness, hsa-miR-17-5p and uterine artery pulsatility index, and hsa-miR-26a-5p and hsa-miR-17-5p with PLGF. The developed test system for early non-invasive PAS diagnosis based on the blood serum level of extracellular miR-26a-5p, miR-17-5p, and miR-101-3p can serve as an auxiliary method for first-trimester screening of pregnant women, subject to validation with independent test samples.

Intraoperative temporary internal iliac arterial occlusion (Polat's technique) for severe placenta accreta spectrum: A description of the technique and outcomes in 61 patients

OBJECTIVE

To report the results of prophylactic use of intraoperative temporary internal iliac arterial occlusion by Bulldog clamps in patients clinically diagnosed with abnormally invasive placenta.

METHODS

This retrospective study included 61 patients diagnosed with FIGO grade 3 abnormally invasive placenta between January 2018 and March 2022. After transfundal incision and fetal delivery, bilateral temporary internal iliac arterial occlusion by Bulldog clamps was performed in all patients. The grades 3b and 3c group underwent cesarean hysterectomy whereas selected cases of grade 3a abnormally invasive placenta underwent fertility-preserving procedures. Preoperative and postoperative findings were compared.

RESULTS

Cesarean hysterectomy was performed in 50 (82%) patients and cesarean plus conservative procedures were performed in 11 (18%) patients. Intraoperative blood replacement was not performed in 83.6% of all patients. Mean blood loss was 1.37 ± 0.53 L (range 0.5-2.5) in all patients. Estimated blood loss was significantly higher in cesarean hysterectomy group. There was no statistically significant difference between two groups in terms of peroperative blood replacement, bladder, and ureteral injury.

CONCLUSION

Prophylactic bilateral temporary internal iliac arterial occlusion by Bulldog clamps should be performed in cases of grade 3 abnormally invasive placenta. Fertility-preserving steps may be undertaken safely in selected cases with this approach.

Society of Family Planning Clinical Recommendation: Management of hemorrhage at the time of abortion

Hemorrhage after abortion is rare, occurring in fewer than 1% of abortions, but associated morbidity may be significant. Although medication abortion is associated with more bleeding than procedural abortion, overall bleeding for the two methods is minimal and not clinically different. Hemorrhage can be caused by atony, coagulopathy, and abnormal placentation, as well as by such procedure complications as perforation, cervical laceration, and retained tissue. Evidence for practices around postabortion hemorrhage is extremely limited. The Society of Family Planning recommends preoperative identification of individuals at high risk of hemorrhage as well as development of an organized approach to treatment. Specifically, individuals with a uterine scar and complete placenta previa seeking abortion at gestations after the first trimester should be evaluated for placenta accreta spectrum. For those at high risk of hemorrhage, referral to a higher-acuity center should be considered. We propose an algorithm for treating postabortion hemorrhage as follows: (1) assessment and examination, (2) uterine massage and medical therapy, (3) resuscitative measures with laboratory evaluation and possible reaspiration or balloon tamponade, and (4) interventions such as embolization and surgery. Evidence supports the use of oxytocin as prophylaxis for bleeding with dilation and evacuation; methylergonovine prophylaxis, however, is associated with more bleeding at the time of dilation and evacuation. Future research is needed on tranexamic acid as prophylaxis and treatment and misoprostol as prophylaxis. Structural inequities contribute to bleeding risk. Acknowledging how our policies hinder or remedy health inequities is essential when developing new guidelines and approaches to clinical services.

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.

Balloon displacement during caesarean section with pernicious placenta previa: A case report

BACKGROUND

For the past few years, preventive interventional therapy has been widely used domestically and overseas, bringing great benefits to pregnant women at high-risk for complications, such as pernicious placenta previa (PPP) and placenta accreta. Nevertheless, there are still few reports on surgical complications related to interventional therapy, and its safety should be a concern.

CASE SUMMARY

We report a 36-year-old pregnant woman with PPP who underwent balloon implantation in the lower segment of the abdominal aorta before caesarean section. However, the balloon shifted during the operation, which damaged the arterial vessels after filling, resulting in severe postpartum haemorrhage in the patient. Fortunately, after emergency interventional stent implantation, the patient was successfully relieved of the massive haemorrhage crisis.

CONCLUSION

It seems that massive postoperative bleeding has been largely avoided in preventive interventional therapy in high-risk pregnant women with placenta-related diseases, but surgical complications related to intervention therapy can also cause adverse consequences. It is equally important for clinical doctors to learn how to promptly identify and effectively treat these rare complications.

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.

Tourniquet, Uterine Inversion, and Placental dissection （TURIP） procedure as a novel hemostatic technique to preserve fertility for placenta accreta spectrum disorders without placenta previa

The number of cases of placenta accreta spectrum disorder has been increasing with the increase in in vitro fertilization and cesarean deliveries. In addition, placenta accreta spectrum without placenta previa is difficult to diagnose before delivery and sometimes requires a hysterectomy because of heavy bleeding. We have devised a uterus-preserving technique (referred to as the tourniquet, uterine inversion, and placental dissection procedure) for such cases. First, the bleeding is stopped by the tourniquet method, the uterus is relaxed with nitroglycerin, and the uterus is inverted to expose the adhesion site. After that, the placenta is detached by sharp dissection under direct visualization, and the detached areas are sutured, and then the tourniquet and internal rotation are released. This technique does not require advanced skills. Thus, a surgeon could avoid performing a hysterectomy and have a greater chance of uterus preservation when encountering massive hemorrhage caused by unpredictable placenta accreta spectrum without placenta previa in either cesarean deliveries or vaginal deliveries.

Effects of COVID-19 home quarantine on pregnancy outcomes of patients with gestational diabetes mellitus: a retrospective cohort study

OBJECTIVE

This study aimed to evaluate the effects of the home quarantine on pregnancy outcomes of gestational diabetes mellitus (GDM) patients during the COVID-19 outbreak.

METHODS

The complete electronic medical records of patients with GDM with home quarantine history were collected and classified into the home quarantine group from 24 February 2020 to 24 November 2020. The same period of patients with GDM without home quarantine history were included in the control group from 2018 to 2019. The pregnant outcomes of the home quarantine and control groups were systematically compared, such as neonatal weight, head circumference, body length, one-minute Apgar score, fetal macrosomia, and pre-term delivery.

RESULTS

A total of 1358 patients with GDM were included in the analysis, including 484 in 2018, 468 in 2019, and 406 in 2020. Patients with GDM with home quarantine in 2020 had higher glycemic levels and adverse pregnancy outcomes than in 2018 and 2019, including higher cesarean section rates, lower Apgar scores, and higher incidence of macrosomia and umbilical cord around the neck. More importantly, the second trimester of home quarantine had brought a broader impact on pregnant women and fetuses.

CONCLUSION

Home quarantine has aggravated the condition of GDM pregnant women and brought more adverse pregnancy outcomes during the COVID-19 outbreak. Therefore, we suggested governments and hospitals strengthen lifestyle guidance, glucose management, and antenatal care for patients with GDM with home quarantine during public health emergencies.

Comparison of maternal outcomes and clinical characteristics of prenatally vs nonprenatally diagnosed placenta accreta spectrum: a systematic review and meta-analysis

OBJECTIVE

This study aimed to compare maternal outcomes of prenatally and nonprenatally diagnosed placenta accreta spectrum.

DATA SOURCES

A systematic literature search was performed in PubMed, the Cochrane database, and Web of Science until November 28, 2022.

STUDY ELIGIBILITY CRITERIA

Studies comparing the clinical presentation of prenatally and nonprenatally diagnosed placenta accreta spectrum were included. The primary outcomes were emergent cesarean delivery, hysterectomy, blood loss volume, number of transfused blood product units, urological injury, coagulopathy, reoperation, intensive care unit admission, and maternal death. In addition, the pooled mean values for blood loss volume and the number of transfused blood product units were calculated. The secondary outcomes included maternal age, gestational age at birth, nulliparity, previous cesarean delivery, previous uterine procedure, assisted reproductive technology, placenta increta and percreta, and placenta previa.

METHODS

Study screening was performed after duplicates were identified and removed. The quality of each study and the publication bias were assessed. Forest plots and I2 statistics were calculated for each study outcome for each group. The main analysis was a random-effects analysis.

RESULTS

Overall, 415 abstracts and 157 full-text studies were evaluated. Moreover, 31 studies were analyzed. Prenatally diagnosed placenta accreta spectrum was associated with a significantly lower rate of emergency cesarean delivery (odds ratio, 0.37; 95% confidence interval, 0.21-0.67), higher hysterectomy rate (odds ratio, 1.98; 95% confidence interval, 1.02-3.83), lower blood loss volume (mean difference, -0.65; 95% confidence interval, -1.17 to -0.13), and lower number of transfused red blood cell units (mean difference, -1.96; 95% confidence interval, -3.25 to -0.68) compared with nonprenatally diagnosed placenta accreta spectrum. The pooled mean values for blood loss volume and the number of transfused blood product units tended to be lower in the prenatally diagnosed placenta accreta spectrum groups than in the nonprenatally diagnosed placenta accreta spectrum groups. Nulliparity (odds ratio, 0.14; 95% confidence interval, 0.10-0.20), previous cesarean delivery (odds ratio, 6.81; 95% confidence interval, 4.12-11.25), assisted reproductive technology (odds ratio, 0.19; 95% confidence interval, 0.06-0.61), placenta increta and percreta (odds ratio, 3.97; 95% confidence interval, 2.24-7.03), and placenta previa (odds ratio, 6.81; 95% confidence interval, 4.12-11.25) showed statistical significance. No significant difference was found for the other outcomes.

CONCLUSION

Despite its severity, the positive effect of prenatally diagnosed placenta accreta spectrum on outcomes underscores the necessity of a prenatal diagnosis. In addition, the pooled mean values provide a preoperative preparation guideline.

Urological complications in women undergoing Cesarean section for placenta accreta spectrum disorders: systematic review and meta-analysis

OBJECTIVE

To report on the occurrence of urological complications in women undergoing Cesarean section for placenta accreta spectrum disorders (PAS).

METHODS

MEDLINE, EMBASE and the Cochrane databases were searched electronically up to 1 November 2022. Studies reporting on the urological outcome of women undergoing Cesarean section for PAS were included. Two independent reviewers performed data extraction using a predefined protocol and assessed the risk of bias using the Newcastle-Ottawa scale for observational studies, with disagreements resolved by consensus.The primary outcome was the overall occurrence of urological complications. Secondary outcomes were the occurrence of any cystotomy, intentional cystotomy, unintentional cystotomy, ureteral damage, ureteral fistula and vesicovaginal fistula. All outcomes were explored in the overall population of women undergoing surgery for PAS. In addition, we performed subgroup analyses according to the type of surgery (Cesarean hysterectomy, or conservative surgery or management), severity of PAS at histopathology (placenta accreta/increta and placenta percreta), type of intervention (planned vs emergency) and number of cases per year. Random-effects meta-analyses of proportions were used to analyze the data.

RESULTS

There were 62 studies included in the systematic review and 56 were included in the meta-analysis. Urological complications occurred in 15.2% (95% CI, 12.9-17.7%) of cases. Cystotomy complicated 13.5% (95% CI, 9.7-17.9%) of surgical operations. Intentional cystotomy was required in 7.7% (95% CI, 6.5-9.1%) of cases, while unintentional cystotomy occurred in 7.2% (95% CI, 6.0-8.5%) of cases. Urological complications occurred in 19.4% (95% CI, 16.3-22.7%) of cases undergoing hysterectomy and 12.2% (95% CI, 7.5-17.8%) of those undergoing conservative treatment. In the subgroup analyses, urological complications occurred in 9.4% (95% CI, 5.4-14.4%) of women with placenta accreta/increta and 38.5% (95% CI, 21.6-57.0%) of those described as having placenta percreta, and included mainly cystotomy (5.5% (95% CI, 0.6-15.1%) and 22.0% (95% CI, 5.4-45.5%), respectively). Urological complications occurred in 15.4% (95% CI, 8.1-24.6%) of cases undergoing a planned procedure and 24.6% (95% CI, 13.0-38.5%) of those undergoing an emergency intervention. In subanalysis of studies reporting on ≥ 12 cases per year, the incidence of urological complication was similar to that reported in the primary analysis.

CONCLUSIONS

Women undergoing surgery for PAS are at high risk of urological complication, mainly cystotomy. The incidence of these complications was particularly high in women described as having placenta percreta at birth and in those undergoing emergency surgical intervention. The high heterogeneity between the included studies highlights the need for a standardized protocol for the diagnosis of PAS to identify prenatal imaging signs associated with the increased risk of urological morbidity at delivery. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

The association of maternal obesity and obstetric anal sphincter injuries at time of vaginal delivery

BACKGROUND

The risk of third- and fourth-degree perineal laceration after vaginal delivery in patients with obesity is relatively understudied and has mixed findings in existing literature.

OBJECTIVE

This study aimed to examine the association of maternal obesity and obstetric anal sphincter injuries at vaginal delivery.

STUDY DESIGN

The Healthcare Cost and Utilization Project's National Inpatient Sample was retrospectively queried to examine 7,385,341 vaginal deliveries from January 2017 to December 2019. The exposure assignment was obesity status. The main outcomes were third- and fourth-degree perineal lacerations after vaginal delivery. Statistical analysis examining the exposure-outcome association included (1) inverse probability of treatment weighting with log-Poisson regression generalized linear model to account for prepregnant and pregnant confounders for the exposure and (2) multinomial regression model to account for delivery factors in the inverse probability of treatment weighting cohort. The secondary outcomes included (1) the temporal trends of fourth-degree laceration and its associated factors at cohort level and (2) risk factor patterns for fourth-degree laceration by constructing a classification tree model.

RESULTS

In the inverse probability of treatment weighting cohort, patients with obesity were less likely to have fourth-degree lacerations and third-degree lacerations than patients without obesity (fourth-degree laceration: 2.3 vs 3.9 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 0.62; 95% confidence interval, 0.56-0.69; third-degree laceration: 15.6 vs 20.1 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 0.79; 95% confidence interval, 0.76-0.82). In contrast, in patients with obesity vs those without obesity, forceps delivery (54.7 vs 3.3 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 17.73; 95% confidence interval, 16.17-19.44), vacuum-assisted delivery (19.8 vs 2.9 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 5.18; 95% confidence interval, 4.85-5.53), episiotomy (19.2 vs 2.8 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 3.95; 95% confidence interval, 3.71-4.20), and shoulder dystocia (17.8 vs 3.4 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 2.60; 95% confidence interval, 2.29-2.94) were associated with more than a 2-fold increased risk of fourth-degree perineal laceration. Among the group with obesity, patients who had forceps delivery and shoulder dystocia had the highest incidence of fourth-degree laceration (105.3 per 1000 vaginal deliveries). Among the group without obesity, patients who had forceps delivery, shoulder dystocia, and macrosomia had the highest incidence of fourth-degree laceration (294.1 per 1000 vaginal deliveries). The incidence of fourth-degree perineal laceration decreased by 11.9% over time (P trend=.004); moreover, forceps delivery, vacuum-assisted delivery, and episiotomy decreased by 3.8%, 7.6%, and 29.5%, respectively (all, P trend<.05).

CONCLUSION

This national-level analysis suggests that patients with obesity are less likely to have obstetric anal sphincter injuries at the time of vaginal delivery. Furthermore, this analysis confirms other known risk factors for fourth-degree laceration, such as forceps delivery, vacuum-assisted delivery, episiotomy, and shoulder dystocia. However, we noted a decreasing trend in fourth-degree lacerations, which may be due to evolving obstetrical practices.

Assessment of abnormal placentation in pregnancies conceived with assisted reproductive technology

OBJECTIVE

To examine the association between assisted reproductive technology (ART) and abnormal placentation.

METHODS

This is a retrospective cohort study querying the Healthcare Cost and Utilization Project's Nationwide Inpatient Sample. The study population included 14, 970, 064 deliveries for national estimates from January 2012 to September 2015. The exposure was 48, 240 pregnancies after ART. The main outcome measure encompassed three abnormal placentation pathologies (placenta previa [PP], placenta accreta spectrum [PAS], and vasa previa [VP]). Propensity score matching was performed to assess the exposure-outcome association.

RESULTS

Pregnancy after ART was more likely to have a diagnosis of PAS (2.8 vs 1.0 per 1000 deliveries; adjusted odds ratio [aOR], 2.06 [95% confidence interval (CI), 1.44-2.93]), PP (24.5 vs 8.6 per 1000; aOR, 2.98 [95% CI, 2.64-3.35]), and VP (2.3 vs <0.3 per 1000; aOR, 11.3 [95% CI, 5.86-21.8]) compared with pregnancy without ART. Similarly, pregnancy after ART was associated with an increased likelihood of having multiple types of abnormal placentation, including VP with PP (aOR, 15.4 [95% CI, 6.15-38.4]) and PAS with PP (aOR, 2.80 [95% CI, 1.32-5.92]) compared with non-ART pregnancy.

CONCLUSIONS

This national-level analysis suggests that pregnancy after ART is associated with a significantly increased risk of abnormal placentation, including PAS, PP, and VP.

Placenta Accreta Spectrum with Ureteral Invasion due to Progression of Cesarean Scar Pregnancy

Expectant management is not recommended for cesarean scar pregnancies because they are often associated with placenta accreta, cesarean hysterectomy, and massive life-threatening hemorrhages during delivery. Herein, we report a case of placenta accreta spectrum with ureteral invasion due to the progression of a cesarean scar pregnancy. Case. A 41-year-old woman, with a history of three cesarean sections and two miscarriages, was referred to our hospital at 25 weeks of gestation with a diagnosis of placenta accreta spectrum and bladder invasion. Although the gestational sac was located anterior to the lower uterine segment, a cesarean-scar pregnancy was not diagnosed. A cesarean hysterectomy was performed at 31 weeks of gestation with the placement of an aortic balloon. The placenta was found to adhere to the ureter with more than the expected parenchymal tissue displacement (FIGO Classification 3b). The ureter was not obstructed and was preserved by leaving the placenta slightly on the ureteral side. Postoperatively, a ureteral stent was placed because of the ureteral stricture in the area where the placenta had adhered. Two months after surgery, the ureteral stent was removed after observing an improvement in stenosis. An adherent placenta due to continued cesarean scar pregnancy should be managed by assuming placental invasion beyond the parenchyma into the ureter.

Placenta previa percreta with surrounding organ involvement: a proposal for management

Placenta accreta spectrum encompasses cases where the placenta is morbidly adherent to the myometrium. Placenta percreta, the most severe form of placenta accreta spectrum (grade 3E), occurs when the placenta invades through the myometrium and possibly into surrounding structures next to the uterine corpus. Maternal morbidity of placenta percreta is high, including severe maternal morbidity in 82.1% and mortality in 1.4% in the recent nationwide U.S. statistics. Although cesarean hysterectomy is commonly performed for patients with placenta accreta spectrum, conservative management is becoming more popular because of reduced morbidity in select cases. Treatment of grade 3E disease involving the urinary bladder, uterine cervix, or parametria is surgically complicated due to the location of the invasive placenta deep in the maternal pelvis. Cesarean hysterectomy in this setting has the potential for catastrophic hemorrhage and significant damage to surrounding organs. We propose a step-by-step schema to evaluate cases of grade 3E disease and determine whether immediate hysterectomy or conservative management, including planned delayed hysterectomy, is the most appropriate treatment option. The approach includes evaluation in the antenatal period with ultrasound and magnetic resonance imaging to determine suspicion for placenta previa percreta with surrounding organ involvement, planned cesarean delivery with a multidisciplinary team including experienced pelvic surgeons such as a gynecologic oncologist, intra-operative assessment including gross surgical field exposure and examination, cystoscopy, and consideration of careful intra-operative transvaginal ultrasound to determine the extent of placental invasion into surrounding organs. This evaluation helps decide the safety of primary cesarean hysterectomy. If safely resectable, additional considerations include intra-operative use of uterine artery embolization combined with tranexamic acid injection in cases at high risk for pelvic hemorrhage and ureteral stent placement. Availability of resuscitative endovascular balloon occlusion of the aorta is ideal. If safe resection is concerned, conservative management including planned delayed hysterectomy at around 4 weeks from cesarean delivery in stable patients is recommended.

Assessment of placenta accreta spectrum at vaginal birth after cesarean delivery

BACKGROUND

Previous cesarean delivery is a risk factor for developing placenta accreta spectrum in a subsequent pregnancy and patients with antenatally suspected placenta accreta spectrum frequently undergo planned cesarean hysterectomy. There is a paucity of data regarding unsuspected placenta accreta spectrum among patients undergoing trial of labor after cesarean delivery for attempted vaginal birth after cesarean delivery.

OBJECTIVE

This study aimed to investigate the incidence, characteristics, and delivery outcomes of patients with placenta accreta spectrum diagnosed at the time of vaginal birth after cesarean delivery.

STUDY DESIGN

The Healthcare Cost and Utilization Project's National Inpatient Sample was retrospectively queried to examine 184,415 patients with a history of low transverse cesarean delivery who had vaginal delivery in the current index hospital admission between 2017 and 2020. Those with placenta previa, previous vertical cesarean delivery, other uterine scars, and uterine rupture were excluded. This study identified placenta accreta spectrum cases using the World Health Organization International Classification of Disease, Tenth Revision, codes of O43.2. Coprimary outcomes were (1) the incidence rate of placenta accreta spectrum at vaginal birth after cesarean delivery; (2) clinical and pregnancy characteristics related to placenta accreta spectrum, assessed with multivariable binary logistic regression model; and (3) delivery outcomes associated with placenta accreta spectrum by fitting propensity score adjustment. The secondary outcome was to conduct a systematic literature review using 3 public search engines (PubMed, Cochrane, and Scopus). Data on incidence rate and maternal morbidity related to placenta accreta spectrum at vaginal birth after cesarean delivery were evaluated.

RESULTS

The incidence rate of placenta accreta spectrum at vaginal birth after cesarean delivery was 8.1 per 10,000 deliveries. Most placenta accreta spectrum cases were placenta accreta (83.3%). In a multivariable analysis, older maternal age, tobacco use, preeclampsia, multifetal pregnancy, fetal anomaly, preterm premature rupture of membrane, chorioamnionitis, low-lying placenta, and preterm delivery were associated with an increased risk of placenta accreta spectrum (all, P<.05). Of these factors, low-lying placenta had the largest odds for placenta accreta spectrum (526.3 vs 7.3 per 10,000 deliveries; adjusted odds ratio, 35.02; 95% confidence interval, 18.19-67.42). Patients in the placenta accreta spectrum group were more likely to have postpartum hemorrhage (80.0% vs 5.5%), blood product transfusion (23.3% vs 1.0%), shock or coagulopathy (20.0% vs 0.2%), and hysterectomy (43.3% vs <0.1%) than those without placenta accreta spectrum (all, P<.001). In a systematic literature review, a total of 212 studies were screened, and none of these studies examined the incidence and morbidity of placenta accreta spectrum at vaginal birth after cesarean delivery.

CONCLUSION

This nationwide assessment suggests that although placenta accreta spectrum with vaginal birth after cesarean delivery is uncommon (1 of 1229 cases), the diagnosis of placenta accreta spectrum at vaginal birth after cesarean delivery is associated with significant maternal morbidity. In addition, the data suggest that low-lying placenta in the setting of previous low transverse cesarean delivery warrants careful evaluation for possible placenta accreta spectrum before a trial of labor.

Pregnancy with retained intrauterine device: national-level assessment of characteristics and outcomes

BACKGROUND

Although intrauterine devices provide effective contraceptive protection, unintentional pregnancy can occur. Previous studies have shown that a retained intrauterine device during pregnancy is associated with adverse pregnancy outcomes but there is a paucity of nationwide data and analysis.

OBJECTIVE

This study aimed to describe characteristics and outcomes of pregnancies with a retained intrauterine device.

STUDY DESIGN

This serial cross-sectional study used data from the Healthcare Cost and Utilization Project's National Inpatient Sample. The study population comprised 18,067,310 hospital deliveries for national estimates from January 2016 to December 2020. The exposure was retained intrauterine device status, identified by the World Health Organization's International Classification of Diseases, Tenth Revision, code O26.3. The co-primary outcome measures were incidence rate, clinical and pregnancy characteristics, and delivery outcome of patients with a retained intrauterine device. To assess the pregnancy characteristics and delivery outcomes, an inverse probability of treatment weighting cohort was created to mitigate the prepregnant confounders for a retain intrauterine device.

RESULTS

A retained intrauterine device was reported in 1 in 8307 hospital deliveries (12.0 per 100,000). In a multivariable analysis, Hispanic individuals, grand multiparity, obesity, alcohol use, and a previous uterine scar were patient characteristics associated with a retained intrauterine device (all P<.05). Current pregnancy characteristics associated with a retained intrauterine device included preterm premature rupture of membrane (9.2% vs 2.7%; adjusted odds ratio, 3.15; 95% confidence interval, 2.41-4.12), fetal malpresentation (10.9% vs 7.2%; adjusted odds ratio, 1.47; 95% confidence interval, 1.15-1.88), fetal anomaly (2.2% vs 1.1%; adjusted odds ratio, 1.71; 95% confidence interval, 1.03-2.85), intrauterine fetal demise (2.6% vs 0.8%; adjusted odds ratio, 2.21; 95% confidence interval, 1.37-3.57), placenta malformation (1.8% vs 0.8%; adjusted odds ratio, 2.12; 95% confidence interval, 1.20-3.76), placenta abruption (4.7% vs 1.1%; adjusted odds ratio, 3.24; 95% confidence interval, 2.25-4.66), and placenta accreta spectrum (0.7% vs 0.1%; adjusted odds ratio, 4.82; 95% confidence interval, 1.99-11.65). Delivery characteristics associated with a retained intrauterine device included previable loss at <22 weeks' gestation (3.4% vs 0.3%; adjusted odds ratio, 5.49; 95% confidence interval, 3.30-9.15) and periviable delivery at 22 to 25 weeks' gestation (3.1% vs 0.5%; adjusted odds ratio, 2.81; 95% confidence interval, 1.63-4.86). Patients in the retained intrauterine device group were more likely to have a diagnosis of retained placenta at delivery (2.5% vs 0.4%; adjusted odds ratio, 4.45; 95% confidence interval, 2.70-7.36) and to undergo manual placental removal (3.2% vs 0.6%; adjusted odds ratio, 4.81; 95% confidence interval, 3.11-7.44).

CONCLUSION

This nationwide analysis confirmed that pregnancy with a retained intrauterine device is uncommon, but these pregnancies may be associated with high-risk pregnancy characteristics and outcomes.

Pathologically diagnosed placenta accreta spectrum without placenta previa: a systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis aimed to assess clinical characteristics related to pathologically proven placenta accreta spectrum without placenta previa.

DATA SOURCES

A literature search of PubMed, the Cochrane database, and Web of Science was performed from inception to September 7, 2022.

STUDY ELIGIBILITY CRITERIA

The primary outcomes were invasive placenta (including increta or percreta), blood loss, hysterectomy, and antenatal diagnosis. In addition, maternal age, assisted reproductive technology, previous cesarean delivery, and previous uterine procedures were investigated as potential risk factors. The inclusion criteria were studies evaluating the clinical presentation of pathologically diagnosed PAS without placenta previa.

METHODS

Study screening was conducted after duplicates were identified and removed. The quality of each study and the publication bias were assessed. Forest plots and I2 statistics were calculated for each study outcome for each group. The main analysis was a random-effects analysis.

RESULTS

Among 2598 studies that were initially retrieved, 5 were included in the review. With the exception of 1 study, 4 studies were included in the meta-analysis. This meta-analysis showed that placenta accreta spectrum without placenta previa was associated with less risk of invasive placenta (odds ratio, 0.24; 95% confidence interval, 0.16-0.37), blood loss (mean difference, -1.19; 95% confidence interval, -2.09 to -0.28) and hysterectomy (odds ratio, 0.11; 95% confidence interval, 0.02-0.53), and more difficult to diagnose prenatally (odds ratio, 0.13; 95% confidence interval, 0.04-0.45) than placenta accreta spectrum with placenta previa. In addition, assisted reproductive technology and a previous uterine procedure were strong risk factors for placenta accreta spectrum without placenta previa, whhereas previous cesarean delivery was a strong risk factor for placenta accreta spectrum with placenta previa.

CONCLUSION

The differences in clinical aspects of placenta accreta spectrum with and without placenta previa need to be understood.

Incidence, characteristics, and maternal outcomes of pregnancy with uterine prolapse

BACKGROUND

Gravid uterine prolapse refers to abnormal descent of the uterus during pregnancy. It is a rare pregnancy complication and its clinical characteristics and obstetrical outcomes are not well understood.

OBJECTIVE

This study aimed to assess the national-level incidence, characteristics, and maternal outcomes of pregnancies complicated by gravid uterine prolapse.

STUDY DESIGN

This retrospective cohort study queried the Healthcare Cost and Utilization Project's National Inpatient Sample. The study population was 14,647,670 deliveries from January 2016 to December 2019. The exposure assignment was the diagnosis of uterine prolapse. The coprimary outcome measures were incidence rate, clinical and pregnancy characteristics, and delivery outcomes of patients with gravid uterine prolapse. The inverse probability of treatment weighting cohort was created to mitigate the difference in prepregnancy confounding factors, followed by adjusting for pregnancy and delivery factors.

RESULTS

The incidence of gravid uterine prolapse was 1 in 4209 deliveries (23.8 per 100,000). In a multivariable analysis, older age (≥40 years; adjusted odds ratio, 3.21; 95% confidence interval, 2.70-3.81); age from 35 to 39 years (adjusted odds ratio, 2.66; 95% confidence interval, 2.37-2.99); Black (adjusted odds ratio, 1.48; 95% confidence interval, 1.34-1.63), Asian (adjusted odds ratio, 1.45; 95% confidence interval, 1.28-1.64), and Native American (adjusted odds ratio, 2.17; 95% confidence interval, 1.63-2.88) race/ethnicity; tobacco use (adjusted odds ratio, 1.19; 95% confidence interval, 1.03-1.37); grand multiparity (adjusted odds ratio, 1.78; 95% confidence interval, 1.24-2.55); and history of pregnancy losses (adjusted odds ratio, 2.20; 95% confidence interval, 1.48-3.26) were the patient characteristics associated with increased risk of gravid uterine prolapse. Current pregnancy characteristics associated with gravid uterine prolapse included cervical insufficiency (adjusted odds ratio, 3.25; 95% confidence interval, 1.94-5.45), preterm labor (adjusted odds ratio, 1.53; 95% confidence interval, 1.18-1.97), preterm premature rupture of membranes (adjusted odds ratio, 1.40; 95% confidence interval, 1.01-1.94), and chorioamnionitis (adjusted odds ratio, 1.64; 95% confidence interval, 1.18-2.28). Delivery characteristics associated with gravid uterine prolapse included early-preterm delivery at <34 weeks' gestation (69.1 vs 32.0 per 1000; adjusted odds ratio, 1.86; 95% confidence interval, 1.34-2.59) and precipitate labor (35.2 vs 20.1; adjusted odds ratio, 1.73; 95% confidence interval, 1.22-2.44). Moreover, risks of postpartum hemorrhage (112.1 vs 44.4 per 1000; adjusted odds ratio, 2.70; 95% confidence interval, 2.20-3.32), uterine atony (32.0 vs 15.7; adjusted odds ratio, 2.10; 95% confidence interval, 1.46-3.03), uterine inversion (9.6 vs 0.3; adjusted odds ratio, 31.97; 95% confidence interval, 16.60-61.58), shock (3.2 vs 0.7; adjusted odds ratio, 4.18; 95% confidence interval, 1.41-12.40), blood product transfusion (22.4 vs 11.1; adjusted odds ratio, 2.06; 95% confidence interval, 1.34-3.18), and hysterectomy (7.5 vs 2.3; adjusted odds ratio, 3.02; 95% confidence interval, 1.40-6.51) were increased in the gravid uterine prolapse group compared with the nonprolapse group. Conversely, patients with gravid uterine prolapse were less likely to deliver via cesarean delivery compared with those without gravid uterine prolapse (200.6 vs 322.8 per 1000; adjusted odds ratio, 0.51; 95% confidence interval, 0.44-0.61).

CONCLUSION

This nationwide analysis suggests that pregnancy with gravid uterine prolapse is uncommon but associated with several high-risk pregnancy characteristics and adverse delivery outcomes.

Recent trends in term trial of labor after cesarean by number of prior cesarean deliveries

BACKGROUND

Cesarean delivery is a major source of maternal morbidity, and repeat cesarean delivery accounts for 40% of cesarean delivery, but recent data on the trial of labor after cesarean and vaginal birth after cesarean are limited.

OBJECTIVE

This study aimed to report the national rates of trial of labor after cesarean and vaginal birth after cesarean by number of previous cesarean deliveries and examine the effect of demographic and clinical characteristics on these rates.

STUDY DESIGN

This was a population-based cohort study using the US natality data files. The study sample was restricted to 4,135,247 nonanomalous singleton, cephalic deliveries between 37 and 42 weeks of gestation, with a history of previous cesarean delivery and delivered in a hospital between 2010 and 2019. Deliveries were grouped by number of previous cesarean deliveries (1, 2, or ≥3). The trial of labor after cesarean (deliveries with labor among deliveries with previous cesarean delivery) and vaginal birth after cesarean (vaginal deliveries among trial of labor after cesarean) rates were computed for each year. The rates were further subgrouped by history of previous vaginal delivery. Year of delivery, number of previous cesarean deliveries, history of previous cesarean delivery, age, race and ethnicity, maternal education, obesity, diabetes mellitus, hypertension, inadequate prenatal care, Medicaid payer, and gestational age were examined concerning the trial of labor after cesarean and vaginal birth after cesarean using multiple logistic regression. SAS software (version 9.4) was used for all analyses.

RESULTS

The trial of labor after cesarean rates increased from 14.4% in 2010 to 19.6% in 2019 (P<.001). This trend was seen in all categories of number of previous cesarean deliveries. Moreover, vaginal birth after cesarean rates increased from 68.5% in 2010 to 74.3% in 2019. The trial of labor after cesarean and vaginal birth after cesarean rates were the highest for deliveries with a history of both 1 previous cesarean delivery and a vaginal delivery (28.9% and 79.7%, respectively) and the lowest for those with a history of ≥3 previous cesarean deliveries and no history of vaginal delivery (4.5% and 46.9%, respectively). Factors associated with the trial of labor after cesarean and vaginal birth after cesarean rates are similar, but several factors have different directions of effect, such as non-White race and ethnicity, which is associated with a higher likelihood of trial of labor after cesarean but a lower likelihood of successful vaginal birth after cesarean.

CONCLUSION

More than 80% of patients with a history of previous cesarean delivery deliver by repeat scheduled cesarean delivery. With vaginal birth after cesarean rates increasing among those who attempt a trial of labor after cesarean, emphasis should be put on safely increasing the trial of labor after cesarean rates.

Trends, Characteristics, and Maternal Morbidity Associated With Unhoused Status in Pregnancy

Importance

Unhoused status is a substantial problem in the US. Pregnancy characteristics and maternal outcomes of individuals experiencing homelessness are currently under active investigation to optimize health outcomes for this population.

Objective

To assess the trends, characteristics, and maternal outcomes associated with unhoused status in pregnancy.

Design, Setting, and Participants

This cross-sectional study analyzed data from the Healthcare Cost and Utilization Project National (Nationwide) Inpatient Sample. The study population included hospitalizations for vaginal and cesarean deliveries from January 1, 2016, to December 31, 2020. Unhoused status of these patients was identified from use of International Statistical Classification of Diseases, Tenth Revision, Clinical Modification code Z59.0. Statistical analysis was conducted from December 2022 to June 2023.

Main Outcomes and Measures

Primary outcomes were (1) temporal trends; (2) patient and pregnancy characteristics associated with unhoused status, which were assessed with a multivariable logistic regression model; (3) delivery outcomes, including severe maternal morbidity (SMM) and mortality at delivery, which used the Centers for Disease Control and Prevention definition for SMM indicators and were assessed with a propensity score-adjusted model; and (4) choice of long-acting reversible contraception method and surgical sterilization at delivery.

Results

A total of 18 076 440 hospital deliveries were included, of which 18 970 involved pregnant patients who were experiencing homelessness at the time of delivery, for a prevalence rate of 104.9 per 100 000 hospital deliveries. These patients had a median (IQR) age of 29 (25-33) years. The prevalence of unhoused patients increased by 72.1% over a 5-year period from 76.1 in 2016 to 131.0 in 2020 per 100 000 deliveries (P for trend < .001). This association remained independent in multivariable analysis. In addition, (1) substance use disorder (tobacco, illicit drugs, and alcohol use disorder), (2) mental health conditions (schizophrenia, bipolar, depressive, and anxiety disorders, including suicidal ideation and past suicide attempt), (3) infectious diseases (hepatitis, gonorrhea, syphilis, herpes, and COVID-19), (4) patient characteristics (Black and Native American race and ethnicity, younger and older age, low or unknown household income, obesity, pregestational hypertension, pregestational diabetes, and asthma), and (5) pregnancy characteristics (prior uterine scar, excess weight gain during pregnancy, and preeclampsia) were associated with unhoused status in pregnancy. Unhoused status was associated with extreme preterm delivery (<28-week gestation: 34.3 vs 10.8 per 1000 deliveries; adjusted odds ratio [AOR], 2.76 [95% CI, 2.55-2.99]); SMM at in-hospital delivery (any morbidity: 53.8 vs 17.7 per 1000 deliveries; AOR, 2.30 [95% CI, 2.15-2.45]); and in-hospital mortality (0.8 vs <0.1 per 1000 deliveries; AOR, 10.17 [95% CI, 6.10-16.94]), including case fatality risk after SMM (1.5% vs 0.3%; AOR, 4.46 [95% CI, 2.67-7.45]). Individual morbidity indicators associated with unhoused status included cardiac arrest (AOR, 12.43; 95% CI, 8.66-17.85), cardiac rhythm conversion (AOR, 6.62; 95% CI, 3.98-11.01), ventilation (AOR, 6.24; 95% CI, 5.03-7.74), and sepsis (AOR, 5.37; 95% CI, 4.53-6.36).

Conclusions and Relevance

Results of this national cross-sectional study suggest that unhoused status in pregnancy gradually increased in the US during the 5-year study period and that pregnant patients with unhoused status were a high-risk pregnancy group.

Efficacy of resuscitative endovascular balloon occlusion of the aorta for hemorrhage control in patients with abnormally invasive placenta: a historical cohort study

BACKGROUND

Patients with abnormally invasive placenta (AIP) are at high risk of massive postpartum hemorrhage. Resuscitative endovascular balloon occlusion of the aorta (REBOA), as an adjunct therapeutic strategy for hemostasis, offers the obstetrician an alternative for treating patients with AIP. This study aimed to evaluate the role of REBOA in hemorrhage control in patients with AIP.

METHODS

This was a historical cohort study with prospectively collected data between January 2014 to July 2021 at a single tertiary center. According to delivery management, 364 singleton pregnant AIP patients desiring uterus preservation were separated into two groups. The study group (balloon group, n = 278) underwent REBOA during cesarean section, whereas the reference group (n = 86) did not undergo REBOA. Surgical details and maternal outcomes were collected. The primary outcome was estimated blood loss and the rate of uterine preservation.

RESULTS

A total of 278 (76.4%) participants experienced REBOA during cesarean section. The patients in the balloon group had a smaller blood loss during cesarean Sect. (1370.5 [752.0] ml vs. 3536.8 [1383.2] ml; P < .001) and had their uterus salvaged more often (264 [95.0%] vs. 23 [26.7%]; P < .001). These patients were also less likely to be admitted to the intensive care unit after delivery (168 [60.4%] vs. 67 [77.9%]; P = .003) and had a shorter operating time (96.3 [37.6] min vs. 160.6 [45.5] min; P < .001). The rate of neonatal intensive care unit admission (176 [63.3%] vs. 52 [60.4%]; P = .70) and total maternal medical costs ($4925.4 [1740.7] vs. $5083.2 [1705.1]; P = .13) did not differ between the two groups.

CONCLUSIONS

As a robust hemorrhage-control technique, REBOA can reduce intraoperative hemorrhage in patients with AIP. The next step is identifying associated risk factors and defining REBOA inclusion criteria to identify the subgroups of AIP patients who may benefit more.