Placenta accreta: risk factors, perinatal outcomes, and consequences for subsequent births

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

OBJECTIVE

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

STUDY DESIGN

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

RESULTS

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

CONCLUSION

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

KEY POINTS

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

Delivery outcomes in the subsequent pregnancy following the conservative management of placenta accreta spectrum disorder: a systematic review and meta-analysis

OBJECTIVE

Cesarean hysterectomy is generally presumed to decrease maternal morbidity and mortality secondary to placenta accreta spectrum disorder. Recently, uterine-sparing techniques have been introduced in conservative management of placenta accreta spectrum disorder to preserve fertility and potentially reduce surgical complications. However, despite patients often expressing the intention for future conception, few data are available regarding the subsequent pregnancy outcomes after conservative management of placenta accreta spectrum disorder. Thus, we aimed to perform a systematic review and meta-analysis to assess these outcomes.

DATA SOURCES

PubMed, Scopus, and Web of Science databases were searched from inception to September 2022.

STUDY ELIGIBILITY CRITERIA

We included all studies, with the exception of case studies, that reported the first subsequent pregnancy outcomes in individuals with a history of placenta accreta spectrum disorder who underwent any type of conservative management.

METHODS

The R programming language with the "meta" package was used. The random-effects model and inverse variance method were used to pool the proportion of pregnancy outcomes.

RESULTS

We identified 5 studies involving 1458 participants that were eligible for quantitative synthesis. The type of conservative management included placenta left in situ (n=1) and resection surgery (n=1), and was not reported in 3 studies. The rate of placenta accreta spectrum disorder recurrence in the subsequent pregnancy was 11.8% (95% confidence interval, 1.1-60.3; I2=86.4%), and 1.9% (95% confidence interval, 0.0-34.1; I2=82.4%) of participants underwent cesarean hysterectomy. Postpartum hemorrhage occurred in 10.3% (95% confidence interval, 0.3-81.4; I2=96.7%). A composite adverse maternal outcome was reported in 22.7% of participants (95% confidence interval, 0.0-99.4; I2=56.3%).

CONCLUSION

Favorable pregnancy outcome is possible following successful conservation of the uterus in a placenta accreta spectrum disorder pregnancy. Approximately 1 out of 4 subsequent pregnancies following conservative management of placenta accreta spectrum disorder had considerable adverse maternal outcomes. Given such high incidence of adverse outcomes and morbidity, patient and provider preparation is vital when managing this population.

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

BACKGROUND

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

OBJECTIVES

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

SEARCH STRATEGY

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

CONCLUSION

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

[French survey on the management strategy for placenta accreta spectrum]

OBJECTIVE

Placenta accreta belongs to placenta accreta spectrum and is defined by an adhesion or even invasion of the placental villi in the myometrium. The main risk factor is a history of cesarean section. Its incidence is increasing following an increase in the cesarean section rate in recent years and the cause of severe maternal morbidity (hemorrhage, transfusions, hysterectomy). Treatment can be radical by cesarean section-hysterectomy or conservative with an attempt at uterine preservation. American, English, Canadian and international recommendations have been established but there are no French recommendations to date. The objective of this study was to investigate management strategy for placenta accreta in type III maternity hospitals in France.

MATERIALS AND METHODS

An anonymous questionnaire was sent by email to the obstetrics referents of the university hospital centers in France with type III maternity.

RESULTS

Forty-eight centers were approached, with a participation rate of 77%.

CONCLUSION

The management of placenta accreta spectrum in France is relatively heterogeneous on several points such as multidisciplinary management, evaluation by placental MRI, preoperative urological evaluation, treatment adopted as first-line, cesarean section-hysterectomy or conservative treatment, therapeutic strategy according to the placental invasion. However, the literature is currently poor, which may explain divergent treatment.

The impact of a previous cesarean section on the risk of perioperative and postoperative complications during vaginal hysterectomy

OBJECTIVE

To investigate whether a previous cesarean section increases the risk of perioperative and postoperative complications during vaginal hysterectomy.

METHODS

A retrospective cohort study of women who had undergone a vaginal hysterectomy for benign indications between 2014 and 2019 was conducted, comparing patients with or without a previous cesarean section. Perioperative and postoperative complications during vaginal hysterectomy were assessed according to the Clavien-Dindo classification system within 30 days of surgery. Duration of surgery, estimated blood loss, and postoperative hospitalization days were also recorded. A two-sided P value of less than 0.05 was considered significant.

RESULTS

A total of 185 women were included, 25 (13.5%) patients had undergone a previous cesarean section (study group) and 160 (86.5%) had no history of cesarean section (comparison group). We found no significant differences in demographic and clinical characteristics as well as postoperative complications and interventions, duration of surgery, estimated blood loss, and postoperative hospitalization days (P > 0.05). However, patients who underwent two or more cesarean sections had a significantly (P = 0.01) higher rate and grade of complications during vaginal hysterectomy, compared with women with only one previous cesarean section. All women who underwent two or more cesarean sections had mild complications during vaginal hysterectomy (40% grade I and 60% grade II, P = 0.01).

CONCLUSION

Vaginal hysterectomy is a safe procedure with few severe complications, regardless of a previous cesarean section. More than one previous cesarean section may increase the risk of minor complications during a vaginal hysterectomy. Patients who underwent a previous cesarean section could be reassured that they do not face an increased risk of complications during a vaginal hysterectomy.

Placental volume as a novel sign for identifying placenta accreta spectrum in pregnancies with complete placenta previa

BACKGROUND

Placenta accreta spectrum (PAS) carries an increased risk of maternal-fetal mortality and morbidity, and magnetic resonance imaging (MRI) features for PAS have been used for preoperative identification. This study aims to investigate the role of placental volume evaluated by MRI in identifying PAS in pregnant women with complete placenta previa.

METHODS

Totally 163 cases of complete placenta previa pregnant women with a history of cesarean section underwent MRI for suspected PAS were included. We categorized the patients into two groups according to the presence or absence of PAS, and the maternal-fetal perinatal outcomes and placental volume analyzed by 3D Slice software were compared.

RESULTS

There were significantly more gravidity, parity, and number of previous cesarean delivery in the PAS group (P < 0.05). Significant differences were also found between the two groups with respect to the following baseline characteristics: gestational age at delivery, intraoperative blood loss, blood transfusion, and neonatal birth weight (P < 0.05). Of 163 women in the study, 7 (4.294%) required cesarean hysterectomy for high-grade PAS or pernicious bleeding during cesarean section, and PAS was confirmed with histologic confirmation in 6 (85.714%) cases. The placental volume in PAS group was greater than that in the non-PAS group (P < 0.05). With a threshold of more than 887 cm3, the sensitivity and specificity in identifying PAS were 85.531% and 83.907% respectively, with AUC 0.908 (95% CI: 0.853-0.948).

CONCLUSIONS

Placental volume may be a promising indicator of PAS in complete placenta previa patients with a history of cesarean section.

Placenta Accreta Spectrum Prophylactic Therapy for Hyperfibrinolysis with Tranexamic Acid

BACKGROUND

To report on prophylactic therapy for hyperfibrinolysis with tranexamic acid (TXA) during expectant management (EM) in the placenta accreta spectrum (PAS).

METHODS

This is a monocentric retrospective study of women with PAS presenting at our hospital between 2005 and 2021. All data were retrospectively collected through the departmental database.

RESULTS

35 patients with PAS were included. EM was planned in 25 patients prior to delivery. Complete absorption of the retained placenta was seen in two patients (8%). Curettage was performed in 14 patients (56%). A hysterectomy (HE) was needed in seven (28%) patients; 18 patients (72%) underwent uterus-preserving treatment without severe complications. The mean duration of EM was 107 days. The mean day of onset of hyperfibrinolysis and beginning of TXA treatment was day 45. The mean nadir of fibrinogen level before TXA was 242.4 mg/dL, with a mean drop of 29.7% in fibrinogen level.

CONCLUSIONS

Our data support EM as a safe treatment option in PAS. Hyperfibrinolysis can be a cause of hemorrhage during EM and can be treated with TXA. To our knowledge, this is the first cohort of patients with EM of PAS in whom coagulation monitoring and use of TXA have been shown to successfully treat hyperfibrinolysis.

Subsequent pregnancy outcomes and risk factors following conservative treatment for placenta accreta spectrum: a retrospective cohort study

BACKGROUND

Placenta accreta spectrum can lead to uncontrollable massive hemorrhage in the perinatal period. Currently, the first-line treatment for placenta accreta spectrum recommended worldwide is hysterectomy. However, adverse outcomes after hysterectomy, including surgical complications, such as difficulty in performing the procedure, and sequelae, such as infertility and psychological issues, cannot be ignored. Several surgical approaches for conservative treatment have been proposed. There are few reports on the effectiveness, safety, and long-term complications of conservative treatments, especially subsequent pregnancy outcomes.

OBJECTIVE

This study aimed to investigate the clinical outcomes and identify risk factors of subsequent pregnancies among patients with placenta accreta spectrum who had undergone conservative surgery.

STUDY DESIGN

This was a retrospective cohort study of subsequent pregnancy cases after cesarean delivery with conservative treatment for placenta accreta spectrum from 2011 to 2019 at The First Affiliated Hospital of Zhengzhou University to identify clinical outcomes of subsequent pregnancies and the risk factors of adverse pregnancy outcomes.

RESULTS

A total of 883 patients undergoing conservative surgery were included in this study, among which 604 (68.4%) were successfully followed up. There were 75 successful pregnancies in 72 patients, including 22 full-term or near-term deliveries, 1 induced labor in the second trimester of pregnancy, 6 cesarean scar pregnancies (8.0%), 2 ectopic pregnancies, and 44 first-trimester pregnancies (3 miscarriages and 41 elective abortions and 12 medical abortions and 32 vacuum aspirations). All newborns survived in the 22 full-term or near-term deliveries. Moreover, 5 placenta accreta spectrum cases (22.7%) and 6 placenta previa cases were observed. Postpartum hemorrhage was observed in 2 cases, with an incidence rate of 9.1%. All parameters, including age at subsequent pregnancy, gravidity, number of cesarean deliveries, type of previous placenta accreta spectrum, gestational week of pregnancy termination, interpregnancy interval, and the use of vascular occlusion techniques, were not found to be associated with recurrent placenta accreta spectrum and cesarean scar pregnancy.

CONCLUSION

Our findings show that treatment for placenta accreta spectrum does not automatically preclude a subsequent pregnancy. However, patients should be fully informed about the risk of recurrent placenta accreta spectrum, scar pregnancy, and postpartum hemorrhage.

Use of super resolution reconstruction MRI for surgical planning in Placenta accreta spectrum disorder: Case series

INTRODUCTION

Comprehensive imaging using ultrasound and MRI of placenta accreta spectrum (PAS) aims to prevent catastrophic haemorrhage and maternal death. Standard MRI of the placenta is limited by between-slice motion which can be mitigated by super-resolution reconstruction (SRR) MRI. We applied SRR in suspected PAS cases to determine its ability to enhance anatomical placental assessment and predict adverse maternal outcome.

METHODS

Suspected PAS patients (n = 22) underwent MRI at a gestational age (weeks + days) of (32+3±3+2, range (27+1-38+6)). SRR of the placental-myometrial-bladder interface involving rigid motion correction of acquired MRI slices combined with robust outlier detection to reconstruct an isotropic high-resolution volume, was achieved in twelve. 2D MRI or SRR images alone, and paired data were assessed by four radiologists in three review rounds. All radiologists were blinded to results of the ultrasound, original MR image reports, case outcomes, and PAS diagnosis. A Random Forest Classification model was used to highlight the most predictive pathological MRI markers for major obstetric haemorrhage (MOH), bladder adherence (BA), and placental attachment depth (PAD).

RESULTS

At delivery, four patients had placenta praevia with no abnormal attachment, two were clinically diagnosed with PAS, and six had histopathological PAS confirmation. Pathological MRI markers (T2-dark intraplacental bands, and loss of retroplacental T2-hypointense line) predicting MOH were more visible using SRR imaging (accuracy 0.73), in comparison to 2D MRI or paired imaging. Bladder wall interruption, predicting BA, was only easily detected by paired imaging (accuracy 0.72). Better detection of certain pathological markers predicting PAD was found using 2D MRI (placental bulge and myometrial thinning (accuracy 0.81)), and SRR (loss of retroplacental T2-hypointense line (accuracy 0.82)).

DISCUSSION

The addition of SRR to 2D MRI potentially improved anatomical assessment of certain pathological MRI markers of abnormal placentation that predict maternal morbidity which may benefit surgical planning.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

CLINICAL TRIAL REGISTRATION NUMBER

ChiCTR2000035202.

Knowledge Gaps in Placenta Accreta Spectrum

Since its first description early in the 20th Century, placenta accreta and its variants have changed substantially in incidence, risk factor profile, clinical presentation, diagnosis and management. While systematic use of diagnostic tools and a multidisciplinary team care approach has begun to improve patient outcomes, the condition's pathophysiology, epidemiology, and best practices for diagnosis and management remain poorly understood. The use of large databases with broadly accepted terminology and diagnostic criteria should accelerate research in this area. Future work should focus on non-traditional phenotypes, such as those without placenta previa-preventive strategies, and long term medical and emotional support for patients facing this diagnosis. KEY POINTS: · Placenta accreta spectrum research may be improved with standardized terminology and use of large databases.. · Placenta accreta prediction should move beyond ultrasound with the addition of biomarkers, and needs to extend to those without traditional risk factors.. · Future research should identify practices that can prevent future accreta development..

Placenta accreta spectrum in major placenta previa diagnosed only by MRI: incidence, risk factors, and maternal morbidity

BACKGROUND

Antenatal assessment of maternal risk factors and imaging evaluation can help in diagnosis and treatment of placenta accreta spectrum (PAS) in major placenta previa (PP). Recent evidence suggests that magnetic resonance imaging (MRI) could complement ultrasonography (US) in the PAS diagnosis.

OBJECTIVES

Evaluate the incidence, risk factors, and maternal morbidity related to the MRI diagnosis of PAS in major PP.

DESIGN

A 10-year retrospective cohort study.

SETTING

Tertiary care hospital.

PATIENTS AND METHODS

We report on patients with major PP who had cesarean delivery in Abha Maternity and Children's Hospital (AMCH) over a 10-year period (2012-2021). They were evaluated with ultrasonography (US) and color Doppler for evidence of PAS. Antenatal MRI was ordered either to confirm the diagnosis (if equivocal US) or to assess the depth of invasion/extra-uterine extension (if definitive US).

MAIN OUTCOME MEASURES

Risk factors for PAS in major PP and maternal complications.

SAMPLE SIZE

299 patients RESULTS: Among 299 patients, MRI confirmed the PAS diagnosis in 91/299 (30.5%) patients. The independent risk factors for MRI diagnosis of PAS in major PP included only repeated cesarean sections and advanced maternal age. The commonest maternal morbidity in major PP with PAS was significantly excessive intraoperative bleeding.

CONCLUSION

MRI may be a valuable adjunct in the evaluation of PAS in major PP; as a complement, but not substitute US. MRI may be suitable in major PP/PAS patients who are older and have repeated cesarean deliveries with equivocal results or deep/extra-uterine extension on US.

LIMITATION

Single center, small sample size, lack of complete histopathological diagnosis.

CONFLICT OF INTEREST

None.

Effect of placenta location detected by ultrasound on the severity of placenta accreta spectrum in patients with placenta previa and placenta accreta spectrum

BACKGROUND

To evaluate the effect of placental location on the severity of placenta accreta spectrum (PAS).

METHODS

We analyzed 390 patients with placenta previa combined with placenta accreta spectrum who underwent cesarean section between January 1, 2014 and December 30, 2020 in the electronic case database of the Second Hospital of Hebei Medical University. According to the position of the placenta, 390 placentas were divided into the posterior group (n = 89), the anterior group (n = 60) and the non-central group (n = 241).

RESULTS

The history of cesarean delivery rates in the anterior group (91.67%) and the non-central group (85.71%) were statistically different from the posterior group (63.74%)(P < 0.001). Univariate logistic regression results showed that employment, urban living, gestational age, complete placenta previa, fetal presentation shoulder, gravidity, cesarean section and vaginal delivery were all predictors for the severity of placenta accreta (P < 0.05). The anterior group (P = 0.001, OR = 4.13, 95%CI: 1.84-9.24) and the non-central group (P = 0.001, OR = 2.90, 95%CI: 1.55-5.45) had a higher incidence of invasive accreta placentation than the posterior group, and were independent risk factors for invasive accreta placentation.

CONCLUSION

Compared with posterior placenta, anterior and non-central placenta are independent risk factors for invasive PAS in patients with placenta previa, during which we should be more cautious in treatment.

"Living in a vacuum": Lived experiences of maternal near-miss among women with placenta accreta spectrum

BACKGROUND

Placenta accreta spectrum (PAS) is one of the life-threatening complications of pregnancy, the prevalence of which has increased in parallel with the caesarean section rate.

OBJECTIVE

The purpose of this study was to investigate the experiences of mothers with PAS who have also experienced maternal near miss.

METHODS

The participants of this study included 8 mothers who had experienced near miss due to placenta accreta during the past year, as well as two husbands and two health care professionals. Data collection was done using face-to-face, in-depth virtual and in-person interviews. In this qualitative study, the interpretive phenomenological analysis approach was used to analyse the data.

RESULTS

The superordinate theme that emerged from the lived experiences of the studied mothers is 'Living in a vacuum', which was derived from 3 main themes. The theme of 'distorted identity' is related to the mothers' experience of losing the uterus as a symbol of femininity and nostalgia for the former self. The theme of 'exacerbated exhaustion' indicates the burnout and fatigue perceived by these mothers and has dimensions far beyond the exhaustion caused by performing parenting duties. The third theme, 'a threatened future', reflects these mothers' vague image of the future in terms of health, preservation of life, and the continuation of living together with the husband.

CONCLUSIONS

It seems that mothers with PAS need to be covered by integrated and well-organised psycho-social support from the time they are diagnosed with the complication until long after delivery due to the high potentiality of maternal near miss.

Trend and risk Factors for Severe Peripartum Maternal morbidity - a population-based Cohort Study

OBJECTIVES

While the rates of maternal mortality in developed countries have remained low in recent years, rates of severe maternal morbidity (SMM) are still increasing in high income countries. As a result, SMM is currently used as a measure of maternity care level. The aim of this study was to investigate the prevalence and risk factors of SMM surrounding childbirth.

METHODS

A nested case-control study was performed between the years 2013-2018. SMM was defined as peripartum hospitalization involving intensive care unit (ICU). A comparison was conducted between parturient with SMM to those without, randomly matched for delivery mode and date of birth in a 1:1 ratio. Multivariable logistic regression models were used to evaluate the independent association between SMM and different maternal and pregnancy characteristics.

RESULTS

During the study period, 96,017 live births took place, of which 144 (1.5 per 1,000 live births-0.15%) involved SMM with ICU admissions. Parturient with SMM were more likely to have a history of 2 or more pregnancy losses (18.2% vs. 8.3%, p = 0.004), deliver preterm (48.9% vs. 8.8%, p < 0.001), and suffer from placenta previa (11.9% vs. 1.5%, p < 0.001), and/or placenta accreta (9.7% vs. 1.5%, p = 0.003). Several significant and independent risk factors for SMM were noted in the multivariable regression models: preterm delivery, history of ≥ 2 pregnancy losses, grand-multiparity, Jewish ethnicity, and abnormal placentation (previa or accreta).

CONCLUSIONS FOR PRACTICE

SMM rates in our cohort were lower than reported in developed countries. An independent association exists between peripartum maternal ICU admissions and several demographic and clinical risk factors, including preterm birth and abnormal placentation.

Placenta Percreta Managed by Ultrasound-Guided Vertical Transfundal Uterine Incision with Hysterectomy: Case Report

Placenta accreta spectrum is an obstetrics complication in which the placenta has abnormally adhered to the decidua and uterine wall. Placenta percreta is the rarest and sternest variant of accreta syndrome. In this study, we present a case of placenta percreta where we have done ultrasound-guided trans fundal vertical uterine incision to deliver a healthy fetus and subsequent cesarean hysterectomy. Antepartum diagnosis, involvement of a multidisciplinary team, appropriate counseling of women and their families, ultrasound guidance for placental margin demarcation, and vertical transfundal uterine incision can be considered for patients with placenta percreta.

Placenta accreta spectrum ultrasound stage and fetal growth

OBJECTIVE

to evaluate fetal growth in pregnancies complicated by placenta accreta spectrum (PAS) and to compare fetal growth between cases stratified by ultrasound stage of PAS.

METHODS

This was a prospective multicenter cohort study of women diagnosed with PAS between January 2018 and December 2021. We grouped participants into cases by ultrasound stage (PAS stage 1-3) and controls (PAS0). Fetal growth centiles at three timepoints with median gestational ages of 21 ± 1 weeks (interquartile range [IQR], 20 ± 1-22 ± 0 weeks), 28 ± 0 weeks (IQR, 27 ± 0-28 ± 5 weeks), and 33 ± 0 weeks (IQR, 32 ± 1-34 ± 0 weeks) and birth weight centiles were compared between cases and controls and between those with PAS stratified by ultrasound stage.

RESULTS

A total of 53 women met inclusion criteria, with a mean age of 37 years (standard deviation, ±4.0 years) and body mass index of 27 kg/m² (standard deviation, ±5.8 kg/m² ). Median (IQR) fetal weight centiles were around the 50th centile at each timepoint, with no difference between groups. The incidence of small for gestational age (birth weight ≤ 10th percentile) and large for gestational age (birth weight ≥ 90th percentile) was 11.3% (n = 6) and 15.1% (n = 8), respectively, with no differences by ultrasound stage. The median birth weight centile was 64 (IQR, 26-85), with no differences between cases and controls or by ultrasound stage.

CONCLUSIONS

In our cohort, a diagnosis of PAS was not associated with fetal growth restriction.

Identification of altered miRNAs and their targets in placenta accreta

Placenta accreta spectrum (PAS) is one of the major causes of maternal morbidity and mortality worldwide with increasing incidence. PAS refers to a group of pathological conditions ranging from the abnormal attachment of the placenta to the uterus wall to its perforation and, in extreme cases, invasion into surrounding organs. Among them, placenta accreta is characterized by a direct adhesion of the villi to the myometrium without invasion and remains the most common diagnosis of PAS. Here, we identify the potential regulatory miRNA and target networks contributing to placenta accreta development. Using small RNA-Seq followed by RT-PCR confirmation, altered miRNA expression, including that of members of placenta-specific miRNA clusters (e.g., C19MC and C14MC), was identified in placenta accreta samples compared to normal placental tissues. In situ hybridization (ISH) revealed expression of altered miRNAs mostly in trophoblast but also in endothelial cells and this profile was similar among all evaluated degrees of PAS. Kyoto encyclopedia of genes and genomes (KEGG) analyses showed enriched pathways dysregulated in PAS associated with cell cycle regulation, inflammation, and invasion. mRNAs of genes associated with cell cycle and inflammation were downregulated in PAS. At the protein level, NF-κB was upregulated while PTEN was downregulated in placenta accreta tissue. The identified miRNAs and their targets are associated with signaling pathways relevant to controlling trophoblast function. Therefore, this study provides miRNA:mRNA associations that could be useful for understanding PAS onset and progression.

Uterine rupture with massive hemoperitoneum due to placenta percreta in a second trimester: A case report

Introduction

Uterine rupture due to placenta percreta is very rare. It often occurs in patients with a history of Cesarean section.

Quick diagnosis, management and intervention improves survival rate and decreases maternal and foetal morbidity.

Observation

Patient, 36 years old, mother of three children delivered by cesarean section, admitted for acute abdominal pain in the context of a poorly monitored pregnancy estimated at 25 weeks of amenorrhea.

Pelvic ultrasound showed a large peritoneal effusion with the presence of an evolving intrauterine pregnancy with cardiac activity present, the placenta was with anterior coverage.

An emergency laparotomy revealed uterine rupture with active hemorrhage localized on the anterior uterine scar with placental protrusion was noted. A cesarean section was quickly performed to save the fetus. The placenta was left in place and a difficult hysterectomy was then undertaken.

Discussion

Uterine rupture in second trimester caused by placental percreta is a rare event that can be life threatening for both mother and fetus.

Placenta percreta should be considered when diagnosing internal bleeding in a patient during the first trimester of pregnancy.

Conclusion

Placenta percreta is a rare but severe obstetric complication that is potentially life threatening for both the mother and fetus.

It is important to maintain a high level of clinical suspicion for this disease in pregnant women with acute abdomen, especially those with specific risk factors.

•

Uterine rupture in second trimester caused by placental percreta is a rare event that can be life threatening for both mother and fetus.

•

The clinical presentation of this complication ranges from mild abdominal pain to hemorrhagic shock.

•

Quick diagnosis, management and intervention improves survival rate and decreases maternal and foetal morbidity.

Obstetric complications and outcomes of singleton pregnancy with previous caesarean section according to maternal age

INTRODUCTION

To delineate obstetric complications and neonatal outcomes by maternal age in singleton pregnancies with previous caesarean section (CS).

METHODS

A retrospective study involved 7715 singleton gestations with previous CS was conducted in a single centre. Statistical methods were used to describe and analyse the incidence of various complications and adverse outcomes classified by maternal ages. After selecting the reference group (30-34 years), multivariate logistic-binomial regression model was used to investigate the outcomes using SPSS.

RESULTS

From 2013 to 2017, the proportion of advanced maternal age (AMA, ≥35 years) women with a history of CS increased yearly, especially in the 35-39 years age group. AMA women accounted for 39.4% of all pregnancies and has a high incidence of in vitro fertilization(IVF), progesterone therapy in early pregnancy, pregnancy-induced hypertension (PIH), gestational diabetes mellitus (GDM), placenta previa, premature rupture of membranes (PROM) and postpartum haemorrhage (PPH). Compared to the 30-34 years group, the risks of PIH, GDM, placenta previa, PROM and PPH increased in AMA pregnancies. Very advanced age (≥40 years) may be associated with placenta accreta while young mothers (20-24 years) have a higher prevalence of premature birth. Vaginal bleeding during pregnancy is a risk factor for maternal complications, maternal and neonatal morbidity.

DISCUSSION

AMA is associated with increased risk of PIH, GDM, placenta previa, PROM and PPH. Vaginal bleeding may be a predictor during pregnancy.

Placenta Accreta Spectrum: Prenatal Diagnosis and Management

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

Ultrasound-based nomogram for postpartum hemorrhage prediction in pernicious placenta previa

Background: Pernicious placenta previa (PPP) is one of the most dangerous complications in pregnancy after cesarean section, with high perinatal mortality. This study aimed to develop a nomogram to predict postpartum hemorrhage in patients with PPP.

Methods: A total of 246 patients with confirmed PPP at Shengjing Hospital of China Medical University from January 2018 to December 2021 were included. Patients were divided into to two cohorts depending on a postpartum blood loss of > 1000 ml (n = 146) or ≤ 1000 ml (n = 100). Lasso regression analysis was performed on the risk factors screened by univariate analysis to screen out the final risk factors affecting postpartum hemorrhage. Based on the final risk factors, a Nomogram prediction model with excellent performance was constructed using Logistic regression. A nomogram was constructed with further screening of the selected risk factors of postpartum hemorrhage in PPP. A second nomogram based only on the total ultrasonic risk score was constructed. Decision curve analysis (DCA) was used to evaluate the clinical efficacy of the nomograms.

Results: Older age, larger gestational age, larger neonatal birth weight, presence of gestational diabetes mellitus, larger amniotic fluid index, absence of gestational bleeding, and higher ultrasonic risk single score were selected to establish a nomogram for postpartum hemorrhage in PPP. The area under the curve of the nomogram constructed by Lasso regression analysis was higher than that of the ultrasonic total score alone (0.887 vs. 0.833). Additionally, DCA indicated better clinical efficacy in the former nomogram than in the later nomogram. Furthermore, internal verification of the nomogram constructed by Lasso regression analysis showed good agreement between predicted and actual values.

Conclusion: A nomogram for postpartum hemorrhage in PPP was developed and validated to assist clinicians in evaluating postpartum hemorrhage. This nomogram was more accurate than using the ultrasonic score alone.

Prospective comparative analysis for application and selection of FIESTA sequence and SSFSE sequence in MRI for prenatal diagnosis of placenta previa accreta

Placenta previa accreta patients were examined using fast-imaging employing steady-state acquisition (FIESTA) and single-shot fast spin echo (SSFSE) sequence. The diagnostic value of the two sequences was compared. FIESTA was better than the SSFSE sequence in displaying outline-boundary (excellent: 82 vs. 26), signal-to-noise ratio (excellent: 75 vs. 54) for placenta and uterus. The direct signs detection rate in FIESTA was higher than SSFSE (implantable: P = .028, adhesive: P = .131, penetrating type: P = .326). The indirect signs detection rate in FIESTA was lower than SSFSE (low-signal density: P = .029, uneven-signal density: P = .328, thicker and more vascular shadow: P = 398). FIESTA combining SSFSE demonstrated higher detecting rates (100% for sensitivity, specificity, and accuracy) for all types than single sequence scanning (FIESTA/SSFSE). In conclusion, FIESTA clearly showed the situation of the placenta and uterus in placenta previa accreta patients, with excellent image quality. A combination of FIESTA and SSFSE can improve the diagnostic value of placenta previa accreta.Important statementWhat is already known on this subject? Placenta previa is the most common cause of vaginal bleeding in the third trimester of pregnancy.What do the results of this study add? FIESTA was better than the SSFSE sequence in displaying images and demonstrated higher detection rates for direct signs and lower detection rate comparing the SSFSE sequence. FIESTA combining SSFSE sequence demonstrated higher detecting rates for implantable, adhesive and penetrating types than single sequence scanning.What are the implications of these findings for clinical practice and/or further research? FIESTA sequence clearly showed the situation of placenta and uterus in placenta previa accreta patients, with excellent image quality. Combination of FIESTA and SSFSE sequences can effectively improve the diagnostic value of placenta previa accreta.

Maternal Smoking and the Risk of Placenta Accreta Spectrum: A Systematic Review and Meta-Analysis

Background

This is the first meta-analysis that assessed the association between maternal smoking and the risk of placenta accreta spectrum (PAS), so this study was aimed at investigating the association between maternal smoking and PAS based on observational studies. PAS is defined as a severe obstetric complication due to the abnormal invasion of the chorionic villi into the myometrium and uterine serosa.

Methods

We searched electronic bibliographic databases including PubMed, Web of Science, Scopus, Science Direct, and Google Scholar until January 2022. The results were reported using a random effect model. The chi-square test and the I² statistic were used to assess heterogeneity. Egger's and Begg's tests were used to examine the probability of publication bias. All statistical analyses were performed at a significance level of 0.05 using Stata software, version 11.

Results

Based on the random effect model, the estimated OR of the risk of PAS associated with smoking was 1.21 (95% CI: 1.02, 1.41; I² = 4.7%). Subgroup analysis was conducted based on study design, and the result showed that the association between smoking and PAS among cohort studies was significant 1.35 (95% CI: 1.15, 1.55; I² = 0.0%).

Conclusion

Our results suggested that maternal smoking is a risk factor for the PAS. There was no heterogeneity among studies that reported an association between smoking and the PAS. The Newcastle-Ottawa Scale (NOS) was used to measure study quality.

Outcomes of pregnancies at high-risk for placenta accreta spectrum following negative diagnostic imaging

OBJECTIVES

To assess the pretest and negative post-test probability for placenta accreta spectrum (PAS) in a group of patients with high-risk clinical factors.

METHODS

We included patients with suspected and/or confirmed PAS at our institution over 8 years. Sonography performed by maternal-fetal medicine specialists, and selected patients underwent MRI. Imaging was considered positive if either sonography or MRI suggested PAS. Histopathology was the gold standard for diagnosis of PAS. We assessed the pretest and negative imaging-test probability, and resources required.

RESULTS

We identified 82 high-risk patients with the following: (1) a history of ≥1 cesarean section and/or intrauterine gynecologic procedure and placenta previa in the index pregnancy; (2) a history of >3 cesarean deliveries and/or gynecologic procedures regardless of placental location; (3) prior PAS disorder, or retained placenta requiring manual extraction and/or curettage, complicated by postpartum hemorrhage; and (4) suspected cesarean section scar pregnancy. Histopathology confirmed PAS in 52 patients, with pretest probability of 63%. Imaging correctly identified 44/50 cases with PAS, and excluded this condition in 24/30 cases. Thus, the positive and negative post-test probability for PAS following negative imaging was 88 and 20%, respectively. Of the six patients with false-negative imaging, all had either surgical complications or required care beyond that for routine cesarean section.

CONCLUSIONS

Although diagnostic imaging is sensitive, the negative posttest probability remains high in women with high pretest probability for PAS. Therefore, women at high risk for PAS should be managed in experienced centers by a multidisciplinary team even if imaging is negative.

Life After Amsterdam: Placental Pathology Consensus Recommendations and Beyond

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

Bleeding-related outcomes of low-risk total placenta previa are equivalent to those of partial/marginal placenta previa

OBJECTIVE

To clarify whether "low-risk total PP" patients bleed more than partial/marginal PP patients.

MATERIALS AND METHODS

The retrospective cohort study was performed involving patients with PP between April 2006 and December 2018. The placental position was determined by ultrasound. From medical charts, the backgrounds as well as obstetric and neonatal outcomes of PP patients were retrieved.

RESULTS

This study included 349 patients with PP, which was classified into three types according to the distance between the placenta and internal ostium: total (n = 174), partial (n = 52), and marginal (n = 123) PP. In total PP patients, three factors (prior CS, anterior placenta, and placental lacunae on ultrasound) significantly increased blood loss at CS, the need for hysterectomy, homologous transfusion (≥10 U), and ICU admission. No significant difference was observed in bleeding-related poor outcomes (rate of blood loss ≥2000 mL, amount of homologous transfusion, need for hysterectomy, and ICU admission) between total PP patients without all three factors: "low-risk total PP patients" and partial/marginal PP patients (19.8 vs. 17.1%; p = 0.604, 3.7 vs. 1.1%; p = 0.330, 1.2 vs. 1.1%; p = 1.000, and 1.2 vs. 1.1%; p = 1.000, respectively).

CONCLUSION

Prior CS, anterior placenta, and placental lacunae on ultrasound were risk factors for a bleeding-related poor outcome in total PP patients. Total PP patients without these three factors showed the same bleeding-related poor outcome as partial/marginal PP patients.

Placenta Accreta has a Low Association with Hypertensive Disease During Pregnancy: A Systematic Review Incorporating a Network Meta-analysis

A meta-analysis was performed to evaluate the potential relationship between hypertensive disease during pregnancy and placenta accreta. A systematic literature search in OVID, Embase, Cochrane Library, PubMed, and Google scholar up to May 2021 was done, and 4 studies were found including 47,353 pregnant women at the start of the study; 4283 of them had hypertensive disease during pregnancy and 493 had placenta accreta. They were reporting relationships between hypertensive disease during pregnancy and placenta accreta. The odds ratio (OR) with 95% confidence intervals (CIs) was calculated to assess the potential relationship between hypertensive disease during pregnancy and placenta accreta using the dichotomous with a random or fixed-effect model. Hypertensive disease during pregnancy was significantly related to lower prevalence of placenta accreta (OR, 0.60; 95% CI, .38-.94, p = 0.03) compared with control (no hypertensive disease during pregnancy). When looking at the result comparing the prevalence of hypertensive disease during pregnancy in women with placenta accreta compared with control (no placenta accreta), we found that the placenta accreta was significantly related to lower prevalence of hypertensive disease during pregnancy (OR, 0.59; 95% CI, 0.38-0.94, p = 0.03) compared with control. Hypertensive disease during pregnancy may have a lower prevalence of placenta accreta. Further studies are required to validate these findings.

Hypertension in pregnancy as a risk factor for placenta accreta spectrum: a systematic review incorporating a network meta-analysis

BACKGROUND

A meta-analysis was performed to evaluate the potential effects of hypertension in pregnancy on the placenta accreta spectrum.

METHODS

A systematic literature search in OVID, Embase, Cochrane Library, PubMed, and Google Scholar up to May 2021 was done, and six studies were found including 126,224 pregnant women; 7164 of them had hypertension in pregnancy and 816 had placenta accreta spectrum. They were reporting relationships between the potential effects of hypertension in pregnancy on the placenta accreta spectrum. The odds ratio (OR) with 95% confidence intervals (CIs) was calculated to assess the potential effects of hypertension in pregnancy on the placenta accreta spectrum using the dichotomous with a random- or fixed-effect model.

RESULTS

Pregnancy-induced hypertension was significantly related to lower prevalence of placenta accreta spectrum (OR 0.56; 95% CI 0.37-0.84, p = 0.005) with no heterogeneity (I² = 0%) compared to control (no hypertension in pregnancy). When looking at the result comparing the prevalence of hypertension in pregnancy in women with placenta accrete compared to control (no placenta accrete), we found that the placenta accreta spectrum was significantly related to lower prevalence of hypertension in pregnancy (OR 0.65; 95% CI 0.43-0.98, p = 0.04) compared to control.

CONCLUSIONS

Hypertension in pregnancy may have a lower prevalence of placenta accrete. Further studies are required to validate these findings.

Pregnancy Patterns Impact Live Birth Rate for Patients With Intrauterine Adhesions After Hysteroscopic Adhesiolysis: A Retrospective Cohort Study

Objective

The pregnancy patterns and other factors of live birth for patients with intrauterine adhesions (IUAs) were identified by analyzing the clinical features of pre-, intra-, and post-hysteroscopic adhesiolysis (HA).

Design

A total of 742 patients with IUAs who wanted to become pregnant underwent HA from January 2017 to May 2018 at the Third Xiangya Hospital of Central South University. The patient follow-up period was 2 years post-HA. A logistic regression was performed to analyze the clinical characteristics associated with a live birth for patients with IUAs. Pre-operative clinical indicators included age, gravidity, parity, abortion, IUA recurrence, menstrual patterns, disease course. Intraoperative clinical features assessed in the last operation were uterine cavity length, IUA appearance, IUA area, number of visible uterine cornua, number of visible tubal ostia, AFS scores. Pregnancy patterns were post-hysteroscopic adhesiolysis features.

Results

Among the 742 IUA patients, 348 (46.9%) had a live birth and 394 (53.1%) did not. A bivariate and binary logistic regression analysis showed that IUA patients’ pregnancy patterns, age, number of visible tubal ostia noted by a second-look hysteroscopy, and American Fertility Society (AFS) scores were significantly related to the live birth rate (P < 0.05).

Conclusions

Pregnancy patterns, age, number of visible tubal ostia, and AFS scores were significantly related to the live birth rate and may be considered potential predictors of the live birth rate in IUA patients. The indications of assisted reproductive technology (ART) might be a better choice for patients with recurrent IUAs.

Cervical tourniquet during cesarean section to reduce bleeding in morbidly adherent placenta: a pilot study

Objective:

To evaluate a modified surgical technique aiming to reduce bleeding and preserve fertility in morbidly adherent placenta by cervical tourniquet in cesarean sections.

Methods:

The cesarean section operations and the cervical ligation approach were performed by a single expert consultant obstetrician. The general demographics and clinical characteristics for all participants were collected and studied.

Results:

Eleven participants were involved. The uterus was preserved in nine patients, whereas two patients had hysterectomy. The mean blood loss was 1688.8 ml for patients whose uterus was preserved. The mean length of stay was 5.5 days.

Conclusion:

Cervical ligation is a simple method that can be applied by junior and experienced obstetricians to preserve the uterus.

Placenta accreta is the abnormal adhesion of placenta into the uterine wall. It carries a significant risk for hysterectomy, intrapartum and postpartum hemorrhage, and maternal morbidity and mortality. As the preservation of fertility and femininity is desired by many women, numerous methods were adapted to avoid hysterectomy in patients with placenta accreta. In this study, we describe and evaluate a novel technique to preserve the uterus by ligating the cervix with a Foley catheter.

Pregnancy complications and risk of uterine rupture among women with singleton pregnancies in China

BACKGROUND

The goal of this study was to investigate whether pregnancy complications are associated with an increased risk of uterine rupture (UR) and how that risk changes with gestational age.

METHODS

We obtained all data from China's National Maternal Near Miss Surveillance System (NMNMSS) between 2012 and 2018. Poisson regression analysis was used to assess the risk of UR with pregnancy complications (preeclampsia, gestational diabetes mellitus, placental abruption, placenta previa and placenta percreta) among 9,454,239 pregnant women. Furthermore, we analysed the risks of UR with pregnancy complications in different gestational age groups.

RESULTS

The risk of UR was increased 2.0-fold (1.2-fold to 2.7-fold) in women with pregnancy complications (except for preeclampsia). These associations also persisted in women without a previous caesarean delivery. Moreover, an increased risk of UR before term birth was observed among women with gestational diabetes mellitus, placental abruption and placenta percreta. The risk of UR was slightly higher in women with gestational diabetes mellitus who had a large for gestational age (LGA) foetus, especially at 32 to 36 weeks gestation.

CONCLUSIONS

The risk of UR is associated with gestational diabetes mellitus, placental abruption, placenta previa and placenta percreta, but varies in different gestational ages.

Maternal education and racial/ethnic disparities in nulliparous, term, singleton, vertex cesarean deliveries in the United States

BACKGROUND

Racial and ethnic disparities in obstetrical and neonatal outcomes are prevalent in the United States. Such racial or ethnic disparities have also been documented in the prevalence of cesarean deliveries.

OBJECTIVE

We aimed to evaluate the impact of maternal education on racial or ethnic disparities in the prevalence of low-risk nulliparous, term, singleton, vertex cesarean deliveries in the United States.

STUDY DESIGN

This is a retrospective analysis of the Centers for Disease Control and Prevention live births database (2016–2019). Nulliparous, term, singleton, vertex births from the following racial/ethnic groups were included: non-Hispanic White, non-Hispanic Black, non-Hispanic Asian, and Hispanic. Pregnancies complicated by gestational or pregestational diabetes mellitus and hypertensive disorders were excluded. Data were analyzed on the basis of the level of maternal education (less than high school graduate, high school graduate, college graduate, and advanced degree). We compared the prevalence of cesarean deliveries among the different racial or ethnic groups within each education level using Pearson chi-square test with Bonferroni adjustment. Multivariate logistic regression was performed to assess the association between cesarean deliveries and maternal race/ethnicity, maternal education, and the interaction between maternal race or ethnicity and education level, while controlling for potential confounders. To demonstrate the effect of the interaction, separate logistic regression models with similar covariates were performed for each education level and for each race/ethnicity group. Statistical significance was determined as P<.05, and results were displayed as adjusted odds ratios with 95% confidence intervals.

RESULTS

The overall prevalence of cesarean deliveries during the study period was 23.4% (695,214 of 2,969,207 births). All racial or ethnic minority groups had higher rates of cesarean deliveries than non-Hispanic White women (non-Hispanic Black, 27.4%; non-Hispanic Asian, 25.6%; Hispanic, 23.0%; and non-Hispanic White, 22.4%; [P<.001 for all comparisons]). Similar racial or ethnic differences in cesarean delivery rates were detected among all education levels. Higher levels of education were associated with a lower likelihood of cesarean delivery (adjusted odds ratio, 0.88; [95% confidence interval, 0.87–0.89]) in women with advanced degrees than in women who did not graduate from high school. However, although maternal education was associated with a protective effect in non-Hispanic White and non-Hispanic Asian women (adjusted odds ratio, 0.83 [95% confidence interval, 0.81–0.85] and adjusted odds ratio, 0.81 [95% confidence interval, 0.77–0.86], respectively, for women with advanced degrees), it had a smaller protective effect in non-Hispanic Black women (adjusted odds ratio, 0.93 [95% confidence interval, 0.89–0.97]) and no protective effect in Hispanic women (adjusted odds ratio, 0.98 [95% confidence interval, 0.96–1.01]).

CONCLUSION

We document a significant racial/ethnic disparity in the prevalence of low-risk nulliparous, term, singleton, vertex cesarean deliveries in the United States. Furthermore, our findings suggest that although a higher level of maternal education is associated with a lower likelihood of cesarean delivery, this protective effect varies among racial or ethnic groups. Further research is needed to investigate the underlying causes for this racial/ethnic disparity.

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

ABSTRACT

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

Mode of birth in women with low-lying placenta: protocol for a prospective multicentre 1:3 matched case-control study in Italy (the MODEL-PLACENTA study)

INTRODUCTION

The term placenta praevia defines a placenta that lies over the internal os, whereas the term low-lying placenta identifies a placenta that is partially implanted in the lower uterine segment with the inferior placental edge located at 1-20 mm from the internal cervical os (internal-os-distance). The most appropriate mode of birth in women with low-lying placenta is still controversial, with the majority of them undergoing caesarean section. The current project aims to evaluate the rate of vaginal birth and caesarean section in labour due to bleeding by offering a trial of labour to all women with an internal-os-distance >5 mm as assessed by transvaginal sonography in the late third trimester.

METHODS AND ANALYSIS

The MODEL-PLACENTA is a prospective, multicentre, 1:3 matched case-control study involving 17 Maternity Units across Lombardy and Emilia-Romagna regions, Italy. The study includes women with a placenta located in the lower uterine segment at the second trimester scan. Women with a normally located placenta will be enrolled as controls. A sample size of 30 women with an internal-os-distance >5 mm at the late third trimester scan is needed at each participating Unit. Since the incidence of low-lying placenta decreases from 2% in the second trimester to 0.4% at the end of pregnancy, 150 women should be recruited at each centre at the second trimester scan. A vaginal birth rate ≥60% in women with an internal-os-distance >5 mm will be considered appropriate to start routinely admitting to labour these women.

ETHICS AND DISSEMINATION

Ethical approval for the study was given by the Brianza Ethics Committee (No 3157, 2019). Written informed consent will be obtained from study participants. Results will be disseminated by publication in peer-reviewed journals and presentation in international conferences.

TRIAL REGISTRATION NUMBER

NCT04827433 (pre-results stage).

The potential risk factors of placenta increta and the role of octamethylcyclotetrasiloxane

BACKGROUND

The study aimed to investigate the potential risk factors for the placenta accreta spectrum (PAS), determine the predictive value of a diagnostic model, and evaluate the effects of octamethylcyclotetrasiloxane (OMCTS) on trophoblast proliferation and migration.

METHODS

This case-control study included 244 pregnant women with PAS and 327 normal pregnant women who visited Guangzhou Women and Children's Medical Centre, China, from January 2014 to December 2017. Blood was collected from 42 women with PAS and 77 controls, and plasma specimens were analyzed by gas chromatography-time-of-flight mass spectrometry. In addition, the proliferation and migration of trophoblast cells were examined after treatment with OMCTS.

RESULTS

We found an association between the risk of PAS and clinical factors related to fasting blood glucose levels (BS0, OR = 5.78), as well as factors related to endometrial injury [history of cesarean section (OR = 179.59), uterine scarring (OR = 68.37), and history of abortion (OR = 5.66)]. Equally important, pregnant women with PAS had significantly higher plasma OMCTS concentrations than controls. In vitro, we found that OMCTS could promote the proliferation and migration of HTR8/SVneo cells. The model of combining clinical factors and OMCTS had a good performance in PAS prediction (AUC = 0.97, 95% CI 0.78-0.93).

CONCLUSIONS

The early diagnosis of PAS in pregnant women requires assessing risk factors, metabolic status, and BS0 levels before 20 weeks of gestation. OMCTS may be related to the development of PAS by promoting trophoblast cell proliferation and migration.

Placenta Accreta Spectrum

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

Comparison of Ultrasound Descriptors of Abnormally Invasive Placenta (AIP) over the Course of the Second and Third Trimester-Is an Increase Verifiable?

Limited data exist regarding the course of abnormally invasive placentation (AIP) (=placenta accreta spectrum (PAS)) during the 2nd and 3rd trimester, although this knowledge would be important for optimal patient care. In this retrospective single-center longitudinal cohort study, potential aggravation of AIP was evaluated in 37 patients with ultrasound (US) pictures stored on a minimum of two visits. Five raters, blinded to diagnosis and gestational age, judged the degree of AIP as recommended by the International Society for PAS. The probability of invasiveness was estimated as absent, low, intermediate, severe (0–3 points), the extent as absent, focal, diffuse (0–2 points), and the presence and appearance of each US-sign as absent, mild, severe (0–3 points). None of the 10 judged signs appeared more severe (p ≥ 0.41) with progressing pregnancy. Neither the number of positively scored US-signs (earlier scan; 6.14 ± 2.06, later scan; 5.94 ± 2.16; p = 0.28), nor the estimated probability & extent of AIP rose (3.69 ± 1.15 vs. 3.67 ± 1.22; p = 1.0). Test-retest reliability corroborated excellent agreement between visits (mean number of positive US-signs ICC (3,1) = 0.94, 95% CI 0.91–0.97; p < 0.0001). Overall, there was no clinically detectable increase in invasiveness over the course of the 2nd and 3rd trimester. This should be further evaluated in prospective studies.

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

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

What is new in peripartum hysterectomy? A seventeen year experience in a tertiary hospital

OBJECTIVE

To identify changing trends in peripartum hysterectomy (PH), both elective. cesarean hysterectomy and emergency cesarean hysterectomy, at a single training and research hospital over the last 17 years in Istanbul, Turkey.

MATERIALS AND METHODS

A retrospective cohort study was performed between January 2001 and September 2017. The records of all patients who had PH at Kanuni Sultan Süleyman Training and Research Hospital were analyzed.

RESULTS

There were 243 cases of PH during the study period. A total of 266,386 births occurred, of which 60.1% were vaginal deliveries and 39.8% were cesarean sections. The incidence of PH increased from 0.67 per 1000 deliveries to 1.14 per 1000 deliveries during 2001-2008 and 2009-2017, respectively, with an overall incidence of 0.91 per 1000 deliveries during the 17 years. The main indication for PH changed significantly during this time from uterine atony (57.1%) to placenta accreta spectrum (85%). About 37% of women who underwent PH had at least one previous cesarean delivery during 2001-2008, whereas that percentage increased to 95.4% during 2009-2017.

CONCLUSION

Placenta accreta spectrum was the leading cause of PH and was associated with significant maternal morbidity and mortality.

A systematic review and meta-analysis of obstetric and maternal outcomes after prior uterine artery embolization

This study aimed to review the obstetric complications during subsequent pregnancies after uterine artery embolization (UAE) for postpartum hemorrhage (PPH) by exploring the relationship between prior UAE and obstetric complications through a meta-analysis. We conducted a systematic literature review through March 31, 2021, using PubMed, Scopus, and the Cochrane Central Register of Controlled Trials in compliance with the PRISMA guidelines and determined the effect of prior UAE for PPH on the rate of placenta accreta spectrum (PAS), PPH, placenta previa, hysterectomy, fetal growth restriction (FGR), and preterm birth (PTB). Twenty-three retrospective studies (2003–2021) met the inclusion criteria. They included 483 pregnancies with prior UAE and 320,703 pregnancies without prior UAE. The cumulative results of all women with prior UAE indicated that the rates of obstetric complications PAS, hysterectomy, and PPH were 16.3% (34/208), 6.5% (28/432), and 24.0% (115/480), respectively. According to the patient background-matched analysis based on the presence of prior PPH, women with prior UAE were associated with higher rates of PAS (odds ratio [OR] 20.82; 95% confidence interval [CI] 3.27–132.41) and PPH (OR 5.32, 95% CI 1.40–20.16) but not with higher rates of hysterectomy (OR 8.93, 95% CI 0.43–187.06), placenta previa (OR 2.31, 95% CI 0.35–15.22), FGR (OR 7.22, 95% CI 0.28–188.69), or PTB (OR 3.00, 95% CI 0.74–12.14), compared with those who did not undergo prior UAE. Prior UAE for PPH may be a significant risk factor for PAS and PPH during subsequent pregnancies. Therefore, at the time of delivery, clinicians should be more attentive to PAS and PPH when women have undergone prior UAE. Since the number of women included in the patient background-matched study was limited, further investigations are warranted to confirm the results of this study.

Deep learning and radiomics analysis for prediction of placenta invasion based on T2WI

The purpose of this study was to explore whether the Nomogram, which was constructed by combining the Deep learning and Radiomic features of T2-weighted MR images with Clinical factors (NDRC), could accurately predict placenta invasion. This retrospective study included 72 pregnant women with pathologically confirmed placenta invasion and 40 pregnant women with normal placenta. After 24 gestational weeks, all participants underwent magnetic resonance imaging. The uterus and placenta regions were segmented in magnetic resonance images on sagittal T2WI. Ninety-three radiomics features were extracted from the placenta region, and 128 deep features were extracted from the uterus region using a deep neural network. The least absolute shrinkage and selection operator (LASSO) algorithm was used to filter these 221 features and to form the combined signature. Then the combined signature (CS) and clinical factors were combined to construct a nomogram. The accuracy, sensitivity, specificity and AUC of the nomogram were compared with four machine learning methods. The model NDRC was trained on the dataset of 78 pregnant women in the training cohort. Finally, the model NDRC was compared with four machine learning methods on the independent validation cohort of 34 pregnant women. The results showed that the prediction accuracy, sensitivity, specificity and AUC of the NDRC model were 0.941, 0.952, 0.923 and 0.985 respectively, which outperforms the traditional machine learning methods which rely on radiomics features and deep learning features alone.

Diffusion MRI Based Myometrium Tractography for Detection of Placenta Accreta Spectrum Disorder

BACKGROUND

Prenatal diagnosis of placenta accreta spectrum (PAS) disorders is difficult. Magnetic resonance imaging (MRI) has been shown to be a useful supplementary method to ultrasound.

PURPOSE

To investigate diffusion MRI (dMRI) based tractography as a tool for detecting PAS disorders, and to evaluate its performance compared with anatomical MRI.

STUDY TYPE

Prospective.

POPULATION

Forty-seven pregnant women in the third trimester with risk factors for PAS.

FIELD STRENGTH/SEQUENCE

Using fast imaging employing steady-state acquisition and high-angular resolution dMRI at 1.5 Tesla.

ASSESSMENT

Diagnosis of PAS was performed by three radiologists based on the dMRI-based feature of myometrial fiber discontinuity and on commonly used anatomical features including presence of dark band, discontinuous myometrium and bladder wall interruption. We evaluated the sensitivity, specificity, accuracy, and area-under-the-curve (AUC) of the individual features and established an integrated model with random forest analysis.

STATISTICAL TESTS

Maternal age and gestational age at scan were compared between PAS and control group using a t-test, and childbearing history was compared using a chi-squared test. The random forest model was employed to combine the anatomical and dMRI features with 5-fold cross-validation, and the weight of each feature was normalized to evaluate its importance in predicting PAS.

RESULTS

Based on surgical pathology reports, 16 out of 47 patients had confirmed PAS. The anatomical feature of dark bands and tractography marker achieved the highest AUC of 0.842 for predicting PAS, and the integrated anatomical and tractography features further improved the AUC of 0.880 with an accuracy of 87.2%. The tractography feature contributed most (30.1%) to the integrated model.

DATA CONCLUSION

Myometrial tractography demonstrated superior performance in detecting PAS. Moreover, the combination of dMRI-based tractography and anatomical MRI could potentially improve the diagnosis of PAS disorders in clinical practice.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY STAGE: 2.

Quantifying magnetic resonance imaging features to classify placenta accreta spectrum (PAS) in high-risk gravid patients

OBJECTIVE

This study aimed to quantify the magnetic resonance imaging (MRI) features of placenta accreta spectrum (PAS) and to use MRI-based scores to classify them in high-risk gravid patients.

MATERIALS AND METHODS

The clinical data and MRI features of 65 high-risk gravid patients diagnosed with PAS were retrospectively reviewed. The MRI features of PAS were analysed and compared using the chi-squared test, and the odds ratios (ORs) for significant risk factors for classification of PAS were identified via a multivariate logistic regression model. A receiver-operating characteristic (ROC) curve was used to calculate cut-off values and their corresponding sensitivity, specificity, and accuracy in classifying PAS.

RESULTS

We identified 3 significant risk features for classification of PAS, including placental heterogeneity (OR = 13.604), abnormal vascularization at the placental-maternal interface (OR = 9.528), and focal myometrial interruption (OR = 118.779). The significant risk features for classification of PAS were scored according to their OR values, as 3 points (OR ≥ 20), 2 points (10 ≤ OR < 20), or 1 point (OR < 10). Based on the scores of the 3 risk features, a cut-off score of 4.5 points achieved optimal sensitivity (94.3%), specificity (90%), and accuracy (92.3%) for classifying PAS in high-risk gravid patients.

CONCLUSION

Quantifying these MRI features including placental heterogeneity, abnormal vascularization at the placental-maternal interface, and focal myometrial interruption can make a classification of PAS in high-risk gravid patients.

Antenatal diagnosis of placenta accreta spectrum after in vitro fertilization-embryo transfer: a systematic review and meta-analysis

Increasing evidence suggests a relationship between in vitro fertilization-embryo transfer (IVF-ET) and placenta accreta spectrum (PAS). Some studies have reported a lower rate of antenatal diagnosis of PAS after IVF-ET compared to PAS with spontaneous conception. This study aimed to review the diagnostic accuracy of PAS after IVF-ET and to explore the relationship between IVF-ET pregnancy and PAS. According to the PRISMA guidelines, a comprehensive systematic review of the literature was conducted through August 31, 2020 to determine the effects of IVF-ET on PAS. In addition, a meta-analysis was conducted to explore the relationship between IVF-ET pregnancy and PAS. Twelve original studies (2011–2020) met the inclusion criteria. Among these, 190,139 IVF-ET pregnancies and 248,534 spontaneous conceptions met the inclusion criteria. In the comparator analysis between PAS after IVF-ET and PAS with spontaneous conception (n = 2), the antenatal diagnosis of PAS after IVF-ET was significantly lower than that of PAS with spontaneous conception (22.2% versus 94.7%, P < 0.01; < 12.9% versus 46.9%, P < 0.01). The risk of PAS was significantly higher in women who conceived with IVF-ET than in those with spontaneous conception (odds ratio [OR]: 5.03, 95% confidence interval [CI]: 3.34–7.56, P < 0.01). In the sensitivity analysis accounting for the type of IVF-ET, frozen ET was associated with an increased risk of PAS (OR: 4.60, 95%CI: 3.42–6.18, P < 0.01) compared to fresh ET. Notably, frozen ET with hormone replacement cycle was significantly associated with the prevalence of PAS compared to frozen ET with normal ovulatory cycle (OR: 5.76, 95%CI 3.12–10.64, P < 0.01). IVF-ET is associated with PAS, and PAS after IVF-ET was associated with a lower rate of antenatal diagnosis. Therefore, clinicians can pay more attention to the presence of PAS during antenatal evaluation in women with IVF-ET, especially in frozen ET with hormone replacement cycle.

The relation between maternal obesity and placenta accreta spectrum: A multinational database study

INTRODUCTION

It has been suggested that women with obesity have increased risk of developing placenta accreta spectrum (PAS). It is unclear if this is independent of the increased risk of cesarean delivery seen with obesity itself. The aim of this study was to explore the association between maternal obesity and PAS, particularly severe PAS (percreta).

MATERIAL AND METHODS

This is a cohort study based on cases recorded in the International Society for Placenta Accreta Spectrum (IS-PAS) database between April 2008 and May 2019. Multivariable logistic regression was used to explore the effect of maternal obesity on severity of PAS; this model was adjusted for other known risk factors including previous cesarean deliveries, maternal age, and placenta previa. The estimated rate of obesity in a hypothetical cohort with similar characteristics (previous cesarean delivery and same parity) was calculated and compared with the observed rate of obesity in the women of the PAS cohort (one sample test of proportions).

RESULTS

Of the 386 included women with PAS, 227 (58.8%) had severe disease (percreta). In univariable analysis, maternal obesity initially appeared to be associated with increased odds of developing the most severe type of PAS, percreta (odds ratio [OR] 1.87; 95% CI 1.14-3.09); however, this association was lost after adjustment for other risk factors including previous cesarean delivery (OR 1.44; 95% CI 0.85-2.44). There was no difference in the observed rate of obesity and the rate estimated based on the risk of cesarean delivery from obesity alone (31.3% vs 36.8%, respectively; P = .07).

CONCLUSIONS

Obesity does not seem to be an independent risk factor for PAS or severity for PAS. These findings are relevant for clinicians to provide accurate counseling to women with obesity regarding increased risks related to pregnancy.