Incidence and Clinical Implications of Placenta Accreta Spectrum after Treatment for Asherman Syndrome

Asherman syndrome at single-cell resolution

This comprehensive review aimed to provide insights into the Asherman syndrome's historical background, clinical manifestations, classifications, obstetrical challenges, and current treatment approaches. The syndrome is characterized by intrauterine adhesions and fibrotic changes within the uterine tract as well as symptoms including menstrual irregularities, pelvic pain and infertility. The primary causes of Asherman syndrome are often associated with iatrogenic complications and congenital uterine defects. The syndrome results in certain obstetrical challenges, including recurrent pregnancy loss, placenta abnormalities, preterm birth, and intrauterine growth retardation, emphasizing the need for effective management. Hysteroscopic adhesiolysis represents the current gold standard treatment, but challenges persist because of adhesion recurrence and obstetrical complications. In this sense, emerging therapies were explored, including paracrine-acting factors, tissue-engineered scaffolds, and cell-based therapies. Autologous CD133+ bone marrow-derived stem cell therapy shows promise, with clinical trials demonstrating improved endometrial conditions and positive obstetrical outcomes. The review concludes by highlighting the potential of single-cell RNA sequencing to unravel the molecular mechanisms behind Asherman syndrome. This advanced technology offers insights into the gene expression profiles of individual cells, fostering a deeper understanding of Asherman syndrome pathogenesis and the development of innovative therapeutic strategies.

Spontaneous Uterine Rupture in Pregnancy After Treatment of Asherman Syndrome

STUDY OBJECTIVE

Women with Asherman syndrome are at high risk of recurrent adhesions and pregnancy complications. Spontaneous uterine rupture is a rare but life-threatening complication, associated with severe maternal and fetal morbidity and mortality. Uterine ruptures can occur after extended induction of labor or a history of cesarean section, whereas spontaneous uterine rupture in an unscarred uterus is rare. Aim of this study is to evaluate the incidence of spontaneous uterine rupture among women with Asherman syndrome treated by hysteroscopy and without a history of cesarean section.

DESIGN

Prospective cohort study.

SETTING

Asherman Expertise Center of the Spaarne Gasthuis, The Netherlands.

PATIENTS

Women were defined by as patients with Asherman syndrome when they had one or more clinical features and the presence of hysteroscopically confirmed intrauterine adhesions.

INTERVENTIONS

Hysteroscopic adhesiolysis and a second-look hysteroscopy two months after the initial procedure.

MEASUREMENTS AND RESULTS

Data on the severity of adhesions and ongoing pregnancy after treatment were collected prospectively. A total of 428 women with Asherman syndrome were included, 4 women (0.9%) experienced spontaneous uterine rupture. The timing varied, none of the affected women were in active labor and the occurrence of uterine rupture was not related to the severity of adhesions. Ruptures were all found in the fundus. One woman had a history of perforation of the uterine wall located in the fundus. Neonatal outcomes were poor, two cases had intrauterine neonatal death and two cases had long-term lifelong disability. One woman had a second uterine rupture.

CONCLUSION

Women with Asherman syndrome are at risk of uterine rupture, a pregnancy complication with significant consequences that is challenging to predict and may also be associated with history of uterine perforation. Clinicians should be aware of this risk in women treated with hysteroscopic adhesiolysis and consider counseling these patients accordingly prior to treatment.

Risk of Placenta Accreta Spectrum Disorder After Prior Non-Cesarean Delivery Uterine Surgery: A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate the association between previous non-cesarean uterine surgery and placenta accreta spectrum (PAS) in subsequent pregnancies.

DATA SOURCES

PubMed, EMBASE, the Cochrane Library, ClinicalTrials.gov, CNKI (China National Knowledge Infrastructure), and Wan-fang Database were searched from inception to April 2024, supplemented by manual searches.

METHODS OF STUDY SELECTION

Studies included prospective, retrospective cohort, case-control, and cross-sectional studies involving pregnant women diagnosed with PAS and reporting at least one risk factor associated with previous uterine surgery.

TABULATION, INTEGRATION, AND RESULTS

Two authors independently screened potentially eligible studies and extracted data. The quality of the studies was assessed with the Newcastle-Ottawa Scale. The pooled odds ratios (ORs), adjusted ORs, and their 95% CIs were estimated with fixed- or random-effects models if the heterogeneity (I2) was high. Sensitivity analyses were conducted to account for potential study bias. The main measures were myomectomy, uterine artery embolization, dilatation and curettage, hysteroscopic adhesiolysis, abortion, endometrial ablation, and operative hysteroscopy. A total of 38 studies involving 7,353,177 participants were included in the systematic review, with an overall prevalence of PAS of 0.16%, and 31 studies were included in the meta-analysis. Prior non-cesarean uterine surgeries were associated with PAS in subsequent pregnancy (pooled OR 2.29, 95% CI, 1.43-3.68). Distinct associations between specific uterine surgery and PAS included myomectomy (OR 2.29, 95% CI, 1.77-2.97), uterine artery embolization (OR 43.16, 95% CI, 20.50-90.88), dilatation and curettage (OR 2.28, 95% CI, 1.78-2.93), hysteroscopic adhesiolysis (OR 7.72, 95% CI, 4.10-14.53), abortion (OR 1.65, 95% CI, 1.43-1.92), endometrial ablation (OR 20.26, 95% CI, 17.15-23.93), and operative hysteroscopy (OR 3.10, 95% CI, 1.86-5.18).

CONCLUSION

Prior non-cesarean uterine surgery is associated with a significantly increased odds for development of PAS in subsequent pregnancy, and the risk varies depending on the types of uterine surgery.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO: CRD42024552210.

Hysteroscopic Endometrial Defect Following Adenomyomectomy and Incidence of Placenta Accreta Spectrum and Uterine Rupture Complications for Subsequent Pregnancy

Adenomyomectomy, a therapeutic option for women with adenomyosis who wish to preserve their fertility, has been reported to pose a risk of developing placenta accreta spectrum (PAS) and uterine rupture in future pregnancies. However, the specific clinical factors contributing to these occurrences remain elusive. This study aimed to explore the association between hysteroscopic findings after adenomyomectomy and the incidence of PAS in subsequent pregnancies. We conducted a retrospective analysis of 10 patients (11 pregnancies) who had undergone hysteroscopy following adenomyomectomy and had later delivered at our hospital. In 6/10 patients, postoperative hysteroscopy revealed endometrial defects. However, subsequent evaluations confirmed endometrial restoration within 7-21 months, with five patients achieving pregnancy afterward. The only other patient conceived naturally without waiting for endometrial restoration, resulting in uterine rupture from the site of the placenta percreta. The incidence of clinically diagnosed PAS during cesarean section was 100% (1/1) in pregnancies with preconceptional endometrial defects, 20% (1/5) in those with endometrial restoration, and 0% (0/5) in pregnancies without endometrial defects. Similarly, the incidence of pathologically diagnosed PAS was 100% (1/1), 60% (3/5), and 20% (1/5) in these groups, respectively. Thus, endometrial defects were frequently detected after adenomyomectomy and recovered over time, whereas one patient without endometrial restoration developed uterine rupture complicated by PAS. This study demonstrates that while the presence of an endometrial defect identified by postoperative hysteroscopy may be a risk factor for the occurrence of PAS in subsequent pregnancies, allowing sufficient recovery time for the endometrium may help reduce the risk of uterine rupture.

Construction of deep learning-based convolutional neural network model for automatic detection of fluid hysteroscopic endometrial micropolyps in infertile women with chronic endometritis

OBJECTIVE(S)

Chronic endometritis (CE) is a localized mucosal inflammatory disorder associated with female infertility of unknown etiology, endometriosis, tubal factors, repeated implantation failure, and recurrent pregnancy loss, along with atypical uterine bleeding and iron deficiency anemia. Diagnosis of CE has traditionally relied on endometrial biopsy and detection of CD138(+) endometrial stromal plasmacytes. To develop a less invasive diagnostic system for CE, we aimed to construct a deep learning-based convolutional neural network (CNN) model for the automatic detection of endometrial micropolyps (EMiP), a fluid hysteroscopy (F-HSC) finding recognized as tiny protrusive lesions that are closely related to this disease.

STUDY DESIGN

This is an in silico study using archival images of F-HSC performed at an infertility center in a private clinic. A total of 244 infertile women undergoing F-HSC on the days 6-12 of the menstrual cycle between April 2019 and December 2021 with histopathologically-confirmed CE with the aid of immunohistochemistry for CD138 were utilized.

RESULTS

The archival F-HSC images of 208 women (78 with EMiP and 130 without EMiP) who met the inclusion criteria were finally subjected to analysis. Following preprocessing of the images, half a set was input into a CNN architecture for training, whereas the remaining images were utilized as the test set to evaluate the performance of the model, which was compared with that of the experienced gynecologists. The sensitivity, specificity, accuracy, precision, and F1-score of the CNN model-aided diagnosis were 93.6 %, 92.3 %, 92.8 %, 88.0 %, and 0.907, respectively. The area under the receiver operating characteristic curves of the CNN model-aided diagnosis (0.930) was at a similar level (p > .05) to the value of conventional diagnosis by three experienced gynecologists (0.927, 0.948, and 0.906).

CONCLUSION

These findings indicate that our deep learning-based CNN is capable of recognizing EMiP in F-HSC images and holds promise for further development of the computer-aided diagnostic system for CE.

Incidence, risk factors and maternal outcomes of unsuspected placenta accreta spectrum disorders: a retrospective cohort study

BACKGROUND

To identify incidence and underlying risk factors for unsuspected placenta accreta spectrum (PAS) and compare the maternal outcomes between suspected and unsuspected cases in three large academic referral centers.

METHODS

A retrospective cohort study was conducted in three university-based tertiary referral centers from Jan 1st, 2013, to Dec 31st, 2022. All cases of PAS confirmed by pathology were included in the study. Unsuspected PAS cases were diagnosed at the time of delivery, while suspected cases served as the control group. Potential risk factors were compared between the two groups. Multivariable regression model was also performed to identify risk factors. Maternal outcomes were also evaluated.

RESULTS

A total of 339 pathology-confirmed PAS cases were included in the study out of 415,470 deliveries, of which 35.4% (n = 120) were unsuspected cases. Unsuspected PAS cases were 7.9 times more likely to have a history of intrauterine adhesions (adjusted odds ratio [aOR] 7.93; 95% confidence interval [CI] 2.35-26.81), 7.0 times more likely to have a history of clinically confirmed PAS (aOR, 6.99; 95% CI 2.85-17.18), 6.3 times more likely to have a posterior placenta (aOR, 6.30; 95% CI 3.48-11.40), and 3.4 times more likely to have a history of placenta previa (aOR, 3.41; 95% CI 1.18-9.82). On the other hand, cases with gravidity > 3, placenta previa, and/or a history of previous cesarean delivery were more likely to be diagnosed antenatally (aOR 0.40, 0.19, 0.36; 95% CI 0.22-0.74, 0.09-0.40, 0.19-0.70). Although the suspected PAS group had a higher proportion of invasive cases and abdominal and pelvic organ injuries (74.4% vs. 25.8%, p < 0.001; 6.8% vs. 1.7%, p = 0.037), the maternal outcomes were more favorable in the sPAS group, with a lower median volume of 24-hour blood loss and blood product transfusion (estimated blood loss in 24 h, 1000 [800-2000] vs. 2000 [1400-2400], p < 0.001; RBC unit transfusion, 0 [0-800] vs. 800 [600-1000], p < 0.001; fresh-frozen plasma transfusion, 0 [0-450] vs. 600 [400-800], p < 0.001).

CONCLUSIONS

Our findings indicate that 35% of patients with PAS were unsuspected prior to delivery. Factors associated with PAS being unsuspected prior to delivery include a history of intrauterine adhesions, a history of clinically confirmed PAS, a posterior placenta, and a history of placenta previa. Additionally, gravidity > 3, a history of previous cesarean delivery, and placenta previa increase the likelihood of antenatal diagnosis.

A cost-effectiveness analysis of intrauterine spacers used to prevent the formation of intrauterine adhesions following endometrial cavity surgery

AIM

To assess, from a United States (US) payer's perspective, the cost-effectiveness of gels designed to separate the endometrial surfaces (intrauterine spacers) placed following intrauterine surgery.

MATERIALS AND METHODS

A decision tree model was developed to estimate the cost-effectiveness of intrauterine spacers used to facilitate endometrial repair and prevent the formation (primary prevention) and reformation (secondary prevention) of intrauterine adhesions (IUAs) and associated pregnancy- and birth-related adverse outcomes. Event rates and costs were extrapolated from data available in the existing literature. Sensitivity analyses were conducted to corroborate the base case results.

RESULTS

In this model, using intrauterine spacers for adhesion prevention led to net cost savings for US payers of $2,905 per patient over a 3.5-year time horizon. These savings were driven by the direct benefit of preventing procedures associated with IUA formation ($2,162 net savings) and the indirect benefit of preventing pregnancy-related complications often associated with IUA formation ($3,002). These factors offset the incremental cost of intrauterine spacer use of $1,539 based on an assumed price of $1,800 and the related increase in normal deliveries of $931. Model outcomes were sensitive to the probability of preterm and normal deliveries. Budget impact analyses show overall cost savings of $19.96 per initial member within a US healthcare plan, translating to $20 million over a 5-year time horizon for a one-million-member plan.

LIMITATIONS

There are no available data on the effects of intrauterine spacers or IUAs on patients' quality of life. Resultingly, the model could not evaluate patients' utility related to treatment with or without intrauterine spacers and instead focused on costs and events avoided.

CONCLUSION

This analysis robustly demonstrated that intrauterine spacers would be cost-saving to healthcare payers, including both per-patient and per-plan member, through a reduction in IUAs and improvements to patients' pregnancy-related outcomes.