Analysis of risk factors for cesarean scar diverticulum: A STROBE-compliant case-control study

Investigating the risk factors for isthmocele development after cesarean delivery

BACKGROUND

Cesarean delivery rates are increasing globally, raising concerns about associated complications such as isthmocele. Isthmoceles are pouch-like defects in the anterior uterine wall at the site of a prior cesarean delivery scar.

OBJECTIVE

This study aimed to determine isthmocele prevalence, associated symptoms, and risk factors among women with a history of cesarean delivery.

STUDY DESIGN

This cross-sectional study evaluated 297 women with prior cesarean delivery using transvaginal ultrasound to screen for isthmocele. Data on demographics, pregnancy details, comorbidities, and indications for cesarean delivery were collected. Isthmocele was defined sonographically as any niche or defect at the hysterotomy site. Descriptive and comparative analyses identified factors associated with isthmocele.

RESULTS

Isthmocele prevalence was 65.3% (n=194). Abnormal vaginal bleeding was reported in 21.1% of participants, pelvic pain by 4.1% of participants, and both by 4.1% of participants. Compared to women without isthmocele, those with isthmocele were older (35.9 vs 31.6 years), had higher body mass index (26.8 vs 25.5 kg/m2), gravidity (1.8 vs 1.3), and parity (1.7 vs 1.2). Repeat cesarean delivery was more common (30.4% vs 12.6%) and elective cesarean delivery less common (33.5% vs 67.9%) among those with isthmocele.

CONCLUSION

Over half of the women with history of cesarean delivery had an isthmocele. Abnormal bleeding was common. Advanced maternal age, obesity, repeat procedures, and certain comorbidities appear to increase risk. Further research on prevention and treatment is warranted given the high prevalence.

A Prediction Model for the Efficacy of Transvaginal Repair in Patients With Cesarean Scar Defect: An Evidence-Based Proposal for Patient Selection

STUDY OBJECTIVE

To establish a prediction model to help doctors determine which patients with cesarean scar defect are more suitable for transvaginal repair.

DESIGN

Retrospective analysis.

SETTING

Xinhua Hospital and Shanghai First Maternity & Infant Hospital between June 2014 and May 2021.

PATIENTS

1015 women who underwent transvaginal repair of cesarean scar defect (CSD).

INTERVENTIONS

All enrolled patients underwent CSD repair performed by the same gynecologist and his team. And followed up a clinic visit at 6 months to record their menstruation and measure multiple parameters of the CSD by Magnetic Resonance Imaging.

MAIN OUTCOMES AND MEASURES

CSD patients are categorized as optimal healing group when the menstruation duration is no more than 7 days, meanwhile the thickness of residual myometrium is no less than 5.39 mm after vaginal repair. The final nomogram is constructed to predict surgical outcomes based on preoperative variables.

RESULTS

The key factors that determine optimal healing are the timing of cesarean section (elective or emergency), menstrual cycle, CSD length, width, depth, and the thickness of the lower uterine segment. With the prediction model, scores are given to each parameter according to the statistics. Total scores range from 0 to 25 points, with a cutoff point of 16.5. When a score is greater than 16.5, the transvaginal repair can achieve optimal healing. Uterine position (anteflexion or retroflexion) and preoperative thickness of residual myometrium are the key factors affecting postoperative thickness of residual myometrium. The width of the CSD and the thickness of the lower uterine segment are the key factors affecting abnormal uterine bleeding symptoms (p < 0.01).

CONCLUSIONS

For the first time, we established a prediction model system that may predict the repair effect of CSD and can potentially be useful in future clinical trials to determine which patients are more suitable for surgery or other treatment options.

Aetiology, risk factors and preventive strategies for niche development: A review

The increase in caesarean sections (CS) has resulted in an increase in women with a uterine niche. The exact aetiology of niche development has yet to be elucidated but is likely multifactorial. This study aimed to give a systematic overview of the available literature on histopathological features, risk factors and results of preventive strategies on niche development to gain more insight into the underlying mechanisms. Based on current published data histopathological findings associated with niche development were necrosis, fibrosis, inflammation, adenomyosis and insufficient approximation. Patient-related risk factors included multiple CS, BMI and smoking. Labour-related factors were CS before onset of labour, extended cervical dilatation, premature rupture of membranes and presenting part of the fetus at CS below the pelvic inlet. Preventive strategies should focus on the optimal level of incision, training of surgeons and full-thickness closure of the myometrium (single or double-layer) using non-locking sutures. Conflicting data exist concerning the effect of endometrial inclusion. Future studies without heterogeneity in population, using standardized performance of the CS after proper training and using standardized niche evaluation with a relevant core outcome set are required to allow meta-analyses and to develop evidence-based preventive strategies. These studies are needed to reduce the prevalence of niches and prevent complications in subsequent pregnancies such as caesarean scar pregnancies.

Prevalence, definition, and etiology of cesarean scar defect and treatment of cesarean scar disorder: A narrative review

Background

Cesarean scar defects (CSD) are caused by cesarean sections and cause various symptoms. Although there has been no previous consensus on the name of this condition for a long time, it has been named cesarean scar disorder (CSDi).

Methods

This review summarizes the definition, prevalence, and etiology of CSD, as well as the pathophysiology and treatment of CSDi. We focused on surgical therapy and examined the effects and procedures of laparoscopy, hysteroscopy, and transvaginal surgery.

Main findings

The definition of CSD was proposed as an anechoic lesion with a depth of at least 2 mm because of the varied prevalence, owing to the lack of consensus. CSD incidence depends on the number of times, procedure, and situation of cesarean sections. Histopathological findings in CSD are fibrosis and adenomyosis, and chronic inflammation in the uterine and pelvic cavities decreases fertility in women with CSDi. Although the surgical procedures are not standardized, laparoscopic, hysteroscopic, and transvaginal surgeries are effective.

Conclusion

The cause and pathology of CSDi are becoming clear. However, there is variability in the prevalence and treatment strategies. Therefore, it is necessary to conduct further studies using the same definitions.

Prediction of Scar Myometrium Thickness and Previous Cesarean Scar Defect Using the Three-Dimensional Vaginal Ultrasound

This research aimed to explore the related factors of scar myometrial thickness and scar diverticulum formation and then predict the occurrence of uterine diverticula. 140 patients with cesarean section were selected as the research objects. According to the three-dimensional (3D) vaginal ultrasound echo and the diagnostic criteria of uterine diverticulum, the research objects were divided into a diverticulum group and a control group, with 70 cases in each group. Data such as age, number of cesarean sections, endometrial thickness, uterine position, and diverticulum size was collected, and their relationship with uterine diverticulum was compared and analyzed. The results showed that there were significant differences in menstrual days, cesarean section times, and uterine position between the two groups (P < 0.05). The height (9.02 ± 2.97), width (14.02 ± 3.08), and depth (5.14 ± 1.23) of the posterior uterine diverticula in the scar diverticulum group were all greater than the anterior uterine height (6.69 ± 1.36), the width (10.69 ± 2.15), and the depth (3.86 ± 0.69), respectively. The residual myometrium thickness in posterior position of the uterus (2.98 ± 0.75) was < anterior position of uterus (3.43 ± 0.47), and the difference was statistically significant (P < 0.05). Multivariate analysis showed that the frequency of cesarean section (1 time, 2 times), uterine position, and abnormal menstruation were independent risk factors in the scar diverticulum group (P < 0.05). In conclusion, menstrual abnormalities, the number of cesarean sections (1 time or twice), and the position of the uterus are independent risk factors for the formation of uterine scar diverticula. The deeper the diverticula, the more likely to have menstrual abnormalities, the more prone to diverticulum in patients with posterior uterus, and the deeper the diverticula in patients with 2 dissections.