Ultrasound cesarean scar assessment one year postpartum in relation to one- or two-layer uterine suture closure

A prospective study on risk factors associated with the development of isthmocele after caesarean section

OBJECTIVES

The primary objective was to detect the number of women developing isthmocele following lower segment caesarean section. The secondary objectives included analysing the risk factors associated with developing isthmocele and measuring the agreement between Transvaginal Ultrasonography (TVS) and Saline infusion Sonohysterography (SIS) in diagnosing Isthmocele.

METHODS

This study was conducted in the Department of Obstetrics and Gynecology and focused on women who had undergone Lower Segment cesarean Section (LSCS). The study aimed to detect any indentation of at least 2 mm in the scar site, known as isthmocele, using Transvaginal Ultrasound (TVS) and Saline Infusion Sonography (SIS) between 6 weeks and 6 months after delivery. Along with the primary objective, the study also evaluated several secondary outcomes such as maternal comorbidities, closure techniques, and labor details. The evaluation of isthmocele followed the 2019 modified Delphi consensus approach.

RESULTS

In our study, we found that 30% of our study population had isthmocele. We also observed that the number of previous caesarean deliveries, maternal BMI, duration of surgery, and characteristics of the previous CD scar were significantly associated with the development of isthmocele. When we compared the diagnostic methods, we found that TVS and SIS had similar limits of agreement for clinically important isthmocele parameters. However, we noticed a difference in the length and distance of isthmocele from the internal os, which we observed through Bland Altman plots.

CONCLUSION

Our research has shown that women who have undergone multiple caesarean deliveries, have a higher maternal body mass index (BMI), and experienced longer surgery duration are at a significantly higher risk of developing isthmocele. To prevent its development, it is recommended to promote vaginal birth after caesarean delivery whenever feasible, manage maternal obesity early on, and provide adequate surgical training to medical professionals. Additionally, transvaginal ultrasound (TVS) is an effective method for detecting isthmocele and can be used interchangeably with saline-infused sonography (SIS).

Effects of endometrial versus non-endometrial suturing on isthmocele development; a randomized controlled trial

OBJECTIVE

Incomplete healing after cesarean section (CS) can result in isthmocele formation. When suturing the uterus, fully folding the wound lips may embed the endometrial layer into the myometrium, leading to isthmocele development. Hence, this study aimed to compare the effects of endometrial and non-endometrial suturing on isthmocele development.

MATERIAL AND METHODS

This randomized controlled trial included 274 patients. Women who underwent primary CS were randomly allocated to one of the two study groups: endometrial suturing and non-endometrial suturing. The primary outcome was isthmocele rate at postpartum 6 months. Secondary outcomes were the volume of the isthmocele, thickness of the residual myometrium, menstrual irregularities (intermenstrual spotting), and the relationship between the isthmocele and uterine position.

RESULTS

A total of 159 patients (81 in the endometrial suturing group and 78 in the non-endometrial suturing group) were analyzed. The incidence of isthmocele was significantly lower in the non-endometrial suturing group than in the endometrial suturing group (12 [15.4%] vs. 24 [29.6%] patients; p = 0.032). Menstrual irregularities, such as intermenstrual spotting, were significantly higher in the endometrial suturing group than in the non-endometrial group (p = 0.019).

CONCLUSION

Uterine closure with non-endometrial suturing was associated with significantly lower isthmocele development and less intermenstrual spotting compared to that with endometrial suturing.

The Novel Parallel Closure Technique Compared to Single-Layer Closure of the Uterus After Primary Cesarean Section Decreases the Incidence of Isthmocele Formation and Increases Residual Myometrial Thickness

Background Isthmocele or a scar defect is a relatively common consequence of cesarean section resulting in menstrual disturbances and infertility and may compromise the myometrial integrity of the uterus in women contemplating subsequent vaginal birth. Several preventive measures have been suggested, including the modification of surgical techniques used for the closure of the uterine incision. The current study aimed to compare the incidence of isthmocele and assess residual myometrial thickness in women who underwent single versus parallel layered closure to approximate the endo-myometrial layer during cesarean section. Methodology This retrospective study evaluated data of women undergoing their first cesarean section under elective conditions (n = 497) where the uterine incision was closed using a single (n = 295) or a parallel layer (n = 202) technique. Patients were evaluated twice, at 3-6 months and 18 months postpartum, with a transvaginal ultrasound noting the presence or absence of an isthmocele and measurement of the residual myometrial thickness. Results Regardless of the closure technique, 64 (12.9%) women had an ultrasound-diagnosed isthmocele. Significantly fewer patients in the parallel-layer closure group presented with an isthmocele both at 3-6 (13.6 vs. 6.9%; p = 0.019) and 18 months (16.3 vs. 7.8%; p = 0.009) postpartum. Residual myometrium was significantly thicker in the parallel-layer closure group (8.0 vs. 13.2 mm at 3-6 months postpartum; p = 0.000 and 7.2 vs. 12.3 mm at 18 months postpartum; p = 0.004). For all patients, a retroverted position of the uterus at 3-6 months follow-up examination significantly increased the frequency of isthmocele (36/395 (9.1%) with an anteverted uterus and 18/102 (17.6%) with a retroverted uterus; p = 0.002). In patients with a single-layer closure, a retroverted uterus at the 3-6-month follow-up was associated with an isthmocele in 29.5% (18/61) of patients, while no isthmocele was recorded when the uterus was retroverted in the parallel-layer closure group (0/41) (p = 0.001). At 18 months postpartum, of the 64 patients with an isthmocele, 26 (40.6%) presented with abnormal uterine bleeding mainly in the form of postmenstrual spotting. Of the 26 patients with abnormal bleeding, 23 were in the single-layer and three were in the parallel-layer closure group. Conclusions The parallel-layer closure when compared to a single-layer closure of the uterine incision in patients undergoing primary cesarean section decreased the incidence of isthmocele formation and increased residual myometrial thickness. More patients in the single-layer closure group had menstrual cycle disturbances at 18 months postpartum.

Predictive value of abdominal wall scar score for pelvic floor function rehabilitation, vaginal microecology and complications after cesarean section

Objective

To explore the predictive value of the abdominal wall scar score for pelvic floor function rehabilitation, vaginal microecology and complications after cesarean section.

Methods

A total of 120 pregnant women who underwent cesarean section in our hospital from January to December 2022 were selected. The patients were divided into observation group (score ≥ 60, n = 52) and control group (score < 60, n = 68) according to the preoperative score of abdominal wall scar and whether the score exceeded 60. The pelvic floor function rehabilitation, vaginal microecology and complications were compared between the two groups, and the score of abdominal wall scar was evaluated by receiver operating characteristic (ROC) curve. The predictive value of pelvic floor function rehabilitation, vaginal microecology and complications after cesarean section was evaluated.

Results

There were significant differences between the two groups in postpartum class I and class II muscle fiber strength and pelvic floor muscle potential (P < 0.05). ROC curve showed that the AUC of abdominal scar score in predicting pelvic floor function rehabilitation was 0.806 (95% CI [0.684-0.927]), the specificity was 80.17%, and the sensitivity was 79.76%. There was significant difference in the abnormal rate of leukocte estrase (LE) and Acetylaminoglucosidase (NAG) between the two groups (P < 0.05). ROC curve showed that the AUC of abdominal scar score in predicting vaginal microecology was 0.871 (95% CI [0.776-0.966]), the specificity was 85.09%, and the sensitivity was 82.36%. There was significant difference in the incidence of postpartum complications between the two groups (P < 0.05). ROC curve showed that the AUC of abdominal scar score in predicting complications was 0.844 (95% CI [0.735-0.953]), the specificity was 82.27%, and the sensitivity was 81.15%.

Conclusion

The abdominal scar score has a certain effect on predicting the recovery of pelvic floor function, vaginal microecology and complications after cesarean section. Therefore, it can help the medical staff to adjust the treatment measures in time, which can be used as a means of preoperative auxiliary examination.

Intra-operative Guidelines for the Prevention of Uterine Niche Formation in Cesarean Sections: A Review

Formation of a uterine niche following a C-section can predispose the patient to future obstetric complications such as dehiscence, uterine rupture, ectopic pregnancy, and placenta accreta. The significant morbidity and mortality of these complications along with increasing C-section rates emphasizes the importance of prevention. However, there are no clear guidelines on intra-operative protocol to prevent postpartum niche formation. Besides surgical technique, the novel use of platelet-rich plasma (PRP) and mesenchymal stem cell (MSC) injections has demonstrated promising potential and may have applications in hysterotomy closures. The objective is to examine current research on optimal C-section procedures to prevent uterine niche formation and subsequent obstetric complications. A systematic review was conducted using PubMed and Google Scholar. Initial searches yielded 827 results. Inclusion criteria were human, animal, and in-vitro studies, peer-reviewed sources, and outcomes pertinent to the uterine niche. Exclusion criteria applied to articles with outcomes unrelated to myometrium and interventions outside of the intra-operative and immediate pre-/post-operative period. Based on the criteria, 41 articles were cited. Pathophysiology of uterine niche formation was associated with incisions through cervical tissue, adhesion formation, and poor approximation. Significant risk factors were low uterine incisions, advanced cervical dilatation, low station, non-closure of the peritoneum, and creation of a bladder flap. There was no consensus on uterine closure as it likely depends on surgical proficiency with the given technique, but a double-layered non-locking suture appears reliable to reduce niche severity. Recent trials indicate that intra-operative PRP/MSC injections may decrease niche incidence and severity, but more research is needed. If prevention or minimization of uterine niche is desired, the optimal C-section protocol should avoid low uterine incisions, choose uterine closure technique based on the surgeon's proficiency (double-layered non-locking is reliable), and close the peritoneum, and myometrial injection of PRP/MSC may be a useful adjunct intervention pending further clinical evidence.

Effect of cervical changes on the cesarean scar area and niche formation after preterm and term cesarean sections

OBJECTIVE

The purpose of this study is to assess the scar area and niche formation after cesarean section in women who had preterm or term deliveries and underwent cesarean section at various stages of labor.

METHOD

This prospective cohort study consists of cases who underwent the first cesarean section for different obstetric reasons. The patients were divided into four groups regarding gestational age and cervical dilatation. After a cesarean section, all patients were called for vaginal ultrasonography control at 12 weeks. The location of the scar and the presence of a niche were evaluated. The residual (RMT), proximal, and distal myometrial thicknesses were evaluated where the scar and niche were located.

RESULTS

A total of 87 cases were included in the study. There was no difference in the prevalence of niche between the groups (p > 0.05). RMT and proximal and distal myometrial thickness were not different between the 37 ≥ week and 37 < week groups, while RMT and proximal and distal myometrial thickness were significantly lower in women with active labor (p =0.001, p= 0.006, p =0.016). The location of the scar was the isthmus at 37 weeks and above (p= 0.002), it was in the cervical canal in the group below 37 weeks (p= 0.017).

CONCLUSION

The gestational week and cervical changes did not affect the prevalence of the niche. In cases of active labor and preterm deliveries, the CS scar defect was located in the cervical canal; however, in cases of term deliveries, it was located in the isthmic area.

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.

[The cesarean procedure: Guidelines for clinical practice from the French College of Obstetricians and Gynecologists]

OBJECTIVE

To identify procedures to reduce maternal morbidity during cesarean.

MATERIAL AND METHODS

The quality of evidence of the literature was assessed following the GRADE® method with questions formulated in the PICO format (Patients, Intervention, Comparison, Outcome) and outcomes defined a priori and classified according to their importance. An extensive bibliographic search was performed on PubMed, Cochrane and EMBASE databases. The quality of the evidence was assessed (high, moderate, low, very low) and a (i) strong or (ii) weak recommendations or (iii) no recommendation were formulated. The recommendations were reviewed in two rounds with external reviewers (Delphi survey) to select the consensus recommendations.

RESULTS

Of the 27 questions, there was agreement between the working group and the external reviewers on 26. The level of evidence of the literature was insufficient to provide a recommendation on 15 questions. Preventing hypothermia is recommended to increase maternal satisfaction and comfort (weak recommendation) and to reduce neonatal hypothermia (strong recommendation). The quality of the evidence of the literature did not allow to recommend the skin disinfectant to be used nor the relevance of a preoperative vaginal disinfection nor the choice between the use or nonuse of an indwelling bladder catheterization (if micturition takes place 1 hour before the cesarean section). The Misgav-Ladach technique or its analogues should be considered rather than the Pfannenstiel technique to reduce maternal morbidity (weak recommendation) bladder flap before uterine incision should not be performed routinely (weak recommendation), but a blunt (weak recommendation) and cephalad-caudad extension of uterine incision (weak recommendation) should be considered to reduce maternal morbidity. Antibiotic prophylaxis is recommended to reduce maternal infectious morbidity (strong recommendation) without recommendation on its type or the timing of administration (before incision or after cord clamping). The administration of carbetocin after cord clamping does not significantly decrease the incidence of blood loss>1000 ml, anemia, or blood transfusion compared with the administration of oxytocin. Thus, it is not recommended to use carbetocin rather than oxytocin in cesarean. It is recommended that systematic manual removal of the placenta not to be performed (weak recommendation). An antiemetic should be administered after cord clamping in women having a planned cesarean under locoregional anaesthesia to reduce intraoperative and postoperative nausea and vomiting (strong recommendation) with no recommendation regarding choice of use one or two antiemetics. The level of evidence of the literature was insufficient to provide any recommendation concerning single or double-layer closure of the uterine incision, or the uterine exteriorization. Closing the peritoneum (visceral or parietal) should not be considered (weak recommendation). The quality of the evidence of the literature was not sufficient to provide recommendation on systematic subcutaneous closure, including in obese or overweight patients, or the use of subcuticular suture in obese or overweight patients. The use of subcuticular suture in comparison with skin closure by staples was not considered as a recommendation due to the absence of a consensus in the external review rounds.

CONCLUSION

In case of cesarean, preventing hypothermia, administering antiemetic and antibiotic prophylaxis after cord clamping are the only strong recommendations. The Misgav-Ladach technique, the way of performing uterine incision (no systematic bladder flap, blunt cephalad-caudad extension), not performing routine manual removal of the placenta nor closure of the peritoneum are weak recommendations and may reduce maternal morbidity.

Effect of single- and double-layer cesarean section closure on residual myometrial thickness and isthmocele - a systematic review and meta-analysis

Objective

To determine the incidence of isthmocele, its effect on residual myometrial thickness (RMT), and other complications of Cesarean delivery (CD) in relation to single- and double-layer CD closure. We searched PubMed, SCOPUS, Web of Science, ClinicalTrials.gov, MEDLINE and Cochrane Library for relevant clinical trials assessing the use of single- and double-layer uterine closure in patients undergoing cesarean sections from inception through to March 2021.

Materials and Methods

Our population was women undergoing cesarean section with uterine closure by any double-layer method, compared with those undergoing uterine closure through a single-layer method. RMT (in mm) was measured at 6 weeks, niche/isthmocele existence at 6 weeks, RMT (in mm) at 6-24 months and niche/isthmocele existence at 6-24 months. In order to present the highest quality evidence, we only included clinical trials in our analysis. To perform this review, we reported dichotomous outcomes using percent and total, while continuous outcomes were reported using mean ± standard deviations, and relative 95% confidence intervals using the inverse variance method.

Results

We found that the RMT in the double-layer closure group was significantly higher at six weeks [mean difference (MD)=-0.43 (-0.77, -0.09)], (p=0.01) and at 6-24 months of follow-up [MD=-1.27 (-2.28, -0.25)], (p=0.01). The incidence of isthmocele in the two groups, as well as the other investigated outcomes were similar across the different groups.

Conclusion

High-quality evidence shows that double-layer closure results in a higher RMT compared with a single-layer closure, despite no significant difference in isthmocele formation.

Single- Versus Double-Layer Uterine Closure After Cesarean Section Delivery: A Systematic Review and Meta-Analysis

Cesarean section (CS) delivery is a common procedure, and its incidence is increasing globally. To compare single-layer (SL) with double-layer (DL) uterine closure techniques after cesarean section in terms of ultrasonographic findings and rate of CS complications. PubMed, Scopus, Web of Science, and Cochrane Library were searched for relevant randomized clinical trials (RCTs). Retrieved articles were screened, and relevant studies were included in a meta-analysis. Continuous data were pooled as mean difference (MD) with 95% confidence interval (CI), and dichotomous data were pooled as relative risk (RR) and 95% CI. Analysis was conducted using RevMan software (Version 5.4). Eighteen RCTs were included in our study. Pooled results favored DL uterine closure in terms of residual myometrial thickness (MD = -1.15; 95% CI -1.69, -0.60; P < 0.0001) and dysmenorrhea (RR = 1.36; 95% CI 1.02, 1.81; P = 0.04), while SL closure had shorter operation time than DL closure (MD = -2.25; 95% CI -3.29, -1.21; P < 0.00001). Both techniques had similar results in terms of uterine dehiscence or rupture (RR = 1.88; 95% CI 0.63, 5.62; P = 0.26), healing ratio (MD = -5.00; 95% CI -12.40, 2.39; P = 0.18), maternal infectious morbidity (RR = 0.94; 95% CI 0.66, 1.34; P = 0.72), hospital stay (MD = -0.12; 95% CI -0.30, 0.06; P = 0.18), and readmission rate (RR = 0.95; 95% CI 0.64, 1.40; P = 0.78). Double-layer uterine closure shows more residual myometrial thickness and lower incidence of dysmenorrhea than single-layer uterine closure of cesarean section scar. But single-layer closure has the advantage of the shorter operation time. Both methods have comparable blood loss amount, healing ratio, hospital stay duration, maternal infection risk, readmission rate, and uterine dehiscence or rupture risk.

Ultrasound vs. histologic findings in 40 patients with special types of ectopic pregnancy

PURPOSE

The purpose of the study was to analyze the ultrasound findings and imaging features of patients with special types of ectopic pregnancy.

METHODS

The ultrasound findings of 40 patients with special types of ectopic pregnancy in our hospital were retrospectively analyzed.

RESULTS

Among 40 patients, there were 17 cases of corneal pregnancy, 12 cases of cervical pregnancy, 8 cases of uterine scar pregnancy, and 3 cases of incomplete abortion confirmed by operation and pathology. The accuracy rate of ultrasound findings in the diagnosis of 40 special types of ectopic pregnancy was 77.50%, with a consistency rate of 70.59% for cornual pregnancy, 83.33% for cervical pregnancy, 100.00% for cesarean scar pregnancy and 33.33% for incomplete abortion. There were 9 misdiagnoses in ultrasound diagnosis, including 5 misdiagnoses of angular pregnancy (misdiagnosed as 4 cases of tubal interstitial pregnancy and 1 case of trophoblastic tumor), 2 misdiagnoses of cervical pregnancy (misdiagnosed as incomplete abortion), and 2 misdiagnoses of incomplete abortion (misdiagnosed as isthmus pregnancy). There was no misdiagnosed case of cesarean scar pregnancy.

CONCLUSION

Ultrasound findings have some value in the diagnosis of specific types of ectopic pregnancy and can help identify different types of ectopic pregnancy. Transabdominal ultrasound and transvaginal ultrasound should be clinically combined to obtain more information for diagnosis.

[Cesarean scare niche: Definition, diagnosis, risk factors, prevention, symptoms, adverse effects, and treatments]

OBJECTIVES

To review the definitions, diagnostic methods, risk factors, symptoms, and treatments for caesarean scar niche.

METHODS

Review of the literature, critical reflection, and pragmatic advice.

RESULTS

There is no consensus on the definition of caesarean scar niche. Some suggest an indentation≥2mm of the myometrium of the caesarean scar, but this is present in more than half of women with caesarean history and takes no account of woman's symptoms. The most popular diagnostic method is ultrasound±hysterosonography. Risks factors for niche are multiple Caesareans, Cesarean during labor with too low incision, and retroverted uterus. Symptoms include abnormal gynaecologic bleeding and pelvic pain, and their presence establish the "Caesarean scar syndrome". The risks of pregnancy with niche is poorly studied, but pregnancy is not contraindicated, even if the niche is untreated. The treatment of caesarean scar niche is mainly surgery and conservative. The former should be reserved for symptomatic patients, and those with secondary infertility and fertility treatment failure. Patients with residual myometrium thickness≥2.5mm may benefit from first-line hysteroscopic treatment, whereas a laparoscopic or vaginal approach could be offered in other cases.

CONCLUSIONS

A pragmatic definition of caesarean scar niche as a disease including symptoms is the necessary prerequisite for the management of women. The treatment is mainly surgical, or conservative depending on the desire for subsequent pregnancy.

Potential risk factors for caesarean scar pregnancy: a retrospective case-control study

STUDY QUESTION

What are the important risk factors for having a caesarean scar pregnancy (CSP)?

SUMMARY ANSWER

Independent risk factors were smoking in the first trimester, higher parity, and previous caesarean section (CS) before the index caesarean delivery.

WHAT IS KNOWN ALREADY

A spectrum of risk factors for CSP has been suggested but not proven: parity, number of previous caesarean section, elective as opposed to emergency CS, IVF-pregnancy, breech presentation, previous gynaecological surgery as well as suture technique.

STUDY DESIGN SIZE DURATION

This retrospective case-control study included 31 women with a CSP during the period 2003-2018 treated at a tertiary care centre for gynaecology and reproduction. A control cohort of 8300 women with a history of a CS and a subsequent delivery during the same time period was formed.

PARTICIPANTS/MATERIALS SETTING METHODS

Variables describing demography, lifestyle factors, and reproductive and obstetric history were retrieved from medical records and the obstetric hospital database. Logistic regression analyses were applied to identify potential risk factors.

MAIN RESULTS AND THE ROLE OF CHANCE

In a multivariable analysis, smoking in first trimester (adjusted odds ratio (OR) 3.03, 95% CI 1.01-9.07), higher parity (adjusted OR 1.30, 95% CI 1.03-1.64) and previous CS in addition to the preceding CS (adjusted OR 3.43, 95% CI 1.35-8.66) were independently predictive of a CSP. An elective CS at the index pregnancy was associated with an increased risk of CSP but did not remain significant in the multivariable analysis.

LIMITATIONS REASONS FOR CAUTION

CSP is a very rare phenomenon and several of the risk factor estimates are imprecise. Nevertheless, significant risk factors could be identified. Another limitation is the lack of electronically recorded details on suture techniques.

WIDER IMPLICATIONS OF THE FINDINGS

The identified factors, namely higher parity and previous CS before the index caesarean section, are in accordance with previously suggested risk factors. Whether there is a true risk association between elective CS and future CSP needs to be investigated further. Smoking in the first trimester is a new finding, which has a plausible rationale. These factors should be recognised when counselling women after a caesarean delivery, particularly in a subsequent pregnancy with early complications.

STUDY FUNDING/COMPETING INTERESTS

This work was supported by a grant from the Swedish state under the agreement between the Swedish government and the county councils the ALF-agreement (ALFGBG-720291). None of the authors has any conflict of interest to declare.

Single- or double-layer uterine closure techniques following cesarean: A randomized trial

INTRODUCTION

Cesarean deliveries are commonly performed throughout the world. Although the uterine closure technique following this procedure may influence how the uterine scar heals, there is insufficient evidence for choosing the appropriate technique and so preventing long-term negative consequences. This prospective, randomized study examined the effects of single- and double-layer uterine closure techniques on uterine scar healing following cesarean delivery.

MATERIAL AND METHODS

This study assessed a total of 282 women aged 18-45 years who were in gestational weeks 24-41 of singleton pregnancies. None had previously undergone uterine surgeries. These participants completed their first cesarean deliveries at the time of study and were randomized into the following two treatment groups: single-layer closure with locking and double-layer closure with locking in the first layer, but not in the second layer (NCT03629028). However, the decidua was not included for treatment in either group. Participants were evaluated at 6-9 months after cesarean section by saline infusion sonohysterography to assess cesarean delivery scar defects. These procedures were conducted by experienced sonographers who were not aware of the uterine closure technique.

RESULTS

Of the 225 final participants, 109 received the single-layer closure technique, whereas 116 received the double-layer technique. The niche rates were 37% (n = 40) for the single-layer group and 45.7% (n = 53) for the double-layer group (P = .22, relative risk 1.4, 95% CI = 0.8-4.4).

CONCLUSIONS

The single- and double-layer closure techniques did not produce different impacts on uterine scar niche development.

Hydrosonographic Assessment of the Effect of Two Different Suture Materials on Healing of the Uterine Scar after Cesarean Delivery: A Prospective Randomized Controlled Trial

PURPOSE

This study aimed to compare the effects of two different suture materials, monofilament synthetic absorbable sutures versus multifilament synthetic absorbable sutures, on healing the uterine scar after a cesarean delivery.

METHODS

A total of 95 women between the ages of 18 and 40 who had undergone a primary cesarean section (CS) after the 38^th week of gestation. In Group I (n=48), continuous double-layer unlocked closure of the low transverse uterine incision was performed using monofilament synthetic absorbable sutures. In Group II (n=47), continuous double-layer unlocked closure of the low transverse uterine incision was performed using multifilament synthetic absorbable sutures. Six months after the operation, the integrity of the cesarean scar at the uterine incision site was assessed using hydrosonography. The healing ratio and the thickness of the residual myometrium covering the defect were calculated as markers of uterine scar healing.

RESULTS

No statistically significant differences were observed between the groups with regard to the preoperative hemoglobin concentrations, the change in the hemoglobin concentrations, operating time, and the number of intraoperative additional hemostatic uterine sutures. Mean thickness of the residual myometrium covering the defect was thicker in the monofilament suture group in comparison to the multifilament suture group (7.76±2.11 vs. 5.96±1.69, respectively; p<0.01). The mean healing ratio was significantly higher in the monofilament suture group in comparison to the multifilament suture group (0.76±0.13 vs. 0.60±0.12, respectively; p<0.01) CONCLUSION: Continuous double-layer unlocked closure of the uterine incision at cesarean delivery using monofilament synthetic absorbable sutures decreases the risk of CS scar defect.

Ultrasound cesarean scar assessment one year postpartum in relation to one- or two-layer uterine suture closure

INTRODUCTION

This study compared healing of the scars after cesarean section during the first postpartum year using a single- or double-layer suturing technique. Scarring was assessed by a transvaginal ultrasound. We explored the appearance and localization of uterine scars with regard to the obstetric history. Our aim was to compare the position of the scar or defect, if present, its dimensions, and any residual myometrium with respect to the suturing technique during the cesarean section.

MATERIAL AND METHODS

Women with uncomplicated singleton pregnancies indicated for elective or acute cesarean section were randomly allocated to the uterine closure technique group. During the first postpartum year, their lower uterine segment was examined with a transvaginal ultrasound in three consecutive visits at 6 weeks, 6 months and 12 months.

RESULTS

324 women attended the 12-month visit; of these, 149 underwent single-layer closure of the uterine incision and 175 double-layer technique. A higher proportion of the defects is seen in the single-layer closure technique of suturing. Defects in the single-layer group were wider (0.002) and the residual myometrial thickness in the single-layer group were thinner (0.019). Women who underwent cesarean section at the stage of full cervical dilation had scars that were closer to the external cervical os (0.000). The position of the uterus varies greatly between controls (0.000). The combination of uterine position and scar defect presence changed significantly between controls (0.001), and was significantly dependent on the suturing method (0.003). Defects with or without contact with the uterine cavity changed statistically between controls (0.017). Both types of defects were more common in the single-layer closure technique group.

CONCLUSIONS

The findings of this study demonstrate that double-layer technique with the first continuous nonlocking suture followed by a second continuous nonlocking suture is associated with better suture healing and greater residual myometrial thickness. No difference was observed between single- and double-layer closure for the presence of maternal infectious morbidity, wound infection or blood transfusion.