Trial of labor after cesarean, vaginal birth after cesarean, and the risk of uterine rupture: an expert review

The decision to pursue a trial of labor after cesarean delivery is complex and depends on patient preference, the likelihood of successful vaginal birth after cesarean delivery, assessment of the risks vs benefits of trial of labor after cesarean delivery, and available resources to support safe trial of labor after cesarean delivery at the planned birthing center. The most feared complication of trial of labor after cesarean delivery is uterine rupture, which can have catastrophic consequences, including substantial maternal and perinatal morbidity and mortality. Although the absolute risk of uterine rupture is low, several clinical, historical, obstetrical, and intrapartum factors have been associated with increased risk. It is therefore critical for clinicians managing patients during trial of labor after cesarean delivery to be aware of these risk factors to appropriately select candidates for trial of labor after cesarean delivery and maximize the safety and benefits while minimizing the risks. Caution is advised when considering labor augmentation and induction in patients with a previous cesarean delivery. With established hospital safety protocols that dictate close maternal and fetal monitoring, avoidance of prostaglandins, and careful titration of oxytocin infusion when induction agents are needed, spontaneous and induced trial of labor after cesarean delivery are safe and should be offered to most patients with 1 previous low transverse, low vertical, or unknown uterine incision after appropriate evaluation, counseling, planning, and shared decision-making. Future research should focus on clarifying true risk factors and identifying the optimal approach to intrapartum and induction management, tools for antenatal prediction, and strategies for prevention of uterine rupture during trial of labor after cesarean delivery. A better understanding will facilitate patient counseling, support efforts to improve trial of labor after cesarean delivery and vaginal birth after cesarean delivery rates, and reduce the morbidity and mortality associated with uterine rupture during trial of labor after cesarean delivery.

First-trimester uterine rupture in a twin gestation after a motor vehicle collision: a case report

Uterine rupture following trauma in pregnancy is rare, especially in earlier gestational ages. The diagnosis can be challenging, and treatment may be delayed when patients present with nonspecific findings. Therefore, a high index of suspicion must be maintained. Once diagnosed, the treatment involves surgical exploration. We present a case report of a first-trimester uterine rupture of a twin pregnancy following a motor vehicle collision in a patient with prior cesarean sections.

Evaluation of preoperative ultrasound signs associated with bladder injury during complex Cesarean delivery: case-control study

OBJECTIVE

Intraoperative hemorrhage and peripartum hysterectomy are the main complications in patients presenting with a low-lying placenta or placenta previa undergoing repeat Cesarean delivery (CD). Patients with a high probability of placenta accreta spectrum (PAS) at birth also have a higher risk of intraoperative urologic injury. The aim of this study was to evaluate the ultrasound signs and intraoperative features associated with these injuries.

METHODS

This was a retrospective case-control study of consecutive singleton pregnancies included in a prospective cohort of patients with a history of at least one prior CD and diagnosed prenatally with an anterior low-lying placenta or placenta previa at 32-36 weeks' gestation. All patients underwent investigational preoperative transabdominal and transvaginal ultrasound examination within 48 h prior to delivery. Ultrasound anomalies of uterine contour and uteroplacental vascularity, and gross anomalies of the lower uterine segment (LUS) and surrounding pelvic tissue at delivery, were recorded using a standardized protocol, which included evaluation of the extent of uterine contour anomalies. The diagnosis of PAS was established when one or more placental lobules could not be separated digitally from the uterine wall at delivery or during the gross examination of the hysterectomy or partial myometrial resection specimens, and was confirmed by histopathology. Data were compared between cases complicated by intraoperative bladder injury and controls from the same cohort matched at a 1:3 ratio by parity and the number of prior CDs using conditional logistic regression.

RESULTS

There were 16 (9.4%) patients with an intraoperative bladder injury in a cohort of 170 managed by the same multidisciplinary team during the study period. There were no patients diagnosed with ureteric or bladder trigone damage. There were 14 (87.5%) patients with a bladder injury that had histopathologic evidence of PAS at birth, including 11 (68.8%) cases described on microscopic examination as placenta increta and three (18.8%) as placenta creta. There was a significant (P = 0.03) difference between cases and controls in the distribution of the intraoperative LUS vascularity, whereby the higher the number of enlarged vessels, the higher the odds of bladder injury. Multivariable regression analysis revealed that both gestational age at delivery and LUS remodeling on transabdominal ultrasound were associated with bladder injury. A longer gestational age was associated with lower risk of injury. A higher LUS remodeling grade on transabdominal ultrasound was associated with an increased risk of bladder injury. Patients with Grade-3 remodeling (involving > 50% of the LUS) had 9-times higher odds of a bladder injury compared to patients with Grade-1 remodeling (involving < 30% of the LUS).

CONCLUSIONS

Preoperative ultrasound examination is useful in the evaluation of the risk of intraoperative bladder injury in patients with a history of prior CD presenting with a low-lying placenta or placenta previa. The larger the remodeling of the LUS on transabdominal ultrasound, the higher the risk of adverse urologic events. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Repair of a chronic myometrial defect with successful pregnancy outcome

OBJECTIVE

To surgically demonstrate preconceptional laparoscopic repair of a chronic myometrial defect with mesh reinforcement, resulting in a successful pregnancy outcome.

DESIGN

Video case report. The Institutional Ethical Committee was consulted, and the requirement for approval was waived because the video describes a modified surgical technique. The patient included in this video gave consent for publication of the video and posting of the video online, including on social media, the journal website, scientific literature websites (such as PubMed, ScienceDirect, Scopus, and others), and other applicable sites.

SETTING

A referral advanced gynecological endoscopy center.

PATIENT

A 27-year-old woman (P0A1) was diagnosed with myomas during pregnancy, resulting in miscarriage at 22 weeks. Laparotomy and myomectomy were performed 2 months later, and three 8-cm myomas were removed. The endometrial cavity opened posteriorly during surgery, and retained products of conceptions were removed. Periconceptional imaging done after two years showed few intramural myomas and a deficient myometrium in the posterior fundal region. Laparoscopy revealed a defect in the posterior fundal aspect of the uterus with leakage of dye, which was converted to laparotomy and myomectomy with the repair of the myometrial defect. After 1 year, follow-up magnetic resonance imaging showed thinned-out posterior myometrium with a focal area of absent myometrium in the midline and endometrial prolapse. The patient was advised on surrogacy, but she wanted to repair the defect again and try for pregnancy, so she was referred to our center. With the background of a few case reports using mesh to reinforce myometrial repair (1, 2), we counseled the patient about the myometrial repair with the additional use of mesh as an off-label use.

INTERVENTION

The risk of uterine rupture after myomectomy is rare (<1%) (3), but it is a severe complication. High-risk cases, like significant myometrial defects or previous ruptures, may require surgical correction. Native repair may not achieve optimal results in all cases. Alternative approaches, like the additional use of mesh or biological materials, have been reported (4). In this case, we demonstrate the use of dual mesh for scar repair. Synthetic mesh over the uterus is used in laparoscopic procedures like sacrohysteropexy and cerclage. We used Parietex (Covidien, New Haven, CT, USA) mesh, a composite macroporous polyester mesh usually used for ventral hernia repair. It has an outer hydrophilic, absorbable collagen barrier that reduces adhesion formation. Laparoscopically, after adhesiolysis, a significant defect was demonstrated on the posterior wall of the uterus (Fig. 1). A complete resection of the fibrotic tissue along the edges of the scar defect was done to expose healthy myometrium. Myometrium was repaired in two layers, excluding the endometrium, with a V-Loc (Covidien, Dublin, Ireland) No. 1-0 suture. Parietex mesh was sutured over the repaired posterior myometrium to reinforce it (Fig. 2).

MAIN OUTCOME MEASURES

The postoperative myometrial thickness on imaging and pregnancy outcome.

RESULTS

Postoperative ultrasound scan after 6 weeks demonstrated restoration of posterior wall myometrial thickness of 14 mm. The patient was conceived through in vitro fertilization techniques 4 months after surgery. Antenatal follow-up was uneventful except for suspicion of posterior placenta accreta. She underwent an elective cesarean section with uterine artery embolization at 34 weeks and delivered a healthy infant weighing 1,950 g. Placental removal was uneventful. On inspection, the posterior surface of the uterus was intact without dehiscence, meshing in situ with minimal adhesions (Fig. 3).

CONCLUSION

Myometrial scar defects can cause potential obstetric complications. Native repair of scar defects may not achieve optimal results, as in our case. Mesh repair of myomectomy scar defects can be used as an alternative approach, as exemplified in this case. However, further studies are required to establish the safety and efficacy of this approach.

Uterine Dehiscence in the Early Third Trimester: A Report of Two Cases

As the incidence of cesarean deliveries increases, so do its accompanying complications. Although the incidence of uterine dehiscence in the late second trimester to the early third trimester is rare, it may be a potentially catastrophic complication if uterine rupture occurs. Here, we present two cases of uterine dehiscence at 28 and 29 weeks, which were diagnosed on prenatal ultrasound and confirmed intraoperatively at the time of cesarean delivery. We recommend consideration of earlier screening for preoperative detection of uterine dehiscence to help prevent maternal and neonatal morbidity and mortality.

Prospective evaluation of impact of post-Cesarean section uterine scarring in perinatal diagnosis of placenta accreta spectrum disorder

OBJECTIVE

Standardized ultrasound imaging and pathology protocols have recently been developed for the perinatal diagnosis of placenta accreta spectrum (PAS) disorders. The aim of this study was to evaluate prospectively the effectiveness of these standardized protocols in the prenatal diagnosis and postnatal examination of women presenting with a low-lying placenta or placenta previa and a history of multiple Cesarean deliveries (CDs).

METHODS

This was a prospective cohort study of 84 consecutive women with a history of two or more prior CDs presenting with a singleton pregnancy and low-lying placenta/placenta previa at 32-37 weeks' gestation, who were referred for perinatal care and management between 15 January 2019 and 15 December 2020. All women were investigated using the standardized description of ultrasound signs of PAS proposed by the European Working Group on abnormally invasive placenta. In all cases, the ultrasound features were compared with intraoperative and histopathological findings. Areas of abnormal placental attachment were identified during the immediate postoperative gross examination and sampled for histological examination. The data of a subgroup of 32 women diagnosed antenatally as non-PAS who had complete placental separation at birth were compared with those of 39 cases diagnosed antenatally as having PAS disorder that was confirmed by histopathology at delivery.

RESULTS

Of the 84 women included in the study, 42 (50.0%) were diagnosed prenatally as PAS and the remaining 42 (50.0%) as non-PAS on ultrasound examination. Intraoperatively, 66 (78.6%) women presented with a large or extended area of dehiscence and 52 (61.9%) with a dense tangled bed of vessels or multiple vessels running laterally and craniocaudally in the uterine serosa. A loss of clear zone was recorded on grayscale ultrasound imaging in all 84 cases, while there was no case with bladder-wall interruption or with a focal exophytic mass. Myometrial thinning (< 1 mm) in at least one area of the anterior uterine wall was found in 41 (97.6%) of the 42 cases diagnosed as non-PAS on ultrasound and 37 (88.1%) of the 42 diagnosed antenatally as PAS. Histological samples were available for all 48 hysterectomy specimens with abnormal placental attachment and for the three cases managed conservatively with focal myometrial resection and uterine reconstruction. Villous tissue was found directly attached to the superficial myometrium (placenta creta) in six of these cases and both creta villous tissue and deeply implanted villous tissue within the uterine wall (placenta increta) were found in the remaining 45 cases. There was no evidence of percreta placentation on histology in any of the PAS cases. Comparison of the main antenatal ultrasound signs and perioperative macroscopic findings between the two subgroups correctly diagnosed antenatally (32 non-PAS and 39 PAS) showed no significant difference with respect to the distribution of myometrial thinning and the presence of a placental bulge on ultrasound and of anterior uterine wall dehiscence intraoperatively. Compared with the non-PAS subgroup, the PAS subgroup showed significantly higher placental lacunae grade (P < 0.001) and more often hypervascularity of the uterovesical/subplacental area (P < 0.001), presence of bridging vessels (P = 0.027) and presence of lacunae feeder vessels (P < 0.001) on ultrasound examination, and increased vascularization of the anterior uterine wall intraoperatively (P < 0.001).

CONCLUSIONS

Remodeling of the lower uterine segment following CD scarring leads to structural abnormalities of the uterine contour on both ultrasound examination and intraoperatively, independently of the presence of accreta villous tissue on microscopic examination. These anatomical changes are often reported as diagnostic of placenta percreta, including cases with no histological evidence of PAS. Guided histological examination could improve the overall diagnosis of PAS and is essential to obtain evidence-based epidemiologic data. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Uterine Dehiscence: A Rare Cause of Postpartum Puerperal Sepsis

Uterine dehiscence (partial or complete) is a rare complication of lower segment cesarean section (LSCS). Puerperal sepsis with intra-abdominal abscess following this event has been rarely reported. The delay in diagnosis and management of the condition can result in significant morbidity and mortality. We herein report three cases of puerperal sepsis along with intra-abdominal abscess associated with uterine dehiscence following LSCS. These patients in the current case series presented with complaints of fever and abdominal pain. Early recognition and prompt treatment with diagnostic laparoscopy and or laparotomy with drainage were effective in the management of these patients.

Late Presentation of Uterine Rupture Following Vaginal Birth After Cesarean Delivery: A Case Report

Background  A trial of labor after cesarean delivery is associated with uterine rupture rates of 0.5 to 0.9%, which can have devastating neonatal and maternal consequences. While uterine rupture typically occurs during labor, it can clinically manifest after delivery. Case  A 23-year-old multiparous female presented in labor at term. Her obstetrical history was significant for a prior low transverse cesarean delivery. She had an uncomplicated labor course and spontaneous vaginal delivery. Immediately after delivery, she complained of severe right shoulder and left lower quadrant pain. Bedside ultrasound revealed a 10-cm, complex, adnexal mass adjacent to the uterus without free fluid. She was hemodynamically stable and appeared clinically well. On repeat ultrasound, the mass was unchanged; however, the patient now had free intraperitoneal fluid along the liver edge. Emergent laparotomy revealed a uterine rupture along her prior hysterotomy with extension into the right uterine artery. A 10-cm broad ligament hematoma ruptured posteriorly resulting in a 1-L hemoperitoneum. She received multiple blood products intraoperatively and recovered well postpartum. Conclusion  Delivery after trial of labor after cesarean delivery usually decreases acuity; however, these patients remain at risk for significant complications. Clinicians should continue to assess patients in the immediate postpartum period and proceed with surgical intervention if necessary.

Early prenatal detection of anterior uterine sacculation resulting from previous cesarean sections

Anterior uterine sacculation was diagnosed at 15 weeks of gestation in a woman with two previous cesarean sections, based on hourglass appearance of two distinct uterine segments, namely the empty upper segment and the large thinned wall lower segment containing a fetus with posteriorly attached placenta. The pregnancy developed through the bulging weakened anterior wall instead of growing toward the upper segment. Urgent hysterectomy was performed. The operative and pathological findings confirmed the prenatal ultrasound findings. This is the first report of prenatal diagnosis of sacculation due to cesarean section, which prevented the catastrophic event of uterine rupture.

Conservative Management of Infected Postpartum Uterine Dehiscence after Cesarean Section

There is an increase in cesarean rates worldwide. Parallel to this, the complications increased. Among these complications, uterine dehiscence and pelvic hematoma with abscess collection have increased. Diagnosis using methods such as ultrasonography, magnetic resonance imaging, and computer-aided tomography can be made. Treatment includes resuturing the uterine incision line, hysterectomy, or conservative treatment accompanied by broad-spectrum antibiotics administration. We evaluated three cases that were diagnosed by ultrasound as a dehiscent scar postpartum after cesarean section and they were managed conservatively with regular follow-up.

Underreporting of complete uterine rupture and uterine dehiscence in women with previous cesarean section

OBJECTIVE

To determine the true incidence of complete uterine rupture and uterine dehiscence among women delivered by cesarean section after a previous cesarean section.

METHODS

Medical records of all women who delivered at University Hospital in Malmö, Sweden, during 2005-2009 (n = 21 420) were retrieved from the electronic patient record system (EPRS). After adjustment for inaccuracies, 716 women who had undergone repeat cesarean section were identified and their operation reports were reviewed. Descriptions of complete uterine rupture or uterine dehiscence in operation reports were compared with diagnoses registered in EPRS with International Classification of Diseases codes version 10 (ICD-10). Sensitivity and specificity of complete uterine rupture registration were calculated.

RESULTS

There were 13 women with a registered diagnosis of uterine rupture. After reviewing medical records of women with repeat cesarean section, seven additional cases of complete uterine rupture, 33 cases of uterine dehiscence and 39 cases of extremely thin myometrium were identified. The incidence of complete uterine rupture and uterine dehiscence for women who delivered by repeat cesarean section was 2.8% and 10.1%, respectively.

CONCLUSIONS

Diagnosis of complete uterine rupture was underreported in the EPRS by 35% and diagnosis of uterine dehiscence was missing in 100% of cases.

[Spontaneus delivery after two previous caesarean sections - case report]

OBJECTIVE

To demonstrate the higher risk of the uterine dehiscence/rupture in spontaneously delivering women with scared uterus.

DESIGN

Case report.

SETTING

Department of Obstetrics and Gynecology, General Teaching Hospital in Prague and First Medical School, Charles University.

CASE REPORT

We demonstrate the risk of uterine dehiscence on the example of 36 year-old woman with two previous caesarean sections who decided to give birth spontaneously.

CONCLUSION

The scars on uterus are the risk factor for uterine dehiscence and rupture. In present, the rising number of caesarean sections leads to increasing number of women with scars on uterus. Despite the potential risk of scars on the uterus, small number of women with history of surgery on uterus plans to give birth spontaneously. We demonstrate the higher risk of the uterine dehiscence after spontaneous delivery in woman with history of two caesarean sections and successful conservative therapy.

Sonographic diagnosis of spontaneous uterine rupture at the site of cornual wedge resection scar - a case report

Introduction: Uterine rupture and uterine dehiscence during pregnancy are known complications of a scarred uterus. Spontaneous uterine rupture at the site of prior cornual wedge resection has been previously reported in the literature, however remains rare.

Discussion: We present a case of uterine rupture at 30 weeks gestation. This woman had previous right sided interstitial pregnancy treated with uncomplicated laparoscopic cornual wedge resection at eight weeks gestation. The index pregnancy occurred eight months after surgery. An emergency ultrasound prompted by non‐specific abdominal pain and tenderness at 30 weeks gestation enabled diagnosis of uterine dehiscence. At emergency caesarean section four hours later full thickness wall rupture and haemoperitoneum were found. Surgical intervention resulted in a good outcome for both mother and baby.

Conclusion: A brief account on uterine rupture in late pregnancy and relevant sonographic features related to this case are presented. This case demonstrates the value of ultrasound in the assessment of subtle clinical signs and symptoms in patients at risk of uterine rupture.

Prediction of uterine dehiscence using ultrasonographic parameters of cesarean section scar in the nonpregnant uterus: a prospective observational study

BACKGROUND

Every year 1.5 million cesarean section procedures are performed worldwide. As many women decide to get pregnant again, the population of pregnant women with a history of cesarean section is growing rapidly. For these women prediction of cesarean section scar performance is still a serious clinical problem.

METHODS

Starting in 2005, the study included 308 nonpregnant women with a history of low transverse cesarean section. The following ultrasonographic parameters of the cesarean section scar in the nonpregnant uterus were assessed: the residual myometrial thickness (RMT) and the width (W) and the depth (D) of the triangular hypoechoic scar niche. During 8 years of follow-up, 41 of these women were referred to our department for delivery. In all cases, a repeat cesarean section was performed and the lower uterine segment was assessed. Two independent statistical methods namely the logit model and Decision Tree analysis were used to determine the relation between the appearance of the cesarean section scar in the nonpregnat state and the performance of the scar in the next pregnancy.

RESULTS

The logit model revealed that the D/RMT ratio showed significant correlation with cesarean section scar dehiscence (P-value of 0.007). Specifically, a D/RMT ratio value greater than 1.3035 indicated that the likelihood of dehiscence was greater than 50%. The Decision Tree analysis revealed that a diagnosis of dehiscence versus non-dehiscence could be based solely on one criterion, a D/RMT ratio of at least 0.785. The sensitivity of this method was 71%, and the specificity was 94%.

CONCLUSIONS

Assessment of the cesarean section scar in the nonpregant uterus can be used to predict the occurrence of scar dehiscence in the next pregnancy.