European Journal of Cardiovascular Medicine

Cesarean scar pregnancy (CSP) is a rare and potentially dangerous type of ectopic pregnancy where the embryo implants within the scar of a previous cesarean section.¹This abnormal implantation can lead to severe clinical risks, including significant hemorrhage, uterine rupture, and potential loss of fertility, necessitating prompt diagnosis and management. CSP occurs when the blastocyst implants into the myometrium at the site of a previous cesarean scar.² This location provides a less optimal environment for implantation, often resulting in poor placental development and an increased risk of abnormal placental attachment, such as placenta accreta. The implantation can invade deeply into the myometrium and even through the uterine serosa, leading to potentially life-threatening complications.^2,3 Early and accurate diagnosis is crucial for effectively managing CSP. Transvaginal ultrasound (TVUS) is the primary diagnostic tool, capable of identifying specific features such as the gestational sac located at the cesarean scar, a thin or absent myometrial layer between the bladder and the sac, and increased vascularity at the implantation site as shown by color Doppler imaging. A new ultrasound grading system for Cesarean Scar Pregnancy (CSP) has been introduced to enhance diagnosis and treatment planning.⁴ This system categorizes CSP based on the gestational sac's position and depth in relation to the cesarean scar, vascularity, and fetal cardiac activity. Grade I (low risk) involves a sac at the scar with minimal penetration, low vascularity, and no fetal cardiac activity. Grade II (moderate risk) includes a partially embedded sac with moderate vascularity, possibly with fetal cardiac activity. Grade III (high risk) features a deeply embedded sac with extensive vascularity and clear fetal cardiac activity, indicating a high risk of severe complications. This system helps clinicians evaluate CSP severity, choose appropriate management strategies, and predict potential complications.

Grade I: CSP is embedded in less than half the lower anterior corpus. Grade II: CSP occupies more than half the thickness. Grade III: The gestational sac (GS) bulges out of the myometrium and uterine serosa. Grade IV: The GS appears as an amorphous tumor with rich vascularity at the cesarean scar.

MRI may also be used for more detailed imaging and to assess the extent of myometrial invasion. Patients with CSP may present with various symptoms, including vaginal bleeding, which may be light or heavy, and pelvic pain or discomfort. Some patients may show signs of early pregnancy, such as a positive pregnancy test, while others might be asymptomatic, with CSP discovered incidentally during early pregnancy scan.⁴

Management strategies for CSP vary depending on the gestational age, the patient's hemodynamic stability, and the desire for future fertility. Medical treatment is one of the most commonly employed methods for addressing cesarean scar pregnancy (CSP). Among the available medications, methotrexate (MTX) is the most frequently utilized due to its established history in treating ectopic pregnancies.^5,6 MTX functions as a folic acid antagonist, inhibiting the enzyme dihydrofolate reductase and thereby disrupting DNA synthesis in rapidly dividing cells, such as trophoblasts . Despite its common use, MTX as a first-line treatment for CSP is often associated with a relatively low success rate, ranging between 50% and 60%.^7-9Consequently, additional interventions, including surgical procedures, are frequently required. Surgical management options include dilatation and curettage (D&C), performed under ultrasound guidance to ensure complete removal of the pregnancy tissue, hysteroscopy for minimally invasive visualization and removal, and laparoscopy or laparotomy in cases of severe invasion or failure of other methods. Combined approaches may involve uterine artery embolization (UAE) to reduce blood flow to the pregnancy site before surgical removal to minimize bleeding risks. Curettage is typically the first choice following MTX therapy due to its convenience and cost-effectiveness. Several studies have suggested that MTX followed by curettage may represent an optimal treatment approach for CSP.^10,11 However, other research indicates that combining MTX with curettage can lead to increased blood loss, prolonged hospitalization, and a delayed return to normal β-human chorionic gonadotropin levels.¹² These mixed findings highlight the need for further investigation to determine the most effective and safest treatment protocols for CSP. The present study aims to assess the success and complications of medical and surgical modalities used in the treatment of cesarean scar pregnancies. This research seeks to evaluate the efficacy of these treatments in resolving CSP and to identify any associated complications, providing a comprehensive analysis of the best practices for managing this complex condition.

This prospective observational study was conducted in the Department of Gynecology at Lala Ded Hospital, GMC Srinagar, to evaluate the management strategies and outcomes of cesarean scar pregnancies (CSP) over a one-year period, from March 2023 to February 2024. The study aimed to enroll all eligible patients diagnosed with CSP during this timeframe. Patients eligible for inclusion were those diagnosed with CSP based on specific ultrasound criteria, including the absence of a gestational sac in the uterine and cervical canal, presence of a gestational sac embedded in the hysterotomy scar, presence of a fetal pole with or without yolk sac and fetal cardiac activity, thin or absent myometrial layer between the bladder and uterus, and discontinuity of the anterior uterine wall in the sagittal view. Data were collected prospectively through direct patient interviews, clinical examinations, and diagnostic imaging. Variables recorded included demographic characteristics (age, parity, gravidity), medical histories (previous ectopic pregnancies, cesarean deliveries), beta-human chorionic gonadotropin (beta-hCG) levels, route and timing of prior deliveries, indications for previous cesarean deliveries, treatment modalities (medical: methotrexate (MTX); surgical: dilation and curettage (D&C), laparotomy), complications, and subsequent obstetric outcomes.

Upon diagnosis, patients were managed according to standard clinical protocols and individualized patient needs. Medical treatment primarily involved MTX administration, while surgical interventions included D&C or laparotomy. Patients selected for medical management, primarily involving methotrexate (MTX), were those deemed suitable based on specific criteria. Medical management was typically offered to patients with stable hemodynamics, low beta-human chorionic gonadotropin (beta-hCG) levels, absence of fetal cardiac activity, and no evidence of active bleeding or hemoperitoneum on ultrasound evaluation. The rationale for choosing medical management included its non-invasive nature and potential to avoid surgical risks, especially in patients desiring fertility preservation. Surgical interventions, such as dilation and curettage (D&C) or laparotomy, were recommended for patients who did not meet the criteria for medical management or who failed to respond adequately to MTX therapy. Surgical treatment was preferred in cases of hemodynamic instability, high beta-hCG levels, presence of fetal cardiac activity, active bleeding, or signs of rupture or imminent rupture of the scar on ultrasound examination.  Patients who did not respond favorably to initial medical management with MTX were subsequently evaluated for surgical intervention, with the choice between D&C and laparotomy based on individual clinical indications and surgeon preference. D&C was typically chosen for patients with relatively stable hemodynamics and accessible CSP locations, while laparotomy was reserved for cases requiring more extensive tissue removal or suspected complications. Patients were monitored closely throughout their treatment course with serial beta-hCG measurements, repeat ultrasound evaluations, and assessment for complications. Follow-up assessments were conducted via outpatient visits and telephone consultations to ensure comprehensive data collection and patient compliance. The study protocol was reviewed and approved by the Institutional Ethics Committee of GMC Srinagar. Informed consent was obtained from all participants before inclusion in the study. Patient confidentiality and data privacy were strictly maintained throughout the research process. This comprehensive methodology ensured a thorough and systematic investigation into the management and outcomes of cesarean scar pregnancies. The findings from this study aim to contribute valuable insights into the optimal treatment strategies for CSP and enhance patient care protocols.

Statistical Methods:

The recorded data was compiled and entered in a spreadsheet (Microsoft Excel) and then exported to data editor of SPSS Version 20.0 (SPSS Inc., Chicago, Illinois, USA). Continuous variables were expressed as Mean±SD and categorical variables were summarized as frequencies and percentages. Graphically the data was presented by bar and pie diagrams. The Shapiro-Wilk test was applied to test the normality of data. Student’s independent t-test or Mann-Whitney U-test, whichever feasible, was employed for comparing continuous variables. Chi-square test or Fisher’s exact test, whichever appropriate, was applied for comparing categorical variables. A P-value of less than 0.05 was considered statistically significant.

In this section, the results of the study, will be described:

Out of a total of 45 individuals, 6 participants (13.3%) were aged between 20-24 years, 13 participants (28.9%) were in the 25-29 year age group, 19 participants (42.2%) fell within the 30-34 year age range, and 7 participants (15.6%) were aged 35 years and older. The mean age of the participants was 32.8 years, with a standard deviation of 4.57 years, and the ages ranged from 23 to 40 years.  Among the 45 patients included in the study, 15 were classified as Gravida 2, representing 33.3% of the total. The largest group comprising 21 patients or 46.7%, were classified as Gravida 3. The remaining 9 patients, accounting for 20.0% of the study population, were classified as Gravida 4 or higher.

The distribution of previous lower segment cesarean sections (LSCS) among the study revealed that 18 patients, accounting for 40.0% of the total, had one previous LSCS. A larger group of 22 patients, representing 48.9%, had undergone two prior LSCS. Finally, 5 patients, making up 11.1% of the study population, had three previous LSCS.

The table 1 provides an overview of the previous ectopic pregnancy history among patients with cesarean scar pregnancies. It shows that 4.4% of these patients had experienced tubal pregnancies, while 2.2% had a previous cesarean scar pregnancy. Notably, the vast majority (93.3%) had no prior history of ectopic pregnancies. These findings indicate that while a small percentage of patients had a history of ectopic pregnancies, most were encountering a cesarean scar pregnancy for the first time. This information is essential for understanding patient backgrounds and tailoring treatment approaches accordingly.

A total of 35.6% of patients were treated with systemic methotrexate, 48.9% underwent dilation and evacuation (D&E), and 15.6% were treated with laprotomy. This distribution highlights the varied approaches in managing cesarean scar pregnancies, with D&C being the most commonly employed method among the study patients

Among those who received medical treatment, 31.3% experienced successful outcomes, while 68.8% did not. In contrast, surgical treatment had a significantly higher success rate, with 93.1% of patients experiencing successful outcomes, compared to 6.9% who did not. The p-value of <0.001 indicates that the difference in success rates between medical and surgical treatments is statistically significant. This data underscores the higher efficacy of surgical interventions over medical treatments for managing cesarean scar pregnancies.

For medical treatment, 6 patients (37.5%) experienced the persistence of scar pregnancy, 3 patients (18.8%) had vaginal bleeding, and 2 patients (12.5%) reported pain. Overall, complications were observed in 11 patients (68.8%) undergoing medical treatment. In contrast, for surgical treatment, only 2 patients (6.9%) experienced the persistence of scar pregnancy, and no cases of vaginal bleeding or pain were reported. The overall complication rate for surgical treatment was 2 patients (6.9%). The P-value for the persistence of scar pregnancy is <0.001, indicating a statistically significant difference between the two treatment methods, with surgical treatment showing a significantly lower complication rate compared to medical treatment.

              Statistically Significant Difference (P-value<0.05); CI: Confidence Interval

Patients receiving medical treatment had a mean hospital stay of 8.7 days with a standard deviation (SD) of 3.41 days, and a 95% confidence interval (CI) for the mean ranging from 7.3 to 9.8 days. In contrast, patients undergoing surgical treatment had a significantly shorter mean hospital stay of 4.2 days with an SD of 2.19 days, and a 95% CI for the mean from 3.6 to 5.2 days. The p-value of <0.001 indicates that this difference is statistically significant. This suggests that surgical treatment not only yields higher success rates and lower complication rates but also results in shorter hospital stays compared to medical treatment.

The first case of cesarean scar pregnancy was reported in 1978, and since then, there has been a significant increase in reported cases.^2,13,14 This rise is likely due to the increasing rate of cesarean deliveries and improvements in early diagnostic techniques. Although the exact cause of cesarean scar pregnancy remains unknown, it is believed to be associated with a pre-existing scar defect or a microscopic dehiscent tract between the cesarean scar and the endometrial canal. Given the absence of a definitive protocol for treating cesarean scar pregnancies (CSP), this study aimed to evaluate the success and complications associated with medical and surgical treatment modalities.

In the present study, the mean age of patients was 32.8 (4.57) years, this aligns with existing literature on the demographic characteristics of patients with cesarean scar pregnancy. Studies have consistently reported that women in their thirties are more commonly affected, reflecting the age group most likely to have undergone cesarean sections due to various obstetric reasons. Studies such as those by Gul B et al. (2021), Verberkt C et al (2023) and Karahasanoglu A et al., (2018) have similarly reported mean ages in this range, reinforcing the demographic profile observed in this study.^15-17 For instance; Karahasanoglu A et al., (2018) reported that the mean maternal age was 32.5 years, range, 24-39 years, which is compatible with our study.¹⁷ The distribution of previous lower segment cesarean sections (LSCS) among the study population indicated a notable history of multiple cesarean deliveries. Specifically, 40.0% of patients had undergone one prior LSCS, 48.9% had experienced two previous LSCS, and 11.1% had undergone three prior LSCS. This trend highlights a significant incidence of repeat cesarean deliveries among patients with cesarean scar pregnancies. Literature supports the association between multiple previous cesarean deliveries and an increased risk of cesarean scar pregnancies. Studies have shown that each additional cesarean delivery increases the likelihood of scar defects or abnormalities, which may contribute to the occurrence of cesarean scar pregnancies.^18-21This finding underscores the importance of careful management and monitoring of patients with multiple cesarean scars to mitigate the risk of complications such as cesarean scar pregnancies. Among the study participants with cesarean scar pregnancies (CSP), 33.3% were Gravida 2, 46.7% were Gravida 3, and 20.0% were Gravida 4 or higher. This distribution reflects the increased risk associated with multiple pregnancies, particularly after cesarean sections. This aligns with existing literature identifying gravidity, parity, and induced abortions as independent risk factors for CSP.^22,23 Research by Luo et al. found that women with CSP exhibited higher gravidity and a greater frequency of induced abortions compared to controls, though not statistically significant in multivariate logistic regression analysis (Luo et al., 2012).²³ These findings highlight the importance of obstetric history in assessing the risk profile for CSP, emphasizing the need for vigilant monitoring and management strategies in clinical practice. Among the patients with cesarean scar pregnancies in this study, a small proportion had a history of previous ectopic pregnancies. Specifically, 4.4% of these patients had experienced tubal pregnancies, and 2.2% had a prior cesarean scar pregnancy. The majority, comprising 93.3% of the study population, had no previous history of ectopic pregnancies.  These findings underscore the relatively low incidence of prior ectopic pregnancies among CSP patients, aligning with literature emphasizing the rarity of previous ectopic events as a risk factor for CSP.^15,24

The high risk of mortality and severe complications sparks intense debate regarding management strategies for cesarean scar pregnancies (CSP). However, there is currently no internationally recognized diagnosis and treatment protocol published. The distribution of treatment modalities in this study reflects the diverse approaches to managing cesarean scar pregnancies (CSP). Systemic methotrexate was used in 35.6% of cases, dilation and curettage (D&C) in 48.9%, and laparotomy in 15.6%. This variability underscores the absence of a standardized protocol for CSP management, aligning with literature that discusses the lack of consensus on optimal treatment strategies (Jurkovic et al., 2009; Kumar et al., 2020 and Zhou W et al., 2022).^14,25,26 The predominance of D&C as the most frequently employed method in this cohort suggests its widespread use despite ongoing debate over its efficacy and safety in treating CSP (Matsushita T et al.,2017 and Fu P et al., 2024).^27,28 The data revealed a stark contrast in treatment outcomes between medical and surgical interventions for cesarean scar pregnancies (CSP). Medical treatment showed a success rate of 31.3%, significantly lower compared to surgical treatment, which achieved a success rate of 93.1%. This substantial difference was statistically significant (p < 0.001), highlighting the superior efficacy of surgical approaches in managing CSP. These findings underscore the emerging consensus in the literature that medical therapies such as methotrexate (MTX) may exhibit limited success rates in the management of cesarean scar pregnancies (CSP), often necessitating subsequent surgical intervention. MTX, although commonly used, often requires additional surgical intervention due to its lower success rates and higher risk of complications compared to surgical methods such as dilation and curettage (D&C) or laparotomy. Supporting our findings, Liny Y et al. (2021) and studies like those by Harb H et al. (2018) from the UK have also demonstrated high success rates associated with surgical interventions in treating CSP.^29,30 Specifically, Harb H et al.(2018) reported a success rate of 96% with surgical management, consistent with our study's outcomes.³⁰ Similarly, Qu W et al. (2022) found that curettage combined with hysteroscopy yielded the highest success rate (95.9%), followed by MTX (85.8%) and ultrasound-guided curettage (84.0%), aligning closely with our findings.⁹ Şimşek et al. (2021) reported a surgical success rate of 96.6% and a medical treatment success rate of 33% (p<0.001), findings that are consistent with our study.³¹ Conversely, studies such as those by Timor-Trisch et al. (2012) have highlighted the effectiveness and safety of local MTX as a viable treatment option, suggesting it as a first-line approach in some cases.³² Additionally, conservative management approaches have been advocated in certain studies for their potential to avoid more invasive surgical procedures, albeit with longer times to achieve negative beta-hCG levels.^33,34 These diverse findings underscore the complexity in choosing the optimal treatment strategy for CSP, balancing efficacy, safety, and patient-specific factors.

In our study, patients who did not respond to medical management were effectively managed with dilation and evacuation (D&E). Among those who initially received medical treatment had a higher complication rate overall (68.8%) compared to surgical treatment (6.9%). Specifically, the persistence of scar pregnancy was significantly more common in the medical treatment group (37.5%) than in the surgical group (6.9%), with a P-value of <0.001, indicating statistical significance. Vaginal bleeding and pain were reported only in the medical treatment group (18.8% and 12.5%, respectively), while no such complications were observed in the surgical group. Among the patients who experienced complications from D&E, only two required laparotomy as a second-line treatment option. The p-value of <0.001 indicated a statistically significant difference in complication rates between the two treatment modalities, with medical management associated with a higher incidence of complications.  These findings are consistent with existing literature highlighting the higher complication rates associated with medical therapies, such as methotrexate, for managing cesarean scar pregnancies (CSP), prompting consideration of surgical interventions like dilation and evacuation (D&E) as more effective and safer alternatives (Şimşek et al., 2021; Birch et al., 2016).^31,35 Şimşek et al. (2021) reported a significantly higher complication rate with medical approaches compared to surgical methods (66% vs. 3.3%, respectively; p<0.001), aligning with the outcomes of our study.³⁵ Additionally, the efficacy and safety of surgical approaches in achieving successful outcomes while minimizing complications have been underscored by several researchers (Harb et al., 2018; Maymon et al., 2004; Agten et al., 2024).30,36  Agten et al. (2024) specifically noted the substantial risk of failure and higher complication rates associated with systemic methotrexate, advocating against its use as a first-line treatment, a perspective consistent with our study findings.³⁷

In the present study, patients receiving medical treatment had a mean hospital stay of 8.7 days with a standard deviation (SD) of 3.41 days. In contrast, patients undergoing surgical treatment had a significantly shorter mean hospital stay of 4.2 days with an SD of 2.19 days. The p-value of <0.001 indicates that this difference is statistically significant. These findings suggest that surgical treatment not only yields higher success rates and lower complication rates but also results in shorter hospital stays compared to medical treatment. The extended hospital time in the methotrexate (MTX) group is attributed to the need for doctors to observe patients between MTX treatment and subsequent surgery.  These results align with those reported by Qu et al. (2022) and Liu et al. (2016), who similarly found that the MTX pretreatment group had a longer duration of hospitalization compared to the surgically managed group.^9,12 Specifically, Qu et al. (2022) demonstrated that the curettage group had the shortest hospital stay, lowest expenses, and a relatively greater reduction in β-hCG levels, which is consistent with our study.¹²

The present study demonstrated that surgical treatments for cesarean scar pregnancies (CSP) yield superior outcomes compared to medical therapies. This conclusion is supported by higher success rates, lower complication rates, and shorter hospital stays observed in patients undergoing surgical interventions. Despite these promising findings, further studies with larger sample sizes and extended follow-up periods are necessary to validate these results and refine treatment protocols. Additionally, comprehensive studies focusing on various surgical techniques and their comparative effectiveness are essential to establish standardized guidelines for the optimal management of CSP. This ongoing research will contribute to improved clinical practice and better patient outcomes in the treatment of CSP.

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