Cesarean scar pregnancy (CSP) is among the most severe iatrogenic complications of cesarean delivery (CD) and is associated with a high risk of severe hemorrhage, uterine rupture, and progression towards placenta accreta spectrum disorders. Prenatal diagnosis of CSP has been recently standardized through a modified Delphi consensus, which also allows risk stratification according of this anomaly. However, several issues on the management of CSP are still under debate. The aim of the present review is to provide an up-to-date on the diagnosis and management of CSP.

Placenta accreta spectrum (PAS) disorders present a significant clinical challenge, characterized by abnormal placental adherence to the uterine wall secondary to uterine scarring. With the rising global cesarean delivery rates, the incidence of this iatrogenic disorder has increased, underscoring the critical need for an understanding of its pathophysiology to inform management and prevention strategies. Normal placentation depends on tightly regulated extravillous trophoblast invasion into the decidua, spiral artery remodeling, interactions with the extracellular matrix, and immune modulation. Uterine scarring disrupts this balance, creating an environment deficient in key regulatory signals required for coordinated implantation and decidualization. In PAS, the loss of inhibitory decidual cues and deficient boundary limits permits unrestrained trophoblast into the abnormal decidual environment. Dysregulated signaling, along with an inflammatory milieu in scarred tissues, exacerbates abnormal placental development. Current prenatal imaging focuses on the appearance of excessive fibrinoid deposition, extracellular matrix remodeling, and incomplete spiral artery transformation as surrogates of PAS risk stratification. Emerging single-cell RNA sequencing and proteomic profiling offer insights into biomarkers and pathways that enable targeted interventions. Preventive efforts should prioritize reducing cesarean delivery rates to limit uterine scarring. Advances in regenerative medicine and bioengineering, including extracellular matrix-modulating biomaterials, growth factor therapies, and antifibrotic interventions, hold promise for improving scar healing and reducing PAS risk. This review bridges foundational science and clinical application, emphasizing the importance of the underlying placental biology and pathophysiology to make a clinical difference in detecting, treating, and preventing PAS. Addressing drivers of abnormal placentation is critical for improving maternal and neonatal outcomes with this increasingly prevalent iatrogenic condition.

To explore the impact of two surgical methods, ultrasound-guided vacuum aspiration and laparoscopic scar resection with repair on the reproductive outcomes of patients with caesarean scar pregnancy. We systematically selected 562 women who had undergone surgical treatment for caesarean scar pregnancies at a tertiary hospital in China between May 2017 and July 2022. After 6 years of follow-up, the reproductive outcomes of 100 women who desired future pregnancies were ultimately tracked. We retrospectively analysed the clinical data and follow-up records of these women to explore the impact of the two surgical methods on their reproductive outcomes. Among those 100 patients, 43(43%) live births, 19(19%) miscarriages, 15(15%) RCSP, and 38 (38%) cases of secondary infertility. Comparison of the clinical data between the ultrasound-guided vacuum aspiration and laparoscopic scar resection with repair groups showed that patients in the latter had longer hospital stays, higher gestational age at treatment, greater maximum GS diameter, and lower BMI (P < 0.05). Women with thicker myometrial layers at the caesarean scar site were more likely to have live births in subsequent pregnancies (P = 0.044; HR 1.207; 95% CI 1.001-1.909). Older women were at higher risk of miscarriage and recurrent caesarean scar pregnancies (P = 0.028; HR 1.868; 95% CI 1.765-1.985).The reproductive outcomes of women with caesarean scar pregnancies after surgical treatment are optimistic.The reproductive outcomes were not dependent on the type of surgical methods used, either ultrasound-guided vacuum aspiration or laparoscopic scar resection with repair for the treatment of caesarean scar pregnancy. Advancing maternal age in subsequent pregnancies is a risk factor for adverse reproductive outcomes and warrants attention.

This study aimed to analyze the outcome of postoperative re-pregnancies in patients with a cesarean scar pregnancy (CSP) and investigate the factors influencing the occurrence of recurrent cesarean section scar pregnancy (RCSP).

A retrospective analysis was performed on the clinical data of 105 patients with CSP who had undergone surgical treatment and were admitted to the Minda Hospital affiliated with Hubei University for Nationalities, Henan Provincial People's Hospital, Linyi People's Hospital, and Weifang People's Hospital from January 2015 to May 2021. The reproductive outcomes of these patients were monitored, and the factors influencing the occurrence of RCSP were analyzed.

In this study, it was found that the reproductive outcomes of patients with CSP after surgery included ectopic pregnancy, normal intrauterine pregnancy, RCSP, and abortion. The postoperative re-pregnancy rate was 51.72% (105/203), and the postoperative RCSP rate was 13.33% (14/105). The number of cesarean sections (OR = 2.004, 95% CI: 1.412-22.579, p < 0.001) was identified as an independent risk factor for the occurrence of RCSP, and the intraoperative removal of the uterine scar (OR = 0.045, 95% CI: 0.005-190.400, p = 0.002) was determined as an independent protective factor for the occurrence of RCSP.

For patients with residual reproductive requirements after CSP surgery, the removal of uterine scar tissue during the operation can be contemplated. Subsequent postoperative re-pregnancy demands close surveillance and follow-up during gestation, with appropriate termination of pregnancy when warranted. For patients without reproductive needs after surgery, contraception is recommended to prevent the occurrence of RCSP.

Given the limitations in perioperative management strategies available at freestanding abortion clinics, abortion providers must commonly discern which patients are too complicated for procedural abortions at their center and must be referred for a hospital-based abortion. The need to transition from freestanding clinics to hospital-based abortion care can lead to delays in completing an abortion and significant social, economic, and psychological repercussions for the pregnant individual. One significant clinical problem that exemplifies the issue of who can be safely taken care of at a freestanding abortion clinic is when the placenta accreta spectrum is suspected. Placenta accreta spectrum is one of the major contributors to maternal morbidity and mortality in the United States, requiring coordinated multidisciplinary management to ensure the safest outcome for the pregnant individual. In this Clinical Opinion, we review the literature focused on identifying individuals at risk for placenta accreta spectrum >14+0 weeks gestation, delineate an algorithm to improve the frequency of timely referrals to hospital-based abortion providers, and propose next steps for future training goals and research on placenta accreta spectrum in the second trimester between complex family planning and maternal-fetal medicine subspecialists.

Obstetric hemorrhage is a leading cause of maternal morbidity and mortality. An important etiology of obstetric hemorrhage is placenta accreta spectrum. In the last 2 decades, there has been increased clinical experience of the devastating effect of undiagnosed, as well as late diagnosed, cases of cesarean scar pregnancy. There is a growing body of evidence suggesting that cesarean scar pregnancy is an early precursor of second- and third-trimester placenta accreta spectrum. As such, cesarean scar pregnancy should be diagnosed in the early first trimester. This early diagnosis could be achieved by introducing regimented sonographic screening in pregnancies of patients with previous cesarean delivery. This opinion article evaluates the scientific and clinical basis of whether cesarean scar pregnancy, with special focus on its early first-trimester discovery, complies with the accepted requirements of a screening test. Each of the 10 classical screening criteria of Wilson and Jungner were systematically applied to evaluate if the criteria were met by cesarean scar pregnancy, to analyze if it is possible and realistic to carry out screening in a population-wide fashion.

The aim of this study was to assess the influence of the cesarean section scars on the mean pulsatility index (PI) of the uterine artery Doppler between 20 and 34 weeks of gestation. A secondary objective was to assess the association between previous cesarean section and adverse maternal/perinatal outcomes.

A retrospective cohort study was conducted with pregnant women who had their deliveries between March 2014 and February 2023. PI of the uterine arteries Doppler was performed transvaginally between 20-24 weeks and transabdominally between 28-34 weeks. The following variables were considered adverse perinatal outcomes: birth weight < 10th percentile for gestational age, preeclampsia, premature birth, placental abruption, perinatal death, postpartum hemorrhage, neonatal intensive care unit (NICU) admission.

A total of 479 pregnant women were included in the final statistical analysis, being that 70.6% (338/479) had no (Group I) and 29.4% (141/479) had at least one previous cesarean section (Group II). Pregnant women with a previous cesarean had higher median of mean PI (1.06 vs. 0.97, p = 0.044) and median MoM of mean PI uterine arteries Doppler (1.06 vs. 0.98, p = 0.037) than pregnant women without previous cesarean section at ultrasound 20-24 weeks. Pregnant women with a previous cesarean section had higher median of mean PI (0.77 vs. 0.70, p < 0.001) and mean MoM PI uterine arteries Doppler (1.08 vs. 0.99, p < 0.001) than pregnant women without previous cesarean section at ultrasound 28-34 weeks. Pregnant women with ≥ 2 previous cesarean sections had a higher median of mean PI uterine arteries Doppler than those with no previous cesarean sections (1.19 vs. 0.97, p = 0.036). Group II had a lower risk of postpartum hemorrhage (aPR 0.31, 95% CI 0.13-0.75, p = 0.009) and composite neonatal outcome (aPR 0.66, 95% CI 0.49-0.88, p = 0.006). Group II had a higher risk of APGAR score at the 5th minute < 7 (aPR 0.75, 95% CI 1.49-51.29, p = 0.016).

The number of previous cesarean sections had a significant influence on the mean PI uterine arteries Doppler between 20-24 and 28-34 weeks of gestation. Previous cesarean section was an independent predictor of postpartum hemorrhage and APGAR score at the 5th minute < 7. Pregnancy-associated arterial hypertension and number of previous deliveries influenced the risk of composite neonatal outcome, but not the presence of previous cesarean section alone.

To determine whether the new classification system published by Jordans et al for cesarean scar pregnancy (CSP) can guide management and treatment outcomes.

A retrospective study of women diagnosed with CSP from October 2010 to December 2022 in a single tertiary center was performed. Sonographic records of these women were classified into three types according to the classification published by Jordans et al. Treatment outcomes were compared across each type of CSP.

The study included a total of 84 women, where 60 (71.4%), 17 (20.2%), and 7 (8.3%) of them were categorized into Type 1, 2, and 3 CSP, respectively. A total of 47 (55.9%) women were managed with methotrexate, 22 (26.2%) underwent surgical management of the CSP without removal of the Cesarean section (CS) niche, and 11 (13.1%) underwent surgery to remove the CSP and the CS niche. Overall treatment success rates for medical management and surgical management were 70 and 97%, respectively. Four women were managed expectantly and continued their pregnancies, among which three carried beyond 34 weeks and had good neonatal outcomes.

The classification as published by Jordans et al is easily replicable and readily implemented clinically. Our findings show that a higher proportion of Type 1 and Type 2 CSP were treated successfully by a less invasive medical approach with a high success rate, whereas most Type 3 CSP required surgical resection to successfully remove the CSP and the CS niche. Prospective studies are required to confirm these findings and further validate the clinical utility of this nomenclature system.

The nomenclature has evolved from low implantation to cesarean scar pregnancy (CSP) and criteria are recommended for identification and management. Management guidelines include pregnancy termination due to life-threatening complications. This article applies ultrasound (US) parameters recommended by the Society for Maternal Fetal Medicine (SMFM) in women who were expectantly managed.

Pregnancies were identified between March 1, 2013 and December 31, 2020. Inclusion criteria were women with CSP or low implantation identified on US. Studies were reviewed for niche, smallest myometrial thickness (SMT), and location of basalis blinded to clinical data. Clinical outcomes, pregnancy outcome, need for intervention, hysterectomy, transfusion, pathologic findings, and morbidities were obtained by chart review.

Of 101 pregnancies with low implantation, 43 met the SMFM criteria at < 10 weeks and 28 at 10 to 14 weeks. At < 10 weeks, SMFM criteria identified 45out of 76 women; of these 13 required hysterectomy; there were 6 who required hysterectomy but did not meet the SMFM criteria. At 10 to < 14 weeks, SMFM criteria identified 28 out of 42 women; of these 15 required hysterectomy. US parameters yielded significant differences in women requiring hysterectomy, at < 10 weeks and 10 to < 14 weeks' gestational age epochs, but the sensitivity, specificity, positive (PPV), and negative predictive values (NPV) of these US parameters have limitations in identifying invasion to determine management. Of the 101 pregnancies, 46 (46%) failed < 20 weeks, 16 (35%) required medical/surgical management including 6 hysterectomies, and 30 (65%) required no intervention. There were 55 pregnancies (55%) that progressed beyond 20 weeks. Of these, 16 required hysterectomy (29%) while 39 (71%) did not. In the overall cohort of 101, 22 (21.8%) required hysterectomy and an additional16 (15.8%) required some type of intervention, while 66.7% required no intervention.

SMFM US criteria for CSP have limitations for discerning clinical management due to lack of discriminatory threshold.

· The SMFM US criteria for CSP at <10 or <14 weeks have limitations for clinical management.. · The sensitivity and specificity of the ultrasound findings limit the utility for management. · The SMT of <1 mm is more discriminating than <3 mm for hysterectomy..

To evaluate Cesarean scar defects using saline contrast sonohysterography (SCSH) in women with a history of Cesarean scar pregnancy (CSP).

A cohort of 38 non-pregnant women with a history of CSP treated with combined local and systemic methotrexate was investigated prospectively by SCSH. For the purpose of analysis, they were classified, according to the modified Delphi consensus criteria for CSP in early gestation, into three subgroups based on the depth of the gestational sac herniation in the midsagittal plane. Subgroup A included eight (21.1%) cases, in which the largest part of the gestational sac protruded towards the uterine cavity; Subgroup B included 20 (52.6%) cases, in which the largest part of the gestational sac was embedded in the myometrium; and Subgroup C included 10 (26.3%) cases, in which the gestational sac was located partially outside the outer contour of the cervix or uterus.

SCSH revealed that all women in Subgroup C had a uterine niche. The median niche length (P = 0.006) and depth (P = 0.015) were significantly greater in Subgroup C than in Subgroups A or B. The median residual myometrial thickness (RMT) was significantly lower in Subgroup C than in Subgroups A or B (P = 0.006).

Women with prior CSP who had a gestational sac protruding beyond the serosal line had a significantly greater niche length and depth, and lower RMT. This knowledge may guide individualized risk counseling. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

The clinical management of placenta accreta spectrum (PAS) depends on placental topography and vascular involvement. Our aim was to determine whether transabdominal and transvaginal ultrasound signs can predict PAS management.

We conducted a retrospective cohort study of consecutive prenatally suspected PAS cases in a single tertiary-care PAS center between January 2021 and July 2022. When PAS was confirmed during surgery, abdominal and transvaginal ultrasound scans were analyzed in relation to PAS management. The preferred surgical approach of PAS was one-step conservative surgery (OSCS). Massive blood loss and PAS topography in the lower bladder trigone necessitated cesarean hysterectomy. Transvaginal ultrasound-diagnosed intracervical hypervascularity was split into three categories based on their quantity. Anatomically, the internal cervical os is located at the level of the bladder trigone and was used as landmark for upper and lower bladder trigone PAS.

Ninety-one women underwent OSCS and 35 women underwent cesarean hysterectomy (total 126 women with PAS). Abdominal and transvaginal ultrasound features differed significantly between women that underwent OSCS and cesarean hysterectomy: decreased myometrial thickness (<1 mm), 82.4% vs. 100%, p = 0.006; placental bulge, 51.6% vs. 94.3%, p < 0.001; bladder wall interruption, 62.6% vs. 97.1%, p < 0.001; abnormal placental lacunae, 75.8% vs. 100%, p < 0.001; hypervascularity (large lacunae feeding vessels, 57.8% vs. 94.6%, p < 0.001; parametrial hypervascularity, 15.4% vs. 60%, p < 0.001; the rail sign, 6.6% vs. 28.6%, p = 0.003; three-dimensional Doppler intra-placental hypervascularity, 81.3% vs. 100%, p < 0.001; intracervical hypervascularity 60.4% vs. 94.3%, p < 0.001); and cervical length 2.5 ± 0.94 vs. 2.2 ± 0.73, p = 0.038. Other ultrasound signs were not significantly different. The results of multivariable logistic regression showed placental bulge (odds ratio [OR] 9.3; 95% CI 1.9-44.3; p = 0.005), parametrial hypervascularity (OR 4.1; 95% CI 1.541-11.085; p = 0.005), and intracervical hypervascularity (OR 9.2; 95% CI 1.905-44.056; p = 0.006) were weak predictors of OSCS. Intracervical hypervascularity Grade 1 (vascularity <50% of cervical tissue) was more present in OSCS than higher gradings two and three (91% vs. 27.6% vs. 14.3%; p < 0.001).

Cesarean hysterectomy is associated with the PAS signs of placental bulge and Grade 2 and 3 intracervical hypervascularity. OSCS is associated with intracervical hypervascularity Grade 1 on transvaginal ultrasound. Prospective validation is required to formulate predictors for PAS management.

Cesarean scar pregnancy (CSP) is among the most severe complications of cesarean delivery. CSP refers to the abnormal implantation of the gestational sac in the area of the prior cesarean delivery (CD), potentially leading to severe hemorrhage, uterine rupture, or development of placenta accreta spectrum disorders (PAS). The management of women with CSP has not been standardized yet. In women who opted for termination, discussion about the treatments should consider maternal symptoms, gestational age at intervention, and the future reproductive risk. A multitude of treatments, either medical or surgical, for CSP has been reported in the published literature. The present review aims to provide up-to-date information on a recently introduced minimally invasive treatments for CSP, including the single and double balloon catheter. The methodology of using the single or double catheter is described in a step-by-step fashion illustrated by pictures as well as video recordings. Both catheters have their deserved place to be used as a primary method for terminating scar pregnancies as well as using them as adjuncts to other treatments. They were successfully used by multiple individual practitioners and institutions due to their simplicity and low complication rates. The rare, but possible post-procedure complications such as recurrent CSP and enhanced myometrial vascularity are also mentioned.

Recently, a new standardized sonographic evaluation system for cesarean scar pregnancies (CSP) was published. We aimed to evaluate the clinical outcomes of CSP cases according to the new sonographic evaluation and reporting system.

A retrospective study conducted at a single tertiary center. All CSPs between 1/2011 and 4/2022 were included. Cases were evaluated by expert sonographers and classified into three categories: 1) CSP in which the largest part of the gestational sac (GS) protrudes towards the uterine cavity; 2) CSP in which the largest part of the GS is embedded in the myometrium but does not cross the serosal contour; and 3) CSP in which the GS is partially located beyond the outer contour of the cervix or uterus.Baseline characteristics, management and outcomes were compared between the three categories.

Overall, 55 patients were diagnosed with CSP during the study period; 10 (18.1 %) type 1, 31 (56.3 %) type 2, and 14 (25.4 %) type 3. Baseline characteristics were similar among groups. Compared with type 2 and 3, patients diagnosed with CSP type 1 received less methotrexate treatment [83.9 % and 78.6 % vs. 40.0 %, respectively, p = 0.020]. The rates of need for invasive procedures, urgent procedures, major bleeding, length of hospitalization, and subsequent pregnancies were similar between groups.

No clinically significant differences were found between groups divided by the new standardized sonographic evaluation and reporting system for CSP in pregnancy characteristics, management, and subsequent pregnancy outcomes. Further investigation is required to enable informed management of CSP based on the new sonographic reporting system.

Heterotopic cesarean scar pregnancy is an extremely rare form of pregnancy and is defined as an intrauterine pregnancy coexisting with an ectopic pregnancy implanted in the cesarean scar. Cesarean scar ectopic pregnancy can also be a precursor for placenta accreta spectrum, a potentially life-threatening condition in which the placenta is abnormally adherent to the uterine myometrium and possibly adjacent organs. Although cesarean scar ectopic pregnancies are rare, there has been an increase in their incidence due to the rise in cesarean deliveries. We present the case of a 35-year-old patient with a heterotopic pregnancy with ectopic implantation in a cesarean scar and associated placenta increta, as well as the radiologic evaluation of placenta accreta spectrum and subsequent management.

Expectant management is not recommended for cesarean scar pregnancies because they are often associated with placenta accreta, cesarean hysterectomy, and massive life-threatening hemorrhages during delivery. Herein, we report a case of placenta accreta spectrum with ureteral invasion due to the progression of a cesarean scar pregnancy. Case. A 41-year-old woman, with a history of three cesarean sections and two miscarriages, was referred to our hospital at 25 weeks of gestation with a diagnosis of placenta accreta spectrum and bladder invasion. Although the gestational sac was located anterior to the lower uterine segment, a cesarean-scar pregnancy was not diagnosed. A cesarean hysterectomy was performed at 31 weeks of gestation with the placement of an aortic balloon. The placenta was found to adhere to the ureter with more than the expected parenchymal tissue displacement (FIGO Classification 3b). The ureter was not obstructed and was preserved by leaving the placenta slightly on the ureteral side. Postoperatively, a ureteral stent was placed because of the ureteral stricture in the area where the placenta had adhered. Two months after surgery, the ureteral stent was removed after observing an improvement in stenosis. An adherent placenta due to continued cesarean scar pregnancy should be managed by assuming placental invasion beyond the parenchyma into the ureter.

A Cesarean Scar Pregnancy (CSP) is a variant of uterine ectopic pregnancy defined by full or partial implantation of the gestational sac in the scar of a previous cesarean section. The continuous increase of Cesarean Deliveries is causing a parallel increase in CSP and its complications. Considering its high morbidity, the most usual recommendation has been termination of pregnancy in the first trimester; however, several cases progress to viable births. The aim of this systematic review is to evaluate the outcome of CSP managed expectantly and understand whether sonographic signs could correlate to the outcomes. An online-based search of PubMed and Cochrane Library Databases was used to gather studies including women diagnosed with a CSP who were managed expectantly. The description of all cases was analysed by the authors in order to obtain information for each outcome. 47 studies of different types were retrieved, and the gestational outcome was available in 194 patients. Out of these, 39 patients (20,1%) had a miscarriage and 16 (8,3%) suffered foetal death. 50 patients (25,8%) had a term delivery and 81 (41,8%) patients had a preterm birth, out of which 27 (13,9%) delivered before 34 weeks of gestation. In 102 (52,6%) patients, a hysterectomy was performed. Placenta Accreta Spectrum (PAS) was a common disorder among CSP and was linked to a higher rate of complications such as foetal death, preterm birth, hysterectomy, haemorrhagic morbidity and surgical complications. Some of the analysed articles showed that sonographic signs with specific characteristics, such as type II and III CSP classification, Crossover Sign - 1, "In the niche" implantation and lower myometrial thickness could be related to worse outcomes of CSP. This article provides a good understanding of CSP as an entity that, although rare, presents with a high rate of relevant morbidity. It is also understood that pregnancies with confirmed PAS had an even higher rate of morbidity. Some sonographic signs were shown to predict the prognosis of these pregnancies and further investigation is necessary to validate one or more signs so they can be used for a more reliable counselling of women with CSP.

Clinical evaluation of the new Delphi consensus definition of cesarean scar pregnancy (CSP) in early gestation.

A retrospective cohort of 36 women diagnosed with CSP and treated with combined local and systemic methotrexate (MTX) between 2008 and 2021. The CSPs were classified according to the new Delphi consensus criteria into three subgroups based on the depth of the gestational sac herniation in the sagittal plane. Subgroup A included 8 (22.2%) cases in which the largest part of the gestational sac protruded toward the uterine cavity. Subgroup B included 22 (61.1%) cases in which the largest part of the gestational sac was embedded in the myometrium, and subgroup C included 6 (16.7%) cases in which the gestational was partially located outside the outer contour of the cervix or uterus.

The β-HCG level upon admission was significantly lower in subgroup A than in subgroups B or C (11,075 ± 7109, 18,787 ± 16,585, and 58,273 ± 55,267 mIU/mL, respectively, P = .01). All subgroup C patients had repeated courses of MTX and surgical interventions (laparotomy, uterine artery embolization, and operative hysteroscopy) at double the rate of subgroups A or B (100, 50, and 40.9%, respectively, P = .036). The duration of hospitalization was significantly shorter in subgroup A than in subgroups B or C (1.9 ± 1.5, 2.1 ± 1.1, and 5.4 ± 4.9 days, P = .01).

The outcome according to Delphi consensus criteria for defining CSP in early gestation has implications for clinical decision-making, patient care, and the follow-up of CSP.

Screening for clinically significant placenta accreta spectrum (PAS) is possible with a high degree of accuracy (both sensitivity and specificity >90-95%). The group of women to focus on are those with placenta previa and one or more prior Cesarean deliveries. Screening for PAS not associated with placenta previa is not as productive, and several false negatives have been described. The results of the screening program indicate that women have a low or high probability of PAS. Screen-positive women or those with uncertain ultrasound features should be referred to a center of excellence. Those confirmed to have a high probability of PAS should electively be delivered at such centers.

To describe treatment and outcomes of patients with confirmed cesarean scar ectopic pregnancy (CSEP) at a tertiary referral center.

We reviewed a deidentified family planning clinical database for patients seen by our subspecialty service for CSEP from January 2017 through December 2021 in this case series. We extracted referral information, final diagnosis, management, and outcome measures including estimated blood loss, secondary procedures, and treatment complications.

Of 57 cases referred for suspected CSEPs, 23 (40%) had confirmed diagnoses; one additional case was diagnosed during clinic evaluation for early pregnancy loss. Most (n = 50 [88%]) referrals occurred in the last 2 years of the 5-year study period. Of 24 confirmed CSEP cases, eight were pregnancy losses at the time of diagnosis. Fourteen cases were ≤50 days gestation or gestational size (7 [50%] pregnancy losses) and 10 >50 days gestation (range 39-66 days). We treated all 14 patients ≤50 days primarily with suction aspiration under ultrasound guidance in an operating room with no complications and estimated blood loss of 14 ± 10 mL. Of the 10 patients>50 days (maximum 66 days), seven were managed with primary aspiration of which five were uncomplicated. We treated one patient (57 days) had primary intrauterine double-catheter balloon with immediate hemorrhage requiring uterine artery embolization followed by an uncomplicated suction aspiration.

Patients with confirmed CSEPs at 50 days or less gestation or gestational size can likely be primarily treated with suction aspiration with low risk for significant adverse outcomes. Treatment success and complications are directly related to gestational age at treatment.

Ultrasound-guided suction aspiration monotherapy should be considered for primary CSEP treatment up to 50 days and, with continued experience, may be reasonable beyond 50 days gestation. Invasive treatments or those that require multiple days and visits, such as methotrexate or balloon catheters, are not necessary for early CSEPs.

The incidence of Cesarean scar pregnancies (CSPs) is rising globally. Ultrasound criteria for the diagnosis of CSPs have been described by the International Society of Ultrasound in obstetrics and gynecology and appear to be well used in various centers around the world. There is no guidance on best practices for expectant management of CSP, and there is considerable variation in how this is offered globally. Many studies have reported significant maternal morbidity in cases of CSP with fetal cardiac activity managed expectantly, largely relating to hemorrhage and cesarean hysterectomy from placenta accreta spectrum. However, high live birth rates are also reported. Literature describing the diagnosis and expectant management of CSP in low-resource settings is lacking. Expectant management in selected cases where no fetal cardiac activity is present is a reasonable option and can be associated with good maternal outcomes. Standardization in reporting different types of CSPs and correlating these with pregnancy outcomes will be an important next step in developing guidance for expectant management of this high-risk pregnancy with a high burden of complications.

The incidence of cesarean scar pregnancy (CSP) is increasing reflecting the global increase in cesarean section (CS) rate which has almost doubled since 2000. CSP differs from other types of ectopic pregnancy in its ability to progress while still carrying a significant risk of maternal morbidity. Little is known about precise etiology or natural history although current interest in the pathology of placenta accretes spectrum disorders might be enlightening. Early detection and treatment of CSP are challenging. Once diagnosed, the recommendation is to offer early termination of pregnancy because of the potential risks of continuing the pregnancy. However, as the likelihood of future pregnancy complications for any CSP varies depending on its individual characteristics, this might not always be necessary nor might it be the patient's preferred choice if she is asymptomatic, hemodynamically stable, and wants a baby. The literature supports an interventional rather than a medical approach but the safest and most efficient clinical approach to CSP in terms of treatment modality and service delivery has yet to be determined. This review aims to provide an overview of CSP etiology, natural history, and clinical implications. Treatment options and methods of CSP repair are discussed. We describe our experience in a large tertiary center in Singapore with around 16 cases/year where most treatment modalities are available as well as an "accreta service" for continuing pregnancies. We present a simple algorithm for approach to management including a method of triaging for those CSPs suitable for minimally invasive surgery.

This review aims at summarizing the latest evidence on diagnosis, natural history and management of caesarean scar pregnancy (CSP).

CSP can result in maternal morbidity from major haemorrhage, uterine rupture, placenta accreta spectrum disorders and hysterectomy. Classification of the CSP types, presence of fetal heart activity, gestational age and residual myometrial thickness seem to influence rates of ongoing pregnancy, subsequent development of placenta accreta with expectant management, as well as success and complication rates associated with various methods of pregnancy termination. Expectant management may be appropriate in certain good prognosis cases, such as absent fetal heart activity or when the myometrial layer at the implantation site is relatively thick. Surgical treatments are typically associated with higher success rates, but seem to result in severe haemorrhage more frequently than medical treatments, which have higher failure rates. Although other treatment modalities are available, in general, the size and quality of evidence to guide care provision in CSP is very poor.

CSP can be associated with severe maternal morbidity but can also lead to a livebirth. There is currently a lack of good-quality evidence to predict the outcome of CSP and provide informed and evidence-based care.

Cesarean scar ectopic pregnancy is a complication in which an early pregnancy implants in the scar from a previous cesarean delivery. This condition presents a substantial risk for severe maternal morbidity and mortality because of challenges in securing a prompt diagnosis. Ultrasound is the primary imaging modality for cesarean scar ectopic pregnancy diagnosis, although a correct and timely determination can be difficult. Surgical, medical, and minimally invasive therapies have been described for cesarean scar ectopic pregnancy management, but the optimal treatment is unknown. Patients who decline treatment of a cesarean scar ectopic pregnancy should be counseled regarding the risk for severe morbidity. The following are the Society for Maternal-Fetal Medicine recommendations: we recommend against expectant management of cesarean scar ectopic pregnancy (GRADE 1B); we suggest that operative resection (with transvaginal or laparoscopic approaches when possible) or ultrasound-guided uterine aspiration be considered for the surgical management of cesarean scar ectopic pregnancy and that sharp curettage alone be avoided (GRADE 2C); we suggest intragestational methotrexate for the medical treatment of cesarean scar ectopic pregnancy, with or without other treatment modalities (GRADE 2C); we recommend that systemic methotrexate alone not be used to treat cesarean scar ectopic pregnancy (GRADE 1C); in patients who choose expectant management and continuation of a cesarean scar ectopic pregnancy, we recommend repeated cesarean delivery between 34 0/7 and 35 6/7 weeks of gestation (GRADE 1C); we recommend that patients with a cesarean scar ectopic pregnancy be advised on the risks of another pregnancy and counseled regarding effective contraceptive methods, including long-acting reversible contraception and permanent contraception (GRADE 1C).

The aim of this study was to review the reproductive outcomes of women with a cesarean scar pregnancy (CSP) treated with dilation and curettage (D&C) after uterine artery embolization (UAE).

This was a retrospective study to review women who received UAE followed by D&C for CSP between January 2010 and December 2019 at the Changhua Christian Hospital, Changhua in Taiwan. Data were collected from both electronic and paper medical records. Patients were contact via phone call to follow up reproductive outcomes between January 2021 and March 2021. These subsequent reproductive outcomes (including pregnancy rate, secondary infertility rate, miscarriage rate, live birth rate, and recurrent CSP rate) were recorded and analyzed.

A total of 53 cases of women who received UAE followed by D&C for CSP were identified. The women's average age was 34.8 ± 5.1 years. The mean gestational age at diagnosis was 6.2 ± 1.1 weeks. The mean level for human chorionic gonadotropin was 23,407.7 ± 29,105.5 mIU/ml. The average of blood loss during D&C was 19.2 ± 43.6 ml. The average hospitalization time after D&C was 3.5 ± 1.1 days. Of the 53 cases, 10 patients were lost to follow-up and 43 patients agreed to follow-up on reproductive outcomes in 2021. Twenty-three patients who desired to conceive were analyzed. Nineteen out of these 23 women (82.6%) succeeded in conceiving again and gave birth to 15 healthy babies (78.9%). Only one woman (1/19, 5.3%) experienced recurrence of CSP. The average time interval between previous CSP treatment and subsequent conception was 10.4 ± 6.7 months.

UAE combined with curettage treatment in CSP patients results in a positive rate of subsequent pregnancy outcomes. This minimally invasive procedure may be considered as one of the treatment options for CSP, as it enables preservation of fertility after treatment.

This study compared the efficacy and safety of a combination of uterine artery embolization or methotrexate before hysteroscopy in the treatment of cesarean scar pregnancy.

We divided 276 cesarean scar pregnancy patients into three groups. Group A underwent direct hysteroscopy; Group B received uterine artery embolization plus hysteroscopy; Group C received the systemic administration of methotrexate prior to hysteroscopy.

The patients in Group A lost significantly more blood than those in Groups B (P < 0.05). There were no significant differences between the three groups with regards to massive hemorrhage and transfusion (P > 0.05). None of the patients required hysterectomy. Group A was also associated with a significantly shorter period of hospitalization, reduced medical costs, and fewer adverse events than either Group B or C (P < 0.05). Moreover, among women of advanced age (≥35y), the levels of serum anti-Mullerian hormone in Group B were significantly lower than those of the baseline group (P<0.05), which were significantly lower than those in Group A after surgery (4.22 ± 2.35 vs 2.78± 1.89 ng/ml, P < 0.05).

Direct hysteroscopy is a reliable treatment option for most early type I cesarean scar pregnancy patients with a gestational sac. A combination of methotrexate and uterine artery embolization before hysteroscopy in these patients has limited remedial effects. uterine artery embolization may reduce ovarian reserve in patients aged ≥35y.

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).

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.

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).

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.

To evaluate the new ultrasound-based signs for the diagnosis of post-cesarean section uterine niche in nonpregnant women.

We investigated prospectively a cohort of 160 consecutive women with one previous term cesarean delivery (CD) between December 2019 and 2020. All women were separated into two subgroups according to different stages of labor at the time of their CD: subgroup A (n = 109; 68.1%) for elective CD and CD performed in latent labor at a cervical dilatation (≤4 cm) and subgroup B (n = 51; 31.9%); for CD performed during the active stage of labor (>4 cm).

Overall, the incidence of a uterine niche was significantly (P < .001) higher in women who had an elective (20/45; 44.4%) compared with those who had an emergent (21/115; 18.3%) CD. Compared with subgroup B, subgroup A presented with a significantly (P = .012) higher incidence of uterine niche located above the vesicovaginal fold and with a significantly (P = .0002) lower proportion of cesarean scar positioned below the vesicovaginal fold. There was a significantly (P < .001) higher proportion of women with a residual myometrial thickness (RMT) > 3 mm in subgroup A than in subgroup B and a significant negative relationship was found between the RMT and the cervical dilatation at CD (r = -0.22; P = .008).

Sonographic cesarean section scar assessment indicates that the type of CD and the stage of labor at which the hysterotomy is performed have an impact on the location of the scar and the scarification process including the niche formation and RMT.

To develop a standardized sonographic evaluation and reporting system for Cesarean scar pregnancy (CSP) in the first trimester, for use by both general gynecology and expert clinics.

A modified Delphi procedure was carried out, in which 28 international experts in obstetric and gynecological ultrasonography were invited to participate. Extensive experience in the use of ultrasound to evaluate Cesarean section (CS) scars in early pregnancy and/or publications concerning CSP or niche evaluation was required to participate. Relevant items for the detection and evaluation of CSP were determined based on the results of a literature search. Consensus was predefined as a level of agreement of at least 70% for each item, and a minimum of three Delphi rounds were planned (two online questionnaires and one group meeting).

Sixteen experts participated in the Delphi study and four Delphi rounds were performed. In total, 58 items were determined to be relevant. We differentiated between basic measurements to be performed in general practice and advanced measurements for expert centers or for research purposes. The panel also formulated advice on indications for referral to an expert clinic. Consensus was reached for all 58 items on the definition, terminology, relevant items for evaluation and reporting of CSP. It was recommended that the first CS scar evaluation to determine the location of the pregnancy should be performed at 6-7 weeks' gestation using transvaginal ultrasound. The use of magnetic resonance imaging was not considered to add value in the diagnosis of CSP. A CSP was defined as a pregnancy with implantation in, or in close contact with, the niche. The experts agreed that a CSP can occur only when a niche is present and not in relation to a healed CS scar. Relevant sonographic items to record included gestational sac (GS) size, vascularity, location in relation to the uterine vessels, thickness of the residual myometrium and location of the pregnancy in relation to the uterine cavity and serosa. According to its location, a CSP can be classified as: (1) CSP in which the largest part of the GS protrudes towards the uterine cavity; (2) CSP in which the largest part of the GS is embedded in the myometrium but does not cross the serosal contour; and (3) CSP in which the GS is partially located beyond the outer contour of the cervix or uterus. The type of CSP may change with advancing gestation. Future studies are needed to validate this reporting system and the value of the different CSP types.

Consensus was achieved among experts regarding the sonographic evaluation and reporting of CSP in the first trimester. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Placenta accreta has been described as a spectrum of abnormal attachment of villous tissue to the uterine wall, ranging from superficial attachment to the inner myometrium without interposing decidua to transmural invasion through the entire uterine wall and beyond. These descriptions have prevailed for more than 50 years and form the basis for the diagnosis and grading of accreta placentation. Accreta placentation is essentially the consequence of uterine remodeling after surgery, primarily after cesarean delivery. Large cesarean scar defects in the lower uterine segment are associated with failure of normal decidualization and loss of the subdecidual myometrium. These changes allow the placental anchoring villi to implant, and extravillous trophoblast cells to migrate, close to the serosal surface of the uterus. These microscopic features are central to the misconception that the accreta placental villous tissue is excessively invasive and have led to much confusion and heterogeneity in clinical data. Progressive recruitment of large arteries in the uterine wall, that is, helicine, arcuate, and/or radial arteries, results in high-velocity maternal blood entering the intervillous space from the first trimester of pregnancy and subsequent formation of placental lacunae. Recently, guided sampling of accreta areas at delivery has enabled accurate correlation of prenatal imaging data with intraoperative features and histopathologic findings. In more than 70% of samples, there were thick fibrinoid depositions between the tip of most anchoring villi and the underlying uterine wall and around all deeply implanted villi. The distortion of the uteroplacental interface by these dense depositions and the loss of the normal plane of separation are the main factors leading to abnormal placental attachment. These data challenged the classical concept that placenta accreta is simply owing to villous tissue sitting atop the superficial myometrium without interposed decidua. Moreover, there is no evidence in accreta placentation that the extravillous trophoblast is abnormally invasive or that villous tissue can cross the uterine serosa into the pelvis. It is the size of the scar defect, the amount of placental tissue developing inside the scar, and the residual myometrial thickness in the scar area that determine the distance between the placental basal plate and the uterine serosa and thus the risk of accreta placentation.

Cesarean scar pregnancies carry a high risk of pregnancy complications including placenta previa with antepartum hemorrhage, placenta accreta spectrum, and uterine rupture.

To evaluate the development of utero-placental circulation in the first half of pregnancy in ongoing cesarean scar pregnancies and compare it with pregnancies implanted in the lower uterine segment above a previous cesarean delivery scar with no evidence of placenta accreta spectrum at delivery STUDY DESIGN: This was a retrospective case-control study conducted in 2 tertiary referral centers. The study group included 27 women who were diagnosed with a live cesarean scar pregnancy in the first trimester of pregnancy and who elected to conservative management. The control group included 27 women diagnosed with an anterior low-lying placenta or placenta previa at 19 to 22 weeks of gestation who had first and early second trimester ultrasound examinations. In both groups, the first ultrasound examination was carried out at 6 to 10 weeks to establish the pregnancy location, viability, and to confirm the gestational age. The utero-placental and intraplacental vasculatures were examined using color Doppler imaging and were described semiquantitatively using a score of 1 to 4. The remaining myometrial thickness was recorded in the study group, whereas the ultrasound features of a previous cesarean delivery scar including the presence of a niche were noted in the controls. Both the cesarean scar pregnancies and the controls had ultrasound examinations at 11 to 14 and 19 to 22 weeks of gestation.

The mean color Doppler imaging vascularity score in the ultrasound examination at 6 to 10 weeks was significantly (P<.001) higher in the cesarean scar pregnancy group than in the controls. High vascularity scores of 3 and 4 were recorded in 20 of 27 (74%) cases of the cesarean scar pregnancy group. There was no vascularity score of 4, and only 3 of 27 (11%) controls had a vascularity score of 3. In 15 of the 27 (55.6%) cesarean scar pregnancies, the residual myometrial thickness was <2 mm. In the ultrasound examination at 11 to 14 weeks, there was no significant difference between the groups in the number of cases with an increased subplacental vascularity. However, 12 cesarean scar pregnancies (44%) presented with 1 or more placental lacunae whereas there was no case with lacunae in the controls. Of the 18 cesarean scar pregnancies that progressed into the third trimester, 10 of them were diagnosed with placenta previa accreta at birth, including 4 creta and 6 increta. In the 19 to 22 weeks ultrasound examination, 8 of the 10 placenta accreta spectrum patients presented with subplacental hypervascularity, out of which 6 showed placental lacunae.

The vascular changes in the utero-placental and intervillous circulations in cesarean scar pregnancies are due to the loss of the normal uterine structure in the scar area and the development of placental tissue in proximity of large diameter arteries of the outer uterine wall. The intensity of these vascular changes, the development of placenta accreta spectrum, and the risk of uterine rupture are probably related to the residual myometrial thickness of the scar defect at the start of pregnancy. A better understanding of the pathophysiology of the utero-placental vascular changes associated with cesarean scar pregnancies should help in identifying those cases that may develop major complications. It will contribute to providing counseling for women about the risks associated with different management strategies.

Early diagnosis of Cesarean scar pregnancies (CSP) remains difficult. This study describes a novel sonographic marker, the FundAl Retroflexion (FAR) angle, that may be used in the first trimester. The objective of the study is to compare the FAR angle between CSP and normal pregnancies.

For this case-control study, we reviewed images from our institution's database that were acquired from January 2016 to December 2019. All cases of CSP and randomly selected controls, defined as patients with history of Cesarean delivery and normal implantation, that underwent ultrasound evaluation at <14 weeks were included. The FAR angle, defined as the acute angle created between the endometrial echo and cervical canal, was measured. The mean FAR angle was then compared between the two groups and a receiver operating characteristic (ROC) curve was generated.

We identified 15 cases of CSP during the study period and were able to measure the FAR angle in 14 of the cases. The mean FAR angle was larger in CSP than in normal control pregnancies (45° versus 27°, respectively, P < 0.001). Using an ROC curve, a FAR angle cut off of 40° maximizes the ability to distinguish between CSP from normal pregnancies.

The FAR angle provides an easily obtainable and numerical measurement. CSP have larger FAR angle compared to normal controls with a distinguishing cut off of 40°. Larger studies are needed to determine if using the FAR angle can improve first trimester diagnosis for CSP.

Ultrasound (US) prediction of placenta accreta spectrum (PAS) in the first trimester may be aided by postprocessing mechanisms employing color pixel quantification near the bladder-uterine serosal interface. Our objective was to create a postprocessing algorithm of color images to identify findings associated with PAS and compare quantification to sonologist impression in prospectively obtained cine US images.

Transverse transvaginal (TV) US color cines obtained in the first trimester as part of a prospective study were reviewed. Investigators blinded to clinical outcomes reviewed anonymized cines that were archived and labeled the bladder-uterine serosal interface. Color pixels within 2 cm of the defined bladder-uterine serosal interface were ascertained using a Python-based plugin in the Horos open-source DICOM viewer. A sonologist classified the findings as suspicious for invasion, indeterminate, or normal. Statistical analysis was performed using Wilcoxon rank-sum test, Cochran-Armitage trend test, and calculation of receiver-operating characteristic (ROC) curves.

Fifty-four studies met inclusion criteria. Of those, six (11%) required hysterectomy with pathologic confirmation of PAS. Women requiring hysterectomy had a significantly higher color Doppler pixel area than those not requiring hysterectomy (P = .0205). A significant trend was identified in the sonologist impression of invasion (P = .0003). ROC's comparing sonologist impression to Doppler color imaging areas were comparable (P = .054).

Color Doppler mapping in the first trimester showed an increase in color pixel area near the bladder-uterine serosal interface in women requiring cesarean hysterectomy with histologically confirmed PAS at time of delivery, compared to women without hysterectomy or pathologic evidence of PAS.

The study aimed to investigate the potential risk factors for the placenta accreta spectrum (PAS), determine the predictive value of a diagnostic model, and evaluate the effects of octamethylcyclotetrasiloxane (OMCTS) on trophoblast proliferation and migration.

This case-control study included 244 pregnant women with PAS and 327 normal pregnant women who visited Guangzhou Women and Children's Medical Centre, China, from January 2014 to December 2017. Blood was collected from 42 women with PAS and 77 controls, and plasma specimens were analyzed by gas chromatography-time-of-flight mass spectrometry. In addition, the proliferation and migration of trophoblast cells were examined after treatment with OMCTS.

We found an association between the risk of PAS and clinical factors related to fasting blood glucose levels (BS0, OR = 5.78), as well as factors related to endometrial injury [history of cesarean section (OR = 179.59), uterine scarring (OR = 68.37), and history of abortion (OR = 5.66)]. Equally important, pregnant women with PAS had significantly higher plasma OMCTS concentrations than controls. In vitro, we found that OMCTS could promote the proliferation and migration of HTR8/SVneo cells. The model of combining clinical factors and OMCTS had a good performance in PAS prediction (AUC = 0.97, 95% CI 0.78-0.93).

The early diagnosis of PAS in pregnant women requires assessing risk factors, metabolic status, and BS0 levels before 20 weeks of gestation. OMCTS may be related to the development of PAS by promoting trophoblast cell proliferation and migration.

With an increased cesarean delivery rate, the incidence of abnormal placentation is steadily rising, and it is estimated to be around 1.7 per 1000 pregnancies for cesarean scar pregnancy and 1 per 500 pregnancies for placenta accreta spectrum disorder. Current evidence considers cesarean scar pregnancy and placenta accreta spectrum as being the same condition, with different aspects, of the same spectrum, having higher risks with advancing gestation. We present 7 cases, diagnosed and managed in our hospital, at different gestational ages. Early diagnosis is essential for appropriate counseling and subsequent management, and an ultrasound examination is the reference standard for diagnosis. Screening for an abnormally implanted placenta in the first trimester of pregnancy might improve the perinatal outcome and reduce maternal morbidity and mortality.

To review the current literature on the diagnosis and management of cesarean scar pregnancies RECENT FINDINGS: The incidence of cesarean scar pregnancies (CSPs) is increasing as a result of the increasing cesarean section rate, improved diagnostic capabilities, and a growing awareness. CSPs are associated with significant morbidity and early diagnosis is key. Diagnosis is best achieved with transvaginal ultrasound. Sonographic diagnostic criteria have been developed over decades and recently endorsed by the Society for Maternal-Fetal Medicine and other professional societies. The current categorization system differentiates CSPs that are endogenic or 'on the scar' from those that are exogenic or 'in the niche'. Following diagnosis, the challenge remains in determining the optimal management as multiple modalities can be considered. Studies have demonstrated the favorable outcomes with combined local and systemic methotrexate, surgical excision through multiple routes, and adjunctive therapies, such as uterine artery embolization or uterine balloons. The current evidence is insufficient to identify a single best treatment course and a combined approach to treatment is often required.

Successful outcomes while minimizing complications can be achieved with a multidisciplinary, collaborative effort. Guidelines for cesarean scar pregnancies will continue to evolve as the published reports grow.

To evaluate the association between demographic and ultrasound variables and major intra-operative blood loss during surgical transcervical evacuation of live caesarean scar pregnancies.

This was a retrospective cohort study conducted in a tertiary referral center between 2008 and 2019. We included all women diagnosed with a live caesarean scar ectopic pregnancy who chose to have surgical management in the study center. A preoperative ultrasound was performed in each patient. All women underwent transcervical suction curettage under ultrasound guidance. Our primary outcome was the rate of postoperative blood transfusion. The secondary outcomes were estimated intra-operative blood loss (ml), rate of retained products of conception, need for repeat surgery, need for uterine artery embolization and hysterectomy rate. Descriptive statistics were used to describe the variables. Univariate and multivariable logistic regression models were constructed using the relevant covariates to identify the significant predictors for severe blood loss.

During the study period, 80 women were diagnosed with a live caesarean scar pregnancy, of whom 62 (78%) opted for surgical management at our center. The median crown-rump length was 9.3 mm (range 1.4-85.7). Median blood loss at the time of surgery was 100 ml (range, 10-2300), and six women (10%; 95%CI 3.6-20) required blood transfusion. Crown-rump length and presence of placental lacunae were significant predictive factors for the need for blood transfusion and blood loss > 500 ml at univariate analysis (p < .01); on multivariate analysis, only crown-rump length was a significant predictor for need for blood transfusion (OR = 1.072; 95% CI 1.02-1.11). Blood transfusion was required in 6/18 (33%) cases with the crown-rump length ≥ 23 mm (≥9⁺⁰ weeks of gestation), but in none of 44 women presenting with a crown-rump length < 23 mm (p < .01).

The risk of severe intraoperative bleeding and need for blood transfusion during or after surgical evacuation of live caesarean scar pregnancies increases with gestational age and is higher in the presence of placental lacunae. One third of women presenting at ≥ 9 weeks of gestation required blood transfusion and their treatment should be ideally arranged in specialized tertiary centers.

To explore the reproductive outcomes of women with a history of cesarean scar pregnancy (CSP) and the influence of various treatments on subsequent pregnancy outcomes.

The PubMed, Embase, Medline, Cochrane Library and ClinicalTrial.gov databases were searched for studies with the outcomes of pregnancy after CSP treatment. Studies that reported reproductive outcomes after CSP with more than 5 followed cases were included. The main data collected includes the treatment methods of CSP and subsequent pregnancy outcomes. The main information includes intrauterine pregnancy, recurrent CSP (RCSP), and spontaneous miscarriage, while the secondary information includes complications during pregnancies and the outcomes of childbirths. According to different treatments (conservative treatment, surgical treatment without resection of cesarean scar, and surgical treatment with resection of cesarean scar), a stratified analysis was carried out to compare the influence of treatments on subsequent pregnancy outcomes.

A total of 32 studies including 3380 cases of CSP met the inclusion criteria, of which 583 cases conceived again after treatment (including 292 cases of unexpected pregnancy), and finally 178 cases delivered successfully. The follow-up time ranged from 3 to 72 months. Among women with fertility requirements, a total of 291 cases in 403 women were successfully conceived during the follow-up period in 15 studies. Thence the pregnancy rate of women with fertility requirements was 76.2 %. Among all of the 583 successfully conceived women, 83.4 % of them had intrauterine pregnancy, while 15.3 % of cases were RCSP. The total ectopic pregnancy rate reached 16.6 %, covering RCSP and other sites of ectopic pregnancy. 14.6 % of intrauterine pregnancy experienced spontaneous miscarriage. The intrauterine pregnancy rates of the conservative treatment group, the surgical treatment without resection of cesarean scar group, and the surgical treatment with resection of cesarean scar group were 93.1 %, 80.1 % and 86.0 % respectively; the corresponding RCSP rates were 6.9 %, 15.6 % and 14.0 % respectively; and the corresponding spontaneous miscarriage rates were 20.7 %, 13.9 % and 22.2 % respectively.

The outcomes of reproduction after CSP included intrauterine pregnancy, RCSP and other sites of ectopic pregnancy. Women with a history of CSP still have a high pregnancy rate, but the risk of RCSP and spontaneous miscarriage is also increased. It is impossible to clarify the effect of different treatments on subsequent pregnancy. Whether the resection and repair of cesarean scar can ameliorate reproductive outcomes needs to be further assessed. Further large-scale prospective studies, even RCTs with long-term follow-up are needed to expound the outcomes of reproduction after CSP and the effect of different treatments on subsequent reproductive outcomes.

Caesarean scar ectopic pregnancies are the rarest type of ectopic pregnancy. The optimum management regime is not yet established. We report the case of a 39-year-old woman who presented at 11 weeks gestation with painless vaginal bleeding, having had 2 previous caesarean sections. Ultrasound revealed a gestational sac within the caesarean scar niche. On follow-up, her serial ß human chorionic gonadotropin (ßHCG) measurements fell significantly. The woman initially opted for conservative management but subsequently required surgical management. Hysteroscopy demonstrated a sac within the caesarean scar which was successfully evacuated by ultrasound-guided suction curettage, with no complications. Caesarean scar ectopic pregnancies are becoming increasingly common. Diagnosis is primarily through ultrasound using specified criteria. Management may be conservative, medical or surgical excision depending on the clinical circumstances. Hysteroscopy and suction curettage is an effective therapeutic option for caesarean scar ectopic management.

The objective of this study was to evaluate the impact of implantation outside the normal intra-uterine endometrium on development of the gestational sac.

We reviewed and compared the ultrasound measurements and vascularity score around the gestational sac in 69 women diagnosed with a live tubal ectopic pregnancy (TEP) and 54 with a cesarean scar ectopic pregnancy (CSP) at 6-11 weeks of gestation who were certain of their last menstrual period.

The rate of a fetus with a cardiac activity in the study population was significantly (P < 0.001) higher in CSPs than in TEPs. The median maternal age, gravidity and parity were significantly (P =.005; P < 0.001 and P < 0.001, respectively) lower in the TEP than in the CSP group. The number of gestational sac size <5th centile for gestational age was significantly (P < 0.001) higher in the TEP than in the CSP group. There were no differences between the groups for the other ultrasound measurements. In cases matched for gestational age, the gestational sac size was significantly (P < 0.001) smaller in the TEP compared to the CSP group. There was a significant (P < 0.001) difference in the distribution of blood flow score with CSP presenting with higher incidence of moderate and high vascularity than TEP.

Both TEP and CSP are associated with a higher rate of miscarriage than intrauterine pregnancies and the slow development of the gestation sac is more pronounced in TEPs probably as a consequence of a limited access to decidual gland secretions.

To observe the lacunar-like changes in cesarean scar pregnancy (CSP) ultrasonography in first trimester and to explore its relationship with clinical outcome in early pregnancy termination.

This is a retrospective case-control study. Patients who were diagnosed as CSP and chose to terminate pregnancy from January 2017 to April 2020 were enrolled. According to occurrence of lacunar-like change in chorion membrane, patients were divided into case and control group. The clinical manifestation, laboratory test, ultrasound data, and outcome were compared.

Fifty-five CSP patients were enrolled with 20 (36.4%) in case group and 35 (63.6%) in control group. As for ultrasound features, the maximum outer diameter of gestational mass (5.6 ± 2.5 cm vs. 3.9 ± 1.5 cm), the maximum thickness of the chorion membrane (median number 1.1 cm vs. 0.7 cm), the longitudinal diameter of the implanting part of gestational mass in uterine lower segment (3.3 ± 1.8 cm vs. 1.2 ± 0.5 cm), uterine lower segment protrusion incidence (12, 60% vs. 2, 5.7%), and the crown-rump length of fetus (median number 1.7 cm vs. 0.7 cm) were bigger or higher in case group than that of the control group; the minimum thickness of the uterine lower segment myometrium (median number 0.08 cm vs. 0.20 cm) was significantly thinner in case group. CDFI grading of case group was different from control group with more cases in higher grades. As for clinical outcome, the patients of case group showed more frequency of CSP lesion resection under open surgery or laparoscopy (7, 35% vs. 1, 2.86%) rather than suction curettage, more blood loss in surgery (median number 35 ml vs. 20 ml) and more hospitalization days (median number 7.5 d vs. 3.5 d) than control group.

Lacunar-like change of chorion can be detected in early gestation and may act as a predictor of complicated and worse clinical outcome.

The most common anomalies of implantation of the placenta and umbilical cord include placenta previa, placenta accreta spectrum, and vasa previa, and are associated with considerable perinatal and maternal morbidity and mortality. There is moderate quality evidence that prenatal diagnosis of these conditions improves perinatal outcomes and the performance of ultrasound imaging in diagnosing them is considered excellent. The epidemiology of placenta previa is well known, and it is standard clinical practice to assess placental location at the routine screening second-trimester detailed fetal anatomy ultrasound examination. In contrast, the prevalence of placenta accreta spectrum and vasa previa in the general population is more difficult to evaluate because detailed confirmatory histopathologic data are not available in most studies. The sensitivity and specificity of ultrasonography for the diagnosis of these anomalies is also difficult to assess. Recent epidemiologic studies show an increase in the incidence of placental and umbilical cord implantation anomalies, which may be the result of increased use of assisted reproductive technology and cesarean delivery. There is good evidence to support targeted standardized protocols for women at high risk and that screening and diagnosing placenta accreta spectrum and vasa previa should be integrated into obstetric ultrasound training programs.

Placenta Accreta Spectrum (PAS) refers to the range of abnormally adhesive and penetrative placental tissue at a uterine scar. PAS is divided into accreta, increta, and percreta based on degree of myometrial invasion. Its incidence has increased, and PAS is now the leading indication for emergency peripartum hysterectomy in the setting of catastrophic hemorrhage from a non-separating placenta. The recent release of the International Federation of Gynecology and Obstetrics (FIGO) guidelines in 2018 coupled with the joint consensus statement from the Society of Abdominal Radiology (SAR) and European Society of Urogenital Radiology (ESUR) in 2020 reflect decades worth of diagnostic and therapeutic advances in this field. Although the increasing role of MRI in PAS diagnosis is evident, the literature on PAS reveals several disparate but conceptually overlapping MRI signs. Identifying and differentiating between placenta increta and percreta on imaging may be quite challenging even with MRI and sometimes even on final pathology. In this review, we aim to (i) provide a clarified understanding of PAS pathophysiology, (ii) comprehensively review and classify MRI signs based on pathophysiologic underpinnings, (iii) highlight shortcomings in the current PAS literature; and (iv) highlight best practice guidelines for imaging diagnosis of PAS.