Clinical Practice Guidelines and Recommendations by The World Association of Perinatal Medicine and Perinatal Medicine Foundation. Reporting Suspected Findings from Fetal Central Nervous System Examination.

These guidelines follow the mission of the World Association of Perinatal Medicine, in collaboration with the Perinatal Medicine Foundation, which brings together groups and individuals worldwide, with the aim to improve prenatal detection of Central Nervous System anomalies and the appropriate referral of pregnancies with suspected fetal anomalies. In addition, this document provides further guidance for healthcare practitioners with the goal of standardizing the description of ultrasonographic abnormal findings.

The effect of uterine closure technique on cesarean scar niche development after multiple cesarean deliveries.

OBJECTIVES: To use saline infusion sonohysterography (SIS) to evaluate the effect of uterine closure technique on niche formation after multiple cesarean deliveries (CDs). METHODS: Patients with at least one prior CD were evaluated for niche via SIS. Subgroups of any number repeat CD (>1 prior), lower-order CD (<4 prior), and higher-order CD (≥4 prior) were analyzed, stratifying by hysterotomy closure technique at last cesarean preceding imaging; techniques included Technique A (endometrium-free double-layer closure) and Technique B (single- or double-layer routine endo-myometrial closure). Niche defects were quantified (depth, length, width, and residual myometrial thickness). The primary outcome was clinically significant niche, defined as depth >2 mm. Statistical analysis was performed using chi-square, ANOVA, t-test, Kruskal-Wallis, and multiple logistic regression, with p-values of <0.05 were statistically significant. RESULTS: A total of 172 post-cesarean SIS studies were reviewed: 105 after repeat CDs, 131 after lower-order CDs, and 41 after higher-order CDs. Technique A was associated with a shorter interval to imaging and more double-layer closures. Technique B was associated with more clinically significant niches across all subgroups, and these niches were significantly longer and deeper when present. Multiple logistic regression demonstrated a 5.6, 8.1, and 11-fold increased adjusted odds of clinically significant niche following Technique B closure in the repeat CD (p<0.01), lower-order CD (p<0.001), and higher-order CD (p=0.04) groups, respectively. CONCLUSIONS: While multiple CDs are known to increase risk for niche defects and their sequelae, hysterotomy closure technique may help to reduce niche development and severity.

First-trimester cesarean scar pregnancy: a comparative analysis of treatment options from the international registry.

BACKGROUND: A cesarean scar pregnancy is an iatrogenic consequence of a previous cesarean delivery. The gestational sac implants into a niche created by the incision of the previous cesarean delivery, and this carries a substantial risk for major maternal complications. The aim of this study was to report, analyze, and compare the effectiveness and safety of different treatments options for cesarean scar pregnancies managed in the first trimester through a registry. OBJECTIVE: This study aimed to evaluated the ultrasound findings, disease behavior, and management of first-trimester cesarean scar pregnancies. STUDY DESIGN: We created an international registry of cesarean scar pregnancy cases to study the ultrasound findings, disease behavior, and management of cesarean scar pregnancies. The Cesarean Scar Pregnancy Registry collects anonymized ultrasound and clinical data of individual patients with a cesarean scar pregnancy on a secure, digital information platform. Cases were uploaded by 31 participating centers across 19 countries. In this study, we only included live and failing cesarean scar pregnancies (with or without a positive fetal heart beat) that received active treatment (medical or surgical) before 12+6 weeks' gestation to evaluate the effectiveness and safety of the different management options. Patients managed expectantly were not included in this study and will be reported separately. Treatment was classified as successful if it led to a complete resolution of the pregnancy without the need for any additional medical interventions. RESULTS: Between August 29, 2018, and February 28, 2023, we recorded 460 patients with cesarean scar pregnancies (281 live, 179 failing cesarean scar pregnancy) who fulfilled the inclusion criteria and were registered. A total of 270 of 460 (58.7%) patients were managed surgically, 123 of 460 (26.7%) patients underwent medical management, 46 of 460 (10%) patients underwent balloon management, and 21 of 460 (4.6%) patients received other, less frequently used treatment options. Suction evacuation was very effective with a success rate of 202 of 221 (91.5%; 95% confidence interval, 87.8-95.2), whereas systemic methotrexate was least effective with only 38 of 64 (59.4%; 95% confidence interval, 48.4-70.4) patients not requiring additional treatment. Overall, surgical treatment of cesarean scar pregnancies was successful in 236 of 258 (91.5%, 95% confidence interval, 88.4-94.5) patients and complications were observed in 24 of 258 patients (9.3%; 95% confidence interval, 6.6-11.9). CONCLUSION: A cesarean scar pregnancy can be managed effectively in the first trimester of pregnancy in more than 90% of cases with either suction evacuation, balloon treatment, or surgical excision. The effectiveness of all treatment options decreases with advancing gestational age, and cesarean scar pregnancies should be treated as early as possible after confirmation of the diagnosis. Local medical treatment with potassium chloride or methotrexate is less efficient and has higher rates of complications than the other treatment options. Systemic methotrexate has a substantial risk of failing and a higher complication rate and should not be recommended as first-line treatment.

The use of pressure balloons in the treatment of first trimester cesarean scar pregnancy.

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.

Global variation and outcomes of expectant management of CSP.

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.

A new era in teaching: how advanced optical recording technology could change the postcesarean delivery complication conundrum.

BACKGROUND: The last 4 decades have seen increased complications after cesarean deliveries. Despite an incomplete understanding of their etiology, surgical practices have been adopted, creating disproportionate morbidity and the absence of preventive strategies. Additional research tools are needed for further investigation. OBJECTIVE: This study aimed to evaluate the VITOM high-definition optical recording system as a tool to highlight cesarean operative steps and surgical techniques and assess the use of its video recordings for operating room team teaching and research potential. STUDY DESIGN: Contemporaneous cesarean delivery techniques offer no resolution to long-term postcesarean sequelae. From March 2015 to February 2022, a novel tool, VITOM exoscope, was evaluated and used to photograph and video record 104 elective cesarean deliveries. The images were projected on a large screen to be viewed by scrubbed-in and unscrubbed personnel and recorded for future use. During this period, staff participants in 3 designated operating rooms reached 514, including 168 trainee residents, 5 nurse practitioners, 6 physician assistants, 21 medical students, 70 surgical technicians, and 110 circulating nurses. The maternal ages of patients varied from 21 to 49 years. Gestational ages ranged from 28 0/7 to 41 6/7 weeks of gestation. Selected photographs of crucial cesarean surgical steps were taken and printed. Video recordings were stored in designated institutional data storage and uploaded onto a secure drive for further use. After every case, debriefing was held, and subjective opinions were obtained from the various participants. RESULTS: The VITOM was used for 104 cesarean deliveries. Setup time was reduced from 7 minutes initially to 3 minutes with more experience. All staff participants had only positive evaluations and remarks about the image quality and the clear delineation of specific anatomic landmarks. By polling medical students and residents in training, the VITOM experience was described as very useful and, in a few cases, only somewhat useful. The scrubbed surgical technicians and circulating nurses gained a better understanding of surgical layers, improving their ability to anticipate subsequent surgical steps, thereby streamlining operating flow and efficiency. Unscrubbed personnel could also follow the operation's progression despite being remote from the sterile field. Anesthesiologists could follow the operative field and eventual blood loss in plain view. Recorded videos and still photographs were used at clinical teaching conferences and in peer-reviewed publications, enhancing understanding of cesarean delivery techniques. CONCLUSION: The VITOM exoscope provided superb image quality, enabling a clear vision of the anatomic structures of the cesarean operation. It is a promising additional research tool to capture important details of the employed surgical techniques and provides a possible insight into long-term postcesarean sequelae.

Placenta accreta spectrum disorders in the first trimester: a systematic review.

Placenta accreta spectrum (PAS) disorders involve an abnormality in the implantation of the placenta, being rarely diagnosed in the first trimester. To conduct a systematic review of the risk factors, clinical and imaging features, and outcomes of histopathologically confirmed cases of PAS disorders in the first trimester of pregnancy. Different databases including PubMed, MEDLINE Complete, Scopus, Web of Science, EMBASE, SciELO, LILACS, and Ovid were reviewed up to November 2018. 55 patients with a definitive histopathological diagnosis were reported. About 18 had a history of prior curettage and 47 of previous caesarean deliveries (CD). About 74.54% presented with miscarriage and ultrasound signs of caesarean scar pregnancy (CSP) were reported in 22.49%. Temporal sequence of diagnostic studies could be determined in 52 women, and, among these, PAS disorders were defined through imaging techniques in 11 (21.15%) while surgical findings unveiled them in 15 (28.84%). Nonetheless, in half of the cases, the diagnosis was concluded only on histopathological samples. PAS disorders in the first trimester of pregnancy are rarely diagnosed through imaging techniques and lead to hysterectomy in most cases. Ultrasound training to detect PAS disorders in women with risk factors is crucial for early diagnosis and prevention of adverse outcomes.

Methodological Quality of Fetal Brain Structure Charts for Screening Examination and Targeted Neurosonography: A Systematic Review.

INTRODUCTION: Several fetal brain charts have been published in the literature and are commonly used in the daily clinical practice. However, the methodological quality of these charts has not been critically appraised. MATERIAL AND METHODS: MEDLINE, EMBASE, CINAHL, and the Web of Science databases were searched electronically up to December 31, 2020. The primary outcome was to evaluate the methodology of the studies assessing the growth of fetal brain structures throughout gestation. A list of 28 methodological quality criteria divided into three domains according to "study design," "statistical and reporting methods," and "specific relevant neurosonography aspects" was developed in order to assess the methodological appropriateness of the included studies. The overall quality score was defined as the sum of low risk of bias marks, with the range of possible scores being 0-28. This quality assessment was applied to each individual study reporting reference ranges for fetal brain structures. Furthermore, we performed a subgroup analysis according to the different brain structures (ventricular and periventricular, fore-brain and midbrain cerebral and posterior fossa). RESULTS: Sixty studies were included in the systematic review. The overall mean quality score of the studies included in this review was 51.3%. When focusing on each of the assessed domains, the mean quality score was 53.7% for "study design," 54.2% for "statistical and reporting methods," and 38.6% for "specific relevant neurosonography aspects." The sample size calculation, the correlation with a postnatal imaging evaluation, and the whole fetal brain assessment were the items at the highest risk of bias for each domain assessed, respectively. The subgroup analysis according to different anatomical location showed the lowest quality score for ventricular and periventricular structures and the highest for cortical structures. CONCLUSIONS: Most previously published studies reporting fetal brain charts suffer from poor methodology and are at high risk of biases, mostly when focusing on neurosonography issues. Further prospective longitudinal studies aiming at constructing specific growth charts for fetal brain structures should follow rigorous methodology to minimize the risk of biases, guarantee higher levels of reproducibility, and improve the standard of care.

The Impact of Uterine Incision Closure Techniques on Post-cesarean Delivery Niche Formation and Size: Sonohysterographic Examination of Nonpregnant Women.

OBJECTIVE: To compare the prevalence and size of residual niche in the nongravid uterus following Cesarean delivery (CD) with different hysterotomy closure techniques (HCTs). METHODS: Saline infusion sonohysterogram (SIS) was performed in women after one prior CD, documenting the presence or absence of a postoperative niche and measuring its depth, width, length, and residual myometrial thickness. Women were grouped by HCT: Technique A (endometrium-free) and Technique B (routine non-endometrium-free). The primary outcome was the prevalence of a clinically significant niche, defined as a depth of >2 mm. HCT groups were compared using χ2 , T-test (ANOVA), and analyzed using logistic regression and two-sided test (P < .05). RESULTS: Forty-five women had SIS performed, 25 and 20 via Technique A and B, respectively. Technique groups varied by average interval time from CD to SIS (13.6 versus 74.5 months, P = 0.006) but were otherwise similar. Twenty niches were diagnosed, 85% of which were clinically significant, including five following Technique A, nine following Technique B with double-layer closure, and three following Technique B with single-layer (P = .018). The average niche depth was 2.4 mm and 4.9 mm among the two-layer subgroups following Techniques A and B, respectively (P = .005). A clinically significant niche development was six times higher with Technique B when compared to Technique A (OR 6.0, 95% CI 1.6-22.6, P = .008); this significance persisted after controlling for SIS interval on multivariate analysis (OR 4.4, 95% CI 1.1-18.3, P = .04). The average niche depth was 5.7 ± 2.9 mm following Technique B with single-layer. CONCLUSION: Hysterotomy closure techniques determine the prevalence of post-Cesarean delivery niche formation and size. Exclusion of the endometrium at uterine closure reduces the development of significant scar defects.

Extreme enhanced myometrial vascularity following cesarean scar pregnancy: a new diagnostic entity.

OBJECTIVE: To define, illustrate and to follow-up the diagnosis, pathophysiology and treatment of a subset of the known enhanced myometrial vascularity (EMV): its extreme form, associated with cesarean scar pregnancies (CSP) and with some cases pf placenta accreta spectrum being at increased risk of significant bleeding complications. We also aim to provide guidance to the management of such cases. MATERIAL AND METHODS: This is an IRB-approved retrospective observational study of thirteen patients with an extreme form of EMV complicating CSPs. Patient's age, parity, number of cesarean deliveries, initial and time to negative serum hCG levels, primary and secondary diagnoses, blood flow peak systolic velocities, primary and secondary treatments, uterine artery embolization and outcomes were recorded. RESULTS: Gestational ages ranged 6-11 weeks at initial presentation. Initial serum hCG was 20.0-102.48 mIU/L (mean 44.4 mIU/L). Diameter of EMV reached 20-75 mm (mean 46.8 mm). The mean peak systolic velocity (PSV) was 84.2 cm/s (range 46.7-118.0). Primary treatments were: systemic methotrexate (MTX) alone; D&C alone; MTX and D&C; local and systemic intra-gestational MTX injection; double cervical ripening balloon with systemic MTX; misoprostol and D&C; emergent UAE. UAE and hysterectomy were the two main secondary treatments in 10 women except 1 having a D&C after UAE, and in 1 the lesion regressed without secondary treatment. Mean time to nonpregnant hCG levels was 21-122 days (mean 67.2). Mean follow-up was 110.2 days (range 26-160). Ten women were treated with UAE, 6 had one, 3 had two embolizations. Two women had hysterectomies, one of these for persistent bleeding. Based upon the common denominators of the clinical and the US pictures, our definition of extreme EMV is sustained form of EMV associated with treated or untreated CSP, with peak systolic velocities of blood flow over 50 cm/s, slow return or plateauing serum hCG, with or without clinically significant vaginal bleeding, unresponsive to initial or secondary treatment requiring uterine artery embolization or hysterectomy. CONCLUSION: The EMV developing in the background of retained placental tissue associated with CSP differs following the normal regression of the physiologically re-modelled, dilated vascular bed from the faulty "disrepair" of the vessel wall in in treated or untreated CSPs. The "threatening" appearance of the above EMVs warranted the term "extreme", creating their separate new sub-category." Extreme forms of CSP-related EMV pose significant diagnostic and management challenges. Prompt recognition and intervention, the proactive use of UAE, can maximize the outcome of women affected by this "extreme" form of EMV enabling to preserve reproductive potential. Obstetricians, gynecologists and interventional radiologists should be aware of this form of severe vascular complication.

WAPM-World Association of Perinatal Medicine Practice Guidelines: Fetal central nervous system examination.

These practice guidelines follow the mission of the World Association of Perinatal Medicine in collaboration with the Perinatal Medicine Foundation, bringing together groups and individuals throughout the world, with the goal of improving the ultrasound assessment of the fetal Central Nervous System (CNS) anatomy. In fact, this document provides further guidance for healthcare practitioners for the evaluation of the fetal CNS during the mid-trimester ultrasound scan with the aim to increase the ability in evaluating normal fetal anatomy. Therefore, it is not intended to establish a legal standard of care. This document is based on consensus among perinatal experts throughout the world, and serves as a guideline for use in clinical practice.

Outcome of cesarean scar pregnancy according to gestational age at diagnosis: A systematic review and meta-analysis.

OBJECTIVE: The association between the most severe types of placenta accreta spectrum disorders and caesarean scar pregnancy (CSP) poses the question of whether early diagnosis may impact the clinical outcome of these anomalies. The aim of this study is to report the outcome of cesarean scar pregnancy (CSP) diagnosed in the early (≤9 weeks) versus late (>9 weeks) first trimester of pregnancy. STUDY DESIGN: Medline, Embase and Clinicaltrail.gov databases were searched. Studies including cases of CSP with an early (≤9 weeks of gestation) compared to a late (>9 weeks) first trimester diagnosis of CSP, followed by immediate treatment, were included in this systematic review. The primary outcome was a composite measure of severe maternal morbidity including either severe first trimester bleeding, need for blood transfusion, uterine rupture or emergency hysterectomy. The secondary outcomes were the individual components of the primary outcome. Random-effect meta-analyses were used to combine data. RESULTS: Thirty-six studies (724 women with CSP) were included. Overall, composite adverse outcome complicated 5.9 % (95 % CI 3.5-9.0) of CSP diagnosed ≤9 weeks and 32.4 % (95 % CI 15.7-51.8) of those diagnosed >9 weeks. Massive hemorrhage occurred in 4.3 % (95 % CI 2.3-7.0) of women with early and in 28.0 % (95 % CI 14.1-44.5) of those with late first trimester diagnosis of CSP, while the corresponding figures for the need for blood transfusion were 1.5 % (95 % CI 0.6-2.8) and 15.8 % (95 % CI 5.5-30.2) respectively. Uterine rupture occurred in 2.5 % (95 % CI 1.2-4.1) of women with a prenatal diagnosis of CSP ≤ 9 weeks and in 7.5 % (95 % CI 2.5-14.9) of those with CSP > 9 weeks, while an emergency intervention involving hysterectomy was required in 3.7 % (95 % CI 2.2-5.4) and 16.3 % (95 % CI5.9-30.6) respectively. When computing the risk, early diagnosis of CSP was associated with a significantly lower risk of composite adverse outcome, (OR: 0.14; 95 % CI 0.1-0.4 p < 0.001). CONCLUSIONS: Early first trimester diagnosis of CSP is associated with a significantly lower risk of maternal complications, thus supporting a policy of universal screening for these anomalies in women with a prior cesarean delivery although the cost-effectiveness of such policy should be tested in future studies.

Special Report of the Society for Maternal-Fetal Medicine Placenta Accreta Spectrum Ultrasound Marker Task Force: Consensus on definition of markers and approach to the ultrasound examination in pregnancies at risk for placenta accreta spectrum.

Placenta accreta spectrum includes the full range of abnormal placental attachment to the uterus or other structures, encompassing placenta accreta, placenta increta, placenta percreta, morbidly adherent placenta, and invasive placentation. The incidence of placenta accreta spectrum has increased in recent years, largely driven by increasing rates of cesarean delivery. Prenatal detection of placenta accreta spectrum is primarily made by ultrasound and is important to reduce maternal morbidity associated with the condition. Despite a large body of research on various placenta accreta spectrum ultrasound markers and their screening performance, inconsistencies in the literature persist. In response to the need for standardizing the definitions of placenta accreta spectrum markers and the approach to the ultrasound examination, the Society for Maternal-Fetal Medicine convened a task force with representatives from the American Institute of Ultrasound in Medicine, the American College of Obstetricians and Gynecologists, the American College of Radiology, the International Society of Ultrasound in Obstetrics and Gynecology, the Society for Radiologists in Ultrasound, the American Registry for Diagnostic Medical Sonography, and the Gottesfeld-Hohler Memorial Ultrasound Foundation. The goals of the task force were to assess placenta accreta spectrum sonographic markers on the basis of available data and expert consensus, provide a standardized approach to the prenatal ultrasound evaluation of the uterus and placenta in pregnancies at risk of placenta accreta spectrum, and identify research gaps in the field. This manuscript provides information on the Placenta Accreta Spectrum Task Force process and findings.

Three-Dimensional Coronal Plane of the Uterus: A Critical View for Diagnostic Accuracy.

Two-dimensional transvaginal and transabdominal ultrasound (US) examinations are the suggested methods for examining the uterus. Three-dimensional (3D) US, which is not compulsory by society guidelines, provides additional uterine views, reassuring users of pathologic conditions not evident on customary sagittal and transverse views. The 3D coronal plane is rarely seen by 2-dimensional US transducers, let alone in extremely retroverted or axial uteri. Ultrasound machines nowadays feature 3D US capability. Our experience is that the coronal uterine view is a problem solver, helping diagnostic abilities of pelvic imaging. We advocate its liberal use and its acquisition in every pelvic scan. In this Pictorial Essay we present examples to demonstrate its use.

Reproductive outcome after cesarean scar pregnancy: A systematic review and meta-analysis.

INTRODUCTION: To evaluate subsequent reproductive among women with a prior cesarean scar pregnancy (CSP). MATERIAL AND METHODS: MEDLINE, Embase and ClinicalTrials.gov databases were searched. Inclusion criteria were women with a prior CSP, defined as the gestational sac or trophoblast within the dehiscence/niche of the previous cesarean section scar or implanted on top of it. The primary outcome was the recurrence of CSP; secondary outcomes were the chance of achieving a pregnancy after CSP, miscarriage, preterm birth, uterine rupture and the occurrence of placenta accreta spectrum disorders. Subgroup analysis according to the management of CSP (surgical vs non-surgical) was also performed. Random effect meta-analyses of proportions were used to analyze the data. RESULTS: Forty-four studies (3598 women with CSP) were included. CSP recurred in 17.6% of women. Miscarriage, preterm birth and placenta accreta spectrum disorders complicated 19.1% (65/341), 10.3% (25/243) and 4.0% of pregnancies, and 67.0% were uncomplicated. When stratifying the analysis according to the type of management, CSP recurred in 21% of women undergoing surgical and in 15.2% of those undergoing non-surgical management. Placenta accreta spectrum disorders complicated 4.0% and 12.0% of cases, respectively. CONCLUSIONS: Women with a prior CSP are at high risk of recurrence, miscarriage, preterm birth and placenta accreta spectrum. There is still insufficient evidence to elucidate whether the type of management adopted (surgical vs non-surgical) can impact reproductive outcome after CSP. Further large, prospective studies sharing an objective protocol of prenatal management and long-term follow up are needed to establish the optimal management of CSP and to elucidate whether it may affect its risk of recurrence and pregnancy outcome in subsequent gestations.

Society for Maternal-Fetal Medicine (SMFM) Consult Series #49: Cesarean scar pregnancy.

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

Cesarean Scar Pregnancy: Diagnosis and Pathogenesis.

Cesarean scar pregnancy is a potentially dangerous consequence of a previous cesarean delivery. If unrecognized and inadequately managed, it can lead to untoward complications throughout all three trimesters of the pregnancy. The rate of occurrence parallels the mounting rate of cesarean sections. The late consequences of cesarean delivery, such as placenta previa and placenta accrete, were known for a long time. However, it took more than a decade for the obstetric community to make the connection between the cesarean scar pregnancy and the placenta accreta spectrum. This article discusses the pathogenesis and diagnosis of cesarean scar pregnancy.