Cesarean scar pregnancy is a precursor of morbidly adherent placenta

Screening for morbidly adherent placenta in early pregnancy

OBJECTIVE

To estimate the diagnostic accuracy of a two-stage strategy for early prediction of morbidly adherent placenta (MAP). In the first stage, at 11-13 weeks' gestation, women with low-lying placenta and history of uterine surgery are classified as being at high risk for MAP and, in the second stage, at 12-16 weeks, these high-risk pregnancies are assessed at a specialist MAP clinic.

METHODS

This was a prospective study in women having an ultrasound scan at 11-13 weeks' gestation as a part of routine pregnancy care. Women with low-lying placenta and a history of uterine surgery were followed up at a specialist MAP clinic at 12-16 weeks' gestation, 20-24 weeks and 28-34 weeks. At each visit to the MAP clinic, an ultrasound scan was carried out and the following features suggestive of MAP were recorded: non-visible Cesarean section scar; bladder wall interruption; thin retroplacental myometrium; presence of intraplacental lacunar spaces; presence of retroplacental arterial-trophoblastic blood flow; and irregular placental vascularization demonstrated by three-dimensional power Doppler.

RESULTS

Screening at 11-13 weeks was carried out in 22 604 singleton pregnancies, 1298 (6%) of which were considered to be at high risk of MAP because they had previous uterine surgery and low-lying placenta. At the MAP clinic at 12-16 weeks, the diagnosis of MAP was suspected in 14 cases and this was confirmed at delivery in 13. In the rest of the population, there were no cases of MAP.

CONCLUSION

Accurate prediction of MAP can be achieved by ultrasound examination at 12-16 weeks' gestation. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

The prevalence and risk predictors of cesarean scar defect at 6 weeks postpartum in Shanghai, China: A prospective cohort study

INTRODUCTION

The aim of this study was to explore the prevalence and predictors of cesarean scar defect (CSD) at 6 weeks postpartum in Shanghai, China.

MATERIAL AND METHODS

Women scheduled to receive a cesarean section (CS) were recruited from a university hospital. Surgery-related factors, pregnancy complications, routine examinations, perioperative medications, and physical signs were collected and transvaginal ultrasonography was performed to assess the presence of a CSD at 6 weeks postpartum. Multivariate logistic regression was applied to identify the predictors for CSD.

RESULTS

A CSD was detected in 223 of 514 women (43.4%, 95% CI 39.1%-47.7%) by transvaginal ultrasonography. Of women with normal temperature (T < 37.5°C, CSD prevalence 33.9%, 95% CI 28.4%-39.5%), women with postpartum fever (T ≥ 38°C, CSD 44.1%, 95% CI 31.0%-57.1%), and women who were subfebrile in the postpartum (37.5 ≤ T ≤ 38.0°C, CSD 58.3%, 95% CI 50.9%-65.7%), the latter two had significantly increased risk for CSD (adjusted odds ratio [aOR] 2.7, 95% CI 1.3-5.2 and aOR 3.3, 95% CI 2.1-5.3, respectively). In comparison to single-dose antibiotic administration (CSD 49.0%, 95% CI 43.8%-54.3%), multi-dose antibiotic administration (CSD 31.1%, 95% CI 23.8%-38.3%) had a protective effect (aOR 0.4, 95% CI 0.3-0.7). Postpartum fever, intrapartum infection, emergency CS, and cervical dilation ≥ 3 cm were found to be the main predictors of multi-dose antibiotics management. Low platelet count postpartum (defined as ≤ 150 × 10⁹ /L) and high fibrinogen pre-CS (defined as ≥ 4.5 g/L) increased CSD risk (aOR 2.0, 95% CI 1.1-3.6 and 1.7, 95% CI 1.1-2.5, respectively).

CONCLUSIONS

The prevalence of CSD in the Chinese population is high enough to be a concern. Perioperative infection and hypercoagulability should be considered CSD predictors, and multi-dose antibiotics have a protective effect.

Placenta Accreta Spectrum

Placenta accreta spectrum, formerly known as morbidly adherent placenta, refers to the range of pathologic adherence of the placenta, including placenta increta, placenta percreta, and placenta accreta. The most favored hypothesis regarding the etiology of placenta accreta spectrum is that a defect of the endometrial-myometrial interface leads to a failure of normal decidualization in the area of a uterine scar, which allows abnormally deep placental anchoring villi and trophoblast infiltration. Maternal morbidity and mortality can occur because of severe and sometimes life-threatening hemorrhage, which often requires blood transfusion. Although ultrasound evaluation is important, the absence of ultrasound findings does not preclude a diagnosis of placenta accreta spectrum; thus, clinical risk factors remain equally important as predictors of placenta accreta spectrum by ultrasound findings. There are several risk factors for placenta accreta spectrum. The most common is a previous cesarean delivery, with the incidence of placenta accreta spectrum increasing with the number of prior cesarean deliveries. Antenatal diagnosis of placenta accreta spectrum is highly desirable because outcomes are optimized when delivery occurs at a level III or IV maternal care facility before the onset of labor or bleeding and with avoidance of placental disruption. The most generally accepted approach to placenta accreta spectrum is cesarean hysterectomy with the placenta left in situ after delivery of the fetus (attempts at placental removal are associated with significant risk of hemorrhage). Optimal management involves a standardized approach with a comprehensive multidisciplinary care team accustomed to management of placenta accreta spectrum. In addition, established infrastructure and strong nursing leadership accustomed to managing high-level postpartum hemorrhage should be in place, and access to a blood bank capable of employing massive transfusion protocols should help guide decisions about delivery location.

Cesarean scar defect- obstetric consequences

Scope. This review aims to achieve a parallelism between literature studies on imaging diagnosis, the characteristics of cesarean scar defect and its evolution during pregnancy, and the obstetric consequences that can lead to increased maternal morbidity. Materials and Methods. There have been many literature studies published in recent years aimed to identify the methods of diagnosis for cesarean scar defect, the characteristics and the main changes of it during pregnancy, and the risks undertaken by pregnant women undergoing labor for vaginal delivery after a previous cesarean surgery. Results and Discussions. The most commonly used method for visualizing and evaluating uterine scar is transvaginal ultrasound in the first trimester of pregnancy, and abdominal ultrasonography in the II and III trimesters. The two areas characteristic of uterine scarring: "niche" and "thickness of the residual myometrium" undergo changes during the three trimesters of pregnancy. Some studies in the literature reported a higher incidence of uterine rupture, especially when the lower uterine segment fell below 2.3 mm, and a mean thickness of 3.2 mm, higher among multiparous women. A question that still does not have a generally valid answer refers to the hysterorrhaphy technique. There are different opinions among the authors, but most of them consider that after a double layer suture the thickness of the residual myometrium is higher. However, data from the literature show that the incidence of complications such as uterine rupture, dehiscence of the uterine trance are similar, regardless of the type of suture used. Another complication that occurs due to uterine scar is the pregnancy inserted at this level, which in the case of expectancy, leads to an increase in maternal and fetal morbidity. 50% of them evolve to spontaneous abortion in the first trimester, and almost all full-term pregnancies result in hysterectomy of necessity. Conclusions. Due to the many obstetrical and gynecological complications that occur on a uterine scar, an evaluation in dynamics is essential. There are no standardized protocols yet, but the identification and measurement of the uterine scar area in the third trimester may predict the chance of success of the labor test for vaginal delivery after cesarean surgery.

Prevention of Prematurity: Advances and Opportunities

Preterm birth (PTB) rate varies widely and has significant racial and ethnic disparities. Although causal mechanisms are ill understood, socioenvironment, phenotype, and genotype provide insight into pathways for preventing PTB. Data suggest varied response to current medical interventions is explicable Approved by underlying pharmacogenomics. Currently, prevention focuses on minimizing iatrogenic PTB and risk reduction especially in those with prior PTB using proven medical and public health strategies. In the future, preventive approaches will be based on better understanding of sociodemography, nutrition, lifestyles, and underlying individual genetic and epigenetic variation. Statistical approaches and "big-data" models are critical in future study.

Application of ultrasonography in the diagnosis and treatment of cesarean scar pregnancy

The morbidity of cesarean scar pregnancy (CSP) has shown an obvious ascending tendency with the increase of cesarean delivery in China and other countries. The timely diagnosis and treatment of CSP currently relies on medical imaging technology. In this article, we analyzed and compare the imaging methods in diagnosis of CSP. The imaging methods to diagnose CSP include traditional two-dimensional color/power Doppler ultrasound (2D-US), three-dimensional color/power Doppler ultrasound (3D-US), contrast-enhanced ultrasound (CEUS), and Magnetic Resonance Imaging (MRI). 2D-US provides important information including the location and size of gestational sac (GS), embryo with or without heart activity, and the relationship between the GS and scar. It can also divide CSP into different types, which are convenient for the choice of clinical treatment. CEUS can observe the perfusion of CSP in real-time, the arrival time of GS in CSP is earlier than that of the myometrium. It provides reliable evidence for diagnosis and evaluation of the treatment of CSP, which is helpful for making treatment plans and post-treatment follow-up. Combined use of ultrasound and CEUS could be a problem-solving method for CSP when conventional ultrasound is often inconclusive. Ultrasound has been accepted as the first-line imaging method and an important guiding method for CSP, supervising local methotrexate injection and curettage.

The Ethics of Interstitial and Cesarean Scar Ectopic Pregnancies: Four Case Studies and a Review of the Literature

Catholic bioethicists have extensively addressed extrauterine tubal pregnancies, which represent the great majority of ectopic pregnancies. However, additional management options have been developed for the other 7-10 percent of ectopic pregnancies. Using two cases of interstitial pregnancy and two cases of cesarean scar pregnancy (CSP) seen at a Catholic tertiary care center, this article discusses options including expectant management, systemic methotrexate, intragestational methotrexate, intragestational potassium chloride, uterine artery embolization, dilation and curettage (D&C), vasopressin use, cornuostomy, cornual wedge resection, CSP evacuation, CSP scar excision, CSP salvage, and hysterectomy. Cornual wedge resection, vasopressin use, and CSP scar excision are morally acceptable; less clearly licit are aspiration of gestational sac contents, cornuostomy, gestational excision for CSPs, and methotrexate. Certainly illicit are any techniques leading to direct abortion such as D&Cs on live embryos or fetuses, double-balloon catheter placement, and use of potassium chloride. Summary: An ectopic pregnancy is any pregnancy outside the uterus. These are dangerous because the pregnancy can burst out of its abnormal location and cause life-threatening internal bleeding. Most are in the part of the fallopian tube outside the uterus, but there are other types, including interstitial pregnancies (located in the part of the tube tunneling through the uterine wall) and cesarean scar pregnancies (buried in the uterine scar where the cut for a C-section was made). This article lists the ways that physicians prevent women from dying from interstitial and cesarean scar pregnancies and proposes which treatments are morally acceptable.

Caesarean scar pregnancy in the UK: a national cohort study

OBJECTIVE

To estimate the incidence of caesarean scar pregnancy (CSP) and to describe the management outcomes associated with this condition.

DESIGN

A national cohort study using the UK Early Pregnancy Surveillance Service (UKEPSS).

SETTING

86 participating Early Pregnancy Units.

POPULATION

All women diagnosed in the participating units with CSP between November 2013 and January 2015.

METHODS

Cohort study of women identified through the UKEPSS monthly mailing system.

MAIN OUTCOME MEASURES

Incidence, clinical outcomes and complications.

RESULTS

102 cases of CSP were reported, with an estimated incidence of 1.5 per 10 000 (95% CI 1.1-1.9) maternities. Full outcome data were available for 92 women. Management was expectant in 21/92 (23%), medical in 15/92 (16%) and surgical in 56/92 (61%). The success rates of expectant, medical and surgical management were 43% (9/21), 46% (7/15) and 96% (54/56), respectively. The complication rates were 15/21 (71%) with expectant, 9/15 (60%) with medical and 20/56 (36%) with surgical management. Discharge from care (median number of days) was 82 (range 37-174) with expectant, 21 (range 10-31) with medical and 11 (range 4-49) with surgical management.

CONCLUSIONS

Surgical management appears to be associated with a high success rate, low complication rate and short post-treatment follow up.

TWEETABLE ABSTRACT

Surgery for CSP appears to be successful, with low complication rates and short post-treatment follow up.

Expectant management of caesarean scar ectopic pregnancy: a systematic review

AIM

The purpose of this review is to systematically review all the reported cases and case series of caesarean scar pregnancy (CSP) managed expectantly without any intervention in order to understand the outcomes of pregnancy which will guide clinicians and patients in making treatment choices.

METHODS

An electronic search on PubMed, EMBASE and Cochrane databases and a manual search from references of the articles were performed. Studies were selected based on inclusion and exclusion criteria. Data were extracted for various outcomes of pregnancy and the quality of the reports was assessed using a modified Delphi technique.

RESULTS

A total of 56 cases of CSP from 11 reports were included in the review, including 44 cases with foetal cardiac activity. Live births were achieved in 73% of cases with a quarter of them born before 34 weeks. Hysterectomy rates were 70%. In 12/44 (27%) of cases pregnancies were lost due to complications before 24 weeks. Most (67%) of the CSPs with no foetal cardiac activities resolved on expectant management and the remaining required intervention for bleeding.

CONCLUSIONS

Caution should be exercised when choosing expectant management in cases of viable CSPs, and if chosen, the patient should be counselled adequately for possible outcomes including loss of pregnancy and hysterectomy. Expectant management is acceptable in CSPs with no foetal cardiac activity. There is a need for prospective research on this topic with adequate reporting on possible prognostic markers, as well as a need to improve on the techniques to prevent loss of fertility during delivery.

Pregnancy in an Abnormal Location

Cesarean scar pregnancy and cervical pregnancy are 2 relatively rare types of abnormally implanted pregnancies. Both if unrecognized can result in significant morbidity to the patient. The most important issue regarding cesarean scar pregnancy and cervical pregnancy is to establish the diagnosis early in order for the patient to be adequately counseled and appropriate management carried out. For both of these conditions early detection and treatment can result in preservation of fertility.

Uterine Artery Embolization Combined with Dilation and Curettage for the Treatment of Cesarean Scar Pregnancy: Efficacy and Future Fertility

PURPOSE

To investigate the efficacy and safety of uterine artery embolization (UAE) followed by dilation and curettage (D&C) as a treatment for cesarean scar pregnancy (CSP) and to assess pregnancy outcomes after the treatment.

MATERIALS AND METHODS

We retrospectively analyzed 33 CSP patients treated with UAE followed by D&C. The serum level of beta human chorionic gonadotropin (β-hCG) normalization, hospitalization, menstruation, and successful pregnancy after treatment was assessed as clinical and pregnancy outcomes.

RESULTS

A total of 33 patients were initially treated without severe complications. However, four patients required additional systemic chemotherapy. β-hCG normalization took 35.5 ± 14.9 days (range 13-79), and the hospitalization was 6.5 ± 2.5 days (2-15). All patients resumed normal menstruation after 36 ± 19.2 days (12-86). Of 16 of 33 patients who desired pregnancy after the treatment, seven patients (43.8%) had uneventful parturition.

CONCLUSIONS

UAE combined with D&C was efficient and safe for CSP management. This minimally invasive procedure may be considered as one of the treatment options which enable preservation of fertility after treatment.

Outcome of Cesarean scar pregnancy managed expectantly: systematic review and meta-analysis

OBJECTIVE

To explore the outcome in women managed expectantly following the diagnosis of Cesarean scar pregnancy (CSP).

METHODS

An electronic search of MEDLINE, EMBASE and ClinicalTrials.gov databases was performed utilizing combinations of relevant medical subject headings for 'Cesarean scar pregnancy' and 'outcome'. Reference lists of relevant articles and reviews were hand-searched for additional reports. Observed outcomes included: severe first-trimester vaginal bleeding; clinical symptoms (abdominal pain, vaginal bleeding) requiring treatment; uncomplicated miscarriage; complicated miscarriage requiring intervention; first- or second-trimester uterine rupture or hysterectomy; third-trimester bleeding, uterine rupture or hysterectomy; maternal death; incidence of abnormally invasive placenta (AIP); prevalence of placenta percreta; ultrasound signs suggestive of AIP; and live birth. Meta-analyses of proportions using a random-effects model were used to combine data. Cases were stratified based on the presence or absence of embryonic/fetal heart activity at the time of diagnosis.

RESULTS

A total of 17 studies (69 cases of CSP managed expectantly, 52 with and 17 without embryonic/fetal heart beat) were included. In women with CSP and embryonic/fetal heart activity, 13.0% (95% CI, 3.8-26.7%) experienced an uncomplicated miscarriage, while 20.0% (95% CI, 7.1-37.4%) required medical intervention. Uterine rupture during the first or second trimester of pregnancy occurred in 9.9% (95% CI, 2.9-20.4%) of cases, while hysterectomy was required in 15.2% (95% CI, 3.6-32.8%) of all cases. Forty (76.9% (95% CI, 65.4-86.5%)) women progressed to the third trimester of pregnancy, of whom 39.2% (95% CI, 15.4-66.2%) experienced severe bleeding. Finally, 74.8% (95% CI, 52.0-92.1%) had a surgical or pathological diagnosis of AIP at delivery and around two-thirds (69.7% (95% CI, 42.8-90.1%)) of them had placenta percreta. In women with CSP but no embryonic/fetal cardiac activity, an uncomplicated miscarriage occurred in 69.1% (95% CI, 47.4-87.1%) of cases, while surgical or medical intervention during or immediately after miscarriage was required in 30.9% (95% CI, 12.9-52.6%). Uterine rupture during the first trimester of pregnancy occurred in 13.4% (95% CI, 2.7-30.3%) of cases, but hysterectomy was not required in any case.

CONCLUSIONS

CSP with positive embryonic/fetal heart activity managed expectantly is associated with a high burden of maternal morbidity including severe hemorrhage, early uterine rupture, hysterectomy and severe AIP. Despite this, a significant proportion of pregnancies complicated by CSP may progress to, or close to, term, thus questioning whether termination of pregnancy should be the only therapeutic option offered to these women. Expectant management of CSP with no cardiac activity may be a reasonable option in view of the low likelihood of maternal complications requiring intervention, although close surveillance is advisable to avoid adverse maternal outcome. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

First-trimester detection of abnormally invasive placenta in high-risk women: systematic review and meta-analysis

OBJECTIVES

The primary aim of this systematic review was to ascertain whether ultrasound signs suggestive of abnormally invasive placenta (AIP) are present in the first trimester of pregnancy. Secondary aims were to ascertain the strength of association and the predictive accuracy of such signs in detecting AIP in the first trimester.

METHODS

An electronic search of MEDLINE, EMBASE, CINAHL and Cochrane databases (2000-2016) was performed. Only studies reporting on first-trimester diagnosis of AIP that was subsequently confirmed in the third trimester either during operative delivery or by pathological examination were included. Meta-analysis of proportions, random-effects meta-analysis and hierarchical summary receiver-operating characteristics curve analysis were used to analyze the data.

RESULTS

Seven studies, involving 551 pregnancies at high risk of AIP, were included. At least one ultrasound sign suggestive of AIP was detected in 91.4% (95% CI, 85.8-95.7%) of cases with confirmed AIP. The most common ultrasound feature in the first trimester of pregnancy was low implantation of the gestational sac close to a previous uterine scar, which was observed in 82.4% (95% CI, 46.6-99.8%) of cases. Anechoic spaces within the placental mass (lacunae) were observed in 46.0% (95% CI, 10.9-83.7%) and a reduced myometrial thickness in 66.8% (95% CI, 45.2-85.2%) of cases affected by AIP. Pregnancies with a low implantation of the gestational sac had a significantly higher risk of AIP (odds ratio, 19.6 (95% CI, 6.7-57.3)), with a sensitivity and specificity of 44.4% (95% CI, 21.5-69.2%) and 93.4% (95% CI, 90.5-95.7%), respectively.

CONCLUSIONS

Ultrasound signs of AIP can be present during the first trimester of pregnancy, even before 11 weeks' gestation. Low anterior implantation of the placenta/gestational sac close to or within the scar was the most commonly seen early ultrasound sign suggestive of AIP, although its individual predictive accuracy was not high. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

First-trimester prediction of surgical outcome in abnormally invasive placenta using the cross-over sign

OBJECTIVE

Ultrasound assessment of the relationship between the ectopic gestational sac and the endometrial line (cross-over sign; COS) in Cesarean scar pregnancy (CSP) has been shown to be useful in predicting the evolution of CSP towards different types of abnormally invasive placenta (AIP). The aim of this study was to ascertain whether the COS can be used to predict surgical outcome in women with AIP.

METHODS

A retrospective analysis was performed of early first-trimester (6-8 weeks' gestation) ultrasound images of women with AIP managed in the third trimester of pregnancy. We hypothesized that assessment of COS may identify cases of AIP at higher risk of intra- or postsurgical morbidity. Outcomes explored were estimated blood loss during surgery, need for and amount of packed red blood cells and fresh frozen plasma units required either during or after surgery, operative time, intrasurgical complications, gestational age at birth, delivery < 34 weeks of gestation, length of hospital stay and admission to intensive care unit. Differences in the explored outcomes were assessed among women with different types of COS variant (COS-1, COS-2+ or COS-2-) as observed on first-trimester ultrasound examination.

RESULTS

Sixty-eight pregnancies were included in the study. Mean estimated blood loss was higher in AIP pregnancies with COS-1 than in those with COS-2+ (P = 0.039) or COS-2- (P = 0.01). Mean number of packed red blood cell units required during or after the operation was higher in women with COS-1 compared with those with COS-2+ (P = 0.001) and COS-2- (P = 0.029), while there was no difference between pregnancies with COS-2+ and those with COS-2- (P = 0.797). Mean operative time was longer in AIP pregnancies with COS-1 than in those with COS-2+ (P = 0.039) or COS-2- (P = 0.017). Finally, pregnancies with COS-1 were delivered earlier than those with COS-2+ (P = 0.0001) or COS-2- (P = 0.0001).

CONCLUSION

First-trimester ultrasound assessment of the relationship between the ectopic gestational sac and the endometrial line (COS) may identify women with AIP who are at higher risk of intra- or postsurgical morbidity. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Placenta accreta spectrum disorder trends in the context of the universal two-child policy in China and the risk of hysterectomy

OBJECTIVE

To identify both the trends in placenta accreta spectrum (PAS) disorders in the context of the universal two-child policy in China and risk factors for hysterectomy.

METHODS

The present retrospective analysis included confirmed PAS disorders during cesarean delivery at a tertiary hospital in Changsha, Hunan, China, from January 1, 2007, to December 31, 2016. Multivariable logistic regression was used to estimate the risk of hysterectomy.

RESULTS

During the 10-year study period, the overall incidence of cesarean delivery was 51.6% (13 530/26 214) and that of PAS disorders was 1.2% (302/26 214). The PAS rate increased from 0.1% (5/4617) in 2007-2008 to 2.1% (133/6351) in 2015-2016, alongside a rise in elective repeat cesarean delivery from 5.0% (106/2124) to 38.4% (1385/3603). Previous cesarean delivery greatly increased the likelihood of PAS disorders (odds ratio [OR] 97.4; P<0.001). Invasive depth (OR 92.0; P<0.001), inter-cesarean interval less than 36 months (OR 7.0; P=0.002), rural residence (OR 5.3; P=0.018), and advanced maternal age (OR 3.0; P=0.045) were independent risk factors for hysterectomy among women with PAS disorders.

CONCLUSION

The increasing incidence of elective repeat cesarean delivery combined with a high overall rate of cesarean delivery implies a high prevalence of PAS disorders within the context of the universal two-child policy in China. The main predictor of hysterectomy was invasive depth.

Placental implantation abnormalities: a modern approach

PURPOSE OF REVIEW

Placental implantation abnormalities (PIAs) comprise a large group of disorders associated with significant maternal, fetal, and neonatal morbidity.

RECENT FINDINGS

Risk factors include prior uterine surgery/myometrial scarring and the presence of placenta previa with or without prior cesarean delivery. Newly identified risk factors include previous prelabor cesarean delivery and previous postpartum hemorrhage. PIAs contribute substantially to preterm birth with prematurity rates ranging from 38 to 82%. Diagnosis is typically made by ultrasound in the second or third trimester; transvaginal ultrasound and color Doppler are useful in evaluating for placental invasion, placental edge thickness, presence of fetal vessels, and cervical length. Suggestive MRI features include increased vascularity, dark T2 bands, uterine bulging, thin or indistinct myometrium, and loss of dark T2 interface. An important first-trimester finding is the implantation of the gestational sac into prior hysterotomy scar (cesarean scar pregnancy). Recommendations for delivery are universally preterm and based on expert opinion. Proposed management strategies are outlined depending on cervical length, distance between internal cervical os and placenta, and placental edge thickness.

SUMMARY

There has been a recent shift in focus to individualizing management in order to improve delivery timing and in some cases even decrease risks associated with prematurity. There is a need for larger prospective studies or randomized trials to show that individualizing care can improve outcomes.

Recurrent Cesarean Scar Ectopic Pregnancy Treated with Systemic Methotrexate

Cesarean scar pregnancy (CSP) is a rare event; however its incidence has been rising due to the increasing rates of cesarean deliveries. The majority of cases present with signs or symptoms requiring surgery, which often results in hysterectomy. The recurrence of CSP is even rarer with only few cases which have been reported. This is a report of recurrent cesarean scar ectopic pregnancy (RCSP) that was promptly diagnosed and managed with only systemic methotrexate. This was a 30-year-old woman, with a history of two prior cesarean deliveries followed by a CSP, who presented at 5 weeks and 3 days of gestation for her first prenatal visit. Transvaginal ultrasound revealed a RCSP. Her serum beta-human chorionic gonadotropin (β-hCG) level was 54,295 IU/L. The first CSP, which was diagnosed at a later stage, was treated with uterine artery embolization and systemic methotrexate leading to complete resolution within 10 weeks. The current ectopic was treated with two doses of systemic methotrexate; her serum β-hCG reached undetectable levels within 7 weeks. Thus, patients with a history of prior CSP should be carefully monitored with transvaginal ultrasound during subsequent pregnancies to allow early diagnosis of RCSP, which could then be treated conservatively.

3D power Doppler in the evaluation of abnormally invasive placenta

The anomalies in placental insertion and invasion, such as placenta previa and the various forms of abnormally invasive placenta, are today a rising obstetric pathology. Two-dimensional (2D) ultrasonography is the gold standard in the diagnosis of abnormally invasive placenta (AIP), but the important feto-maternal impact of this pathology suggests the opportunity to employ all the available diagnostic techniques, such as three-dimensional (3D) power Doppler. This technique allows acquiring multiplanar images on coronal, axial and sagittal planes and with a rotational technique, it permits visualizing the placenta-bladder interface more accurately. Consequently, it allows a better study of the degree of bladder invasion, which is information that has a great impact on the subsequent counseling and management. Thus, 3D power Doppler represents an important technique complementary to 2D ultrasound in the diagnosis of AIP. The aim of this paper is to illustrate the possible applications of this procedure, referring to the main literature data.

When a cesarean section scar is more than an innocent bystander in a subsequent pregnancy: Ultrasound to the rescue

Over the years, cesarean section has played a pivotal role in reducing maternal and perinatal morbidity and mortality. With the rising trend of this surgery, a substantial number of pregnant women have a cesarean section scar. The scar can serve as the abode of grave conditions in subsequent pregnancies, namely cesarean scar pregnancy, morbidly adherent placenta, and scar dehiscence. Sonography has emerged as a robust tool for the diagnosis of these potentially life-threatening conditions. This review highlights the key sonographic features of various complications that can occur at the cesarean scar site in subsequent pregnancies. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:319-327, 2017.

Natural history of Cesarean scar pregnancy on prenatal ultrasound: the crossover sign

OBJECTIVE

Advances in prenatal imaging techniques have led to an increase in the diagnosis of Cesarean scar pregnancy (CSP). However, antenatal counseling when CSP is diagnosed is challenging, and current evidence is derived mainly from small series reporting high rates of adverse maternal outcomes. The aim of this study was to ascertain the performance of prenatal ultrasound in predicting the natural history of CSP using a new sonographic sign, the crossover sign (COS).

METHODS

This was a retrospective analysis of early first-trimester (6-8 weeks' gestation) ultrasound images in women with morbidly adherent placenta (MAP) managed in the third trimester of pregnancy. The relationship between the gestational sac of the CSP, anterior uterine wall and Cesarean scar, defined as the COS, was analyzed to determine whether it could predict evolution in these cases. Odds ratios (ORs) were calculated and logistic regression analysis was performed to investigate the association between different types of COS (COS-1, COS-2+ or COS-2-) and the occurrence of MAP.

RESULTS

Sixty-eight pregnancies with MAP were included. The risk of placenta percreta was significantly higher in pregnancies with COS-1 than in those with COS-2 (OR, 6.67 (95% CI, 1.3-33.3)). When evaluating the two variants of COS-2 separately, the risk of placenta percreta was significantly higher in pregnancies with COS-1 vs COS-2+ (OR, 5.83 (95% CI, 1.1-30.2)) and this risk was even higher when comparing cases with COS-1 vs COS-2- (OR, 12.0 (95% CI, 1.9-75.7)). Logistic regression analysis showed that COS-1 was associated independently with severe forms of MAP, such as placenta percreta and increta (OR, 12.85 (95% CI, 2.0-84.0)), while COS-2+ was associated independently with placenta accreta (OR, 4.37 (95% CI, 1.1-17.0)).

CONCLUSIONS

Ultrasound assessment of the relationship between the gestational sac of a CSP and the endometrial line (the COS) may help to determine whether a CSP will progress towards a less severe form of MAP, amenable to postnatal treatment, and successful pregnancy outcome. Large prospective studies are needed to confirm our findings and elucidate the natural history of this condition. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Cesarean Hysterectomy and Uterine-Preserving Alternatives

Hysterectomy at the time of an obstetric delivery or postpartum is an uncommon time to perform one of the most common gynecologic procedures. Hysterectomy associated with pregnancy is often unplanned and undesired. Postpartum complications associated with the need for hysterectomy carry significant risks, which pose challenges for mother-infant bonding and can signify an unexpected end to fertility. The most common indication for hysterectomy is postpartum hemorrhage. Postpartum hemorrhage is caused by uterine atony, genital tract laceration, uterine rupture, invasive placentation, infection, or coagulopathy. Multidisciplinary teams improve outcomes and are capable of managing complex medical and surgical complications that occur postpartum.

The clinical outcome of cesarean scar pregnancies implanted "on the scar" versus "in the niche"

BACKGROUND

The term cesarean scar pregnancy refers to placental implantation within the scar of a previous cesarean delivery. The rising numbers of cesarean deliveries in the last decades have led to an increased incidence of cesarean scar pregnancy. Complications of cesarean scar pregnancy include morbidly adherent placenta, uterine rupture, severe hemorrhage, and preterm labor. It is suspected that cesarean scar pregnancies that are implanted within a dehiscent scar ("niche") behave differently compared with those implanted on top of a well-healed scar. To date there are no studies that have compared pregnancy outcomes between cesarean scar pregnancies implanted either "on the scar" or "in the niche."

OBJECTIVES

The purpose of this study was to determine the pregnancy outcome of cesarean scar pregnancy implanted either "on the scar" or "in the niche."

STUDY DESIGN

This was a retrospective 2-center study of 17 patients with cesarean scar pregnancy that was diagnosed from 5-9 weeks gestation (median, 8 weeks). All cesarean scar pregnancies were categorized as either implanted or "on the scar" (group A) or "in the niche" (group B), based on their first-trimester transvaginal ultrasound examination. Clinical outcomes based on gestational age at delivery, mode of delivery, blood loss at delivery, neonate weight and placental histopathologic condition were compared between the groups with the use of the Mann-Whitney U test. Myometrial thickness overlying the placenta was compared among all the patients who required hysterectomy and those who did not with the use of the Mann-Whitney U test. Myometrial thickness was also correlated with gestational age at delivery with the use of Spearman's correlation.

RESULTS

Group A consisted of 6 patients; group B consisted of 11 patients. Gestational age at delivery was lower in group B (median, 34 weeks; range, 20-36 weeks) than in group A (median, 38 weeks; range, 37-39 weeks; P=.001). In group A, 5 patients were delivered via cesarean delivery (with normal placenta), and 1 patient underwent a cesarean-hysterectomy for placenta accreta. In group B, 10 patients had a cesarean-hysterectomy for placenta increta/percreta, and 1 patient underwent gravid-hysterectomy for vaginal bleeding at 20 weeks gestation. Blood loss was increased, but not significantly higher in group B (median, 1200 mL; range, 600-4000 mL) than in group A (median, 700 mL; range, 600-1400 mL; P=.117). Myometrium was statistically significantly thinner in the patients group that require hysterectomy (median, 1 mm; range, 0-2 mm) than in the group that did not (median, 5 mm; range, 4-9 mm; P=.001). Myometrial thickness showed a positive correlation with the gestational age (r=0.820; P<.0005).

CONCLUSION

Patients with cesarean scar pregnancy implanted "on the scar" had a substantially better outcome compared with patients in whom the cesarean scar pregnancy implanted "in the niche." Myometrial thickness <2 mm in the first-trimester ultrasound examination is associated with morbidly adherent placenta at delivery.

Pitfalls and tips in the diagnosis of ectopic pregnancy

Women of reproductive age with pelvic pain, vaginal bleeding, and a positive pregnancy test often require evaluation with pelvic ultrasound. In these situations, the primary role of pelvic ultrasound is to differentiate an ectopic pregnancy from either a normal or abnormal intrauterine pregnancy. While an accurately performed and interpreted pelvic ultrasound results in rapid diagnosis and management, numerous diagnostic pitfalls can lead to negative outcomes. Therefore, familiarity with the appropriate laboratory tests, sonographic technique, and imaging features of ectopic pregnancy is essential for all radiologists. We present a review of ectopic pregnancy cases from our institution with attention to common pitfalls and troubleshooting tips for physicians who perform and interpret pelvic ultrasounds. We also present recently published literature to aid in the management of first trimester pregnancy.

Pitfalls in Ultrasound Diagnosis of Cesarean Scar Pregnancy

Cesarean scar pregnancy (CSP) is a rare kind of ectopic pregnancy implanted in the previous cesarean scar and has an increasing incidence over the past 30 years. As the suspicion is low, the diagnosis may be delayed or misinterpreted in ultrasound, leading to treatment strategies that might end up in uterine rupture or hysterectomy. The objective here is to review the ultrasound findings in CSP with varied presentations. Transabdominal and transvaginal sonography combined with color Doppler is a reliable tool for the diagnosis of CSP. When the gestational sac is seen in lower part of the uterine cavity, differentiation between threatened miscarriage, cervical pregnancy and CSP could be difficult. Not all cases of CSP present with typical ultrasound findings and a high index of suspicion is needed for diagnosis in these cases. An attempted curettage or MTP pill taken in an undiagnosed CSP often alters the typical findings. The possibility of CSP should also be considered in cases presenting with abnormal uterine bleeding and have a prior history of cesarean section. With lack of awareness about this condition, the diagnosis can often be missed either with MRI or in ultrasound. Correct interpretation and timely diagnosis save the mother from life-threatening complications and also preserves future fertility.

The gravid uterus: MR imaging and reporting of abnormal placentation

Appropriate placentation is critical to maternal and fetal outcomes. Abnormal placentation, including placenta previa and morbidly adherent placenta, is increasing in incidence and is associated with multiple risk factors including advanced maternal age and history of prior cesarean delivery. Magnetic resonance imaging (MRI) is increasingly used in assessing the type and extent of abnormal placentation, often leading to modifications in surgical approach. Here, we review the MRI features and appropriate reporting of placenta previa and the placenta accreta spectrum.

Accreta placentation: a systematic review of prenatal ultrasound imaging and grading of villous invasiveness

BACKGROUND

Determining the depth of villous invasiveness before delivery is pivotal in planning individual management of placenta accreta. We have evaluated the value of various ultrasound signs proposed in the international literature for the prenatal diagnosis of accreta placentation and assessment of the depth of villous invasiveness.

OBJECTIVE

We undertook a PubMed and MEDLINE search of the relevant studies published from the first prenatal ultrasound description of placenta accreta in 1982 through March 30, 2016, using key words "placenta accreta," "placenta increta," "placenta percreta," "abnormally invasive placenta," "morbidly adherent placenta," and "placenta adhesive disorder" as related to "sonography," "ultrasound diagnosis," "prenatal diagnosis," "gray-scale imaging," "3-dimensional ultrasound", and "color Doppler imaging."

STUDY DESIGN

The primary eligibility criteria were articles that correlated prenatal ultrasound imaging with pregnancy outcome. A total of 84 studies, including 31 case reports describing 38 cases of placenta accreta and 53 series describing 1078 cases were analyzed. Placenta accreta was subdivided into placenta creta to describe superficially adherent placentation and placenta increta and placenta percreta to describe invasive placentation.

RESULTS

Of the 53 study series, 23 did not provide data on the depth of villous myometrial invasion on ultrasound imaging or at delivery. Detailed correlations between ultrasound findings and placenta accreta grading were found in 72 cases. A loss of clear zone (62.1%) and the presence of bridging vessels (71.4%) were the most common ultrasound signs in cases of placenta creta. In placenta increta, a loss of clear zone (84.6%) and subplacental hypervascularity (60%) were the most common ultrasound signs, whereas placental lacunae (82.4%) and subplacental hypervascularity (54.5%) were the most common ultrasound signs in placenta percreta. No ultrasound sign or a combination of ultrasound signs were specific of the depth of accreta placentation.

CONCLUSION

The wide heterogeneity in terminology used to describe the grades of accreta placentation and differences in study design limits the evaluation of the accuracy of ultrasound imaging in the screening and diagnosis of placenta accreta. This review emphasizes the need for further prospective studies using a standardized evidence-based approach including a systematic correlation between ultrasound signs of placenta accreta and detailed clinical and pathologic examinations at delivery.

A new minimally invasive treatment for cesarean scar pregnancy and cervical pregnancy

BACKGROUND

Cesarean scar pregnancy and cervical pregnancy are unrelated forms of pathological pregnancies carrying significant diagnostic and treatment challenges, with a wide range of treatment effectiveness and complication rates ranging from 10% to 62%. At times, life-saving hysterectomy and uterine artery embolization are required to treat complications. Based on our previous success with using a single-balloon catheter for the treatment of cesarean scar pregnancy after local injection of methotrexate, we evaluated the use of a double-balloon catheter to terminate the pregnancy while preventing bleeding without any additive treatment. This was a retrospective study.

OBJECTIVES

The objective of the study was to describe the placement of a cervical ripening double-balloon catheter as a novel, minimally invasive treatment in patients with cesarean scar and cervical pregnancies to terminate the pregnancy and at the same time prevent bleeding by compressing the blood supply of the gestational sac.

STUDY DESIGN

Patients with diagnosed, live cervical pregnancy and cesarean scar pregnancy between 6 and 8 weeks' gestation were considered for the office-based treatment. Paracervical block with 1% lidocaine was administered in 3 patients for pain control. Insertion of the catheter and inflation of the upper balloon were done under transabdominal ultrasound guidance. The lower (pressure) balloon was inflated opposite the gestational sac under transvaginal ultrasound guidance. After an hour, the area of the sac was scanned. When fetal cardiac activity was absent and no bleeding was noted, patients were discharged. After 2-3 days, a follow-up appointment was scheduled for possible catheter removal. Serial ultrasound (US) and serum human chorionic gonadotropin were followed weekly or as needed.

RESULTS

Three live cervical pregnancies and 7 live cesarean scar pregnancies were successfully treated. Median gestational age at treatment was 6 6/7 weeks (range 6 1/7 through 7 4/7 weeks). Patients' acceptance for the double-balloon treatment was high in spite of the initial low abdominal pressure felt at the inflation of the balloons. All but 1 patient noted vaginal spotting at the follow-up appointment. Only 1 patient experienced bleeding of dark blood. The balloons were in place for a median of 3 days (range, 1-5 days). Median time from treatment to the total drop of human chorionic gonadotropin was 49 days (range, 28-97 days).

CONCLUSION

The double balloon is a successful, minimally invasive and well-tolerated single treatment for cervical pregnancy and cesarean scar pregnancy. This simple treatment method has 4 main advantages: it effectively stops embryonic cardiac activity, prevents bleeding complications, does not require any additional invasive therapies, and is familiar to obstetricians-gynecologists who use the same cervical ripening catheters for labor induction. Its wider application, however, has to be validated on a larger patient population.

Placenta Increta Complicating Persistent Cesarean Scar Ectopic Pregnancy following Failed Excision with Subsequent Preterm Cesarean Hysterectomy

Introduction. Cesarean scar pregnancies (CSPs) are one of the rarest forms of ectopic pregnancy. Given their rarity, there is lack of consensus regarding the management and natural course of CSPs. Case. A 37-year-old G10 P3063 female with a history of two prior cesarean deliveries was diagnosed with her second CSP at 6 weeks and 5 days in her tenth pregnancy. The patient underwent vertical hysterotomy, excision of a gestational sac implanted in the cesarean sac, and bilateral salpingectomy via a laparotomy incision. The histopathology report confirmed immature chorionic villi. The patient returned 10 weeks later and was found to be still pregnant. Obstetric ultrasound confirmed a viable fetus of 19 weeks and 4 days of gestational age with a thin endometrium and an anteroposterior and right lateral placenta with multiple placental lakes. The patient ruptured her membranes at 31 weeks of gestation and pelvic MRI revealed an anterior placenta invading the myometrium and extending to the external serosal surface consistent with placenta increta. Following obstetric interventions, a live female infant was delivered by cesarean hysterectomy (because of placenta increta) at 32 weeks of gestation. Conclusion. Development of standardized guidelines for management of CSPs, as well as heightened vigilance for possible complications, is required for proper care and avoidance of potential morbidity and mortality.

Placenta Accreta and Placenta Increta: An Approach to Pathogenesis Based on the Trophoblastic Differentiation Pathway

Morbid adherence remains a puzzling disease. This paper suggests that normal and morbidly adherent placentation may be viewed best in terms of trophoblastic stem cells and the mutually exclusive branches of the trophoblastic differentiation pathway-villous trophoblast (VT), interstitial and endovascular nonvillous trophoblast (NVT) at the implantation site, and a positional variation in the chorion. Based on cases of hysterectomies for morbid adherence seen over 30 years at a community hospital, analyzed with routine keratin stains, with actin and trichrome stains as indicated, and with attempts at ultrasonography-pathology correlation, we present selected observations. In true accreta, the site of morbid adherence was to dilated basal plate vessels infiltrated by endovascular NVT, with scant interstitial NVT, and normal myometrium. It appeared that excess blood flow into the placenta was due to excessively deep keratin-positive endovascular NVT that spread-independently of interstitial NVT-in an angiocentric fashion in both accreta and increta. Retroplacental abnormalities were due to myometrial destruction by interstitial NVT in increta, sometimes requiring actin stains for detection; and to an admixture of markedly dilated endometrial glands and vessels in true accreta, best appreciated with keratin stains. Variations of depth and extent in increta may be due to variations in myometrial tone, and in the protease-antiprotease balance. Morbidly adherent fetal membranes are described, and the role of caesarean section scars in incretas is addressed.

Incorporating uterine artery embolization in the treatment of cesarean scar pregnancy following diagnostic ultrasonography

OBJECTIVE

To evaluate combining uterine artery embolization (UAE) with other treatments for cesarean scar pregnancy (CSP).

METHODS

A retrospective study included patients attending the First affiliated Hospital of Xi'an Jiaotong University, China, between March 1, 2009 and March 31, 2014, who were diagnosed with CSP. Patients were classified by ultrasonography as having endogenous CSP (CSP type I [CSP-I]) or exogenous CSP (CSP type II [CSP-II]). Patient outcomes were compared between patients who underwent treatment that included or excluded UAE. Patient records were reviewed and patients were interviewed by telephone to report on recovery following treatment.

RESULTS

In total, 52 patients met the inclusion criteria. In patients with CSP-I, the blood loss, length of hospital stay, and time before restoration of normal β human chorionic gonadotropin levels were significantly higher in patients who were treated with methotrexate combined with dilatation and curettage compared with those treated with UAE combined with dilatation and curettage (P<0.05). In patients with CSP-II, blood loss was lower in patients treated with UAE combined with excision compared with excision alone (P<0.001).

CONCLUSION

Incorporating UAE in the treatment of CSP-I and CSP-II was safe; CSP should be properly classified to select the appropriate treatment.