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American Journal of Obstetrics and... Jan 2018Placenta accreta spectrum is a complex obstetric complication associated with high maternal morbidity. It is a relatively new disorder of placentation, and is the... (Review)
Review
Placenta accreta spectrum is a complex obstetric complication associated with high maternal morbidity. It is a relatively new disorder of placentation, and is the consequence of damage to the endometrium-myometrial interface of the uterine wall. When first described 80 years ago, it mainly occurred after manual removal of the placenta, uterine curettage, or endometritis. Superficial damage leads primarily to an abnormally adherent placenta, and is diagnosed as the complete or partial absence of the decidua on histology. Today, the main cause of placenta accreta spectrum is uterine surgery and, in particular, uterine scar secondary to cesarean delivery. In the absence of endometrial reepithelialization of the scar area the trophoblast and villous tissue can invade deeply within the myometrium, including its circulation, and reach the surrounding pelvic organs. The cellular changes in the trophoblast observed in placenta accreta spectrum are probably secondary to the unusual myometrial environment in which it develops, and not a primary defect of trophoblast biology leading to excessive invasion of the myometrium. Placenta accreta spectrum was separated by pathologists into 3 categories: placenta creta when the villi simply adhere to the myometrium, placenta increta when the villi invade the myometrium, and placenta percreta where the villi invade the full thickness of the myometrium. Several prenatal ultrasound signs of placenta accreta spectrum were reported over the last 35 years, principally the disappearance of the normal uteroplacental interface (clear zone), extreme thinning of the underlying myometrium, and vascular changes within the placenta (lacunae) and placental bed (hypervascularity). The pathophysiological basis of these signs is due to permanent damage of the uterine wall as far as the serosa, with placental tissue reaching the deep uterine circulation. Adherent and invasive placentation may coexist in the same placental bed and evolve with advancing gestation. This may explain why no single, or set combination of, ultrasound sign(s) was found to be specific for the depth of abnormal placentation, and accurate for the differential diagnosis between adherent and invasive placentation. Correlation of pathological and clinical findings with prenatal imaging is essential to improve screening, diagnosis, and management of placenta accreta spectrum, and standardized protocols need to be developed.
Topics: Female; Humans; Myometrium; Placenta; Placenta Accreta; Placenta Previa; Placentation; Pregnancy; Ultrasonography, Prenatal; Urinary Bladder; Vascular Remodeling
PubMed: 28599899
DOI: 10.1016/j.ajog.2017.05.067 -
American Journal of Obstetrics and... Dec 2018Placenta accreta spectrum, formerly known as morbidly adherent placenta, refers to the range of pathologic adherence of the placenta, including placenta increta,...
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.
Topics: Cesarean Section; Female; Gynecology; Humans; Hysterectomy; Obstetrics; Placenta Accreta; Pregnancy; Prenatal Diagnosis; Societies, Medical; United States
PubMed: 30471891
DOI: 10.1016/j.ajog.2018.09.042 -
International Journal of Gynaecology... Jul 2019Placenta accreta spectrum is impacting maternal health outcomes globally and its prevalence is likely to increase. Maternal outcomes depend on identification of the... (Review)
Review
Placenta accreta spectrum is impacting maternal health outcomes globally and its prevalence is likely to increase. Maternal outcomes depend on identification of the condition before or during delivery and, in particular, on the differential diagnosis between its adherent and invasive forms. However, accurate estimation of its prevalence and outcome is currently problematic because of the varying use of clinical criteria to define it at birth and the lack of detailed pathologic examination in most series. Adherence to this new International Federation of Gynecology and Obstetrics (FIGO) classification should improve future systematic reviews and meta-analyses and provide more accurate epidemiologic data which are essential to develop new management strategies.
Topics: Adult; Delivery, Obstetric; Female; Humans; Perinatal Care; Placenta Accreta; Pregnancy
PubMed: 31173360
DOI: 10.1002/ijgo.12761 -
Obstetrics and Gynecology Clinics of... Sep 2022The incidence of placenta accreta spectrum (PAS) is increasing and is now about 3 per 1000 deliveries, largely due to the rising cesarean section rate. Ultrasound is the... (Review)
Review
The incidence of placenta accreta spectrum (PAS) is increasing and is now about 3 per 1000 deliveries, largely due to the rising cesarean section rate. Ultrasound is the preferred method for diagnosis of PAS. Ultrasound markers include multiple vascular lacunae, loss of the hypoechoic retroplacental zone, abnormalities of the uterine serosa-bladder interface, retroplacental myometrial thickness less than 1 mm, increased placental vascularity, and observation of bridging vessels linking the placenta and bladder. Patients with PAS should be managed by experienced multidisciplinary teams. Hysterectomy is the accepted management of PAS and conservative or expectant management of PAS should be considered investigational.
Topics: Cesarean Section; Female; Humans; Placenta; Placenta Accreta; Pregnancy; Prenatal Diagnosis; Ultrasonography, Prenatal
PubMed: 36122977
DOI: 10.1016/j.ogc.2022.02.004 -
BJOG : An International Journal of... Jan 2019
Topics: Cesarean Section; Female; Humans; Placenta Accreta; Placenta Previa; Pregnancy; Premature Birth; Risk Factors; Ultrasonography, Prenatal
PubMed: 30260097
DOI: 10.1111/1471-0528.15306 -
European Journal of Obstetrics,... Apr 2021Placenta accreta spectrum (PAS) is an umbrella term for a variety of pregnancy complications due to abnormal placental implantation, including placenta accreta, placenta... (Review)
Review
Placenta accreta spectrum (PAS) is an umbrella term for a variety of pregnancy complications due to abnormal placental implantation, including placenta accreta, placenta increta and placenta percreta. During the past several decades, the prevalence of PAS has been increasing, and the clinical importance of this disease is significant because of the severe complications. In this review, we summarized the available evidence-based data for PAS in various aspects: prevalence, risk factors, pathogenesis, clinical presentation and prenatal screening, and clinical management. Meanwhile, we provided a series of prospects in each section for further studies on PAS. Moreover, we first present a visualized workflow for the management of PAS from three steps: predelivery, during delivery and postdelivery.
Topics: Female; Humans; Placenta; Placenta Accreta; Placenta Previa; Pregnancy; Prenatal Diagnosis; Risk Factors
PubMed: 33601317
DOI: 10.1016/j.ejogrb.2021.02.001 -
Modern Pathology : An Official Journal... Dec 2020The terminology and diagnostic criteria presently used by pathologists to report invasive placentation is inconsistent and does not reflect current knowledge of the... (Review)
Review
The terminology and diagnostic criteria presently used by pathologists to report invasive placentation is inconsistent and does not reflect current knowledge of the pathogenesis of the disease or the needs of the clinical care team. A consensus panel was convened to recommend terminology and reporting elements unified across the spectrum of PAS specimens (i.e., delivered placenta, total or partial hysterectomy with or without extrauterine tissues, curetting for retained products of conception). The proposed nomenclature under the umbrella diagnosis of placenta accreta spectrum (PAS) replaces the traditional categorical terminology (placenta accreta, increta, percreta) with a descriptive grading system that parallels the guidelines endorsed by the International Federation of Gynaecology and Obstetrics (FIGO). In addition, the nomenclature for hysterectomy specimens is separated from that for delivered placentas. The goal for each element in the system of nomenclature was to provide diagnostic criteria and guidelines for expected use in clinical practice.
Topics: Biopsy; Consensus; Documentation; Female; Forms and Records Control; Humans; Hysterectomy; Medical Records; Pathology, Clinical; Placenta; Placenta Accreta; Placentation; Predictive Value of Tests; Pregnancy; Severity of Illness Index; Terminology as Topic
PubMed: 32415266
DOI: 10.1038/s41379-020-0569-1 -
The New England Journal of Medicine Apr 2018
Review
Topics: Adult; Anesthesia, Obstetrical; Cesarean Section; Female; Hemorrhage; Humans; Hysterectomy; Placenta Accreta; Placenta Previa; Pregnancy; Risk Factors; Ultrasonography, Prenatal
PubMed: 29669225
DOI: 10.1056/NEJMcp1709324 -
CMAJ : Canadian Medical Association... Aug 2020
Review
Topics: Cesarean Section; Female; Humans; Hysterectomy; Placenta Accreta; Placenta Previa; Pregnancy; Risk Factors
PubMed: 32839166
DOI: 10.1503/cmaj.200304 -
American Journal of Obstetrics and... Jan 2021Placenta accreta spectrum includes the full range of abnormal placental attachment to the uterus or other structures, encompassing placenta accreta, placenta increta,...
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.
Topics: Cesarean Section; Cicatrix; Female; Gestational Age; Gynecology; Humans; Obstetrics; Placenta; Placenta Accreta; Pregnancy; Sensitivity and Specificity; Societies, Medical; Ultrasonography, Prenatal; United States; Uterus
PubMed: 33386103
DOI: 10.1016/j.ajog.2020.09.001