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Obstetrics and Gynecology 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; Conservative Treatment; Female; Fertility Preservation; Humans; Hysterectomy; Organ Sparing Treatments; Perioperative Care; Placenta Accreta; Pregnancy; Prenatal Diagnosis; Watchful Waiting
PubMed: 30461695
DOI: 10.1097/AOG.0000000000002983 -
American Journal of Obstetrics and... Sep 2022Placenta accreta has been described as a spectrum of abnormal attachment of villous tissue to the uterine wall, ranging from superficial attachment to the inner... (Review)
Review
Placenta accreta has been described as a spectrum of abnormal attachment of villous tissue to the uterine wall, ranging from superficial attachment to the inner myometrium without interposing decidua to transmural invasion through the entire uterine wall and beyond. These descriptions have prevailed for more than 50 years and form the basis for the diagnosis and grading of accreta placentation. Accreta placentation is essentially the consequence of uterine remodeling after surgery, primarily after cesarean delivery. Large cesarean scar defects in the lower uterine segment are associated with failure of normal decidualization and loss of the subdecidual myometrium. These changes allow the placental anchoring villi to implant, and extravillous trophoblast cells to migrate, close to the serosal surface of the uterus. These microscopic features are central to the misconception that the accreta placental villous tissue is excessively invasive and have led to much confusion and heterogeneity in clinical data. Progressive recruitment of large arteries in the uterine wall, that is, helicine, arcuate, and/or radial arteries, results in high-velocity maternal blood entering the intervillous space from the first trimester of pregnancy and subsequent formation of placental lacunae. Recently, guided sampling of accreta areas at delivery has enabled accurate correlation of prenatal imaging data with intraoperative features and histopathologic findings. In more than 70% of samples, there were thick fibrinoid depositions between the tip of most anchoring villi and the underlying uterine wall and around all deeply implanted villi. The distortion of the uteroplacental interface by these dense depositions and the loss of the normal plane of separation are the main factors leading to abnormal placental attachment. These data challenged the classical concept that placenta accreta is simply owing to villous tissue sitting atop the superficial myometrium without interposed decidua. Moreover, there is no evidence in accreta placentation that the extravillous trophoblast is abnormally invasive or that villous tissue can cross the uterine serosa into the pelvis. It is the size of the scar defect, the amount of placental tissue developing inside the scar, and the residual myometrial thickness in the scar area that determine the distance between the placental basal plate and the uterine serosa and thus the risk of accreta placentation.
Topics: Cicatrix; Female; Humans; Myometrium; Placenta; Placenta Accreta; Placentation; Pregnancy
PubMed: 35248577
DOI: 10.1016/j.ajog.2022.02.038 -
Best Practice & Research. Clinical... Nov 2019The increasing incidence of caesarean delivery (CD) has resulted in an increase in placenta accreta spectrum (PAS), adversely impacting maternal outcomes globally.... (Review)
Review
The increasing incidence of caesarean delivery (CD) has resulted in an increase in placenta accreta spectrum (PAS), adversely impacting maternal outcomes globally. Currently, more than 90% of women diagnosed with PAS present with a placenta praevia (praevia PAS). Praevia PAS can be reliably diagnosed antenatally with ultrasound, and it is unclear whether magnetic resonance imaging improves diagnosis beyond what can be achieved by skilled ultrasound operators. Therefore, any screening programme for PAS will require improved training in the diagnosis of placental disorders and development of targeted scanning protocols. Management strategies for praevia PAS vary depending on the accuracy of prenatal diagnosis, findings at laparotomy and local surgical expertise. Current epidemiological data for PAS are highly heterogeneous, mainly due to wide variation in the clinical criteria used to diagnose the condition at birth. This significantly impacts research into all aspects of the condition, especially comparison of the efficacy of different management strategies.
Topics: Cesarean Section; Female; Humans; Magnetic Resonance Imaging; Placenta Accreta; Placenta Previa; Pregnancy; Prenatal Diagnosis
PubMed: 31126811
DOI: 10.1016/j.bpobgyn.2019.04.006 -
American Journal of Obstetrics and... Jun 2022Placenta accreta spectrum is a life-threatening condition that has increased dramatically in recent decades along with cesarean rates worldwide. Cesarean hysterectomy is...
BACKGROUND
Placenta accreta spectrum is a life-threatening condition that has increased dramatically in recent decades along with cesarean rates worldwide. Cesarean hysterectomy is widely practiced in women with placenta accreta spectrum; however, the maternal outcomes after cesarean hysterectomy have not been thoroughly compared with the maternal outcomes after alternative approaches, such as conservative management.
OBJECTIVE
This study aimed to compare the severe maternal outcomes between women with placenta accreta spectrum treated with cesarean hysterectomy and those treated with conservative management (leaving the placenta in situ).
STUDY DESIGN
From a source population of 520,114 deliveries in 176 hospitals (PACCRETA study), we designed an observational cohort of women with placenta accreta spectrum who had either a cesarean hysterectomy or a conservative management (the placenta left in situ) during cesarean delivery. Clinicians prospectively identified women meeting the inclusion criteria and included them at delivery. Data collection started only after the women had received information and agreed to participate in the study in the immediate postpartum period. The primary outcome was the transfusion of >4 units of packed red blood cells within 6 months after delivery. Secondary outcomes were other maternal complications within 6 months. We used propensity score weighting to account for potential indication bias.
RESULTS
Here, 86 women had conservative management and 62 women had cesarean hysterectomy for placenta accreta spectrum during cesarean delivery. The primary outcome occurred in 14 of 86 women in the conservative management group (16.3%) and 36 of 61 (59.0%) in the cesarean hysterectomy group (risk ratio in propensity score weighted model, 0.29; 95% confidence interval, 0.19-0.45). The rates of hysterectomy, total estimated blood loss exceeding 3000 mL, any blood product transfusion, adjacent organ injury, and nonpostpartum hemorrhage-related severe maternal morbidity were lower with conservative management than with cesarean hysterectomy (all adjusted, P≤.02); but, the rates of arterial embolization, endometritis, and readmission within 6 months of discharge were higher with conservative management than with cesarean hysterectomy.
CONCLUSION
Among women with placenta accreta spectrum who underwent cesarean delivery, conservative management was associated with a lower risk of transfusion of >4 units of packed red blood cells within 6 months than cesarean hysterectomy.
Topics: Cesarean Section; Conservative Treatment; Female; Humans; Hysterectomy; Placenta Accreta; Pregnancy; Prospective Studies; Retrospective Studies
PubMed: 34914894
DOI: 10.1016/j.ajog.2021.12.013 -
The New England Journal of Medicine Sep 2021
Topics: Adult; Cesarean Section; Female; Humans; Obstetric Labor, Premature; Placenta Accreta; Postpartum Hemorrhage; Pregnancy; Uterus
PubMed: 34506088
DOI: 10.1056/NEJMicm2109363 -
American Journal of Obstetrics and... Sep 2020The evolution of multidisciplinary team-based care for women with placenta accreta spectrum disorder has delivered stepwise improvements in clinical outcomes. Central to... (Review)
Review
The evolution of multidisciplinary team-based care for women with placenta accreta spectrum disorder has delivered stepwise improvements in clinical outcomes. Central to this overall goal is the ability to limit blood loss at surgery. Placement of inflatable balloons within the pelvic arteries, most commonly in the anterior divisions of the internal iliac arteries, became popular in many centers, at the expense of prolonging surgical care and with attendant risks of vascular injury. In tandem, the need to expose pelvic sidewall anatomy to safely identify the course of the ureters re-popularized the alternative strategy of ligating the same anterior divisions of the internal iliac arteries. With incremental gains in surgical expertise, described in 5 steps in this review, our teams have witnessed a steady decline in surgical blood loss. Nevertheless, a subset of women has the most severe form of placenta accreta spectrum, namely placenta previa-percreta. Such women are at risk of major hemorrhage during surgery from vessels arising outside the territories of the internal iliac arteries. These additional blood supplies, mostly from the external iliac arteries, pose significant risks of major blood loss even in experienced hands. To address this risk, some centers, principally in China, have adopted an approach of routinely placing an infrarenal aortic balloon, with both impressively low rates of blood loss and an ability to conserve the uterus by resecting the placenta with the affected portion of the uterine wall. We review these literature developments in the context of safely performing elective cesarean hysterectomy for placenta previa-percreta, the most severe placenta accreta spectrum disorder.
Topics: Balloon Occlusion; Blood Loss, Surgical; Cesarean Section; Colpotomy; Female; Humans; Hysterectomy; Iliac Artery; Ligation; Magnetic Resonance Imaging; Placenta Accreta; Placenta Previa; Pregnancy; Risk Factors; Treatment Outcome
PubMed: 32007492
DOI: 10.1016/j.ajog.2020.01.044 -
NeoReviews Nov 2021Placenta accreta spectrum (PAS) refers to the range of pathologic adherence of the placenta to the uterine myometrium, including the placenta accreta, increta, and... (Review)
Review
Placenta accreta spectrum (PAS) refers to the range of pathologic adherence of the placenta to the uterine myometrium, including the placenta accreta, increta, and percreta. The incidence of PAS is rising primarily because of an increase in related risk factors, such as the rate of cesarean deliveries and pregnancies resulting from assisted reproductive technology. The maternal risks associated with PAS are significant, including hemorrhage, hysterectomy, and death. Fetal and neonatal risks are primarily the result of premature delivery. Antenatal diagnosis via ultrasonography and magnetic resonance imaging remains imperfect. Management of PAS varies, however, and there is a clear improvement in maternal outcomes with an antenatal diagnosis compared with unexpected diagnosis at the time of delivery. Studies that evaluate the balance between maternal and fetal/neonatal risks of expectant management versus preterm delivery have found that planned delivery between 34 and 35 weeks' gestation optimizes outcomes. Multidisciplinary PAS care teams have become the norm and recommended approach to management, given the complexity of caring for this obstetrical condition. Although significant advances have been made over the years, large knowledge gaps remain in understanding the pathophysiology, diagnosis, and clinical management.
Topics: Cesarean Section; Female; Gestational Age; Humans; Hysterectomy; Infant, Newborn; Placenta Accreta; Pregnancy; Prenatal Diagnosis
PubMed: 34725137
DOI: 10.1542/neo.22-11-e722 -
Journal of Midwifery & Women's Health Mar 2021Placenta accreta spectrum is a term used to describe abnormal adherence and abnormal invasion of the placenta into the uterine wall during pregnancy. The incidence of...
Placenta accreta spectrum is a term used to describe abnormal adherence and abnormal invasion of the placenta into the uterine wall during pregnancy. The incidence of placenta accreta spectrum has steadily increased over the last 40 years and is most notably linked to rising cesarean birth rates. This condition is associated with increased maternal morbidity and mortality because of the high risk of severe hemorrhage and likely need for hysterectomy at the time of birth. Early diagnosis of abnormal placentation is preferable in order to coordinate birth planning with a interprofessional collaborative team within a high-level perinatal care center. This article describes the case of a woman diagnosed with placenta accreta spectrum and the clinical course of her pregnancy and birth.
Topics: Cesarean Section; Female; Humans; Hysterectomy; Placenta; Placenta Accreta; Placenta Previa; Pregnancy
PubMed: 33338302
DOI: 10.1111/jmwh.13182 -
The New England Journal of Medicine Oct 2016
Topics: Adult; Female; Humans; Placenta; Placenta Accreta; Pregnancy; Ultrasonography, Prenatal
PubMed: 27705250
DOI: 10.1056/NEJMicm1513423 -
Current Opinion in Obstetrics &... Apr 2022Placenta accreta spectrum (PAS) is a major cause of severe maternal morbidity. Perinatal outcomes are significantly improved when PAS is diagnosed prenatally. However, a... (Review)
Review
PURPOSE OF REVIEW
Placenta accreta spectrum (PAS) is a major cause of severe maternal morbidity. Perinatal outcomes are significantly improved when PAS is diagnosed prenatally. However, a large proportion of cases of PAS remain undiagnosed until delivery.
RECENT FINDINGS
The prenatal diagnosis of PAS requires a high index of suspicion. The first step is identifying maternal risk factors. The most significant risk factor for PAS is the combination of a prior caesarean delivery and a placenta previa. Other major risk factors include a prior history of PAS, caesarean scar pregnancy (CSP), uterine artery embolization (UAE), intrauterine adhesions (Asherman syndrome) and endometrial ablation.Ultrasound is the preferred imaging modality for the prenatal diagnosis of PAS and can be highly accurate when performed by a provider with expertise. PAS can be diagnosed on ultrasound as early as the first trimester. MRI may be considered as an adjunct to ultrasound imaging but is not routinely recommended. Recent consensus guidelines outline the ultrasound and MRI markers of PAS.
SUMMARY
Patients with major risk factors for PAS warrant dedicated ultrasound imaging with a provider experienced in the prenatal diagnosis of PAS.
Topics: Female; Humans; Placenta Accreta; Placenta Previa; Pregnancy; Pregnancy Trimester, First; Prenatal Diagnosis; Uterine Artery Embolization
PubMed: 35230992
DOI: 10.1097/GCO.0000000000000773