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Pediatric Radiology Feb 2020The human placenta remains an enigma to many. Its position as the point of communication between distinct maternal and fetal circulations means that it must act as both... (Review)
Review
The human placenta remains an enigma to many. Its position as the point of communication between distinct maternal and fetal circulations means that it must act as both source of nourishment and gatekeeper for the developing pregnancy. In vivo assessment of the placenta is perhaps the greatest challenge, yet it is most essential for diagnostic and prognostic purposes. In particular, there is a need for improved diagnostic accuracy in recognizing the invasive forms of the placenta accreta spectrum that require surgical intervention at delivery and often cesarean hysterectomy. The costs of insufficient sensitivity and specificity are high, with well-documented cases of adverse outcomes ranging from unnecessary surgery to maternal hemorrhage and even death. In Part I of this pictorial essay series, we reviewed the appearance of the normal developing placenta across gestation by MRI. With this as a background, we here consider the varied appearances of the placenta accreta spectrum (placenta accreta, increta, percreta), which is a growing challenge given the rapidly expanding number of women worldwide with history of cesarean section delivery. Accurate prenatal imaging is crucial for recognizing cases of the placenta accreta spectrum and for planning the necessary surgery.
Topics: Female; Humans; Magnetic Resonance Imaging; Placenta; Placenta Accreta; Pregnancy
PubMed: 31975185
DOI: 10.1007/s00247-019-04521-2 -
Obstetrics and Gynecology Dec 2020The most common anomalies of implantation of the placenta and umbilical cord include placenta previa, placenta accreta spectrum, and vasa previa, and are associated with... (Review)
Review
The most common anomalies of implantation of the placenta and umbilical cord include placenta previa, placenta accreta spectrum, and vasa previa, and are associated with considerable perinatal and maternal morbidity and mortality. There is moderate quality evidence that prenatal diagnosis of these conditions improves perinatal outcomes and the performance of ultrasound imaging in diagnosing them is considered excellent. The epidemiology of placenta previa is well known, and it is standard clinical practice to assess placental location at the routine screening second-trimester detailed fetal anatomy ultrasound examination. In contrast, the prevalence of placenta accreta spectrum and vasa previa in the general population is more difficult to evaluate because detailed confirmatory histopathologic data are not available in most studies. The sensitivity and specificity of ultrasonography for the diagnosis of these anomalies is also difficult to assess. Recent epidemiologic studies show an increase in the incidence of placental and umbilical cord implantation anomalies, which may be the result of increased use of assisted reproductive technology and cesarean delivery. There is good evidence to support targeted standardized protocols for women at high risk and that screening and diagnosing placenta accreta spectrum and vasa previa should be integrated into obstetric ultrasound training programs.
Topics: Female; Humans; Placenta Accreta; Placenta Previa; Pregnancy; Pregnancy Outcome; Pregnancy Trimester, Second; Prenatal Diagnosis; Ultrasonography, Prenatal; Umbilical Cord; Vasa Previa
PubMed: 33156190
DOI: 10.1097/AOG.0000000000004175 -
Abdominal Radiology (New York) Dec 2022This study aimed to identify if placental thickness measured from MRI images correlated with placenta percreta in patients with placenta previa.
INTRODUCTION
This study aimed to identify if placental thickness measured from MRI images correlated with placenta percreta in patients with placenta previa.
METHODS
Placental thickness was retrospectively measured in 161 patients from July 2018 to August 2020. The measurements were performed at the thickest part of the placenta in the lower uterine segment on the mid-sagittal plane MR images by two independent radiologists. Intraoperative and pathologic findings were the standard of reference. Univariate and multivariate analyses were performed to identify the relationship between clinical features, placental thickness, and placenta percreta. The predictive ability of placental thickness was demonstrated using receiver operating characteristic curve analysis.
RESULTS
Placental thickness in patients with placenta percreta was significantly higher than in patients with placenta increta, placenta accreta, and normal placentas (p < 0.05). Multivariate analysis revealed that placental thickness was the only independent risk factor for placenta percreta. The cutoff value of placental thickness was 4.35 cm for differentiating placenta percreta in patients with placenta previa.
DISCUSSION
Patients with placenta percreta had the highest placental thickness. Placental thickness was correlated with placenta percreta.
Topics: Humans; Female; Pregnancy; Placenta Previa; Placenta Accreta; Placenta; Retrospective Studies; Magnetic Resonance Imaging
PubMed: 36114883
DOI: 10.1007/s00261-022-03676-1 -
Acta Obstetricia Et Gynecologica... Oct 2022The objective of this study was to assess the performance of ultrasound and magnetic resonance imaging (MRI) features in helping to classify the type of placenta accreta...
INTRODUCTION
The objective of this study was to assess the performance of ultrasound and magnetic resonance imaging (MRI) features in helping to classify the type of placenta accreta spectrum (PAS; accreta/increta vs percreta), alone or combined in a predictive score.
MATERIAL AND METHODS
We conducted a retrospective study in 82 pregnant women with PAS who underwent ultrasound and MRI examination of the pelvis before delivery (from an initial cohort of 185 women with PAS). We estimated the sensitivity, specificity and accuracy of MRI and ultrasound in the diagnosis of the type of PAS. We analyzed cesarean and imaging features using univariable logistic regression analysis. We constructed a nomogram to predict the risk of placenta percreta and validated it with bootstrap resampling, then used receiver operating characteristic curves to assess the performance of the model in distinguishing between placenta percreta and placenta accreta/increta.
RESULTS
Among the 82 patients, 29 (35%) had placenta accreta/increta and 53 (65%) had placenta percreta. The best features to discriminate between placenta accreta/increta and placenta percreta with ultrasound were increased vascularization at the uterine serosa-bladder wall interface (odds ratio [OR] 7.93; 95% confidence interval [CI] 2.78-24.99; p < 0.01) and the number of lacunae without a hyperechogenic halo (OR 1.36; 95% CI 1.14-1.67; p = 0.012). Concerning MRI markers, heterogeneous placenta (OR 12.89; 95% CI 3.05-89.16; p = 0.002), dark intraplacental bands (OR 12.89; 95% CI 3.05-89.16; p = 0.002) and bladder wall interruption (OR 15.89; 95% CI 4.78-73.33; p < 0.001) had a higher OR in discriminating placenta accreta/increta from placenta percreta. The nomogram yielded areas under the curve of 0.841 (95% CI 0.754-0.927) and 0.856 (95% CI 0.767-0.945), after bootstrap resampling, for the accurate prediction of placenta percreta.
CONCLUSIONS
The nomogram we developed to predict the risk of placenta percreta among patients with PAS had good discriminative capabilities. This performance and its impact on maternal morbidity should be confirmed by future prospective studies.
Topics: Female; Humans; Magnetic Resonance Imaging; Placenta; Placenta Accreta; Pregnancy; Prospective Studies; Retrospective Studies; Ultrasonography, Prenatal
PubMed: 35822244
DOI: 10.1111/aogs.14420 -
Indian Journal of Pathology &... Feb 2020Abnormal placentations such as placenta accreta, placenta increta and placenta percreta are important causes of hemorrhage after delivery causing maternal morbidity and...
BACKGROUND
Abnormal placentations such as placenta accreta, placenta increta and placenta percreta are important causes of hemorrhage after delivery causing maternal morbidity and mortality. Risk factors for abnormal placentation are prior caesarean section, placenta previa and pre-eclampsia. There is a need for reliable antenatal diagnosis for these serious conditions. If these pregnancies can be identified, antepartum, site and time of delivery as well as the surgical approach can be planned ahead; this decreases the incidence of maternal mortality due to massive hemorrhage.
AIM
(1) To study the incidence of abnormal placentation in emergency peripartum hysterectomy specimen. (2) To evaluate various risk factors associated with abnormal placentation.
MATERIALS AND METHOD
Retrospective cross-section study done in patients with abnormal placentation leading to emergency peripartum hysterectomy during a course of eight-year period.
RESULT
We received total of 18 emergency hysterectomy specimens during eight-year period of which placenta accreta accounts 55.5 percent (10/18), placenta increta upto 38.8 percent (7/18) and placenta percreta 5.5 percent (1/18). Analysis of result with parity shows uniparous women up to 22.2 percent (4/18), and multiparous women 77.7 percent (14/18). Risk factor analysis shows previous caesarean section in 55.5 percent (10/18), placenta previa in 33.3 percent (6/18) and pre-eclampsia in 11.1 percent (2/18).
CONCLUSION
In our study, among abnormal placentation, incidence of placenta accreta accounts for 55.5 percent and it is more common in multiparous women than uniparous women. Among risk factors in our study, previous caesarean section is commonly associated with abnormal placentation followed by a placenta previa and pre-eclampsia.
Topics: Adult; Cesarean Section; Cross-Sectional Studies; Female; Humans; Hysterectomy; Incidence; Peripartum Period; Placenta; Placenta Accreta; Placenta Previa; Pre-Eclampsia; Pregnancy; Retrospective Studies; Risk Factors
PubMed: 32108636
DOI: 10.4103/IJPM.IJPM_229_19 -
Archives of Gynecology and Obstetrics Dec 2019The incidence of placenta accreta spectrum (PAS; pathologic diagnosis of placenta accreta, increta or percreta) continues to rise in the USA. The purpose of this study...
PURPOSE
The incidence of placenta accreta spectrum (PAS; pathologic diagnosis of placenta accreta, increta or percreta) continues to rise in the USA. The purpose of this study is to compare the hemorrhagic morbidity associated with PAS with and without a placenta previa.
METHODS
This was a retrospective cohort study of 105 deliveries from 1997 to 2017 with histologically confirmed PAS comparing outcomes in women with and without a coexisting placenta previa. We used the Wilcoxon rank sum test to compare continuous data and Chi-square or Fisher's exact test for categorical data. We also performed log-binomial regression to calculate risk ratios adjusted for depth of invasion (aRR) and 95% confidence intervals (CI).
RESULTS
We identified 105 pregnancies with PAS. Antenatal diagnosis of PAS was higher in women with coexisting placenta previa (72.3%) than those without (6.9%, p < 0.001). Women with coexisting placenta previa had greater median estimated blood loss and more units of packed red blood cells transfused (both p ≤ 0.03). Women with placenta previa were more likely to undergo a hysterectomy (RR 2.7; 95% CI 1.8-3.8) and be admitted to the intensive care unit (aRR 3.3; 95% CI 1.1-9.6).
CONCLUSIONS
Among women with PAS, those with a coexisting placenta previa experienced greater hemorrhagic morbidity compared to those without. In addition, PAS without placenta previa typically was not diagnosed prior to delivery. This study further supports the recommendation for multi-disciplinary planning and assurance of resources for pregnancies complicated by PAS. In addition, our results highlight the need for mobilization of resources for those pregnancies where PAS is not diagnosed until delivery.
Topics: Adult; Female; Humans; Hysterectomy; Morbidity; Placenta Accreta; Placenta Previa; Postpartum Hemorrhage; Pregnancy; Retrospective Studies
PubMed: 31691015
DOI: 10.1007/s00404-019-05338-y -
American Journal of Obstetrics &... Dec 2023This study aimed to compare maternal outcomes of prenatally and nonprenatally diagnosed placenta accreta spectrum. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
This study aimed to compare maternal outcomes of prenatally and nonprenatally diagnosed placenta accreta spectrum.
DATA SOURCES
A systematic literature search was performed in PubMed, the Cochrane database, and Web of Science until November 28, 2022.
STUDY ELIGIBILITY CRITERIA
Studies comparing the clinical presentation of prenatally and nonprenatally diagnosed placenta accreta spectrum were included. The primary outcomes were emergent cesarean delivery, hysterectomy, blood loss volume, number of transfused blood product units, urological injury, coagulopathy, reoperation, intensive care unit admission, and maternal death. In addition, the pooled mean values for blood loss volume and the number of transfused blood product units were calculated. The secondary outcomes included maternal age, gestational age at birth, nulliparity, previous cesarean delivery, previous uterine procedure, assisted reproductive technology, placenta increta and percreta, and placenta previa.
METHODS
Study screening was performed after duplicates were identified and removed. The quality of each study and the publication bias were assessed. Forest plots and I statistics were calculated for each study outcome for each group. The main analysis was a random-effects analysis.
RESULTS
Overall, 415 abstracts and 157 full-text studies were evaluated. Moreover, 31 studies were analyzed. Prenatally diagnosed placenta accreta spectrum was associated with a significantly lower rate of emergency cesarean delivery (odds ratio, 0.37; 95% confidence interval, 0.21-0.67), higher hysterectomy rate (odds ratio, 1.98; 95% confidence interval, 1.02-3.83), lower blood loss volume (mean difference, -0.65; 95% confidence interval, -1.17 to -0.13), and lower number of transfused red blood cell units (mean difference, -1.96; 95% confidence interval, -3.25 to -0.68) compared with nonprenatally diagnosed placenta accreta spectrum. The pooled mean values for blood loss volume and the number of transfused blood product units tended to be lower in the prenatally diagnosed placenta accreta spectrum groups than in the nonprenatally diagnosed placenta accreta spectrum groups. Nulliparity (odds ratio, 0.14; 95% confidence interval, 0.10-0.20), previous cesarean delivery (odds ratio, 6.81; 95% confidence interval, 4.12-11.25), assisted reproductive technology (odds ratio, 0.19; 95% confidence interval, 0.06-0.61), placenta increta and percreta (odds ratio, 3.97; 95% confidence interval, 2.24-7.03), and placenta previa (odds ratio, 6.81; 95% confidence interval, 4.12-11.25) showed statistical significance. No significant difference was found for the other outcomes.
CONCLUSION
Despite its severity, the positive effect of prenatally diagnosed placenta accreta spectrum on outcomes underscores the necessity of a prenatal diagnosis. In addition, the pooled mean values provide a preoperative preparation guideline.
Topics: Pregnancy; Infant, Newborn; Female; Humans; Placenta Accreta; Placenta Previa; Cesarean Section; Intensive Care Units; Maternal Mortality
PubMed: 37865220
DOI: 10.1016/j.ajogmf.2023.101197 -
Best Practice & Research. Clinical... May 2022Placenta accreta spectrum (PAS) is a potentially life-threatening disorder with unique anesthetic challenges, and its incidence has increased over the past decades. We... (Review)
Review
Placenta accreta spectrum (PAS) is a potentially life-threatening disorder with unique anesthetic challenges, and its incidence has increased over the past decades. We review current guidelines and best practice evidence for antenatal diagnosis and preoperative evaluation, management pathways, multidisciplinary staff coordination, and surgery location. We address specific considerations for choice of anesthesia modality, the role of interventional radiology, and various techniques for minimizing hemorrhage for both planned and unplanned cases, as well as postoperative care for the PAS patient.
Topics: Anesthesia; Anesthetics; Cesarean Section; Female; Humans; Hysterectomy; Placenta; Placenta Accreta; Pregnancy
PubMed: 35659951
DOI: 10.1016/j.bpa.2022.01.003 -
The Journal of Maternal-fetal &... Aug 2019The objective of this study is to identify the maternal and neonatal outcomes in women with placenta increta or placenta percreta in China.
OBJECTIVE
The objective of this study is to identify the maternal and neonatal outcomes in women with placenta increta or placenta percreta in China.
MATERIALS AND METHODS
We retrospectively analyzed 2219 cases from 20 tertiary care centers in China between January 2011 and December 2015. All cases were diagnosed of placenta increta or placenta percreta, based on either intraoperative findings or histopathological findings.
RESULTS
The incidence of placenta increta and placenta percreta progressively increased from 0.18% in 2011 to 0.78% in 2015. Compared with the placenta increta, placenta percreta was strongly related to serious adverse outcomes: postpartum hemorrhage (65.9% versus 38.6%, p = .003), blood transfusion (86.2% versus 46.5%, p < .001), hysterectomy (43.3% versus 11.2%, p < .001), preterm birth (65.7% versus 49.9%, p < .001), and the need for neonatal intensive care unit (NICU) admission (54.5% versus 36.7%, p < .001).
CONCLUSION
The incidence of placenta increta and placenta percreta is likely to increase in China. The depth of placenta implantation is associated with the severity of outcomes. Placenta percreta tends to have worse maternal and neonatal outcomes.
Topics: Adult; China; Female; Humans; Hysterectomy; Incidence; Intensive Care Units, Neonatal; Placenta Accreta; Postpartum Hemorrhage; Pregnancy; Pregnancy Outcome; Premature Birth; Retrospective Studies; Severity of Illness Index
PubMed: 29514533
DOI: 10.1080/14767058.2018.1442429 -
Placenta Jun 2020Placenta accreta spectrum (PAS) is a major obstetrical problem whose incidence is rising. Current guidelines recommend screening of all women with placenta previa and... (Review)
Review
Placenta accreta spectrum (PAS) is a major obstetrical problem whose incidence is rising. Current guidelines recommend screening of all women with placenta previa and risk factors for PAS between 20 and 24 weeks. Risk factors, diagnosis, and management of previa PAS are well established, but an apparently normal location of the placenta does not exclude PAS. Literature data are scarce on uterine body PAS, which carries a high risk of maternal and neonatal adverse outcome, but is still easily missed on prenatal ultrasound. We conducted a comprehensive review to identify possible risk factors, clinical presentations, and diagnostic modalities of uterine PAS. A total of 133 cases were found during a 70-year period (1949-2019). The vast majority of them presented with signs of uterine rupture, even prior to the viability threshold of 24 weeks (up to 45%). Major risk factors included previous cesarean delivery, uterine curettage, uterine surgery, Asherman's syndrome, manual removal of the placenta, endometritis, high parity, young maternal age, in vitro fertilization, radiotherapy, uterine artery embolization, and uterine leiomyoma. Diagnosis was pre-symptomatic in only 3% of cases. Future studies should differentiate between previa PAS and uterine body PAS.
Topics: Female; Gestational Age; Humans; Maternal Age; Placenta; Placenta Accreta; Pregnancy; Risk Factors; Ultrasonography, Prenatal; Uterus
PubMed: 32452401
DOI: 10.1016/j.placenta.2020.04.005