Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
35,279
result(s) for
"placenta"
Sort by:
Placenta Accreta Spectrum Disorders: Challenges, Risks, and Management Strategies
by
Morlando, Maddalena
,
Collins, Sally
in
abnormal invasive placenta
,
abnormal placentation
,
Cesarean section
2020
The worldwide incidence of placenta accreta spectrum (PAS) is rapidly increasing, following the trend of rising cesarean delivery. PAS is an heterogeneous condition associated with a high maternal morbidity and mortality rate, presenting unique challenges in its diagnosis and management. So far, the rarity of this condition, together with the absence of high quality evidence and the lack of a standardized approach in reporting PAS cases for the ultrasound, clinical, and pathologic diagnosis, represented the main challenges for a deep understanding of this condition. The study of the available management strategies of PAS has been hampered by the heterogeneity of the available epidemiological data on this condition. The aim of this review is to provide a critical view of the current available evidence on the screening, the diagnosis, and the management options for PAS disorders, with a special focus on the challenges we foresee for the near future.
Journal Article
The Underlying Molecular Mechanisms of the Placenta Accreta Spectrum: A Narrative Review
by
Cuén-Lazcano, Daniel E.
,
Gutiérrez-Grijalva, Erick Paul
,
Gutiérrez-Arzapalo, Perla Y.
in
Angiogenesis
,
Apoptosis
,
Biological control systems
2024
Placenta accreta spectrum (PAS) disorders are characterized by abnormal trophoblastic invasion into the myometrium, leading to significant maternal health risks. PAS includes placenta accreta (invasion < 50% of the myometrium), increta (invasion > 50%), and percreta (invasion through the entire myometrium). The condition is most associated with previous cesarean deliveries and increases in chance with the number of prior cesarians. The increasing global cesarean rates heighten the importance of early PAS diagnosis and management. This review explores genetic expression and key regulatory processes, such as apoptosis, cell proliferation, invasion, and inflammation, focusing on signaling pathways, genetic expression, biomarkers, and non-coding RNAs involved in trophoblastic invasion. It compiles the recent scientific literature (2014–2024) from the Scopus, PubMed, Google Scholar, and Web of Science databases. Identifying new biomarkers like AFP, sFlt-1, β-hCG, PlGF, and PAPP-A aids in early detection and management. Understanding genetic expression and non-coding RNAs is crucial for unraveling PAS complexities. In addition, aberrant signaling pathways like Notch, PI3K/Akt, STAT3, and TGF-β offer potential therapeutic targets to modulate trophoblastic invasion. This review underscores the need for interdisciplinary care, early diagnosis, and ongoing research into PAS biomarkers and molecular mechanisms to improve prognosis and quality of life for affected women.
Journal Article
Diagnostic accuracy of ultrasound in the diagnosis of Placenta accreta spectrum: systematic review and meta-analysis
by
Kamal, Nada
,
Ragab, Wael S.
,
Lasheen, Yossra
in
Accuracy
,
Cesarean Section
,
Cross-Sectional Studies
2023
Objective
To evaluate the diagnostic accuracy of ultrasound and in the diagnosis of Placenta accreta spectrum (PAS).
Data sources
Screening of MEDLINE, CENTRAL, other bases from inception to February 2022 using the keywords related to placenta accreta, increta, percreta, morbidly adherent placenta, and preoperative ultrasound diagnosis.
Study eligibility criteria
All available studies- whether were prospective or retrospective- including cohort, case control and cross sectional that involved prenatal diagnosis of PAS using 2D or 3D ultrasound with subsequent pathological confirmation postnatal were included. Fifty-four studies included 5307 women fulfilled the inclusion criteria, PAS was confirmed in 2025 of them.
Study appraisal and synthesis methods
Extracted data included settings of the study, study type, sample size, participants characteristics and their inclusion and exclusion criteria, Type and site of placenta previa, Type and timing of imaging technique (2D, and 3D), severity of PAS, sensitivity and specificity of individual ultrasound criteria and overall sensitivity and specificity.
Results
The overall sensitivity was 0.8703, specificity was 0.8634 with -0.2348 negative correlation between them. The estimate of Odd ratio, negative likelihood ratio and positive likelihood ratio were 34.225, 0.155 and 4.990 respectively.
The overall estimates of loss of retroplacental clear zone sensitivity and specificity were 0.820 and 0.898 respectively with 0.129 negative correlation. The overall estimates of myometrial thinning, loss of retroplacental clear zone, the presence of bridging vessels, placental lacunae, bladder wall interruption, exophytic mass, and uterovesical hypervascularity sensitivities were 0.763, 0.780, 0.659, 0.785, 0.455, 0.218 and 0.513 while specificities were 0.890, 0.884, 0.928, 0.809, 0.975, 0.865 and 0.994 respectively.
Conclusions
The accuracy of ultrasound in diagnosis of PAS among women with low lying or placenta previa with previous cesarean section scars is high and recommended in all suspected cases.
Trial registration
Number CRD42021267501.
Journal Article
Classification and reporting guidelines for the pathology diagnosis of placenta accreta spectrum (PAS) disorders: recommendations from an expert panel
by
Metlay, Leon A.
,
Baergen, Rebecca
,
Jacques, Suzanne M.
in
13/51
,
14/63
,
631/443/494/2732/2731
2020
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.
Journal Article
Combined First-Trimester PAPP-A and Free β-hCG Levels for the Early Diagnosis of Placenta Accreta Spectrum and Placenta Previa: A Case-Control Study
2025
Placenta accreta spectrum (PAS) and placenta previa (PP) are severe obstetric disorders associated with high maternal and perinatal morbidity. Early diagnosis of both conditions remains challenging, particularly in cases with subtle imaging findings. This study was aimed to evaluate the diagnostic value of first-trimester maternal serum levels of pregnancy-associated plasma protein-A (PAPP-A) and free beta subunit of human chorionic gonadotropin (β-hCG) in predicting PAS and PP. In this retrospective case–control study, a total of 100 pregnant women were included: 36 with PAS, 32 with PP, and 32 healthy controls. Serum levels were measured at 11–136 weeks of gestation. Both biomarkers were significantly altered in pathological groups compared to controls: PAPP-A was lower in PP (3.04 [1.42–4.52] IU/L) and PAS (3.63 [2.51–5.39] IU/L) vs. controls (5.34 [3.72–8.41] IU/L; p < 0.001), while β-hCG was higher in PP (45.4 [40.1–54.9] IU/L) and PAS (51.4 [32.3–74.8] IU/L) vs. controls (33.5 [22.7–54.1] IU/L; p = 0.044 and p < 0.001, respectively). ROC analysis demonstrated that combined biomarker modeling improved diagnostic accuracy over single-marker use, with AUCs reaching 0.85 (sensitivity 85.2%, specificity 72%) for PAS and 0.88 (sensitivity 100%, specificity 72%) for PP. These findings support the integration of biochemical screening into first-trimester risk assessment protocols. Incorporating maternal serum biomarkers may enhance early identification of high-risk pregnancies, allow timely referral to specialized care, and reduce adverse outcomes. Further prospective studies are warranted to validate the utility of this dual-marker approach across diverse populations and clinical settings.
Journal Article
Clinical analysis of second-trimester pregnancy termination after previous caesarean delivery in 51 patients with placenta previa and placenta accreta spectrum: a retrospective study
by
Luo, Lanrong
,
Li, Changdong
,
Zhang, Xiaofeng
in
Abortifacient Agents, Steroidal - therapeutic use
,
Abortion
,
Abortion, Induced - methods
2021
Backgrounds
Pregnancy termination during the second trimester in patients with placenta previa and placenta accreta spectrum (PAS) is a complex and challenging clinical problem. Based on our literature review, there has been a relative increase in the number of such cases being treated by hysterotomy and/or local uterine lesion resection and repair. In the present study, a retrospective analysis was conducted to compare the clinical outcomes when different management strategies were used to terminate pregnancy in the patients with placenta previa and PAS.
Methods
A total of 51 patients who underwent pregnancy termination in the second trimester in Beijing Obstetrics and Gynecology Hospital between June 2013 and December 2018 were retrospectively analyzed in this study. All patients having previous caesarean delivery (CD) were diagnosed with placenta previa status and PAS.
Results
① Among the 51 patients, 16 cases received mifepristone and misoprostol medical termination, 15 cases received mifepristone and Rivanol medical termination, but 1 of them was transferred to hysterotomy due to failed labor induction, another 20 cases were performed planned hysterotomy. There was no placenta percreta cases and uterine artery embolization (UAE) was all performed before surgery.② There were 31 cases who underwent medical termination and 30 cases were vaginal delivery. Dilation and evacuation (D&E) were used in 20 cases of medical abortion failure and in all 30 cases of difficult manual removal of placental tissue. ③ A statistically significant difference was found among the three different strategies in terms of gestational weeks, the type of placenta previa status, main operative success rate and β-HCG regression time (
P
< 0.05). ④ There were 4(7.8%) cases who were taken up for hysterectomy because of life-threatening bleeding or severe bacteremia during or after delivery and hysterotomy. The uterus was preserved with the implanted placenta partly or completely left in situ in 47(92.2%) cases. Combined medical and/or surgical management were used for the residual placenta and the time of menstrual recovery was 52(range: 33 to 86) days after pregnancy termination.
Conclusions
Terminating a pregnancy by vaginal delivery through medical induction of labor may be feasible if clinicians have an overall understanding of gestational age, the type of placenta previa status, the type of placenta accreta, and patients concerns about preserving fertility. A collaborative team effort in tertiary medical centers with a very experience MDT and combined application of multiple methods is required to optimize patient outcomes.
Journal Article
Shedding of Syncytiotrophoblast-Derived Extracellular Vesicles Is Increased in Placenta Previa and Accreta Spectrum
by
Vidiri, Annalisa
,
Di Simone, Nicoletta
,
Tersigni, Chiara
in
Adult
,
Biomarkers - blood
,
Biomarkers - metabolism
2024
Placenta accreta spectrum (PAS) refers to excessive placental invasion into the maternal uterus and it is associated with high risk of obstetric haemorrhage and adverse maternal-neonatal outcomes. Currently, no specific circulating biomarkers of PAS have been identified. Given that in PAS disorders, the depth and the extension of placental invasion into the uterus are expected to be increased, in this study, we analysed plasma levels of syncytiotrophoblast-derived extracellular vesicles (STBEVs) in women with placenta previa (PP), at a high risk of PAS disorders, and pregnant women with normal placentation. Venous blood samples were collected from 35 women with ultrasonographic diagnosis of PP and 35 women with normal placentation, matched for gestational age. Plasma samples were ultracentrifuged at 120.000 g to collect extracellular vesicles (EVs). To identify and quantify plasma placenta–derived EVs (or STBEVs), EVs were analysed by flow cytometry using a monoclonal antibody against placental alkaline phosphatase (PLAP). Plasma levels of STBEVs were significantly higher in PP patients compared to controls. Plasma levels of STBEVs in women with PP and PAS showed a trend to a higher concentration compared to women with PP without PAS, although not reaching a statistical significance. Circulating STBEVs are potential candidates as biological markers to be integrated to ultrasonography in the antenatal screening programme for PAS. More studies are needed to confirm our observation in a larger cohort of patients and to analyse a possible association between high circulating levels of STBEVs and PAS.
Journal Article
Human Placental Transcriptome Reveals Critical Alterations in Inflammation and Energy Metabolism with Fetal Sex Differences in Spontaneous Preterm Birth
2021
A well-functioning placenta is crucial for normal gestation and regulates the nutrient, gas, and waste exchanges between the maternal and fetal circulations and is an important endocrine organ producing hormones that regulate both the maternal and fetal physiologies during pregnancy. Placental insufficiency is implicated in spontaneous preterm birth (SPTB). We proposed that deficits in the capacity of the placenta to maintain bioenergetic and metabolic stability during pregnancy may ultimately result in SPTB. To explore our hypothesis, we performed a RNA-seq study in male and female placentas from women with SPTB (<36 weeks gestation) compared to normal pregnancies (≥38 weeks gestation) to assess the alterations in the gene expression profiles. We focused exclusively on Black women (cases and controls), who are at the highest risk of SPTB. Six hundred and seventy differentially expressed genes were identified in male SPTB placentas. Among them, 313 and 357 transcripts were increased and decreased, respectively. In contrast, only 61 differentially expressed genes were identified in female SPTB placenta. The ingenuity pathway analysis showed alterations in the genes and canonical pathways critical for regulating inflammation, oxidative stress, detoxification, mitochondrial function, energy metabolism, and the extracellular matrix. Many upstream regulators and master regulators important for nutrient-sensing and metabolism were also altered in SPTB placentas, including the PI3K complex, TGFB1/SMADs, SMARCA4, TP63, CDKN2A, BRCA1, and NFAT. The transcriptome was integrated with published human placental metabolome to assess the interactions of altered genes and metabolites. Collectively, significant and biologically relevant alterations in the transcriptome were identified in SPTB placentas with fetal sex disparities. Altered energy metabolism, mitochondrial function, inflammation, and detoxification may underly the mechanisms of placental dysfunction in SPTB.
Journal Article
Placental but Not Peripheral Plasmodium falciparum Infection During Pregnancy Is Associated With Increased Risk of Malaria in Infancy
by
Tomoka, Tamiwe
,
Laufer, Miriam K.
,
Mungwira, Randy
in
Chloroquine - therapeutic use
,
Drug Combinations
,
Female
2017
Pregnancy-associated Plasmodium falciparum infection impacts the health of mothers and newborns, but little is known about the effects of these infections on infant susceptibility to malaria. We followed 473 mother-infant pairs during pregnancy and through 2 years of age. We observed that children born to mothers with placental malaria, but not those born to mothers with peripheral infection without evidence of placental sequestration, had increased risk of malaria during the first year of life compared with children born to mothers with no malaria during pregnancy. Malaria infections with placental sequestration have long-lasting impact on infant susceptibility to malaria infection.
Journal Article