Abnormal placentation

Imaging of the Placenta

Placental imaging is crucial in prenatal care, offering insights into both normal and abnormal pregnancies. Traditional methods like grayscale ultrasound and magnetic resonance imaging evaluate placental anatomy, whereas Doppler ultrasound is used for functional assessment. Recent advancements include functional magnetic resonance imaging and advanced Doppler software for demonstrating placental density and visualizing spiral arteries. B-flow and spatio-temporal image correlation are pivotal, sensitive tools for quantifying spiral artery distensibility and volume flow in early pregnancy. These techniques enhance our understanding of placental vascular architecture and promise early diagnosis and intervention for pregnancies at risk. This paper emphasizes the importance of advanced imaging in prenatal care.

Review of shear wave elastography in placental function evaluations

Background: Ultrasound is key to evaluating placental function. However, traditional ultrasound examinations cannot evaluate the changes in the biomechanical properties of the placenta in vivo. As a non-invasive technique, shear wave elastography (SWE) can be used analyze the physiological and biomechanical properties of the placenta. Moreover, it can evaluate the pathological changes in early placental insufficiency in a more direct and sensitive manner.Objective: This study aimed to systematically introduce SWE in placental function evaluations.Materials and methods: The terms 'placenta', 'ultrasound', and 'elastography' were searched on Pubmed, Embase, and CNKI databases (Apr 2023); this review was limited to results including placental sonoelastography.Results: Twenty-six studies satisfied the inclusion criteria and were included in this review. Herein, we introduce the basic principle of SWE, analyze the factors affecting placental measurements, and summarize the prospects of clinical applications of SWE in the field of obstetrical diseases.Conclusion: The SWE technology demonstrates excellent clinical application value and research prospects in obstetrics, particularly in placental function evaluation, owing to its objective and repeatable quantitative operation.

Is prophylactic intraoperative abdominal aortic balloon occlusion beneficial in pregnancies with placenta previa and placenta accreta spectrum during cesarean section? A 5-year retrospective study

OBJECTIVE

To assess whether prophylactic intraoperative abdominal aortic balloon occlusion (IAABO) is indeed beneficial in pregnancies with placenta previa (PP) and placenta accreta spectrum (PAS) during cesarean section.

METHODS

A retrospective case-control study included 251 pregnancies with PP and/or PAS. All enrolled patients were divided into a PP/PAS group, a PP + PAS group, and an IAABO group. The demographic characteristics and maternal and neonatal outcomes were compared.

RESULTS

There was no significant difference in blood loss and transfusion between the IAABO group and the PP + PAS group (P > 0.05). However, blood loss and red blood cell and fresh frozen plasma transfusion in the above two groups were significantly higher than in the PP/PAS group (P < 0.05). More pregnancies in the IAABO group had to undergo uterine artery embolization (29.2%) or hysterectomy (20.8%), and this percentage was significantly higher than that in the other two groups (P < 0.001). All neonatal characteristics did not show differences between the IAABO group and PP + PAS group (P > 0.05). IAABO led to femoral artery thrombosis in three cases and minor postoperative renal injury in one case.

CONCLUSION

IAABO only acted as a less important supporting technique during cesarean section. There was no evidence suggesting that IAABO could significantly control the massive hemorrhage in pregnancies with PP and PAS during cesarean delivery.

Focal Placenta Accreta in a Congenitally Malformed Uterus: A Case Report

Placenta accreta is defined as an abnormal trophoblast invasion of part or all of the placenta into the myometrium of the uterine wall. It is a well-known cause of maternal morbidity and mortality. Here, we present a unique case of focal placenta accreta due to a bicornuate uterus and a history of septum resection. We also discuss its management and outcome. The patient underwent a classical cesarean section and reinforcement of the anterior and posterior uterine wall. The patient had a history of surgery for correction of uterine malformation, which may have resulted in an abnormal adherence of the placenta.

Animal models of the placenta accreta spectrum: current status and further perspectives

Placenta accreta spectrum disorder (PAS) is a kind of disease of placentation defined as abnormal trophoblast invasion of part or all of the placenta into the myometrium, even penetrating the uterus. Decidual deficiency, abnormal vascular remodeling in the maternal-fetal interface, and excessive invasion by extravillous trophoblast (EVT) cells contribute to its onset. However, the mechanisms and signaling pathways underlying such phenotypes are not fully understood, partly due to the lack of suitable experimental animal models. Appropriate animal models will facilitate the comprehensive and systematic elucidation of the pathogenesis of PAS. Due to the remarkably similar functional placental villous units and hemochorial placentation to humans, the current animal models of PAS are based on mice. There are various mouse models induced by uterine surgery to simulate different phenotypes of PAS, such as excessive invasion of EVT or immune disturbance at the maternal-fetal interface, which could define the pathological mechanism of PAS from the perspective of the "soil." Additionally, genetically modified mouse models could be used to study PAS, which is helpful to exploring the pathogenesis of PAS from the perspectives of both "soil" and "seed," respectively. This review details early placental development in mice, with a focus on the approaches of PAS modeling. Additionally, the strengths, limitations and the applicability of each strategy and further perspectives are summarized to provide the theoretical foundation for researchers to select appropriate animal models for various research purposes. This will help better determine the pathogenesis of PAS and even promote possible therapy.

Decreased AGGF1 facilitates the progression of placenta accreta spectrum via mediating the P53 signaling pathway under the regulation of miR-1296-5p

Placenta accreta spectrum (PAS), an emerging health issue worldwide, is the major causative factor of maternal morbidity and mortality in modern obstetrics, but limited studies have contributed to our understanding of the molecular biology of PAS. This study addressed the expression of AGGF1 and its specific role in the etiology of PAS. The expression of AGGF1 in the placentas of PAS was determined by quantitative PCR, western blot and immunohistochemistry. CCK-8 assay, wound healing assay, Transwell invasion assay and flow cytometry assay were performed to monitor cell proliferation, migration, invasion and apoptosis. The interaction between miR-1296-5p and AGGF1 was detected by dual-luciferase reporter gene assay. Results showed that the mRNA and protein expression of AGGF1 was decremented in placental tissues of PAS patients, compared with samples from women with placenta previa and normal pregnant women. Downregulation of AGGF1 promoted cell proliferation, invasion and migration, inhibited apoptosis in vitro, decreased P53 and Bax expression, and simultaneously increased Bcl-2 expression, whereas overexpression of AGGF1 had the opposite results. Additionally, the dual-luciferase assay confirmed AGGF1 as a target gene of miR-1296-5p in placental tissues of PAS. Particularly, miR-1296-5p fostered HTR8/SVneo cell proliferation, invasion, repression of apoptosis and regulation of P53 signaling axis by downregulating AGGF1 expression. Collectively, our study accentuated that downregulation of placental AGGF1 promoted trophoblast over-invasion by mediating the P53 signaling pathway under the regulation of miR-1296-5p.

Focal increta placentomegaly of the posterior nonscarred uterine wall and posterior asynclitic presentation

BACKGROUND

Fetal malpresentations and malpositions are more common in placenta previa and uterine cavity abnormalities.

AIM

To show successful management of focal increta placentomegaly and uterine preservation in primiparous woman.

CASE REPORT

We describe posterior low-lying focal increta placentomegaly verified during cesarean section, which is a possible risk factor for persistent posterior asynclitism and consequent mechanical dystocia. In addition to antifibrinolytics and uterotonics, hemostatic compression sutures of the posterior uterine wall were performed with an applied intrauterine balloon, and thus the uterus was preserved in primiparous woman as a definitive therapy.

CONCLUSION

Timely identified malplacentation as well as adequate medical and surgical measures taken by an experienced team of obstetricians and anesthesiologists can contribute to preservation of the uterus and thus the life of mother and neonate.

Diffusion and perfusion MRI parameters in the evaluation of placenta accreta spectrum disorders in patients with placenta previa

OBJECTIVES

To evaluate the placental function by monoexponential, biexponential, and diffusion kurtosis MR imaging (MRI) in patients with placenta previa.

METHODS

A total of 62 patients with placenta accreta spectrum (PAS) disorders and 11 patients with normal placentas were retrospectively enrolled, who underwent conventional diffusion-weighted imaging (DWI), intravoxel incoherent motion (IVIM), and diffusion kurtosis imaging (DKI). The apparent diffusion coefficient (ADC) and exponential ADC (eADC) from standard DWI, mean kurtosis (MK), and diffusion coefficient (MD) from DKI, and pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) from IVIM were measured and compared from the volumetric analysis.

RESULTS

Comparisons between patients with PAS disorders and patients with normal placentas demonstrated that MD mean, D mean, and D* mean values in patients with PAS disorders were significantly higher than those in patients with normal placentas (p < 0.05). Comparisons between patients with accreta, increta, and percreta, and patients with normal placentas showed that the D mean was significantly higher in patients with placenta increta and percreta than in patients with normal placentas (p < 0.05).

CONCLUSION

The accreta lesions in PAS disorders had deceased cellularity and increased blood movement. The alteration of placental cellularity was more prominent in placenta increta and percreta.

Correlation of clinical outcomes with the application of the 2020 consensus panel on histological classification for Placenta Accreta Spectrum (PAS)

OBJECTIVE

Placenta Accreta Spectrum (PAS) is a range of disorders characterized by placenta adherence to uterine myometrium. The pathologic nomenclature of PAS has varied. In 2020, a consensus panel proposed a system which would parallel the antenatal grading. Our goal was to assess if greater PAS associated morbidity correlated with increasing histopathological grades in this novel system for confirmed cases of PAS.

METHODS

A retrospective cohort analysis was performed of 125 singleton, non-anomalous pregnancies complicated by PAS at the University of Texas Health San Antonio Placenta Accreta program from 2005 to 2020. PAS cases confirmed after cesarean hysterectomy were classified by the new system and outcomes were analyzed including Kaplan-Meier analysis of gestational age at delivery by new pathology categorization.

RESULTS

Antepartum admission, length of stay and episodes of vaginal bleeding correlated with increasing grades of PAS. In addition, increased PAS grades were associated with deliveries at earlier gestational age and surgical outcomes including operative time, blood loss, ICU admission and post-operative length of stay.

CONCLUSIONS

The grading system proposed by the 2020 consensus panel correlates with antepartum, intra-operative and postoperative outcomes in cases of PAS cesarean hysterectomy and should be implemented for uniformity of reporting.

Maternal Serum Placental Protein-13 Levels in the Prediction of Pregnancies with Abnormal Invasive Placentation

OBJECTIVE

To evaluate whether placental protein-13 (PP-13) measured in the serum of pregnant women could predict abnormal invasive placentation (AIP) detected by color Doppler ultrasound (US) and magnetic resonance imaging scan in addition to the routine US scan during the third trimester.

MATERIALS AND METHODS

The prospective case-control study included patients subdivided in 2 groups: 42 pregnant women with a singleton pregnancy at 28-32 weeks of gestation with only suspected AIP, and 32 healthy pregnant women. The serum PP-13 levels were measured in both groups using an enzyme-linked immunosorbent assay (ELISA) method and statistically compared. The cases of AIP were confirmed by placental histopathological examination and/or the uterus removed by hysterectomy after elective caesarean section.

RESULTS

Serum PP-13 levels of pregnant women with AIP were significantly higher (p<0.001) than those of controls (650.32±387.33 vs. 231.43±94.33). Statistical analysis of maternal serum PP-13 levels above the threshold of 312 pg/ml (measured in the early third trimester) predicted AIP with 76.2% sensitivity and 75% specificity.

CONCLUSION

Maternal serum PP-13 may have a role in the pathophysiology of AIP owing to its high serum value in the AIP group. The maternal serum dosage of PP-13 levels could improve pregnancy management in those patients suspected of having AIP.

Prophylactic temporary abdominal aortic balloon occlusion for patients with pernicious placenta previa: a retrospective study

BACKGROUND

Pernicious placenta previa (PPP) can increase the risk of perioperative complications. During caesarean section in patients with adherent placenta, intraoperative blood loss, hysterectomy rate and transfusion could be reduced by interventional methods. Our study aimed to investigate the influence of maternal hemodynamics control and neonatal outcomes of prophylactic temporary abdominal aortic balloon (PTAAB) occlusion for patients with pernicious placenta previa.

METHODS

This was a retrospective study using data from the Peking University People's Hospital from January 2014 through January 2020. Clinical records of pregnant women undergoing cesarean section were collected. Patients were divided into two groups: treatment with PTAAB placement (group A) and no balloon placement (group B). Group A was further broken down into two groups: prophylactic placement (Group C) and balloon occlusion (group D).

RESULTS

Clinical records of 33 cases from 5205 pregnant women underwent cesarean section were collected. The number of groups A, B, C, and D were 17, 16, 5 and 12.We found that a significant difference in the post-operative uterine artery embolism rates between group A and group B (0% vs.31.3%, p = 0.018). There was a significant difference in the Apgar scores at first minute between group A and group B (8.94 ± 1.43 vs 9.81 ± 0.75,p = 0.037),and the same significant difference between two groups in the pre-operative central placenta previa (29.4% vs. 0%,p = 0.044), complete placenta previa (58.8% vs 18.8%, p = 0.032),placenta implantation (76.5% vs 31.3%, p = 0.015). We could also observe the significant difference in the amount of blood cell (2.80 ± 2.68vs.10.66 ± 11.97, p = 0.038) and blood plasma transfusion (280.00 ± 268.32 vs. 1033.33 ± 1098.20, p = 0.044) between group C and group D. The significant differences in the preoperative vaginal bleeding conditions (0% vs 75%, p = 0.009), the intraoperative application rates of vasopressors (0% vs. 58.3%, p = 0.044) and the postoperative ICU (intensive care unit) admission rates (0% vs. 58.3%, p = 0.044) were also kept.

CONCLUSIONS

PTAAB occlusion could be useful in reducing the rate of post-operative uterine artery embolism and the amount of transfusion, and be useful in coping with patients with preoperative vaginal bleeding conditions, so as to reduce the rate of intraoperative applications of vasopressors and the postoperative ICU (intensive care unit) admission. In PPP patients with placenta implantation, central placenta previa and complete placenta previa, we advocate the utilization of prophylactic temporary abdominal aortic balloon placement.

Menstruation: science and society

Women's health concerns are generally underrepresented in basic and translational research, but reproductive health in particular has been hampered by a lack of understanding of basic uterine and menstrual physiology. Menstrual health is an integral part of overall health because between menarche and menopause, most women menstruate. Yet for tens of millions of women around the world, menstruation regularly and often catastrophically disrupts their physical, mental, and social well-being. Enhancing our understanding of the underlying phenomena involved in menstruation, abnormal uterine bleeding, and other menstruation-related disorders will move us closer to the goal of personalized care. Furthermore, a deeper mechanistic understanding of menstruation-a fast, scarless healing process in healthy individuals-will likely yield insights into a myriad of other diseases involving regulation of vascular function locally and systemically. We also recognize that many women now delay pregnancy and that there is an increasing desire for fertility and uterine preservation. In September 2018, the Gynecologic Health and Disease Branch of the Eunice Kennedy Shriver National Institute of Child Health and Human Development convened a 2-day meeting, "Menstruation: Science and Society" with an aim to "identify gaps and opportunities in menstruation science and to raise awareness of the need for more research in this field." Experts in fields ranging from the evolutionary role of menstruation to basic endometrial biology (including omic analysis of the endometrium, stem cells and tissue engineering of the endometrium, endometrial microbiome, and abnormal uterine bleeding and fibroids) and translational medicine (imaging and sampling modalities, patient-focused analysis of menstrual disorders including abnormal uterine bleeding, smart technologies or applications and mobile health platforms) to societal challenges in health literacy and dissemination frameworks across different economic and cultural landscapes shared current state-of-the-art and future vision, incorporating the patient voice at the launch of the meeting. Here, we provide an enhanced meeting report with extensive up-to-date (as of submission) context, capturing the spectrum from how the basic processes of menstruation commence in response to progesterone withdrawal, through the role of tissue-resident and circulating stem and progenitor cells in monthly regeneration-and current gaps in knowledge on how dysregulation leads to abnormal uterine bleeding and other menstruation-related disorders such as adenomyosis, endometriosis, and fibroids-to the clinical challenges in diagnostics, treatment, and patient and societal education. We conclude with an overview of how the global agenda concerning menstruation, and specifically menstrual health and hygiene, are gaining momentum, ranging from increasing investment in addressing menstruation-related barriers facing girls in schools in low- to middle-income countries to the more recent "menstrual equity" and "period poverty" movements spreading across high-income countries.

Resuscitative Endovascular Balloon Occlusion of the Aorta and Concomitant Tranexamic Acid for Cesarean Hysterectomy Complicated by Common Femoral Artery Thrombosis: A Case Report

With increasing cesarean delivery rates, placenta accreta spectrum (PAS) disorders are occurring more frequently and represent a significant cause of peripartum hemorrhage. Different modalities have been explored to control blood loss during cesarean hysterectomies for PAS disorders, including administration of tranexamic acid (TXA) and balloon occlusion strategies. We present a case of a cesarean hysterectomy for a placenta percreta with the use of TXA and arterial balloon occlusion complicated by a lower extremity arterial thrombus requiring emergent thrombectomy. The outcome of this case suggests using caution with concomitant use of TXA and arterial balloon occlusion.

Maternal morbidity and mortality due to placenta accreta spectrum disorders

Placenta accreta spectrum (PAS) disorders are an increasing health problem in many parts of the world. They are an important risk factor for adverse maternal outcomes related to delivery, with a reported 18-fold increase in maternal morbidity. Profuse haemorrhage after attempting to remove the placenta is the most frequent complication and can lead to major maternal morbidity and ultimately to maternal death. Morbidity can also arise from the multiple procedures required to treat PAS disorders. Intensive care unit admission, mechanical ventilation, infection, and prolonged hospitalization are common in these patients. Long-term complications related to infertility and psychological disturbances can also occur and may have a strong and long-lasting impact on women's health. Antenatal diagnosis allows for appropriate scheduling of delivery and referral to a specialized centre and has been shown to reduce maternal morbidity and mortality.

The use of elastography in placental research - A literature review

INTRODUCTION

Ultrasound elastography is a technique used to quantify biomechanical changes that occur in parenchymal tissue with disease. Recent research has applied the technique to the placenta in order to investigate changes associated with uteroplacental dysfunction. We performed a literature review to summarise the current available information regarding this novel technique.

METHODS

Pubmed, CINAHL and Embase were searched using the terms "placenta", "ultrasound" and "elastography". Only full text studies written in English and limited to placental sonoelastography were included.

RESULTS

Twenty-eight studies met the inclusion criteria and were included in this review. Publications were divided into in vivo and ex vivo groups, and further categorised into four subgroups: normal pregnancy, pregnancy-induced hypertension and pre-eclampsia, fetal growth restriction and other pregnancy complications.

CONCLUSION

Ultrasound elastography can quantitatively assess biomechanical properties of the placenta in conditions where placental function is compromised.

AT-rich interactive domain 1A protein expression in normal and pathological pregnancies complicated by preeclampsia

AT-rich interactive domain 1A (ARID1A, as known as BAF250a) is a subunit of human switch/sucrose nonfermentable chromatin remodeling complex with tumour suppressor function. Mutations of Arid1a have been reported in many human cancers and low expression of this protein has been correlated to a poor prognosis outcome in patients affected by some types of cancer. Although there are many studies regarding ARID1A functions in cancer, little is known about its role in regulating cell differentiation and normal tissues homeostasis. Here, we investigate ARID1A expression in normal placental tissues of first and third trimester of gestation and in pathological placental tissues of pregnancy complicated by preeclampsia (PE) and intrauterine growth restriction (IUGR) to evaluate a possible role of this protein in trophoblast differentiation. We found that ARID1A was specifically expressed in villous and extravillous cytotrophoblastic cells in normal placentas whereas syncytiotrophoblast was negative. Interestingly, ARID1A was expressed in both cytotrophoblastic cells and syncytiotrophoblast in placentas affected by PE and PE-IUGR. Moreover, ARID1A was also present in syncitial knots of pathological placentas. The present results indicate that ARID1A is a good marker of poor trophoblast differentiation in these pathologies, because the significant high positive staining in syncytiotrophoblast nuclei may suggest a poor differentiation of this trophoblast layer due to the cytotrophoblast cells fusion with the syncytiotrophoblast overlaying before arresting their cell cycle.