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1.
Nat Rev Endocrinol ; 16(9): 479-494, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32601352

RESUMO

Pre-eclampsia and fetal growth restriction arise from disorders of placental development and have some shared mechanistic features. Initiation is often rooted in the maldevelopment of a maternal-placental blood supply capable of providing for the growth requirements of the fetus in later pregnancy, without exerting undue stress on maternal body systems. Here, we review normal development of a placental bed with a safe and adequate blood supply and a villous placenta-blood interface from which nutrients and oxygen can be extracted for the growing fetus. We consider disease mechanisms that are intrinsic to the maternal environment, the placenta or the interaction between the two. Systemic signalling from the endocrine placenta targets the maternal endothelium and multiple organs to adjust metabolism for an optimal pregnancy and later lactation. This signalling capacity is skewed when placental damage occurs and can deliver a dangerous pathogenic stimulus. We discuss the placental secretome including glycoproteins, microRNAs and extracellular vesicles as potential biomarkers of disease. Angiomodulatory mediators, currently the only effective biomarkers, are discussed alongside non-invasive imaging approaches to the prediction of disease risk. Identifying the signs of impending pathology early enough to intervene and ameliorate disease in later pregnancy remains a complex and challenging objective.


Assuntos
Retardo do Crescimento Fetal/fisiopatologia , Placentação/fisiologia , Pré-Eclâmpsia/fisiopatologia , Complicações na Gravidez/fisiopatologia , Biomarcadores , Decídua/fisiopatologia , Desenvolvimento Embrionário , Endométrio/fisiopatologia , Feminino , Desenvolvimento Fetal , Feto/irrigação sanguínea , Humanos , Placenta/irrigação sanguínea , Doenças Placentárias/fisiopatologia , Gravidez , Transdução de Sinais , Trofoblastos/fisiologia
2.
PLoS One ; 15(4): e0231461, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32298307

RESUMO

Although being the golden standard for intrapartum fetal surveillance, cardiotocography (CTG) has been shown to have poor specificity for detecting fetal acidosis. Non-invasive near-infrared-spectroscopy (NIRS) monitoring of placental oxygenation during labour has not been studied yet. The objective of the study was to determine whether changes in placental NIRS values during labour could identify intrapartum fetal hypoxia and resulting acidosis. We included 43 healthy women in active stage of labour at term. CTG and NIRS parameters in groups with vs. without neonatal umbilical artery pH ≤ 7.20 were compared using Mann-Whitney-U. Receiver-operating-characteristics (ROC) curves were used to estimate predictive value of CTG and NIRS parameters for neonatal pH ≤ 7.20. A computer-based statistical classification was also performed to further evaluate predictive values of CTG and NIRS for neonatal acidosis. Ten (23%) neonates were born with umbilical artery pH ≤ 7.20. Compared to group with pH > 7.20, fetal acidosis was associated with more episodes of placental NIRS deoxygenation (9 (range 2-37) vs. 2 (range 0-65); p<0.001), higher velocity of placental NIRS deoxygenation (2.31 (range 0-22) vs. 1 (range 0-49) %/s; p = 0.03), more decelerations on CTG (25 (range 3-91) vs. 10 (range 10-60); p = 0.02), and more prolonged decelerations on CTG (2 (range 0-4) vs. 1 (range 0-3); p = 0.04). Number of placental deoxygenations had the highest prognostic value for fetal/neonatal acidosis (area under the ROC curve 0.85 (95% confidence interval 0.70-0.99). Computer-based classification also identified number of placental deoxygenations as the most accurate classifier, with 25% false positive and 93% true positive rate in the training dataset, with 100% accuracy when applied to the testing dataset. Placental deoxygenations during labour measured by NIRS are associated with fetal/neonatal acidosis. Predictive value of placental NIRS for neonatal acidosis was superior to that of CTG.


Assuntos
Cardiotocografia/métodos , Feto/irrigação sanguínea , Trabalho de Parto , Placenta/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adolescente , Adulto , Feminino , Humanos , Trabalho de Parto/fisiologia , Pessoa de Meia-Idade , Oxigênio/metabolismo , Placenta/metabolismo , Gravidez , Adulto Jovem
3.
Subcell Biochem ; 94: 275-296, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32189304

RESUMO

During the past two decades, significant advances have been made in our understanding of the human fetal and embryonic hemoglobins made possible by the availability of pure, highly characterized materials and novel methods, e.g., nano gel filtration, to study their properties and to correct some misconceptions. For example, whereas the structures of the human adult, fetal, and embryonic hemoglobins are very similar, it has generally been assumed that functional differences between them are due to primary sequence effects. However, more recent studies indicate that the strengths of the interactions between their subunits are very different leading to changes in their oxygen binding properties compared to adult hemoglobin. Fetal hemoglobin in the oxy conformation is a much stronger tetramer than adult hemoglobin and dissociates to dimers 70-times less than adult hemoglobin. This property may form the basis for its protective effect against malaria. A major source of the increased strength of fetal hemoglobin resides within the A-helix of its gamma subunit as demonstrated in studies with the hybrid hemoglobin Felix and related hybrids. Re-activating fetal hemoglobin synthesis in vivo is currently a major focus of clinical efforts designed to treat sickle cell anemia since it inhibits the aggregation of sickle hemoglobin. The mechanisms for both the increased oxygen affinity of fetal hemoglobin and its decreased response to DPG have been clarified. Acetylated fetal hemoglobin, which makes up 10-20% of total fetal hemoglobin, has a significantly weakened tetramer structure suggesting a similar role for other kinds of protein acetylation. Embryonic hemoglobins have the weakest tetramer and dimer structures. In general, the progressively increasing strength of the subunit interfaces of the hemoglobin family during development from the embryonic to the fetal and ultimately to the adult types correlates with their temporal appearance and disappearance in vivo, i.e., ontogeny.


Assuntos
Embrião de Mamíferos/irrigação sanguínea , Hemoglobina Fetal/química , Hemoglobina Fetal/metabolismo , Oxigênio/metabolismo , Feto/irrigação sanguínea , Humanos
4.
PLoS One ; 15(2): e0226741, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32023263

RESUMO

AIMS: Fetuses affected by congenital heart defects (CHD) are considered to be at increased risk of fetal growth restriction and intrauterine demise. Whether these risks are a direct consequence of fetal CHD or a result of associated uteroplacental dysfunction is not evident from the data of recent studies. The aim of this study was to investigate the prevalence of uteroplacental dysfunction reflected by abnormal uterine artery Doppler indices and reduced fetal growth in CHD pregnancies. METHODS: This is a retrospective case-control study including singleton pregnancies referred for detailed fetal cardiac assessment subsequently diagnosed with or without CHD. Mid-trimester uterine artery Doppler assessment at 20-24 weeks as well as third trimester fetal biometry and arterial Doppler pulsatility indices (PI) were performed. All fetal biometry were converted into centiles and Doppler values to multiples of median (MoM) to adjust for physiological changes with gestation. RESULTS: The study included 811 pregnancies including 153 cases where the fetus was diagnosed with CHD. Mid-pregnancy uterine artery PI was significantly higher in women with fetal CHD compared to controls (0.90MoM vs 0.83MoM; p = 0.006). In the third trimester, median centiles for fetal head circumference (45.4 vs 57.07; p<0.001), abdominal circumference (51.17 vs 55.71; p = 0.014), estimated fetal weight (33.6 vs 56.7; p<0.001) and cerebroplacental ratio (CPR: 0.84MoM vs 0.95MoM; p<0.001) were significantly lower in fetuses with CHD compared to controls. The percentage of small for gestational age births <10th centile (24.0% vs 10.7%; <0.001) and low CPR <0.6MoM (11.7% vs 2.5%; p<0.001) were significantly higher in the fetal CHD cohort. CONCLUSIONS: Mid-pregnancy uterine artery resistance is increased and subsequent fetal biometry reduced in pregnancies with CHD fetuses. These findings suggest that fetal CHD are associated with uteroplacental dysfunction, secondary to impaired maternal uteroplacental perfusion resulting in relative fetal hypoxaemia and reduced fetal growth.


Assuntos
Feto/anormalidades , Feto/irrigação sanguínea , Cardiopatias Congênitas/fisiopatologia , Circulação Placentária , Adulto , Biometria , Feminino , Feto/diagnóstico por imagem , Cardiopatias Congênitas/diagnóstico por imagem , Humanos , Masculino , Gravidez , Ultrassonografia Doppler , Artéria Uterina/anormalidades , Artéria Uterina/diagnóstico por imagem
5.
J Endocrinol ; 244(1): 213-222, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31645018

RESUMO

Cerebral circulation is important in fetal brain development, and angiotensin II (Ang II) plays vital roles in regulation of adult cerebral circulation. However, functions of Ang II in fetal cerebral vasculature and influences of in utero hypoxia on Ang II-mediated fetal cerebral vascular responses are largely unknown. This study investigated the effects and mechanisms of in utero hypoxia on fetal middle cerebral arteries (MCA) via Ang II. Near-term ovine fetuses were exposed to in utero hypoxia, and fetal MCA responses to Ang II were tested for vascular tension, calcium transient, and molecular analysis. Ang II caused significant dose-dependent contraction in control fetal MCA. Ang II-induced MCA constriction was decreased significantly in hypoxic fetuses. Neither losartan (AT1R antagonist, 10-5 mol/L) nor PD123,319 (AT2R antagonist, 10-5 mol/L) altered Ang II-mediated contraction in fetal MCA. Phenylephrine-mediated constriction was also significantly weaker in hypoxic fetuses. Bay K8644 caused similar contractions between the two groups. Protein expression of L-type voltage-dependent calcium channels was unchanged. There were no differences in caffeine-mediated vascular tension or calcium transients. Contraction induced by PDBu (PKC agonist) was obviously weaker in hypoxic MCA. Protein expression of PKCß was reduced in the hypoxic compared with the control, along with no differences in phosphorylation levels. The results showed that fetal MCA was functionally responsive to Ang II near term. Intrauterine hypoxia reduced the vascular agonist-mediated contraction in fetal MCA, probably via decreasing PKCß and its phosphorylation, which might play protective effects on fetal cerebral circulation against transient hypoxia.


Assuntos
Angiotensina II/farmacologia , Feto/irrigação sanguínea , Hipóxia/embriologia , Proteína Quinase C beta/metabolismo , Contração Uterina/efeitos dos fármacos , Animais , Feminino , Artéria Cerebral Média/embriologia , Fosforilação/efeitos dos fármacos , Gravidez , Ovinos
6.
J Nippon Med Sch ; 86(4): 192-200, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31484880

RESUMO

Twin to twin transfusion syndrome (TTTS) is a major complication of monochorionic diamniotic (MD) twins, and its onset is known to be associated with placental vascular anastomoses and blood flow imbalance. In a typical case of TTTS, the recipient develops polyhydramnios, weight gain, cardiomegaly and hydrops fetalis in the uterus. In contrast, the donor develops oligohydramnios and intrauterine growth restriction. Recently, the significance of the renin-angiotensin-aldosterone system (RAAS) that transfers from the donor to the recipient has attracted interest in the fetal circulation of TTTS. The donor has decreased renal blood flow due to decreased circulating blood volume. For this reason, the secretion of RAAS hormones is augmented in the fetal kidneys of the donor. In TTTS, these RAAS hormones from the donor transfer to the recipient through the anastomosed vessels. In addition to excess preload, the recipient heart is exposed to excess afterload due to systemic vasoconstriction through RAAS hormones. Commonly occurring complications in the recipient include myocardial hypertrophy, atrioventricular valve regurgitation, and pulmonary valve stenosis or pulmonary atresia. Fetoscopic laser photocoagulation (FLP) has been introduced recently because neither mortality nor neurological morbidity have been satisfactorily improved with conventional treatment. FLP is a curative method that may improve the prognosis of TTTS. In Japan, this procedure has been performed frequently, and positive neurological outcomes have been achieved.


Assuntos
Transfusão Feto-Fetal , Feto/irrigação sanguínea , Volume Sanguíneo , Cardiomegalia/embriologia , Cardiomegalia/etiologia , Feminino , Doenças Fetais/etiologia , Doenças Fetais/fisiopatologia , Retardo do Crescimento Fetal/etiologia , Transfusão Feto-Fetal/diagnóstico por imagem , Transfusão Feto-Fetal/etiologia , Transfusão Feto-Fetal/patologia , Transfusão Feto-Fetal/terapia , Fetoscopia , Humanos , Terapia com Luz de Baixa Intensidade , Poli-Hidrâmnios/etiologia , Gravidez , Prognóstico , Estenose da Valva Pulmonar/embriologia , Estenose da Valva Pulmonar/etiologia , Circulação Renal , Sistema Renina-Angiotensina/fisiologia
8.
Surg Radiol Anat ; 41(11): 1325-1332, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31531712

RESUMO

PURPOSE: This study was conducted to demonstrate morphological pattern of the ulnar artery and to evaluate morphometrically its anatomical branching pattern in human fetuses. METHODS: Branching pattern of ulnar artery was evaluated on 121 upper limbs of dissected 63 of formalin-fixed fetus cadavers with gestational age ranging from 17 to 40 weeks. In order to obtain second and third trimester data, according to their gestational age, two groups were determined. RESULTS: In 79 of all 121 upper limbs (65%) ulnar artery gave anterior and posterior ulnar recurrent arteries as separate branches. In this study frequency of presence of a median artery was 46.28% among total examined 121 upper limbs. Median arteries originated from ulnar artery (3.57%) and from the common interosseous artery (53.57%) and anterior interosseous artery (42.85%). Mean distances of the measured parameters were demonstrated according to the gestational age and differences between group I (second trimester) and group II (third trimester). No statistical difference for groups was observed for gender and between right and left sides. CONCLUSIONS: Ulnar artery shows predictable patterns during second and third trimester of fetal period and can be suitable access effective alternative for diagnostic and therapeutic coronary interventions. Persistent median artery is important variation and knowledge of its incidence is important for diagnostic difficulties and also during awareness of its injury during surgical approaches.


Assuntos
Variação Anatômica , Feto/irrigação sanguínea , Antebraço/irrigação sanguínea , Artéria Ulnar/anatomia & histologia , Cadáver , Feminino , Idade Gestacional , Humanos , Masculino
9.
Comput Methods Programs Biomed ; 179: 104984, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31443859

RESUMO

BACKGROUND AND OBJECTIVE: Optimal development of placental vasculature is critical for fetal growth and health outcomes. Many studies characterizing the vascular structure of the fetal side of the placenta have utilized a range of two-dimensional and three-dimensional (3D) imaging techniques including X-ray micro-computed tomography (micro-CT) following perfusion of the vasculature with a radio-opaque compound. The CT approach has been used to study feto-placental vasculature in rodents and humans. Its inherent advantage is that it reveals the 3D structure in high resolution without destroying the sample. This permits both multiple scanning of the sample and follow-up histological investigations in the same sample. Nevertheless, the applicability of the approach is hampered both by the challenging segmentation of the vasculature and a lack of straightforward methodology to quantitate the feto-placental vascular network. This paper addresses these challenges. METHODS: An end-to-end methodology is presented for automatically segmenting the vasculature; obtaining a Strahler-ordered rooted-tree representation and extracting quantitative features from its nodes, segments and branches (including volume, length, tortuosity and branching angles). The methodology is demonstrated for rat and mouse placentas at the end of gestation (day 22 and day 18, respectively), perfused with Microfil® and imaged using two different micro-CT scanners. RESULTS: The 3D visualizations of the resulting vascular trees clearly demonstrate differences between the branching complexity, tree span and tree depth of the mouse and rat placentas. The quantitative characterizations of these trees include not only the fundamental features that have been utilized in other studies of feto-placental vasculature but also several additional features. Boxplots of several of these-tortuosity, number of side branches, number of offspring per branch and branch volume-computed at each Strahler order are presented and interpreted. Differences and similarities between the mouse and rat casts are readily detected. CONCLUSION: The proposed end-to-end methodology, and the implementation presented using a combination of Amira and Matlab, offers researchers in the field of placental vasculature characterization a straightforward and objective approach for quantifying micro-CT vascular datasets.


Assuntos
Feto/irrigação sanguínea , Placenta/irrigação sanguínea , Circulação Placentária/fisiologia , Algoritmos , Animais , Feminino , Desenvolvimento Fetal , Feto/diagnóstico por imagem , Humanos , Imageamento Tridimensional , Camundongos , Modelos Cardiovasculares , Placenta/diagnóstico por imagem , Placentação , Gravidez , Interpretação de Imagem Radiográfica Assistida por Computador/estatística & dados numéricos , Ratos , Microtomografia por Raio-X/estatística & dados numéricos
10.
Arkh Patol ; 81(4): 73-77, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31407722

RESUMO

The paper considers one of the types of intranatal fetal hypoxia - circulatory hypoxia. It discusses the issues of fetal head configuration during childbirth and the compensatory-adaptive mechanisms when the fetal head passes through the maternal parturient canal. The relationships and differences between circulatory hypoxia and birth trauma are investigated.


Assuntos
Hipóxia Fetal , Feto , Feto/irrigação sanguínea , Humanos
11.
Int J Gynaecol Obstet ; 147(1): 96-101, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31299100

RESUMO

OBJECTIVE: To elucidate classification of coiling of the umbilical cord around fetal neck (CUFN) by ultrasound and forming factors of entanglement angle of CUFN. METHODS: From January 2006 to December 2012, color Doppler ultrasonic was used to observe the blood flow vector of umbilical artery, and prospective descriptive observation was made for entanglement direction and type of 707 single fetuses taking prenatal examination in our hospital during the middle and late trimester of pregnancy and having umbilical cord echo around the neck. The relationship of position of fetus, position of placenta and entanglement direction of umbilical cord with the entanglement angle of umbilical cord is analyzed. RESULTS: Among the 707 fetuses, 634 had one circle of coiling, 43 had two circles of coiling, two had three circles of coiling, and 28 had CUFN. According to entanglement direction, 361 had entanglement from left to right and 318 had entanglement from right to left According to entanglement type, 305 were C-shaped type (43.14%), 85 were O-shaped type (12.02%), 289 were α-shaped type (40.88%), and 28 were L-shaped type (3.96%). CONCLUSION: Color Doppler ultrasound was used to detect the entanglement direction of umbilical cord and establish the five-type classification of umbilical cord around the neck, laying the foundation for the feasibility of establishing the normalization of diagnostic standard of umbilical cord around the neck.


Assuntos
Cordão Nucal/diagnóstico , Cordão Umbilical/diagnóstico por imagem , Adulto , Feminino , Feto/irrigação sanguínea , Humanos , Cordão Nucal/classificação , Cordão Nucal/patologia , Gravidez , Estudos Prospectivos , Ultrassonografia Doppler em Cores , Ultrassonografia Pré-Natal , Cordão Umbilical/irrigação sanguínea
12.
Theriogenology ; 138: 16-23, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31280181

RESUMO

The main purpose of examining multiparous species with real-time ultrasonography is to determine the gestational age and make various fetal measurements for early diagnosis of growth anomalies and sibling mismatches. This study investigated changes in fetometric measurements, obstetric Doppler indices and placental image analysis results based on gestational age and fetal location in fetuses located cranially and caudally between 16 and 24 days gestation in 22 healthy pregnant New Zealand rabbits. The first study group consisted of fetuses positioned at the cranial end (n = 22) while the second group consisted of fetuses positioned at the caudal end (n = 22) in each pregnancy. Fetal biparietal head diameter (BPD) and trunk diameter (TD) were measured, and mean grayness values (MGV) were determined from placental image analysis of each fetus. Using Doppler USG, the pulsatile (PI) and resistance (RI) indices of the uterine artery (UtA) and umbilical artery (UmA) were recorded. By the end of the study, BPD and TD values for cranial and caudal fetuses had significantly increased with gestational age (P < 0.001). The MGV values of caudal fetuses were significantly higher (except for the 16th day) (P < 0.05). The UtA PI value of the caudal fetuses was significantly higher (except for the 18th day) (P < 0.01). The UtA RI values of caudal fetuses were significantly higher than cranial ones on the 16 and 24th days (P < 0.05). The PI of the UmA increased until the 20th day before decreasing significantly in both study groups (P < 0.001). The UmA RI value decreased according to the gestational age in both groups (P < 0.001). It was significantly higher in the caudal fetuses on the 20th day (P < 0.05). The somatic rate of all fetuses peaked at the end of the second trimester, although caudal fetuses had higher fetometric values, and this location difference also affected placental echotexture. In both vessels of caudal fetuses, pulsatility and resistance values were higher. The 20th day of pregnancy was a threshold for the Doppler exam results. In conclusion, growth and metabolic status of fetuses located in different uterine locations in healthy pregnant New Zealand rabbits vary. Based on the these growth curves and hemodynamic data, more comprehensive studies of intrauterine life may be possible.


Assuntos
Feto/diagnóstico por imagem , Placenta/diagnóstico por imagem , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem , Artéria Uterina/diagnóstico por imagem , Útero/diagnóstico por imagem , Animais , Velocidade do Fluxo Sanguíneo , Feminino , Feto/irrigação sanguínea , Idade Gestacional , Hemodinâmica , Tamanho da Ninhada de Vivíparos , Placenta/irrigação sanguínea , Circulação Placentária/fisiologia , Gravidez , Fluxo Pulsátil , Coelhos , Ultrassonografia Doppler , Ultrassonografia Pré-Natal/métodos , Ultrassonografia Pré-Natal/veterinária , Artérias Umbilicais/fisiologia , Artéria Uterina/fisiologia , Útero/irrigação sanguínea
13.
Ultrasound Obstet Gynecol ; 54(4): 484-491, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31271475

RESUMO

BACKGROUND: Justification of prenatal screening for small-for-gestational-age (SGA) fetuses near term is based on, first, evidence that such fetuses/neonates are at increased risk of stillbirth and adverse perinatal outcome, and, second, the expectation that these risks can be reduced by medical interventions, such as early delivery. However, there are no randomized studies demonstrating that routine screening for SGA fetuses and appropriate interventions in the high-risk group can reduce adverse perinatal outcome. Before such meaningful studies can be undertaken, it is essential that the best approach for effective identification of SGA neonates is determined, and that the contribution of SGA neonates to the overall rate of adverse perinatal outcome is established. In a previous study of pregnancies undergoing routine ultrasound examination at 35 + 0 to 36 + 6 weeks' gestation, we found that, first, screening by estimated fetal weight (EFW) < 10th percentile provided poor prediction of SGA neonates and, second, prediction of > 85% of SGA neonates requires use of EFW < 40th percentile. OBJECTIVES: To examine the contribution of SGA fetuses to the overall rate of adverse perinatal outcome and, to propose a two-stage approach for prediction of a SGA neonate at routine ultrasound examination at 35 + 0 to 36 + 6 weeks' gestation. METHODS: This was a prospective study of 45 847 singleton pregnancies undergoing routine ultrasound examination at 35 + 0 to 36 + 6 weeks' gestation. First, we examined the relationship between birth-weight percentile and adverse perinatal outcome, defined as stillbirth, neonatal death or admission to the neonatal unit for ≥ 48 h. Second, we used a two-stage approach for prediction of a SGA neonate and adverse perinatal outcome; in the first stage, fetal biometry was used to distinguish between pregnancies at very low risk (EFW ≥ 40th percentile) and those at increased risk (EFW < 40th percentile) and, in the second stage, the pregnancies with EFW < 40th percentile were stratified into high-, intermediate- and low-risk groups based on the results of EFW and pulsatility index in the uterine arteries, umbilical artery and fetal middle cerebral artery. Different percentiles of EFW and Doppler indices were used to define each risk category, and the performance of screening for a SGA neonate and adverse perinatal outcome in pregnancies delivered at ≤ 2, 2.1-4 and > 4 weeks after assessment was determined. We propose that the high-risk group would require monitoring from initial assessment to delivery, the intermediate-risk group would require monitoring from 2 weeks after initial assessment to delivery, the low-risk group would require monitoring from 4 weeks after initial assessment to delivery, and the very low-risk group would not require any further reassessment. RESULTS: First, although in neonates with low birth weight (< 10th percentile) the risk of adverse perinatal outcome is increased, 84% of adverse perinatal events occur in the group with birth weight ≥ 10th percentile. Second, in screening by EFW < 10th percentile, the predictive performance for a SGA neonate is modest for those born at ≤ 2 weeks after assessment (83% and 69% for neonates with birth weight < 3rd and < 10th percentiles, respectively), but poor for those born at 2.1-4 weeks (65% and 45%, respectively) and > 4 weeks (40% and 30%, respectively) after assessment. Third, improved performance of screening, especially for those delivered at > 2 weeks after assessment, is potentially achieved by a proposed new approach for stratifying pregnancies into management groups based on findings of EFW and Doppler indices (prediction of birth weight < 3rd and < 10th percentiles for deliveries at ≤ 2, 2.1-4 and > 4 weeks after assessment: 89% and 75%, 83% and 74%, and 88% and 82%, respectively). Fourth, the predictive performance for adverse perinatal outcome of EFW < 10th percentile is very poor (26%, 9% and 5% for deliveries at ≤ 2, 2.1-4 and > 4 weeks after assessment, respectively) and this is improved by the proposed new approach (31%, 22% and 29%, respectively). CONCLUSIONS: This study presents an approach for stratifying pregnancies undergoing routine ultrasound examination at 35 + 0 to 36 + 6 weeks' gestation into four management groups based on findings of EFW and Doppler indices. This approach potentially has a higher predictive performance for a SGA neonate and adverse perinatal outcome than that of screening by EFW < 10th percentile. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Feto/diagnóstico por imagem , Recém-Nascido Pequeno para a Idade Gestacional/sangue , Diagnóstico Pré-Natal/métodos , Ultrassonografia Pré-Natal/métodos , Adulto , Peso ao Nascer/fisiologia , Feminino , Peso Fetal/fisiologia , Feto/irrigação sanguínea , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Morte Perinatal/etiologia , Morte Perinatal/prevenção & controle , Valor Preditivo dos Testes , Gravidez , Terceiro Trimestre da Gravidez , Cuidado Pré-Natal/normas , Estudos Prospectivos , Fatores de Risco , Natimorto/epidemiologia , Ultrassonografia Doppler , Ultrassonografia Pré-Natal/estatística & dados numéricos , Artérias Umbilicais/diagnóstico por imagem , Artéria Uterina/diagnóstico por imagem
14.
J Obstet Gynaecol Res ; 45(9): 1936-1940, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31237393

RESUMO

Fetal intra-abdominal umbilical vein varix is an uncommon antenatal finding defined as focal dilatation of umbilical vein >9 mm or more than two standard deviations above the mean for the gestational age. We report the case of a 28-year-old gravida 2 diabetic lady, who presented at 35 weeks of gestation, whose antenatal ultrasonography showed a cystic lesion of size 4 × 3.8 cm showing turbulent venous flow in the fetal abdomen in continuity with the umbilical vein, diagnosed as umbilical vein varix without any other anomaly. Postnatal ultrasonography showed size reduction and thrombosis of varix. Isolated umbilical vein varix has a favorable outcome, whereas those associated with other structural anomalies have a variable prognosis. This case was reported because of the unusually large size of varix with a good outcome and also to stress the importance of detailed sonography and close fetal monitoring in the presence of umbilical vein varix.


Assuntos
Feto/irrigação sanguínea , Ultrassonografia Pré-Natal , Veias Umbilicais/irrigação sanguínea , Varizes/diagnóstico por imagem , Adulto , Feminino , Feto/embriologia , Idade Gestacional , Humanos , Gravidez , Veias Umbilicais/embriologia , Varizes/embriologia
15.
J Gynecol Obstet Hum Reprod ; 48(7): 495-499, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31176048

RESUMO

OBJECTIVE: It's proposed that oligohydramnios is caused by decreased renal perfusion due to redistribution of fetal blood at fetal growth restriction. Isolated oligohydramnios refers to the presence of oligohydramnios without fetal structural and chromosomal abnormalities, without fetal growth restriction, without intrauterine infection, and in the absence of known maternal disease. It's unknown whether the redistribution or decreased renal perfusion cause isolated oligohydramnios. The aim of the study was to evaluate fetal renal artery Doppler blood velocimetry and cerebro-placental ratio (CPR) among women with isolated oligohydramnios between 25-40 weeks of gestational age. STUDY DESIGN: The middle cerebral artery, umbilical artery and, renal artery pulsatility index (PI) values were measured in 45 fetuses with isolated oligohydramnios and 65 fetuses with normal amniotic fluid. Oligohydramnios was defined as deepest vertical amniotic fluid being measured lower than 1cm. The CPR (middle cerebral artery PI/umbilical artery PI) and renal artery PI values were expressed as multiples of the normal median (MoM) and were compared between the two groups. RESULTS: There was no difference in MoM of CPR PI (p=0.167) and MoM of renal artery PI values (right p=0.253, left p=0.353) between the groups. CONCLUSION: The renal artery Doppler velocimetry and CPR were not significantly different in the women with isolated oligohydramnios, compared to the women with normal amniotic fluid.


Assuntos
Encéfalo/irrigação sanguínea , Feto/irrigação sanguínea , Rim/irrigação sanguínea , Oligo-Hidrâmnio/fisiopatologia , Circulação Placentária/fisiologia , Circulação Renal/fisiologia , Líquido Amniótico/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Estudos de Casos e Controles , Feminino , Feto/diagnóstico por imagem , Humanos , Recém-Nascido , Rim/diagnóstico por imagem , Rim/embriologia , Masculino , Artéria Cerebral Média/fisiopatologia , Oligo-Hidrâmnio/diagnóstico , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Fluxo Pulsátil , Artéria Renal/fisiologia , Ultrassonografia Doppler em Cores , Ultrassonografia Pré-Natal
16.
Arch Gynecol Obstet ; 300(3): 589-600, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31201538

RESUMO

PURPOSE: Elective cesarean section (CS) was related to long-term adverse health effects in the offspring, but little is known about underlying mechanisms. Our study investigates the metabolic changes in both maternal and cord blood associated with CS in comparison to vaginal delivery (VD) to explore potential causal pathways. METHODS: Samples obtained from PREOBE study participants were subjected to LC-MS/MS-targeted metabolomics comprising > 200 metabolites. RESULTS: Elective CS showed an impact on both maternal and cord blood metabolomes. In maternal blood, the CS group showed lower levels of phospholipids (PL), principally ether-linked phosphatidylcholines (aaPC), pyruvic acid, branched chain keto-acids (BCKA), and other gluconeogenic substrates, but since the CS group showed different HDL levels in comparison to the VD group, we could not exclude contribution of the latter in the findings. In cord blood, the most remarkable finding in the CS group was the high levels of Cys; conversely, the lower levels of non-esterified fatty acids (NEFA), some tricarboxylic acid (TCA) cycle metabolites, gluconeogenic substrates, markers of ß-oxidation, and the sum of hexoses were lower in CS-born babies in addition to tendentially lower levels of PL. CONCLUSIONS: We speculate that lower levels of maternal and fetal corticosteroids in CS, due to less stressful condition, cause metabolic perturbations at birth initiating future negative health outcomes. This further supports the early programming hypothesis.


Assuntos
Cesárea/efeitos adversos , Parto Obstétrico/estatística & dados numéricos , Sangue Fetal/metabolismo , Feto/irrigação sanguínea , Lipoproteínas/sangue , Metabolômica , Adulto , Cesárea/estatística & dados numéricos , Cromatografia Líquida , Parto Obstétrico/métodos , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos não Esterificados/metabolismo , Feminino , Humanos , Lipoproteínas HDL/sangue , Parto , Fosfolipídeos/sangue , Gravidez , Cuidado Pré-Natal , Espanha , Espectrometria de Massas em Tandem
17.
Int. j. morphol ; 37(2): 752-756, June 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1002289

RESUMO

In the prenatal period, the three types of connections between the portal sinus and main portal vein have been published in the literature: T, X and H-shaped. The T type is the most frequent in the literature, and the aim of our study is to define the percentage of the connection types during the prenatal period in our population. In this prospective study, 237 women between 20 and 38 weeks of pregnancy without a foetal anomaly or pregnancy-related complications were included, and the precordial veins of the foetuses were examined using a wide-band color Doppler technique. The types of connections were determined by two specialists according to the shape of the colour coded vessels in Doppler examinations. The criteria of Czubalski & Aleksandrowicz (2000) were used. All of the connection types in patients were confirmed using video clips and were stored in the picture archiving and communication system. In 237 patients, the types of connection were determined by the first specialist as 189 foetuses (79.7 %) with the X-shaped or side-to-side connection, 16 foetuses (6.8 %) with the T-shaped or end-to-side type and 32 foetuses (13.5 %) with the H-shaped or parallel-coursed vessels connected with a short segment. The most common types of connections between the portal sinus and main portal vein in foetuses are X shaped or side-to-side, which is contrary to previous studies.


En el período prenatal, se han publicado en la literatura los tres tipos de conexiones entre el seno portal y la vena porta principal: en forma de T, X y H. El tipo T es el más frecuente, y el objetivo de nuestro estudio fue definir el porcentaje de tipos de conexión durante el período prenatal en nuestra población. En este estudio prospectivo, se incluyeron 237 mujeres entre 20 y 38 semanas de embarazo, sin anomalías fetales o complicaciones relacionadas con el embarazo, y se examinaron las venas precordiales de los fetos utilizando una técnica Doppler de banda ancha. Los tipos de conexiones fueron determinados por dos especialistas según la forma de los vasos codificados por color en los exámenes Doppler. Se utilizaron los criterios del estudio de Czubalski & Aleksandrowicz. Todos los tipos de conexión en los pacientes se confirmaron mediante videoclips y se almacenaron en el sistema de comunicación y en archivo de imágenes. En 237 pacientes, el primer especialista determinó en 189 fetos (79,7 %) la conexión en forma de X o de lado a lado; en 16 fetos (6,8 %) la forma de T o Tipo de extremo a lado; y en 32 fetos (13,5 %) los vasos en forma de H o paralelos, conectados con un segmento corto. Los tipos más comunes de conexiones entre el seno portal y la vena porta principal en los fetos son en forma de X o de lado a lado, lo que es contrario a estudios anteriores.


Assuntos
Humanos , Masculino , Feminino , Gravidez , Adolescente , Adulto , Veia Porta/anatomia & histologia , Veias Umbilicais/anatomia & histologia , Feto/irrigação sanguínea , Veia Porta/embriologia , Veia Porta/diagnóstico por imagem , Veias Umbilicais/embriologia , Veias Umbilicais/diagnóstico por imagem , Estudos Prospectivos , Ultrassonografia Doppler em Cores , Variação Anatômica
18.
Artigo em Inglês | MEDLINE | ID: mdl-31067632

RESUMO

Prenatal alcohol exposure results in an array of developmental abnormalities known as fetal alcohol spectrum disorders (FASDs). Despite the high prevalence of FASDs, therapeutic interventions against accidental or intended exposure of developing fetuses to alcohol are limited. This review outlines current knowledge about mitochondria in cerebral blood vessels as a potential target for anti-FASDs intervention. First, it describes the multifaceted role of mitochondria in maintaining the cerebral artery diameter as shown in adult tissue. Second, current literature on alcohol-driven damage of mitochondrial morphology and function in several fetal tissues, including liver, heart, and brain is summarized. The functional consequences of alcohol exposure in these organs include morphological enlargement of mitochondria, increased oxidative stress, and alteration of cellular respiration. These studies point to a tissue-specific effect of alcohol on mitochondrial function and a particular vulnerability of fetal mitochondria to alcohol exposure when compared to adult counterparts. Third, recent work from our group describing persistent changes in fetal baboon cerebral artery proteome following three episodes of prenatal alcohol exposure is reviewed. In conclusion, the consequences of prenatal alcohol exposure on cerebral artery mitochondria constitute an open field of investigation and, eventually, a point of therapeutic intervention against FASDs.


Assuntos
Artérias Cerebrais/efeitos dos fármacos , Etanol/toxicidade , Transtornos do Espectro Alcoólico Fetal/etiologia , Feto/irrigação sanguínea , Mitocôndrias/efeitos dos fármacos , Animais , Artérias Cerebrais/fisiologia , Feminino , Desenvolvimento Fetal , Humanos , Troca Materno-Fetal , Mitocôndrias/fisiologia , Gravidez
19.
Ginekol Pol ; 90(4): 189-194, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31059111

RESUMO

OBJECTIVES: The aim of the study was to analyze the changes in cardiac function and myocardial contractility of donor and recipient fetuses with twin-to-twin transfusion syndrome (TTTS) subjected to selective laser photocoagulation of the communicating vessels (SLPCV), between and after the procedure. Finally, we verified if fetuses with Quintero's stage I TTTS presented with early impairment of myocardial contractility. MATERIAL AND METHODS: We selected 77 consecutive women with twin pregnancies, whose both fetuses survived at least seven days post-SLPCV. Myocardial contractility of both fetuses was evaluated ultrasonographically, and their myocardial performance indices (Tei-Index values) and shortening fractions (SF) were determined. RESULTS: In donor fetuses, the Tei-Index values for both right and left ventricle remained within the respective reference ranges both before the procedure and during a 7-day follow-up. A significant change in shortening fraction values for the left ventricle in recipient fetuses and the right ventricle of in the donors was observed during a 7-day follow-up. CONCLUSIONS: Comparison of the cardiac parameters of donors and recipients revealed significant differences in Tei-indices during the entire follow-up period. The group with Quintero's I stage TTTS included 74% of recipient fetuses with abnormal Tei-Index values for the right ventricle (mean 0.53).


Assuntos
Coração Fetal , Transfusão Feto-Fetal , Feto , Feminino , Coração Fetal/diagnóstico por imagem , Coração Fetal/fisiologia , Transfusão Feto-Fetal/fisiopatologia , Transfusão Feto-Fetal/cirurgia , Feto/irrigação sanguínea , Feto/diagnóstico por imagem , Feto/fisiopatologia , Feto/cirurgia , Seguimentos , Humanos , Fotocoagulação a Laser , Gravidez , Gravidez de Gêmeos , Ultrassonografia Pré-Natal
20.
Radiographics ; 39(3): 893-910, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31059392

RESUMO

Doppler US provides a unique window to the fetoplacental circulation, allowing assessment of fetal well-being. Doppler US of the umbilical artery is an integral component of managing the fetus with growth restriction; and Doppler US of the middle cerebral artery, as a noninvasive means of detecting fetal anemia, has revolutionized the management of pregnancies complicated by alloimmunization. Serial use of amniocentesis, with its attendant risks, has been replaced by serial Doppler US examinations. Invasive procedures are now reserved for the treatment of anemia with intrauterine transfusion. Technique is critical to obtain the best waveforms for ease of shape assessment, velocity measurement, and calculation of various ratios. In this article, the safety of Doppler US is reviewed, the fetal circulation is described, and the role of Doppler US is demonstrated in first-trimester screening and in the evaluation of growth restriction, anemia, and other causes of fetal compromise in the second and third trimesters. Sampling technique is explained, and normal and abnormal waveforms are illustrated for the ductus venosus, umbilical artery, umbilical vein, middle cerebral artery, and uterine artery. Some examples of clinical cases are provided to illustrate how the results are used in clinical practice. Clinical examples of velamentous insertion and vasa previa are also provided to aid the practicing radiologist with recognition of these entities. In particular, vasa previa is considered a critical finding; it alters pregnancy management, requiring hospital admission, administration of steroid therapy, and planned early cesarean delivery. ©RSNA, 2019.


Assuntos
Feto/diagnóstico por imagem , Complicações na Gravidez/diagnóstico por imagem , Ultrassonografia Doppler/métodos , Ultrassonografia Pré-Natal/métodos , Adulto , Feminino , Doenças Fetais/diagnóstico por imagem , Feto/irrigação sanguínea , Humanos , Artéria Cerebral Média/diagnóstico por imagem , Circulação Placentária , Gravidez , Trimestres da Gravidez , Artérias Umbilicais/diagnóstico por imagem
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