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1.
Bioethics ; 38(5): 419-424, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38652592

RESUMO

Parthenogenesis is a form of asexual reproduction in which a gamete (ovum or sperm) develops without being fertilized. Tomer Jordi Chaffer uses parthenogenesis to challenge Don Marquis' future-like-ours (FLO) argument against abortion. According to Marquis, (1) what makes it morally wrong to kill us is that it would deprive us of a possible future that we might come to value-a future "like ours" (FLO) and (2) human fetuses are numerically identical to any adult human organism they may develop into, and thus have a FLO. Chaffer contends that if human ova are capable of parthenogenesis, then they would have a FLO, which contraception may deprive them of, but contends this is absurd. Bruce P. Blackshaw challenges Chaffer, contending sexually fertilized embryos are not identical to unfertilized ovum, but this would yield a more absurd implication, that fertilization deprives an ovum of a FLO! Here I show Marquis' account of identity rules out both Chaffer's and Blackshaw's accounts.


Assuntos
Partenogênese , Humanos , Feminino , Gravidez , Masculino , Aborto Induzido/ética , Valor da Vida , Fertilização , Óvulo , Feto
2.
Radiat Prot Dosimetry ; 200(6): 580-587, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38486458

RESUMO

This study aimed to assess fetal radiation exposure in pregnant women undergoing computed tomography (CT) and rotational angiography (RA) examinations for the diagnosis of pelvic trauma. In addition, this study aimed to compare the dose distributions between the two examinations. Surface and average fetal doses were estimated during CT and RA examinations using a pregnant phantom model and real-time dosemeters. The pregnant model phantom was constructed using an anthropomorphic phantom, and a custom-made abdominal phantom was used to simulate pregnancy. The total average fetal dose received by pregnant women from both CT scans (plain, arterial and equilibrium phases) and a single RA examination was ~60 mGy. Because unnecessary repetition of radiographic examinations, such as CT or conventional 2D angiography can increase the radiation risk, the irradiation range should be limited, if necessary, to reduce overall radiation exposure.


Assuntos
Feto , Pelve , Imagens de Fantasmas , Doses de Radiação , Exposição à Radiação , Tomografia Computadorizada por Raios X , Humanos , Feminino , Gravidez , Exposição à Radiação/análise , Feto/efeitos da radiação , Feto/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Pelve/diagnóstico por imagem , Pelve/efeitos da radiação , Angiografia/métodos , Adulto
3.
Neuroimage ; 290: 120560, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431181

RESUMO

Brain extraction and image quality assessment are two fundamental steps in fetal brain magnetic resonance imaging (MRI) 3D reconstruction and quantification. However, the randomness of fetal position and orientation, the variability of fetal brain morphology, maternal organs around the fetus, and the scarcity of data samples, all add excessive noise and impose a great challenge to automated brain extraction and quality assessment of fetal MRI slices. Conventionally, brain extraction and quality assessment are typically performed independently. However, both of them focus on the brain image representation, so they can be jointly optimized to ensure the network learns more effective features and avoid overfitting. To this end, we propose a novel two-stage dual-task deep learning framework with a brain localization stage and a dual-task stage for joint brain extraction and quality assessment of fetal MRI slices. Specifically, the dual-task module compactly contains a feature extraction module, a quality assessment head and a segmentation head with feature fusion for simultaneous brain extraction and quality assessment. Besides, a transformer architecture is introduced into the feature extraction module and the segmentation head. We utilize a multi-step training strategy to guarantee a stable and successful training of all modules. Finally, we validate our method by a 5-fold cross-validation and ablation study on a dataset with fetal brain MRI slices in different qualities, and perform a cross-dataset validation in addition. Experiments show that the proposed framework achieves very promising performance.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Humanos , Gravidez , Feminino , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Cabeça , Feto/diagnóstico por imagem
4.
PLoS One ; 19(2): e0298060, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38359058

RESUMO

Fetal growth restriction (FGR) is one of the leading causes of perinatal morbidity and mortality. Many studies have reported an association between FGR and fetal Doppler indices focusing on umbilical artery (UA), middle cerebral artery (MCA), and ductus venosus (DV). The uteroplacental-fetal circulation which affects the fetal growth consists of not only UA, MCA, and DV, but also umbilical vein (UV), placenta and uterus itself. Nevertheless, there is a paucity of large-scale cohort studies that have assessed the association between UV, uterine wall, and placental thickness with perinatal outcomes in FGR, in conjunction with all components of the uteroplacental-fetal circulation. Therefore, this multicenter study will evaluate the association among UV absolute flow, placental thickness, and uterine wall thickness and adverse perinatal outcome in FGR fetuses. This multicenter retrospective cohort study will include singleton pregnant women who undergo at least one routine fetal ultrasound scan during routine antepartum care. Pregnant women with fetuses having structural or chromosomal abnormalities will be excluded. The U-AID indices (UtA, UA, MCA, and UV flow, placental and uterine wall thickness, and estimated fetal body weight) will be measured during each trimester of pregnancy. The study population will be divided into two groups: (1) FGR group (pregnant women with FGR fetuses) and (2) control group (those with normal growth fetus). We will assess the association between U-AID indices and adverse perinatal outcomes in the FGR group and the difference in U-AID indices between the two groups.


Assuntos
Feto , Placenta , Feminino , Humanos , Gravidez , Biometria , Estudos de Coortes , Desenvolvimento Fetal , Retardo do Crescimento Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/epidemiologia , Feto/diagnóstico por imagem , Feto/irrigação sanguínea , Idade Gestacional , Estudos Multicêntricos como Assunto , Placenta/diagnóstico por imagem , Estudos Retrospectivos , Ultrassonografia Doppler , Ultrassonografia Pré-Natal/métodos , Artérias Umbilicais/diagnóstico por imagem
5.
J Anat ; 244(6): 1093-1101, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38267217

RESUMO

The etiology of sirenomelia is currently unknown. Data are limited in comparing external and internal abnormalities using modern imaging technologies and molecular genetic analysis. The purpose of the current study was designed to compare external and internal anatomical defects in two cases of sirenomelia and Potter's sequence. Considered rare, Potter's sequence is a fetal disorder with characteristic features of bilateral renal agenesis, obstructive uropathy, atypical facial appearance, and limb malformations. The internal and external malformations of two term fetuses with sirenomelia and Potter's sequence were compared using assessment of external features, radiography and MRI on internal structures, and molecular genetic studies on sex determination. Data reveal that both fetuses were male and manifested with an overlapping but distinct spectrum of abnormalities. Principal differences were noted in the development of the ears, brain, urogenital system, lower limbs, pelvis, and vertebral column. Defects of the axial mesoderm are likely to underlie the abnormalities seen in both fetuses. The first one, which had only caudal defects, was found to have a spectrum of abnormalities most similar to those associated with more severe forms of the small pelvic outlet syndrome, although the structure and orientation of the sacrum and iliae were different from previously reported cases. The other had both caudal and cranial defects, and was most similar to those described in the axial mesodermal dysplasia syndrome. Defects associated with sirenomelia can be evaluated with standard gross anatomy examination, radiology, MRI, and modified PCR techniques to determine anatomical abnormalities and the sex of preserved specimens, respectively. Evidence indicated that sirenomelia could be developed via various etiologies.


Assuntos
Ectromelia , Humanos , Masculino , Ectromelia/genética , Ectromelia/diagnóstico por imagem , Ectromelia/patologia , Feminino , Imageamento por Ressonância Magnética , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/diagnóstico por imagem , Gravidez , Feto/anormalidades , Feto/diagnóstico por imagem
6.
Lancet ; 403(10426): 545-553, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38219773

RESUMO

BACKGROUND: The cerebroplacental ratio is associated with perinatal mortality and morbidity, but it is unknown whether routine measurement improves pregnancy outcomes. We aimed to evaluate whether the addition of cerebroplacental ratio measurement to the standard ultrasound growth assessment near term reduces perinatal mortality and severe neonatal morbidity, compared with growth assessment alone. METHODS: RATIO37 was a randomised, open-label, multicentre, pragmatic trial, conducted in low-risk pregnant women, recruited from nine hospitals over six countries. The eligibility criteria were designed to be broad; participants were required to be 18 years or older, with an ultrasound-dated confirmed singleton pregnancy in the first trimester, an alive fetus with no congenital malformations at the routine second-trimester ultrasound, an absence of adverse medical or obstetric history, and the capacity to give informed consent. Women were randomly assigned in a 1:1 ratio (block size 100) using a web-based system to either the concealed group or revealed group. In the revealed group, the cerebroplacental ratio value was known by clinicians, and if below the fifth centile, a planned delivery after 37 weeks was recommended. In the concealed group, women and clinicians were blinded to the cerebroplacental ratio value. All participants underwent ultrasound at 36 + 0 to 37 + 6 weeks of gestation with growth assessment and Doppler evaluation. In both groups, planned delivery was recommended when the estimated fetal weight was below the tenth centile. The primary outcome was perinatal mortality from 24 weeks' gestation to infant discharge. The study is registered at ClinicalTrials.gov (NCT02907242) and is now closed. FINDINGS: Between July 29, 2016, and Aug 3, 2021, we enrolled 11 214 women, of whom 9492 (84·6%) completed the trial and were eligible for analysis (4774 in the concealed group and 4718 in the revealed group). Perinatal mortality occurred in 13 (0·3%) of 4774 pregnancies in the concealed group and 13 (0·3%) of 4718 in the revealed group (OR 1·45 [95% CI 0·76-2·76]; p=0·262). Overall, severe neonatal morbidity occurred in 35 (0·73%) newborns in the concealed group and 18 (0·38%) in the revealed group (OR 0·58 [95% CI 0·40-0·83]; p=0·003). Severe neurological morbidity occurred in 13 (0·27%) newborns in the concealed group and nine (0·19%) in the revealed group (OR 0·56 [95% CI 0·25-1·24]; p=0·153). Severe non-neurological morbidity occurred in 23 (0·48%) newborns in the concealed group and nine (0·19%) in the revealed group (0·58 [95% CI 0·39-0·87]; p=0·009). Maternal adverse events were not collected. INTERPRETATION: Planned delivery at term based on ultrasound fetal growth assessment and cerebroplacental ratio at term was not followed by a reduction of perinatal mortality although significantly reduced severe neonatal morbidity compared with fetal growth assessment alone. FUNDING: La Caixa foundation, Cerebra Foundation for the Brain Injured Child, Agència per la Gestió d'Ajuts Universitaris i de Recerca, and Instituto de Salud Carlos III.


Assuntos
Morte Perinatal , Ultrassonografia Pré-Natal , Feminino , Humanos , Recém-Nascido , Gravidez , Desenvolvimento Fetal , Feto , Resultado da Gravidez/epidemiologia , Cuidado Pré-Natal
7.
Vet Med Sci ; 10(1): e1343, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38227705

RESUMO

BACKGROUND: Both male and female food animals are slaughtered for meat. Some cows, ewes and does  slaughtered are found with viable foetuses resulting in foetal wastage and loss of future replacement stock. Foetal wastage accounts for about 20%-25% of the decline in livestock numbers in sub-Saharan Africa. Slaughter of pregnant cows, ewes and does results in economic losses and threatens food security with consequent decrease in available animal proteins to the fast growing human population. Protein requirement for healthy human development is inadequate in most developing countries including Uganda. The prevalence and economic losses associated with foetal wastage were assessed in an abattoir. OBJECTIVES: The study was cnducted to assess the prevalence of feotal wastage at the study abattoir and estimate the associated economic losses. METHODS: The researchers supported by abattoir resident meat inspectors examined all slaughtered female animals during the study period. Gravid uteri obtained from slaughtered animals after dressing of carcasses were eviscerated using a sharp knife across the long axis to recover foetuses. The crown rump lengths (CRLs) of the recovered foetuses were measured using a tape measure, weighed on a scale and categorised into first, second and third trimesters. Prevalence of pregnant animals slaughtered was determined by calculating the percentage of pregnant animals over the total number of female animals slaughtered. Economic losses were estimated based on the monetary losses at birth, weaning, maturity, and carcass loss at weaning and maturity. RESULTS: The aggregate slaughters were bovine 604 (73.6%), caprine 169 (20.6%) and ovine 48 (5.9%). The overall prevalence of foetal wastage was 21.9%. The aggregate prevalence of foetal wastage by species include 160 (88.9%) cows, 8 (4.4%) heifers, 4 (2.2%) does and 8 (4.4%) ewes. Foetal wastage of cows by trimester included 62 (38.8%), 26 (16.25%) and 72 (45.0%) in first, second and third trimesters, respectively, translating into loss of US$13,055. Foetal wastage was high and the associated economic losses were substantial which undermines sustainability of the national herd. Farmers should be sensitised about the economic losses and long-term impact associated with foetal wastage and dissuaded from this practice. A policy is needed to deter farmers from selling pregnant animals for slaughter. CONCLUSIONS: A total of 168 bovine, 8 caprine and 12 ovine foetuses were wasted within 60 days study period. These foetal wastages translated to US$ 13,224 monetary losses at birth, US$ 31,849 monetary loss at weaning and US$ 57,0896 monetary loss at maturity.


Assuntos
Matadouros , Cabras , Gravidez , Humanos , Animais , Feminino , Ovinos , Bovinos , Masculino , Prevalência , Feto , Carneiro Doméstico
8.
Arch Gynecol Obstet ; 309(1): 79-92, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37072584

RESUMO

PURPOSE: Fetal growth restriction (FGR) management and delivery planning is based on a multimodal approach. This meta-analysis aimed to evaluate the prognostic accuracies of the aortic isthmus Doppler to predict adverse perinatal outcomes in singleton pregnancies with FGR. METHODS: PubMed, EMBASE, the Cochrane Library, ClinicalTrials.gov and Google scholar were searched from inception to May 2021, for studies on the prognostic accuracy of anterograde aortic isthmus flow compared with retrograde aortic isthmus flow in singleton pregnancy with FGR. The meta-analysis was registered on PROSPERO and was assessed according to PRISMA and Newcastle-Ottawa Scale. DerSimonian and Laird's random-effect model was used for relative risks, Freeman-Tukey Double Arcsine for pooled estimates and exact method to stabilize variances and CIs. Heterogeneity was quantified using I2 statistics. RESULTS: A total of 2933 articles were identified through the electronic search, of which 6 studies (involving 240 women) were included. The quality evaluation of studies revealed an overall acceptable score for study group selection and comparability and substantial heterogeneity. The risk of perinatal death was significantly greater in fetuses with retrograde Aortic Isthmus blood flow, with a RR of 5.17 (p value 0.00001). Similarly, the stillbirth rate was found to have a RR of 5.39 (p value 0.00001). Respiratory distress syndrome had a RR of 2.64 (p value = 0.03) in the group of fetuses with retrograde Aortic Isthmus blood flow. CONCLUSION: Aortic Isthmus Doppler study may add information for FGR management. However, additional clinical trial are required to assess its applicability in clinical practice.


Assuntos
Aorta Torácica , Retardo do Crescimento Fetal , Resultado da Gravidez , Ultrassonografia Pré-Natal , Feminino , Humanos , Gravidez , Aorta Torácica/diagnóstico por imagem , Retardo do Crescimento Fetal/diagnóstico por imagem , Feto/irrigação sanguínea , Natimorto , Ultrassonografia Doppler/métodos , Ultrassonografia Pré-Natal/métodos , Morte Fetal
9.
Ultrasound Obstet Gynecol ; 63(2): 251-257, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37610831

RESUMO

OBJECTIVES: To evaluate the relationship between the attitude of the fetal head quantified by means of the chin-to-chest angle (CCA) in fetuses in occiput posterior (OP) position at the beginning of the second stage of labor, and persistent OP position at birth. METHODS: This was a single-center, prospective observational study conducted at the University Hospital of Parma, Parma, Italy. We included singleton pregnancies at term with fetuses in the OP position at the beginning of the second stage of labor. The fetal head position, station by means of angle of progression and head-to-perineum distance, and attitude by means of CCA were assessed using transabdominal or transperineal ultrasound. The primary outcome was persistent OP position at birth. RESULTS: Between January and July 2022, 76 women were included in the study. There were 48 (63.2%) spontaneous rotations of the fetal head and spontaneous vaginal delivery occurred in all. Among the 28 (36.8%) fetuses that did not rotate spontaneously into an occiput anterior position, eight (28.6%) had a spontaneous vaginal delivery, while operative vaginal delivery and Cesarean delivery was performed in 11 (39.3%) and nine (32.1%) cases, respectively. Multivariable logistic regression analysis showed that the CCA (adjusted odds ratio (aOR), 2.15 (95% CI, 1.22-3.78); P = 0.008) and nulliparity (aOR, 0.20 (95% CI, 0.06-0.76); P = 0.02) were associated independently with persistent OP position at birth. Moreover, the CCA showed an area under the receiver-operating-characteristics curve of 0.69 (95% CI, 0.56-0.82); P = 0.005) for the prediction of persistent OP position. The optimal cut-off value of the CCA was 36.5°, and was associated with a sensitivity of 0.82 (95% CI, 0.63-0.94), specificity of 0.50 (95% CI, 0.35-0.65), positive predictive value of 0.49 (95% CI, 0.34-0.64), negative predictive value of 0.83 (95% CI, 0.64-0.94), positive likelihood ratio of 1.64 (95% CI, 1.18-2.29) and negative likelihood ratio of 0.36 (95% CI, 0.15-0.83). CONCLUSIONS: Our data show that, within a population of women with fetal OP position at the beginning of the second stage of labor, the sonographic fetal head attitude measured by means of the CCA might help in the identification of fetuses at risk of persistent OP position. Such findings can be useful for patient counseling when OP position is diagnosed at full cervical dilatation. Further studies should investigate if the CCA might select patients who may benefit from manual rotation of the fetal head. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Feto , Apresentação no Trabalho de Parto , Recém-Nascido , Gravidez , Feminino , Humanos , Estudos Prospectivos , Feto/diagnóstico por imagem , Segunda Fase do Trabalho de Parto , Ultrassonografia Pré-Natal , Parto Obstétrico , Cabeça/diagnóstico por imagem
10.
Ultrasound Obstet Gynecol ; 63(1): 53-59, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37970655

RESUMO

OBJECTIVES: To determine if the lower-extremity neurological motor function level in fetuses with open spina bifida deteriorates within the 4-week interval between a first prenatal motor assessment at around 22 weeks of gestation and a second evaluation, prior to 'late' prenatal surgery, defined as surgery at 26-28 weeks and, in certain situations, up to 30 weeks, and to assess the association between prenatal presurgical motor-function level, anatomical level of the lesion and postnatal motor-function level. METHODS: This was a two-center cohort study of 94 singleton fetuses with open spina bifida which underwent percutaneous repair using the skin-over-biocellulose for antenatal fetoscopic repair (SAFER) technique between December 2016 and January 2022. All women underwent two prenatal systematic ultrasound evaluations, approximately 4 weeks apart, with the second one being performed less than 1 week before surgery, and one postnatal evaluation via physical examination within 2 months of birth. Motor-function classification was from spinal level T12 to S1, according to key muscle function. Each leg was analyzed separately; in case of discrepancy between the two legs, the worst motor-function level was considered for analysis. Motor-function-level evaluations were compared with each other and with the anatomical level as observed on ultrasound. Independent predictors of a postnatal reduction in motor-function level were assessed using a logistic regression model. RESULTS: Prenatal motor-function level was assessed at a median gestational age of 22.5 (interquartile range (IQR), 20.7-24.3) and 26.7 (IQR, 25.4-27.3) weeks, with a median interval of 4.0 (IQR, 2.4-6.0) weeks. The median gestational age at surgery was 27.0 (IQR, 25.9-27.6) weeks and the postnatal examination was at median age of 0.8 (IQR, 0.3-5.4) months. There was no significant difference in motor-function level between the two prenatal evaluations (P = 0.861). We therefore decided to use the second prenatal evaluation for comparison with postnatal motor function and anatomical level. Overall, prenatal and postnatal motor function evaluations were significantly different from the anatomical level (preoperative assessment, P = 0.0015; postnatal assessment, P = 0.0333). Comparing prenatal with postnatal motor-function level, we found that 87.2% of babies had similar or improved motor function compared with that prior to prenatal surgery. On logistic regression analysis, lower anatomical level of defect and greater difference between anatomical level and prenatal motor-function level were identified as independent predictors of postnatal motor function (odds ratio, 0.237 (95% CI, 0.095-0.588) (P = 0.002) and 3.44 (95% CI, 1.738-6.813) (P < 0.001), respectively). CONCLUSIONS: During a 4-week interval between first ultrasound evaluation and late fetal surgical repair of open spina bifida, motor function does not change significantly, suggesting that late repair, ≥ 26 weeks, does not impact negatively on motor-function outcome. Compared with the anatomical level of the lesion, preoperative neurological motor-function assessment via ultrasound is more predictive of postnatal motor function, and should be included in preoperative counseling. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Espinha Bífida Cística , Disrafismo Espinal , Lactente , Feminino , Gravidez , Humanos , Recém-Nascido , Espinha Bífida Cística/diagnóstico por imagem , Espinha Bífida Cística/cirurgia , Idade Gestacional , Estudos de Coortes , Disrafismo Espinal/diagnóstico por imagem , Disrafismo Espinal/cirurgia , Feto , Estudos Retrospectivos
11.
J Ultrasound Med ; 43(3): 455-465, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37994216

RESUMO

OBJECTIVES: This retrospective study aimed to assess disparities between prenatal ultrasound and autopsy findings in pregnancies that resulted in fetal loss, and to evaluate the diagnostic performance of prenatal ultrasound using postmortem examinations as a gold standard. METHODS: Our study included 136 autopsy cases following a fetal loss that occurred at our tertiary medical center for 8 years. A comparison between the prenatal ultrasound and autopsy findings was made, and all cases were classified according to the degree of agreement. The diagnostic performance of prenatal ultrasound was calculated at the level of organ system and specific malformations. RESULTS: The primary sonographic diagnosis was confirmed in 91.9% of the cases (n = 125). General agreement was highest among central nervous system (CNS), cardiovascular and musculoskeletal systems (85.7%, n = 36, 18, and 12, respectively) and lowest among facial, multiple anomalies, genitourinary and gastrointestinal systems (50.0%, 74.3%, 78.6%, and 80.0%, n = 2, 26, 11, and 4, respectively). The sensitivity of ultrasound was highest in the CNS (93.2%) and musculoskeletal (87.0%) and lowest in the facial (32.3%) and pulmonary (13.0%) systems. Specifically, low diagnostic rates were noted in detecting ventriculomegaly, valvular anomalies, renal dysplasia, spleen and adrenal anomalies, and digital and facial defects. CONCLUSIONS: Our study observed an overall high agreement between prenatal ultrasound and autopsy while contributing to our comprehensive understanding of its strengths and limitations across various types of organ systems and specific malformations.


Assuntos
Malformações do Sistema Nervoso , Ultrassonografia Pré-Natal , Gravidez , Feminino , Humanos , Ultrassonografia Pré-Natal/métodos , Estudos Retrospectivos , Feto , Autopsia , Diagnóstico Pré-Natal/métodos
12.
Prenat Diagn ; 44(1): 49-56, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38126921

RESUMO

OBJECTIVES: To evaluate changes occurring in the fetal brain prior to very preterm delivery using MRI T2* relaxometry, an indirect assessment of tissue perfusion. METHOD: Fetuses that subsequently delivered spontaneously <32 weeks gestation and a control cohort were identified from pre-existing datasets. Participants had undergone a 3T MRI assessment including T2* relaxometry of the fetal brain using a 2D multi-slice gradient echo single shot echo planar imaging sequence. T2* maps were generated, supratentorial brain tissue was manually segmented and mean T2* values were generated. Groups were compared using quadratic regression. RESULTS: Twenty five fetuses that subsequently delivered <32 weeks and 67 that delivered at term were included. Mean gestation at MRI was 24.5 weeks (SD 3.3) and 25.4 weeks (SD 3.1) and gestation at delivery 25.5 weeks (SD 3.4) and 39.7 weeks (SD 1.2) in the preterm and term cohorts respectively. Brain mean T2* values were significantly lower in fetuses that subsequently delivered before 32 weeks gestation (p < 0.001). CONCLUSION: Alterations in brain maturation appear to occur prior to preterm delivery. Further work is required to explore these associations, but these findings suggest a potential window for therapeutic neuroprotective agents in fetuses at high risk of preterm delivery in the future.


Assuntos
Nascimento Prematuro , Recém-Nascido , Feminino , Humanos , Nascimento Prematuro/diagnóstico por imagem , Projetos Piloto , Lactente Extremamente Prematuro , Imageamento por Ressonância Magnética/métodos , Feto , Encéfalo
13.
Eur J Obstet Gynecol Reprod Biol ; 293: 106-114, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38141484

RESUMO

OBJECTIVES: To compare mean pulmonary T2* values and pulmonary volumes in fetuses that subsequently spontaneously delivered before 32 weeks with a control cohort with comparable gestational ages and to assess the value of mean pulmonary T2* as a predictor of preterm birth < 32 weeks' gestation. METHODS: MRI datasets scanned at similar gestational ages were selected from fetuses who spontaneously delivered < 32 weeks of gestation and a control group who subsequently delivered at term with no complications. All women underwent a fetal MRI on a 3 T MRI imaging system. Sequences included T2-weighted single shot fast spin echo and T2* sequences, using gradient echo single shot echo planar sequencing of the fetal thorax. Motion correction was performed using slice-to-volume reconstruction and T2* maps generated using in-house pipelines. Lungs were manually segmented and volumes and mean T2* values calculated for both lungs combined and left and right lung separately. Linear regression was used to compare values between the preterm and control cohorts accounting for the effects of gestation. Receiver operating curves were generated for mean T2* values and pulmonary volume as predictors of preterm birth < 32 weeks' gestation. RESULTS: Datasets from twenty-eight preterm and 74 control fetuses were suitable for analysis. MRI images were taken at similar fetal gestational ages (preterm cohort (mean ± SD) 24.9 ± 3.3 and control cohort (mean ± SD) 26.5 ± 3.0). Mean gestational age at delivery was 26.4 ± 3.3 for the preterm group and 39.9 ± 1.3 for the control group. Mean pulmonary T2* values remained constant with increasing gestational age while pulmonary volumes increased. Both T2* and pulmonary volumes were lower in the preterm group than in the control group for all parameters (both combined, left, and right lung (p < 0.001 in all cases). Adjusted for gestational age, pulmonary volumes and mean T2* values were good predictors of premature delivery in fetuses < 32 weeks (area under the curve of 0.828 and 0.754 respectively). CONCLUSION: These findings indicate that mean pulmonary T2* values and volumes were lower in fetuses that subsequently delivered very preterm. This may suggest potentially altered oxygenation and indicate that pulmonary morbidity associated with prematurity has an antenatal antecedent. Future work should explore these results correlating antenatal findings with long term pulmonary outcomes.


Assuntos
Lactente Extremamente Prematuro , Nascimento Prematuro , Humanos , Recém-Nascido , Gravidez , Feminino , Projetos Piloto , Nascimento Prematuro/diagnóstico por imagem , Feto , Pulmão/diagnóstico por imagem , Idade Gestacional , Imageamento por Ressonância Magnética/métodos
14.
J Exp Zool A Ecol Integr Physiol ; 341(3): 242-255, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38155514

RESUMO

The present study aimed to unravel the possible adverse effects of methomyl on the developing adrenal gland of rat fetuses and pups. Additionally, this study explored the potential improving effects of propolis against these possible hazards induced by methomyl exposure. To achieve that, pregnant rats were divided into four groups: control group, received 1 mL distilled water, propolis group, received 1 mL propolis at a dose of 300 mg/kg, methomyl group, received 1 mL methomyl at a dose of 2 mg/kg, and combined group, received 1 mL methomyl followed by 1 mL propolis, an hour later at the same previous doses. The results revealed that methomyl exposure, during pregnancy and lactation, induced many histological and ultrastructural changes, caused DNA damage and downregulated the expression of steroidogenic acute regulatory (StAR) and CYP11B2 genes in the adrenal glands of both rat fetuses and pups. Interestingly, propolis supplementation demonstrated a remarkable ability to mitigate these deleterious effects and restored the histology and ultrastructure architecture of the adrenal glands of both fetuses and pups, as well as decreased DNA damage and upregulated the expression of StAR and CYP11B2 genes in the adrenal gland of rat fetuses and pups. In conclusion, our study highlights the potential hazardous impact of methomyl exposure during pregnancy and lactation on the development of the adrenal gland in rat fetuses and pups, moreover, the study presents a new approach to alleviate these effects through propolis administration which could be used as a dietary supplement to mitigate the adverse effects of methomyl exposure.


Assuntos
Metomil , Própole , Gravidez , Feminino , Ratos , Animais , Metomil/metabolismo , Metomil/farmacologia , Própole/farmacologia , Própole/metabolismo , Citocromo P-450 CYP11B2/metabolismo , Citocromo P-450 CYP11B2/farmacologia , Glândulas Suprarrenais , Feto , Suplementos Nutricionais
16.
Med Image Anal ; 90: 102977, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37778101

RESUMO

In obstetric sonography, the quality of acquisition of ultrasound scan video is crucial for accurate (manual or automated) biometric measurement and fetal health assessment. However, the nature of fetal ultrasound involves free-hand probe manipulation and this can make it challenging to capture high-quality videos for fetal biometry, especially for the less-experienced sonographer. Manually checking the quality of acquired videos would be time-consuming, subjective and requires a comprehensive understanding of fetal anatomy. Thus, it would be advantageous to develop an automatic quality assessment method to support video standardization and improve diagnostic accuracy of video-based analysis. In this paper, we propose a general and purely data-driven video-based quality assessment framework which directly learns a distinguishable feature representation from high-quality ultrasound videos alone, without anatomical annotations. Our solution effectively utilizes both spatial and temporal information of ultrasound videos. The spatio-temporal representation is learned by a bi-directional reconstruction between the video space and the feature space, enhanced by a key-query memory module proposed in the feature space. To further improve performance, two additional modalities are introduced in training which are the sonographer gaze and optical flow derived from the video. Two different clinical quality assessment tasks in fetal ultrasound are considered in our experiments, i.e., measurement of the fetal head circumference and cerebellar diameter; in both of these, low-quality videos are detected by the large reconstruction error in the feature space. Extensive experimental evaluation demonstrates the merits of our approach.


Assuntos
Feto , Ultrassonografia Pré-Natal , Gravidez , Feminino , Humanos , Ultrassonografia Pré-Natal/métodos , Feto/diagnóstico por imagem , Ultrassonografia
17.
J Physiol ; 601(23): 5413-5436, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37906114

RESUMO

Late gestational supine positioning reduces maternal cardiac output due to inferior vena caval (IVC) compression, despite increased collateral venous return. However, little is known about the impact of maternal position on oxygen (O2 ) delivery and consumption of the gravid uterus, fetus, placenta and lower limbs. We studied the effects of maternal positioning on these parameters in 20 healthy pregnant subjects at 36 ± 2 weeks using magnetic resonance imaging (MRI); a follow-up MRI was performed 6-months postpartum (n = 16/20). MRI techniques included phase-contrast and T1/T2 relaxometry for blood flow and oximetry imaging, respectively. O2 transport was measured in the following vessels (bilateral where appropriate): maternal abdominal descending aorta (DAoabdo ), IVC, ovarian, paraspinal veins (PSV), uterine artery (UtA) and external iliacs, and umbilical. Maternal cardiac output was measured by summing DAothoracic and superior vena cava flows. Supine mothers (n = 6) had lower cardiac output and O2 delivery in the DAoabdo , UtA and external iliac arteries, and higher PSV flow than those in either the left (n = 8) or right (n = 6) lateral positions during MRI. However, O2 consumption in the gravid uterus, fetus, placenta and lower limbs was unaffected by maternal positioning. The ratio of IVC/PSV flow decreased in supine mothers while ovarian venous flow and O2 saturation were unaltered, suggesting a major route of pelvic venous return unaffected by maternal position. Placental-fetal O2 transport and consumption were similar between left and right lateral maternal positions. In comparison to non-pregnant findings, DAoabdo and UtA O2 delivery and pelvic O2 consumption increased, while lower-limb consumption remained constant , despite reduced external iliac artery O2 delivery in late gestation. KEY POINTS: Though sleeping supine during the third trimester is associated with an increased risk of antepartum stillbirth, the underlying biological mechanisms are not fully understood. Maternal cardiac output and uteroplacental flow are reduced in supine mothers due to inferior vena caval compression from the weight of the gravid uterus. This MRI study provides a comprehensive circulatory assessment, demonstrating reduced maternal cardiac output and O2 delivery (uteroplacental, lower body) in supine compared to lateral positioning; however, O2 consumption (gravid uterus, fetus, placenta, lower limbs) was preserved. Unlike other mammalian species, the ovarian veins conduct substantial venous return from the human pregnant uterus that is unaffected by maternal positioning. Lumbar paraspinal venous flow increased in supine mothers. These observations may have important considerations during major pelvic surgery in pregnancy (i.e. placenta percreta). Future studies should address the importance of maternal positioning as a potential tool to deliver improved perinatal outcomes in pregnancies with compromised uteroplacental O2 delivery.


Assuntos
Placenta , Veia Cava Superior , Feminino , Humanos , Gravidez , Estudos de Viabilidade , Feto/diagnóstico por imagem , Feto/irrigação sanguínea , Imageamento por Ressonância Magnética , Oxigênio , Consumo de Oxigênio , Placenta/diagnóstico por imagem
18.
Prenat Diagn ; 43(12): 1506-1513, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37853803

RESUMO

OBJECTIVE: Our objective was to determine the optimal timing of delivery of growth restricted fetuses with gastroschisis in the setting of normal umbilical artery (UA) Dopplers. METHODS: We designed a decision analytic model using TreeAge software for a hypothetical cohort of 2000 fetuses with isolated gastroschisis, fetal growth restriction (FGR), and normal UA Dopplers across 34-39 weeks of gestation. This model accounted for costs and quality adjusted life years (QALYs) for the pregnant individual and the neonate. Model outcomes included stillbirth, respiratory distress syndrome (RDS), necrotizing enterocolitis (NEC), intraventricular hemorrhage (IVH), short gut syndrome (SGS), neonatal sepsis, neonatal death, and neurodevelopmental disability (NDD). RESULTS: We found 38 weeks to be the optimal timing of delivery for minimizing overall perinatal mortality and leading to the highest total QALYs. Compared to 37 weeks, delivery at 38 weeks resulted in 367.98 more QALYs, 2.22 more cases of stillbirth, 2.41 fewer cases of RDS, 0.02 fewer cases of NEC, 1.65 fewer cases of IVH, 0.5 fewer cases of SGS, 2.04 fewer cases of sepsis, 11.8 fewer neonatal deaths and 3.37 fewer cases of NDD. However, 39 weeks were the most cost-effective strategy with a savings of $1,053,471 compared to 38 weeks. Monte Carlo analysis demonstrated that 38 weeks was the optimal gestational age for delivery 51.70% of the time, 39 weeks were optimal 47.40% of the time, and 37 weeks was optimal 0.90% of the time. CONCLUSION: Taking into consideration a range of adverse perinatal outcomes and cost effectiveness, 38-39 weeks gestation is ideal for the delivery of fetuses with gastroschisis, FGR, and normal UA Dopplers. However, there are unique details to consider for each case, and the timing of delivery should be individualized using shared multidisciplinary decision making.


Assuntos
Gastrosquise , Morte Perinatal , Síndrome do Desconforto Respiratório do Recém-Nascido , Gravidez , Feminino , Recém-Nascido , Humanos , Lactente , Natimorto , Feto , Ultrassonografia Doppler/métodos , Idade Gestacional , Retardo do Crescimento Fetal , Técnicas de Apoio para a Decisão
20.
Placenta ; 142: 119-127, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37699274

RESUMO

INTRODUCTION: This study was designed to test the efficacy of an ultrasound flow measurement method to evaluate placental function in a hyperandrogenic sheep model that produces placental morphologic changes and an intrauterine growth restriction (IUGR) phenotype. MATERIALS AND METHODS: Pregnant ewes were assigned randomly between control (n = 12) and testosterone-treatment (T-treated, n = 22) groups. The T-treated group was injected twice weekly intramuscularly (IM) with 100 mg testosterone propionate. Control sheep were injected with corn oil vehicle. Lambs were delivered at 119.5 ± 0.48 days gestation. At the time of delivery of each lamb, flow spectra were generated from one fetal artery and two fetal veins, and the spectral envelopes examined using fast Fourier transform analysis. Base 10 logarithms of the ratio of the amplitudes of the maternal and fetal spectral peaks (LRSP) in the venous power spectrum were compared in the T-treated and control populations. In addition, we calculated the resistive index (RI) for the artery defined as ((peak systole - min diastole)/peak systole). Two-tailed T-tests were used for comparisons. RESULTS: LRSPs, after removal of significant outliers, were -0.158 ± 0.238 for T-treated and 0.057 ± 0.213 for control (p = 0.015) animals. RIs for the T-treated sheep fetuses were 0.506 ± 0.137 and 0.497 ± 0.086 for controls (p = 0.792) DISCUSSION: LRSP analysis distinguishes between T-treated and control sheep, whereas RIs do not. LRSP has the potential to identify compromised pregnancies.


Assuntos
Feto , Placenta , Ovinos , Gravidez , Animais , Feminino , Humanos , Placenta/irrigação sanguínea , Feto/irrigação sanguínea , Veias Umbilicais , Artérias , Artérias Umbilicais , Retardo do Crescimento Fetal/veterinária
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