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1.
PLoS One ; 19(6): e0296985, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38889117

RESUMO

Deep neural networks have been widely adopted in numerous domains due to their high performance and accessibility to developers and application-specific end-users. Fundamental to image-based applications is the development of Convolutional Neural Networks (CNNs), which possess the ability to automatically extract features from data. However, comprehending these complex models and their learned representations, which typically comprise millions of parameters and numerous layers, remains a challenge for both developers and end-users. This challenge arises due to the absence of interpretable and transparent tools to make sense of black-box models. There exists a growing body of Explainable Artificial Intelligence (XAI) literature, including a collection of methods denoted Class Activation Maps (CAMs), that seek to demystify what representations the model learns from the data, how it informs a given prediction, and why it, at times, performs poorly in certain tasks. We propose a novel XAI visualization method denoted CAManim that seeks to simultaneously broaden and focus end-user understanding of CNN predictions by animating the CAM-based network activation maps through all layers, effectively depicting from end-to-end how a model progressively arrives at the final layer activation. Herein, we demonstrate that CAManim works with any CAM-based method and various CNN architectures. Beyond qualitative model assessments, we additionally propose a novel quantitative assessment that expands upon the Remove and Debias (ROAD) metric, pairing the qualitative end-to-end network visual explanations assessment with our novel quantitative "yellow brick ROAD" assessment (ybROAD). This builds upon prior research to address the increasing demand for interpretable, robust, and transparent model assessment methodology, ultimately improving an end-user's trust in a given model's predictions. Examples and source code can be found at: https://omni-ml.github.io/pytorch-grad-cam-anim/.


Assuntos
Redes Neurais de Computação , Inteligência Artificial , Humanos , Algoritmos , Aprendizado Profundo
2.
Sci Rep ; 14(1): 9013, 2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641713

RESUMO

Deep learning algorithms have demonstrated remarkable potential in clinical diagnostics, particularly in the field of medical imaging. In this study, we investigated the application of deep learning models in early detection of fetal kidney anomalies. To provide an enhanced interpretation of those models' predictions, we proposed an adapted two-class representation and developed a multi-class model interpretation approach for problems with more than two labels and variable hierarchical grouping of labels. Additionally, we employed the explainable AI (XAI) visualization tools Grad-CAM and HiResCAM, to gain insights into model predictions and identify reasons for misclassifications. The study dataset consisted of 969 ultrasound images from unique patients; 646 control images and 323 cases of kidney anomalies, including 259 cases of unilateral urinary tract dilation and 64 cases of unilateral multicystic dysplastic kidney. The best performing model achieved a cross-validated area under the ROC curve of 91.28% ± 0.52%, with an overall accuracy of 84.03% ± 0.76%, sensitivity of 77.39% ± 1.99%, and specificity of 87.35% ± 1.28%. Our findings emphasize the potential of deep learning models in predicting kidney anomalies from limited prenatal ultrasound imagery. The proposed adaptations in model representation and interpretation represent a novel solution to multi-class prediction problems.


Assuntos
Aprendizado Profundo , Nefropatias , Sistema Urinário , Gravidez , Feminino , Humanos , Ultrassonografia Pré-Natal/métodos , Diagnóstico Pré-Natal/métodos , Nefropatias/diagnóstico por imagem , Sistema Urinário/anormalidades
3.
J Obstet Gynaecol Can ; 46(6): 102455, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38583665

RESUMO

OBJECTIVES: Investigations about cesarean delivery (CD) on maternal request (CDMR) and infant infection risk frequently rely on administrative data with poorly defined indications for CD. We sought to determine the association between CDMR and infant infection using an intent-to-treat approach. METHODS: This was a population-based cohort study of low-risk singleton pregnancies with a term live birth in Ontario, Canada between April 2012 and March 2018. Subjects with prior CD were excluded. Outcomes included upper and lower respiratory tract infections, gastrointestinal infections, otitis media, and a composite of these 4. Relative risk and 95% CI were calculated for component and composite outcomes up to 1 year following planned CDMR versus planned vaginal deliveries (VDs). Subgroup and sensitivity analyses included age at infection (≤28 vs. >28 days), type of care (ambulatory vs. hospitalisation), restricting the cohort to nulliparous pregnancies, and including individuals with previous CD. Last, we re-examined outcome risk on an as-treated basis (actual CD vs. actual VD). RESULTS: Of 422 134 pregnancies, 0.4% (1827) resulted in a planned CDMR. After adjusting for covariates, planned CDMR was not associated with a risk of composite infant infections (adjusted relative risk 1.02; 95% CI 0.92-1.11). Findings for component infection outcomes, subgroup, and sensitivity analyses were similar. However, the as-treated analysis of the role of delivery mode on infant risk for infection demonstrated that actual CD (planned and unplanned) was associated with an increased risk for infant infections compared to actual VD. CONCLUSIONS: Planned CDMR is not associated with increased risk for neonatal or infant infections compared with planned VD. Study design must be carefully considered when investigating the impact of CDMR on infant infection outcomes.


Assuntos
Cesárea , Humanos , Feminino , Cesárea/estatística & dados numéricos , Gravidez , Ontário/epidemiologia , Adulto , Recém-Nascido , Estudos de Coortes , Infecções Respiratórias/epidemiologia , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Otite Média/epidemiologia
4.
BMC Nurs ; 22(1): 384, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845635

RESUMO

BACKGROUND: Due to heightened occupational stress throughout the COVID-19 pandemic, hospital nurses have experienced high rates of depression, anxiety, and burnout. Nurses in obstetrical departments faced unique challenges, such as the management of COVID-19 infection in pregnancy with limited evidence-based protocols and the unknown risks of the virus on pregnancy and fetal development. Despite evidence that obstetrical nurses have experienced high levels of job stress and a decrease in job satisfaction during the COVID-19 pandemic, there is less known about the working conditions resulting in these changes. Using the Job Demands-Resources (JD-R) model, this study aims to offer insight into the COVID-19 working environment of obstetrical nurses and shed light on their COVID-19 working experiences. METHODS: The study was conducted using a qualitative approach, with data collection occurring through semi-structured interviews from December 2021 to June 2022. A total of 20 obstetrical nurses recruited from the obstetrical departments of a tertiary hospital located in Ontario, Canada, participated in the study. Interviews were audio-recorded, transcribed verbatim, and coded using NVivo. Data was analyzed using a theoretical thematic approach based on the JD-R model. RESULTS: Four themes were identified: (1) Job stressors, (2) Consequences of working during COVID-19, (3) Personal resources, and (4) Constructive feedback surrounding job resources. The findings show that obstetrical nurses faced several unique job stressors during the COVID-19 pandemic but were often left feeling inadequately supported and undervalued by hospital upper management. However, participants offered several suggestions on how they believe support could have been improved and shared insight on resources they personally used to cope with job stress during the pandemic. A model was created to demonstrate the clear linkage between the four main themes. CONCLUSIONS: This qualitative study can help inform hospital management and public policy on how to better support and meet the needs of nurses working in obstetrical care during pandemics. Moreover, applying the JD-R model offers both a novel and comprehensive look at how the COVID-19 hospital work environment has influenced obstetrical nurses' well-being and performance.

5.
Int J Obes (Lond) ; 47(12): 1269-1277, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37833559

RESUMO

OBJECTIVE: The impact of gestational weight loss (GWL) on fetal growth among women with obesity remains unclear. This study aimed to examine the association between weight loss during pregnancy among women with body mass index (BMI) ≥ 30 kg/m2 and the risk of small-for-gestational-age (SGA) and large-for-gestational-age (LGA) neonates. METHODS: We conducted a retrospective, population-based cohort study of women with pre-pregnancy obesity that resulted in a singleton live birth in 2012-2017, using birth registry data in Ontario, Canada. Women with pregnancy complications or health conditions which could cause weight loss were excluded. GWL is defined as negative gestational weight change (≤0 kg). The association between GWL and fetal growth was estimated using generalized estimating equation models and restricted cubic spline regression analysis. Stratified analysis was conducted by obesity class (I:30-34.9 kg/m2, II:35-39.9 kg/m2, and III + : ≥40 kg/m2). RESULTS: Of the 52,153 eligible women who entered pregnancy with a BMI ≥ 30 kg/m2, 5.3% had GWL. Compared to adequate gestational weight gain, GWL was associated with an increased risk of SGA neonates (aRR:1.45, 95% CI: 1.30-1.60) and a decreased risk of LGA neonates (aRR: 0.81, 95% CI:0.73-0.93). Non-linear L-shaped associations were observed between gestational weight change and SGA neonates, with an increased risk of SGA observed with increased GWL. On the contrary, non-linear S-shaped associations were observed between gestational weight change and LGA neonates, with a decreased risk of LGA observed with increased GWL. Similar findings were observed from the stratified analysis by obesity class. CONCLUSION: These findings highlight that GWL in women with obesity may increase the risk of SGA neonates but reduce the risk of LGA neonates. Recommendations of GWL for women with obesity should be interpreted with caution.


Assuntos
Obesidade , Aumento de Peso , Gravidez , Recém-Nascido , Feminino , Humanos , Estudos Retrospectivos , Estudos de Coortes , Obesidade/complicações , Obesidade/epidemiologia , Recém-Nascido Pequeno para a Idade Gestacional , Desenvolvimento Fetal , Redução de Peso , Retardo do Crescimento Fetal , Ontário/epidemiologia , Índice de Massa Corporal , Peso ao Nascer , Resultado da Gravidez/epidemiologia
6.
J Matern Fetal Neonatal Med ; 36(1): 2200879, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37073421

RESUMO

BACKGROUND: Low-dose aspirin is recommended for pregnant individuals at high-risk of developing preeclampsia, but less is known about those that develop preeclampsia even while using prophylactic aspirin for preeclampsia prevention as the best course of treatment. OBJECTIVES: The objective of this study is to investigate the risk factors with the highest risk of developing preeclampsia among pregnant individuals already using aspirin from high-risk obstetrical centers across five countries. DESIGN: This is a secondary analysis of pregnant individuals from the Folic Acid Clinical Trial (FACT) who were using prophylactic aspirin before 16 weeks gestation. The FACT randomized control trial took place in 70 high risk obstetrical centers in Canada, United Kingdom, Australia, Jamaica, and Argentina between 2011-2015. Participants were included if they had any of the risk factors for preeclampsia: diabetes, chronic hypertension, twin pregnancy, history of preeclampsia, and/or obesity (Body Mass Index ≥35). The outcomes of interest were preeclampsia and preterm preeclampsia (<37 weeks). Log binomial regressions assessed factors significantly associated with any preeclampsia or preterm-preeclampsia (<37 weeks) using adjusted risk ratios (ARR) and 95% confidence intervals (CI). RESULTS: There were 2296 pregnant individuals with complete information on aspirin included in this study. At baseline, all patients were at high risk of preeclampsia and were eligible for aspirin prophylaxis, however, only 660 (28.7%) were taking aspirin. Among the 660 pregnant individuals taking aspirin, 132 (20%) developed preeclampsia and 60 (9.09%) preterm preeclampsia. Among pregnant individuals using aspirin, the risks of preeclampsia were highest for twins (ARR:2.62, 95% CI: 1.68-4.11), history of preeclampsia (ARR: 2.42, 95% CI: 1.74-3.38), and hypertension (ARR:1.92, 95% CI: 1.37-2.69). Similar trends were found for preterm-preeclampsia for twins (ARR:4.10, 95% CI:2.15-7.82), history of preeclampsia (ARR:2.75, 95% CI:1.62-4.67), and hypertension (ARR:2.18, 95% CI:1.28-3.72). No significant differences were found for obesity or diabetes. CONCLUSION: These findings suggest that individuals with twin pregnancies, a history of preeclampsia, or hypertension may not benefit from aspirin to the same extent as those with other complications such as obesity or diabetes. Careful clinical monitoring for these risks factors is recommended and future research into the effectiveness in these populations would increase our understanding of the current best practice of prophylactic aspirin use to prevent preeclampsia. TRIAL REGISTRATION: Current Controlled Trials ISRCTN23781770 and ClinicalTrials.gov NCT01355159.


Assuntos
Hipertensão , Pré-Eclâmpsia , Feminino , Humanos , Recém-Nascido , Gravidez , Aspirina/uso terapêutico , Ácido Fólico , Hipertensão/complicações , Obesidade/complicações , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/prevenção & controle , Pré-Eclâmpsia/tratamento farmacológico , Gravidez de Alto Risco , Estudos Retrospectivos , Fatores de Risco
7.
BMC Public Health ; 22(1): 2418, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36550543

RESUMO

BACKGROUND: COVID-19 vaccines are recommended for pregnant and lactating individuals, and there is substantial evidence for their safety and effectiveness. As the pandemic continues, information on worries and beliefs surrounding perinatal COVID-19 vaccination remains important to inform efforts aimed at improving vaccine uptake. Our objectives were to assess factors associated with COVID-19 vaccination among perinatal individuals; and to explore motivational factors associated with willingness to be vaccinated among unvaccinated perinatal individuals. METHODS: This was a cross-sectional web-based survey of preconception, pregnant, and lactating individuals in Canada. The outcomes of interest were vaccination with at least one dose of any COVID-19 vaccine and willingness to be vaccinated among unvaccinated individuals. Sample characteristics were summarized using frequencies and percentages. The association between eight prespecified risk factors and two outcomes (vaccination status and willingness to be vaccinated) was assessed by logistic regression. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for the total sample, and across perinatal sub-groups. RESULTS: Among 3446 survey respondents, there were 447 (13.0%) preconception, 1832 (53.2%) pregnant, and 1167 (42.4%) lactating. There were 1460 (42.4%) and 1982 (57.5%) who were vaccinated and unvaccinated, respectively. Factors positively associated with COVID-19 vaccine status were speaking to a healthcare provider about vaccination during the perinatal period (aOR:2.35, 95% CI:1.97-2.80) and believing that the COVID-19 vaccine is effective (aOR:1.91, 95% CI:1.46-2.48). Factors negatively associated with vaccine status included worries about fetal growth and development (aOR:0.55, 95% CI:0.43-0.70) and future child behavioral/neurodevelopmental problems (aOR:0.59, 95% CI:0.46-0.75). Among unvaccinated individuals specifically, characteristics positively associated with willingness to vaccinate were speaking to a healthcare provider (aOR:1.67, 95% CI:1.32-2.12) and believing the COVID-19 vaccine is effective (aOR:3.56, 95% CI:2.70-4.69). Factors negatively associated with willingness were concerns over infertility (aOR:0.66, 95% CI:0.49-0.88), fetal growth and development (aOR:0.33, 95% CI:0.24-0.46), and future child behavioral/neurodevelopmental problems (aOR:0.64, 95% CI:0.48-0.84). CONCLUSIONS: In this Canadian perinatal population, approximately 42% reported COVID-19 vaccination. Among unvaccinated individuals, willingness to receive vaccination was high (73%). Factors enhancing vaccine willingness included discussions with healthcare providers and believing the vaccine was effective. Concerns regarding vaccine safety, particularly with respect to fetal/child development, were the greatest barriers to vaccine uptake.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Criança , Feminino , Gravidez , Humanos , Estudos Transversais , Lactação , COVID-19/epidemiologia , COVID-19/prevenção & controle , Canadá/epidemiologia , Vacinação
8.
BMJ Open ; 12(12): e066196, 2022 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-36549747

RESUMO

INTRODUCTION: Cannabis use in pregnancy and post partum is increasing. Accessibility to cannabis has expanded due to the legalisation of cannabis in Canada. Therefore, there is a critical need to monitor the impact of cannabis on pregnancy outcomes and infant neurodevelopment. This pilot study will assess the feasibility of modern recruitment and data collection strategies adapted to the current cannabis environment and inform the design of a multicentre prospective birth cohort. METHODS AND ANALYSIS: We will establish a pregnancy and birth cohort of 50 cannabis users and 50 non-users recruited before delivery. We will follow the participants at regular visits from recruitment to 12 weeks post partum. Participants will provide demographic and socioeconomic data, report their cannabis use patterns, and provide biological samples. Biological samples include maternal and infant urine and blood, breastmilk/chestmilk, cord blood, cord tissue, placenta and meconium. All samples will be processed and stored at -80°C until analysis by immunoassay or liquid chromatography-tandem mass spectrometry to determine the presence of cannabis metabolites. In addition, partners will be invited to provide additional socioeconomic and substance use data. ETHICS AND DISSEMINATION: Ethics was obtained from Ottawa Health Science Network Research Ethics Board through Clinical Trials Ontario (3791). Our findings will be published in peer-reviewed journals, presented at scientific conferences and shared broadly with patients, healthcare decision-makers, and project partners online and through social media. TRIAL REGISTRATION NUMBER: NCT05309226.Cite Now.


Assuntos
Cannabis , Gravidez , Lactente , Feminino , Humanos , Projetos Piloto , Estudos Prospectivos , Coorte de Nascimento , Saúde do Lactente , Projetos de Pesquisa , Ontário
9.
J Clin Med ; 11(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35887949

RESUMO

Women who develop preeclampsia (PE) are at high risk for cardiovascular disease (CVD). Early identification of women with PE who may benefit the most from early cardiovascular risk screening and interventions remains challenging. Our objective was to assess whether cytokine and immune cell profiles after PE are helpful in distinguishing women at low and high CVD risk at 6-months postpartum. Individuals who developed PE were followed for immune cell phenotyping and plasma cytokine quantification at delivery, at 3-months, and at 6-months postpartum. Lifetime CVD risk was assessed at 6-months postpartum, and the immune cell and cytokine profiles were compared between risk groups at each time point. Among 31 participants, 18 (58.1%) exhibited high CVD-risk profiles at 6-months postpartum. The proportion of circulating NK-cells was significantly lower in high-risk participants at delivery (p = 0.04). At 3-months postpartum, high-risk participants exhibited a lower proportion of FoxP3+ regulatory T-cells (p = 0.01), a greater proportion of CD8+ T cells (p = 0.02) and a lower CD4+:CD8+ ratio (p = 0.02). There were no differences in immune cell populations at 6-months postpartum. There were no differences in plasma cytokines levels between risk groups at any time point. Subtle differences in immune cell profiles may help distinguish individuals at low and high CVD risk in the early postpartum period and warrants further investigation.

10.
Matern Child Health J ; 26(9): 1753-1761, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35895161

RESUMO

OBJECTIVE: Obstetrical patients are at risk of complications from COVID-19 and face increased stress due to the pandemic and changes in hospital birth setting. The objective was to describe the perinatal care experiences of obstetrical patients who gave birth during the early phases of the COVID-19 pandemic. METHODS: A descriptive epidemiological survey was administered to consenting patients who gave birth at The Ottawa Hospital (TOH) between March 16th and June 16th, 2020. The participants reported on prenatal, in-hospital, and postpartum care experiences. COVID-19 pandemic related household stress factors were investigated. Frequencies and percentages are presented for categorical variables and median and interquartile range (IQR) for continuous variables. RESULTS: A total of 216 participants were included in the analyses. Median participants age was 33 years (IQR: 30-36). Collectively, 94 (43.5%) participants felt elevated stress for prenatal appointments and 105 (48.6%) for postpartum appointments because of COVID-19. There were 108 (50.0%) were scared to go to the hospital for delivery, 97 (44.9%) wore a mask during labour and 54 (25.0%) gave birth without a support person. During postpartum care, 125 (57.9%) had phone appointments (not offered prior to COVID-19), and 18 (8.3%) received no postpartum care at all. CONCLUSION: COVID-19 pandemic and public health protocols created a stressful healthcare environment for the obstetrical population where many were fearful of accessing services, experienced changes to standard care, or no care at all. As the pandemic continues, careful attention should be given to the perinatal population to reduce stress and improve continuity of care.


RéSUMé: OBJECTIF: Les patients obstétriques sont à risque de complications de la COVID-19 et font face à un stress accru en raison de la pandémie et des changements dans le cadre de l'accouchement en milieu hospitalier. L'objectif était de décrire les expériences de soins périnataux des patients obstétriques qui ont accouché au cours des premières phases de la pandémie de COVID-19. MéTHODES: Un sondage épidémiologique descriptif a été menée auprès de patients qui ont accouché à L'Hôpital d'Ottawa (TOH) entre le 16 mars et le 16 juin 2020. Les participants ont fait un compte rendu de leurs expériences en matière de soins prénataux, hospitaliers et post-partum. Les facteurs de stress domestique liés à la COVID-19 ont été étudiés. Les fréquences et les pourcentages sont présentés pour les variables catégorielles et la médiane et l'écart interquartile (IQR) sont présentés pour les variables continues. RéSULTATS: Au total, 261 participants ont répondu au sondage. L'âge maternel médian était de 33 ans (IQR: 30­36). Collectivement, 94 participants (43,5%) ressentaient un stress élevé en lien avec les rendez-vous prénataux et 105 (48,6%) pour les rendez-vous post-partum en raison de la COVID-19. Il y avait 108 patients (50,0%) qui avaient peur d'aller à l'hôpital pour accoucher, 97 (44,9%) qui portaient un masque pendant leur travail et 54 (25,0%) qui ont accouché sans personne de soutien. En lien avec les soins post-partum, 125 (57,9%) ont eu des rendez-vous téléphoniques (non offerts avant la pandémie COVID-19) et 18 (8,3%) n'ont reçu aucun soin post-partum. CONCLUSION: La pandémie de COVID-19 et les politiques de santé publique ont créé un environnement de soins de santé stressant pour la population obstétrique où beaucoup avaient peur d'accéder aux services de soins, ont connu des changements dans les soins de base ou n'ont pas eu de soins du tout. Alors que la pandémie se poursuit, une attention particulière doit être accordée à la population périnatale afin de réduire le stress et améliorer la continuité des soins.


Assuntos
COVID-19 , Adulto , COVID-19/epidemiologia , Feminino , Humanos , Pandemias , Parto , Avaliação de Resultados da Assistência ao Paciente , Período Pós-Parto , Gravidez
11.
CMAJ Open ; 10(3): E643-E651, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35820683

RESUMO

BACKGROUND: There is limited information on the prevalence of SARS-CoV-2 infection in obstetric settings in Canada, beyond the first wave of the COVID-19 pandemic (February to June 2020). We sought to describe the prevalence of SARS-CoV-2 infection in pregnant people admitted to triage units at a tertiary care hospital in Ottawa, Canada. METHODS: We conducted a descriptive study of pregnant people admitted to obstetric triage assessment units at The Ottawa Hospital between Oct. 19 and Nov. 27, 2020 (second local wave of the COVID-19 pandemic). Participants underwent SARS-CoV-2 polymerase chain reaction (PCR) (via naso- or oropharyngeal swabs) and serology testing upon admission. We excluded individuals younger than 18 years, those who did not speak English or French, those who enrolled in conflicting studies, those admitted for pregnancy termination and those triaged between 11:31 pm and 7:29 am. Swab and serology samples were analyzed using digital droplet PCR and enzyme-linked immunosorbent assays, respectively. We defined SARS-CoV-2 seropositivity as a positive result for immunoglobulin (Ig) G, either alone or in combination with IgM or IgA. RESULTS: Of the 632 eligible patients, 363 (57.4%) consented to participation and 362 collectively provided 284 swab and 352 blood samples eligible for analysis. Common reasons for declining participation included feeling overwhelmed or anxious, being worried about repercussions of testing, pain or discomfort with testing or disinterest in research. Participants were mostly multiparous (53.9%) and in their third trimester upon admission (88.4%). In all, 18 (4.9%) participants had evidence of SARS-CoV-2 exposure; 2 (0.7%) of 284 were positive for SARS-CoV-2 by PCR and 16 (4.5%) of 352 were positive for IgG antibodies to SARS-CoV-2. INTERPRETATION: During the second local wave of the COVID-19 pandemic, the prevalence of active SARS-CoV-2 infection among obstetric patients in Ottawa was 0.7% and seroprevalence was 4.5%. Our low participation rate highlights the need for improvements in patient education and public health messaging on the benefits of SARS-CoV-2 testing programs.


Assuntos
COVID-19 , Anticorpos Antivirais , COVID-19/diagnóstico , COVID-19/epidemiologia , Teste para COVID-19 , Canadá/epidemiologia , Humanos , Imunoglobulina G , Pandemias , Prevalência , SARS-CoV-2/genética , Estudos Soroepidemiológicos
12.
PLoS One ; 17(6): e0269323, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35731736

RESUMO

OBJECTIVE: To develop and internally validate a deep-learning algorithm from fetal ultrasound images for the diagnosis of cystic hygromas in the first trimester. METHODS: All first trimester ultrasound scans with a diagnosis of a cystic hygroma between 11 and 14 weeks gestation at our tertiary care centre in Ontario, Canada were studied. Ultrasound scans with normal nuchal translucency were used as controls. The dataset was partitioned with 75% of images used for model training and 25% used for model validation. Images were analyzed using a DenseNet model and the accuracy of the trained model to correctly identify cases of cystic hygroma was assessed by calculating sensitivity, specificity, and the area under the receiver-operating characteristic (ROC) curve. Gradient class activation heat maps (Grad-CAM) were generated to assess model interpretability. RESULTS: The dataset included 289 sagittal fetal ultrasound images;129 cystic hygroma cases and 160 normal NT controls. Overall model accuracy was 93% (95% CI: 88-98%), sensitivity 92% (95% CI: 79-100%), specificity 94% (95% CI: 91-96%), and the area under the ROC curve 0.94 (95% CI: 0.89-1.0). Grad-CAM heat maps demonstrated that the model predictions were driven primarily by the fetal posterior cervical area. CONCLUSIONS: Our findings demonstrate that deep-learning algorithms can achieve high accuracy in diagnostic interpretation of cystic hygroma in the first trimester, validated against expert clinical assessment.


Assuntos
Aprendizado Profundo , Linfangioma Cístico , Aberrações Cromossômicas , Feminino , Humanos , Linfangioma Cístico/diagnóstico por imagem , Ontário , Gravidez , Primeiro Trimestre da Gravidez , Ultrassonografia Pré-Natal
13.
J Perinat Med ; 50(8): 1096-1099, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-35589556

RESUMO

OBJECTIVES: The establishment of cut-offs for normal amniotic fluid volume (AFV) is valuable to predict perinatal outcomes. However, the most common methods to measure AFV are not accurate enough. It is important to understand factors that may be able to increase the accuracy of the calculation of AFV cut-off values. The objective of this study was to verify the correlation between AFV and estimated fetal weight (EFW). METHODS: Records from almost 7,000 patients between 2012 and 2017 were accessed through hospital databases. The AFV measurements included in our analysis were obtained using the maximum vertical pocket technique. RESULTS: AFV was positively correlated with EFW in the overall, male and female samples; however, the magnitude of the association was small (0.1

Assuntos
Líquido Amniótico , Peso Fetal , Líquido Amniótico/diagnóstico por imagem , Feminino , Idade Gestacional , Humanos , Masculino , Gravidez , Gestantes , Cuidado Pré-Natal , Ultrassonografia Pré-Natal
14.
Artigo em Inglês | MEDLINE | ID: mdl-35206265

RESUMO

Obesity is a well-recognized risk factor for pregnancy complications. Most studies to date are in large cohorts, with results presented in a way that assumes all women living with obesity are at equal risk. This study investigates which women living with obesity are at higher risk of specific pregnancy complications. A systematic search of MEDLINE and Embase identified 7894 prospective or retrospective cohort studies exploring predictors of adverse outcomes among pregnant women living with obesity. Following screening, 61 studies were deemed eligible. Studies were selected if the effects of exposure to any predictor amongst pregnant women living with obesity could be collected. Maternal characteristics assessed for association with adverse outcomes included maternal age, race/ethnicity, maternal height, mode of conception, complement activation factors, and history of various comorbidities/procedures. Gestational diabetes mellitus was the most studied outcome (n = 32), followed by preterm birth (n = 29), preeclampsia (n = 27), low birthweight infants (n = 20), small for gestational age newborns (n = 12), and stillbirth (n = 7). This review identified important characteristics that should be considered during the screening and follow-up sessions of pregnant women living with obesity, including pre-existing type 1 diabetes, maternal age < 20 years or ≥35 years, non-White ethnicity, abdominal adiposity obesity, and history of bariatric surgery.


Assuntos
Complicações na Gravidez , Nascimento Prematuro , Adulto , Feminino , Humanos , Lactente , Recém-Nascido , Obesidade/epidemiologia , Gravidez , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Gestantes , Estudos Prospectivos , Estudos Retrospectivos , Adulto Jovem
15.
BMJ Open ; 11(5): e049295, 2021 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-34045216

RESUMO

OBJECTIVE: The objectives of this study were to: (1) document violent and controlling behaviours within intimate partnerships during the perinatal period; and (2) determine individual, interpersonal and household-level factors influencing the risk of perinatal intimate partner violence (IPV). DESIGN: Cross-sectional survey. SETTING: The Ottawa Hospital, Department of Obstetrics and Gynecology, Ottawa, Ontario, Canada. PARTICIPANTS: Patients who gave birth at The Ottawa Hospital and were >20 days post partum between 17 March and 16 June 2020. MAIN OUTCOMES AND MEASURES: Perinatal IPV was defined as regular controlling behaviours or act-based forms of emotional/physical/sexual abuse in the 12 months before pregnancy, during pregnancy and/or post partum. Log-binomial multivariable regression models were used to compute adjusted risk ratios (aRRs) and 95% CIs to identify potential risk factors for IPV: maternal age, postpartum depression, parity, increase in partner substance use and household income. RESULTS: Among 216 participants, the median maternal age was 33 years (IQR: 30-36). In total, 52 (24.07%) reported some form of perinatal IPV, 37 (17.13%) reported regular controlling behaviour and 9 (4.17%) reported both. Household income below the municipal median was the strongest risk factor for perinatal IPV (aRR: 3.24, 95% CI: 1.87 to 5.59). There was no apparent association between maternal age (aRR: 0.99, 95% CI: 0.94 to 1.04), postpartum depression (aRR: 1.03, 95% CI: 1.00 to 1.07), nulliparity (aRR: 1.18, 95% CI: 0.71 to 1.97) or increases in partner substance use (aRR: 0.73, 95% CI: 0.42 to 1.25) with IPV. CONCLUSION: One in four individuals in this study experienced perinatal IPV. Household income was the strongest risk factor, and surprisingly, many hypothesised risk factors (eg, mental health, partner substance use, etc) were not significantly associated with perinatal IPV in this sample. This highlights the challenges in both measuring IPV and identifying individuals exposed to perinatal IPV during the high stress of the COVID-19 pandemic.


Assuntos
COVID-19 , Violência por Parceiro Íntimo , Adulto , Estudos Transversais , Feminino , Humanos , Ontário/epidemiologia , Pandemias , Período Pós-Parto , Gravidez , Prevalência , Fatores de Risco , SARS-CoV-2
16.
CMAJ ; 193(18): E634-E644, 2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33941522

RESUMO

BACKGROUND: Data on the effect of cesarean delivery on maternal request (CDMR) on maternal and neonatal outcomes are inconsistent and often limited by inadequate case definitions and other methodological issues. Our objective was to evaluate the trends, determinants and outcomes of CDMR using an intent-to-treat approach. METHODS: We designed a population-based retrospective cohort study using data on low-risk pregnancies in Ontario, Canada (April 2012-March 2018). We assessed temporal trends and determinants of CDMR. We estimated the relative risks for component and composite outcomes used in the Adverse Outcome Index (AOI) related to planned CDMR compared with planned vaginal delivery using generalized estimating equation models. We compared the Weighted Adverse Outcome Score (WAOS) and the Severity Index (SI) across planned modes of delivery using analysis of variance. RESULTS: Of 422 210 women, 0.4% (n = 1827) had a planned CDMR and 99.6% (n = 420 383) had a planned vaginal delivery. The prevalence of CDMR remained stable over time at 3.9% of all cesarean deliveries. Factors associated with CDMR included late maternal age, higher education, conception via in vitro fertilization, anxiety, nulliparity, being White, delivery at a hospital providing higher levels of maternal care and obstetrician-based antenatal care. Women who planned CDMR had a lower risk of adverse outcomes than women who planned vaginal delivery (adjusted relative risk 0.42, 95% confidence interval [CI] 0.33 to 0.53). The WAOS was lower for planned CDMR than planned vaginal delivery (mean difference -1.28, 95% CI -2.02 to -0.55). The SI was not statistically different between groups (mean difference 3.6, 95% CI -7.4 to 14.5). INTERPRETATION: Rates of CDMR have not increased in Ontario. Planned CDMR is associated with a decreased risk of short-term adverse outcomes compared with planned vaginal delivery. Investigation into the long-term implications of CDMR is warranted.


Assuntos
Cesárea/estatística & dados numéricos , Parto Obstétrico/métodos , Procedimentos Cirúrgicos Eletivos/psicologia , Preferência do Paciente , Adulto , Canadá/epidemiologia , Cesárea/efeitos adversos , Estudos de Coortes , Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Feminino , Humanos , Recém-Nascido , Idade Materna , Paridade , Vigilância da População , Gravidez , Resultado da Gravidez/epidemiologia , Estudos Retrospectivos
17.
J Nutr ; 151(7): 1976-1982, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33851221

RESUMO

BACKGROUND: Periconceptional folic acid (FA) supplementation is recommended to prevent neural tube defects; however, the extent to which recommendations are met through dietary sources and supplements is not clear. OBJECTIVES: Our objective was to evaluate the dietary and supplemental intakes of FA in a Canadian pregnancy cohort and to determine the proportions of pregnant women exceeding the Estimated Average Requirement (EAR) and Tolerable Upper Intake Level (UL). METHODS: FACT (the Folic Acid Clinical Trial) was an international multicenter, randomized, double-blinded, placebo-controlled, phase III trial investigating FA for the prevention of pre-eclampsia in high-risk pregnancies. Participants were enrolled from Canadian sites at 8-16 weeks of gestation. Dietary and supplemental FA intake data were collected through participant interviews and FFQs at the time of FACT enrollment. Categorical data were summarized as n (%) and continuous data as median (IQR). RESULTS: This study included 1198 participants. Participants consumed 485 µg dietary folate equivalents (DFE)/d (IQR: 370-630 µg DFE/d) from dietary sources of folate and FA. Through diet alone, 43.4% of participants consumed ≥520 µg DFE/d, the EAR for pregnant individuals. Of the 91.9% of participants who consumed daily FA supplements, 0.4% consumed <400 µg FA/d and 96.0% consumed ≥1000 µg/d, the UL for FA. Median (IQR) total folate intake was 2167 µg DFE/d (2032-2325 µg DFE/d); 95.3% of participants met or exceeded the EAR from all sources, but 1069 (89.2%) participants exceeded the UL. CONCLUSIONS: The majority of participants in this Canadian pregnancy cohort did not consume the recommended amount of folate from dietary sources. However, most prenatal supplements contained 1000 µg FA, resulting in the majority of women exceeding the UL. With no additional benefit associated with FA intakes beyond the UL for most women, modification of prenatal supplement formulations may be warranted to ensure women meet but do not exceed recommended FA intakes.FACT was registered at clinicaltrials.gov as NCT01355159 and at isrctn.com as ISRCTN23781770.


Assuntos
Ácido Fólico , Pré-Eclâmpsia , Canadá , Suplementos Nutricionais , Feminino , Humanos , Pré-Eclâmpsia/prevenção & controle , Gravidez , Vitaminas
18.
Am J Clin Nutr ; 113(5): 1361-1371, 2021 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-33675351

RESUMO

BACKGROUND: Periconceptional folic acid (FA) supplementation is recommended to prevent the occurrence of neural tube defects. Currently, most over-the-counter FA supplements in Canada and the United States contain 1 mg FA and some women are prescribed 5 mg FA/d. High-dose FA is hypothesized to impair 1-carbon metabolism. We aimed to determine folate and 1-carbon metabolism biomarkers in pregnant women exposed to 1 mg or 5 mg FA. OBJECTIVES: This was an ancillary study within the Folic Acid Clinical Trial (FACT), a randomized, double-blinded, placebo-controlled, phase III trial designed to assess the efficacy of high-dose FA to prevent preeclampsia. METHODS: For FACT, women were randomized at 8-16 gestational weeks to receive daily 4.0 mg FA (high dose) or placebo (low dose) plus their usual supplementation (≤1.1 mg). Women were recruited from 3 Canadian FACT centers and provided nonfasting blood samples at 24-26 gestational weeks for measurement of RBC and serum total folate, serum unmetabolized FA (UMFA), tetrahydrofolate (THF), 5-methylTHF, 5-formylTHF, 5,10-methenylTHF, and MeFox (pyrazino-s-triazine derivative of 4α-hydroxy-5-methylTHF, a 5-methylTHF oxidation product); total vitamins B-12 and B-6; and plasma total homocysteine. Group differences were determined using χ2, Fisher exact, and Wilcoxon rank-sum tests. RESULTS: Nineteen (38%) women received high-dose FA and 31 (62%) received low-dose FA. The median RBC folate concentration was 2701 (IQR: 2243-3032) nmol/L and did not differ between groups. The high-dose group had higher serum total folate (median: 148.4 nmol/L, IQR: 110.4-181.2; P = 0.007), UMFA (median: 4.6 nmol/L, IQR: 2.5-33.8; P = 0.008), and 5-methylTHF (median: 126.6 nmol/L, IQR: 98.8-158.6; P = 0.03) compared with the low-dose group (median: 122.8 nmol/L, IQR: 99.5-136.0; median: 1.9 nmol/L, IQR: 0.9-4.1; median: 108.6 nmol/L, IQR: 96.4-123.2, respectively). Other biomarkers of 1-carbon metabolism did not differ. CONCLUSIONS: High-dose FA supplementation in early pregnancy increases maternal serum folate but not RBC folate concentrations, suggesting tissue saturation. Higher UMFA concentrations in women receiving high-dose FA supplements suggest that these doses are supraphysiologic but with no evidence of altered 1-carbon metabolism.


Assuntos
Suplementos Nutricionais , Ácido Fólico/administração & dosagem , Ácido Fólico/farmacologia , Complexo Vitamínico B/administração & dosagem , Complexo Vitamínico B/farmacologia , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/metabolismo , Biomarcadores/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Metilenotetra-Hidrofolato Desidrogenase (NADP)/metabolismo , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Polimorfismo de Nucleotídeo Único , Gravidez
19.
BMC Pregnancy Childbirth ; 21(1): 182, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33673827

RESUMO

BACKGROUND: Approximately one in five pregnant women have obesity. Obesity is associated with an increased risk of antenatal, intrapartum, and perinatal complications, but many women with obesity have uncomplicated pregnancies. At a time where maternity services are advocating for women to make informed choices, knowledge of the chance of having an uncomplicated (healthy) pregnancy is essential. The objective of this study was to calculate the rate of uncomplicated pregnancy in women with obesity and evaluate factors associated with this outcome. METHODS: This prospective cohort study was conducted using the Ontario birth registry dataset in Canada (703,115 women, April 2012-March 2017). The rate of uncomplicated or complicated composite pregnancy outcomes (hypertensive disorders of pregnancy, gestational diabetes, preterm birth, neonate small- or large- for gestational age at birth, congenital anomaly, fetal death, antepartum bleeding or preterm prelabour membrane rupture) were calculated for women with and without obesity. Associations between uncomplicated pregnancy and maternal characteristics were explored in a population of women with obesity but without other pre-existing co-morbidities (e.g., essential hypertension) or obstetric risks identified in the first trimester (e.g., multiple pregnancy), using log binomial regression analysis. RESULTS: Of the studied Ontario maternity population (body mass index not missing) 17·7% (n = 117,236) were obese. Of these 20·6% had pre-existing co-morbidities or early obstetric complicating factors. Amongst women with obesity but without early complicating factors, 58·2% (n = 54,191) experienced pregnancy without complication; this is in comparison to 72·7% of women of healthy weight and no early complicating factors. Women with obesity and no early pregnancy complicating factors are more likely to have an uncomplicated pregnancy if they are multiparous, younger, more affluent, of White or Black ethnicity, of lower weight, with normal placental-associated plasma protein-A and/or spontaneously conceived pregnancies. CONCLUSIONS: The study demonstrates that over half of women with obesity but no other pre-existing medical or early obstetric complicating factors, proceed through pregnancy without adverse obstetric complication. Care in lower-risk settings can be considered as their outcomes appear similar to those reported for low-risk nulliparous women. Further research and predictive tools are needed to inform stratification of women with obesity.


Assuntos
Serviços de Saúde Materna/estatística & dados numéricos , Obesidade , Assistência Perinatal , Complicações na Gravidez , Medição de Risco , Adulto , Declaração de Nascimento , Índice de Massa Corporal , Comorbidade , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Obesidade/diagnóstico , Obesidade/epidemiologia , Ontário/epidemiologia , Paridade , Assistência Perinatal/métodos , Assistência Perinatal/estatística & dados numéricos , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Primeiro Trimestre da Gravidez , Nascimento Prematuro/epidemiologia , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos
20.
Can J Public Health ; 110(5): 657-667, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31452112

RESUMO

OBJECTIVE: To explore inadequate and excessive gestational weight gain (GWG) among pregnant women of different racial/ethnic backgrounds in Ontario, Canada. METHODS: A population-based retrospective cohort study was conducted among women who had prenatal screening and had a singleton birth in an Ontario hospital between April 2016 and March 2017. We estimated adjusted risk ratios (aRR) of racial/ethnic differences for inadequate or excessive GWG using multinomial logistic regression models. Interaction effects were examined to determine whether racial/ethnic difference in GWG varied by pre-pregnancy body mass index (BMI). RESULTS: Among 74,424 women, the prevalence of inadequate GWG in White, Asian, and Black women was 15.7%, 25.8%, and 25.0%, and excessive GWG was 62.8%, 45.5%, and 54.7%, respectively. There were significant interaction effects between race/ethnicity and pre-pregnancy BMI for inadequate GWG (Wald p < 0.01) and excessive GWG (Wald p < 0.01). Compared with White women, Asian women had higher risk of inadequate GWG and lower risk of excessive GWG in all weight classes, and Black women had higher risk of inadequate GWG and lower risk of excessive GWG if their BMI was normal, overweight, or obese. CONCLUSION: Variations in unhealthy GWG by pre-pregnancy weight classes among Ontario White, Asian and Black women were observed. Individualized counseling regarding appropriate GWG is universally recommended. Additional consideration of racial/ethnic variations by maternal weight classes may help to promote healthy GWG in Canada.


Assuntos
Povo Asiático/estatística & dados numéricos , População Negra/estatística & dados numéricos , Ganho de Peso na Gestação/etnologia , Disparidades nos Níveis de Saúde , População Branca/estatística & dados numéricos , Adulto , Feminino , Humanos , Ontário , Gravidez , Adulto Jovem
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