Definition Of Restriction Research Articles

The Significance of the Myocardial Performance Index and Fetal Doppler Abnormalities in Growth-Restricted Fetuses: A Systematic Review of the Literature

Introduction: This review aims to investigate the clinical implications of using the myocardial performance index (MPI), obtained through tissue Doppler imaging (TDI) and spectral Doppler, in assessing fetal cardiac function in growth-restricted fetuses. It explores the MPI’s potential in predicting adverse perinatal outcomes and its utility when combined with conventional pulsed-wave Doppler assessments for enhanced fetal well-being evaluations. Material and Methods: A systematic search of PubMed and Google Scholar databases spanning from 2004 to 2023 was conducted to identify pertinent articles on the MPI’s clinical application in managing growth-restricted fetuses. Inclusion criteria followed the Fetal Medicine Barcelona definition of fetal growth restriction (FGR) to mitigate study group heterogeneity. The research sources were PubMed and Google Scholar databases, and the review was conducted without any specific clinical or laboratory setting. Only articles meeting the inclusion criteria for FGR, as per the Fetal Medicine Barcelona definition, were considered. Six studies meeting these criteria were included in the review. The review analyzed the correlation between MPI values and conventional Doppler parameters, investigating the progression of myocardial function impairment and its association with the risk of fetal demise. The primary outcome measures included the relationship between MPI values, fetal well-being, and the potential for prenatal cardiac dysfunction in growth-restricted fetuses. Results: The findings indicate that as conventional Doppler parameters deteriorate, MPI values increase, suggesting progressive myocardial dysfunction. The MPI may cross the 95th percentile before abnormal flow in the ductus venosus and aortic isthmus, highlighting the potential for diastolic dysfunction preceding hypoxia in growth-restricted fetuses. Elevated MPI levels were observed in both growth-restricted and small-for-gestational-age (SGA) fetuses, indicating prenatal cardiac impairment. The strong association between an abnormal MPI and perinatal mortality has been shown for early FGR. Conclusions: MPI alterations appear to precede abnormal Doppler parameters in early- and late- onset FGR, potentially indicating diastolic dysfunction preceding hypoxia. Additionally, the MPI correlates with the risk of fetal demise. However, larger studies are needed to establish its sensitivity and specificity. Furthermore, the significance of prenatal cardiac impairment in some SGA fetuses raises questions about its potential impact on perinatal outcomes and cardiovascular programming.

Some issues regarding the principles and criteria of lawful restriction of human freedom

The article is devoted to the study of the content and peculiarities of implementation of the principles and criteria for limiting human freedoms. The author concludes that the principle of freedom should be studied through the following aspects: axiological, theoretical and practical. The first one involves maximum absolutisation of the principle of freedom for its further deployment in social relations. The theoretical dimension involves the study of the specifics of the content, types, features, and nature of freedom as a legal principle, which allows for a better understanding of it and its more harmonious implementation in legal relations. The practical dimension involves studying the problems of implementing the principle of freedom, the degree of its presence in various branches of law, and the specifics of its restrictions. The article notes that the principle of proportionality means that restriction of freedom can only be a means, not an aim, freedom is always the highest value for law and its restrictions as the ultimate goal are inadmissible, but only as a regulatory means to ensure rights and freedoms, national security, healthcare, public order, etc. The principle of public welfare as a criterion for restricting freedom is more complicated, since there are two doctrines: classical liberalism, which puts freedom above all else and limits state intervention, and social liberalism, which insists on the welfare of all and therefore more active state intervention in the economic life of society. The author concludes that restrictions on freedom must be in the general public interest in the economic, social and political spheres. The author notes that limitation of the principle of freedom is a reduction of its scope, but not a restriction of its content. By restricting freedom, its content remains unchanged, otherwise it will lose its legal value. The article provides the author’s definition of restriction of the principle of freedom as a lawful interference by the State with the capabilities of a person, which is expressed in setting limits for a possible model of behaviour in a certain territory, individually or for certain groups of persons. The author emphasises that one of the key problems with the implementation of measures restricting human freedom is excessiveness. An important public interest allows for the restriction of freedom to achieve it, but other interests and values may suffer. The principles of minimum possible restriction and priority social value should apply here.

Placental pathology lesions: International Society for Ultrasound in Obstetrics and Gynecology vs Society for Maternal-Fetal Medicine fetal growth restriction definitions

BackgroundResearch on the definition of fetal growth restriction (FGR) has focused on predicting adverse perinatal outcomes. A significant limitation of this approach is that the individual outcomes of interest could be related to the condition and the treatment. Evaluation of outcomes that reflect the pathophysiology of FGR may overcome this limitation. ObjectiveTo compare the diagnostic performance of the FGR definitions established by the International Society for Ultrasound in Obstetrics and Gynecology (ISUOG) and the Society for Maternal-Fetal Medicine (SMFM) to predict placental histopathological findings associated with placental insufficiency and a composite adverse neonatal outcome (ANeO). Study DesignIn this retrospective cohort study of singleton pregnancies, the ISUOG and the SMFM guidelines were used to identify pregnancies with FGR and a corresponding control group. The primary outcome was the prediction of placental histopathological findings associated with placental insufficiency, defined as lesions associated with maternal vascular malperfusion (MVM). A composite ANeO (ie, umbilical artery pH≤7.1, Apgar score at 5 minutes ≤4, neonatal intensive care unit admission, hypoglycemia, respiratory distress syndrome requiring mechanical ventilation, intrapartum fetal distress requiring expedited delivery, and perinatal death) was investigated as a secondary outcome. Sensitivity, specificity, positive and negative predictive values, and the areas under the receiver-operating-characteristics curves were determined for each FGR definition. Logistic regression models were used to assess the association between each definition and the studied outcomes. A subgroup analysis of the diagnostic performance of both definitions stratifying the population in early and late FGR was also performed. ResultsBoth societies’ definitions showed a similar diagnostic performance as well as a significant association with the primary (ISUOG adjusted odds ratio 3.01 [95% confidence interval 2.42, 3.75]; SMFM adjusted odds ratio 2.85 [95% confidence interval 2.31, 3.51]) and secondary outcomes (ISUOG adjusted odds ratio 1.95 [95% confidence interval 1.56, 2.43]; SMFM adjusted odds ratio 2.12 [95% confidence interval 1.70, 2.65]). Furthermore, both FGR definitions had a limited discriminatory capacity for placental histopathological findings of MVM and the composite ANeO (area under the receiver-operating-characteristics curve ISUOG 0.63 [95% confidence interval 0.61, 0.65], 0.59 [95% confidence interval 0.56, 0.61]; area under the receiver-operating-characteristics SMFM 0.63 [95% confidence interval 0.61, 0.66], 0.60 [95% confidence interval 0.57, 0.62]). ConclusionThe ISUOG and the SMFM FGR definitions have limited discriminatory capacity for placental histopathological findings associated with placental insufficiency and a composite ANeO.El resumen está disponible en Español al final del artículo.

Neonatal outcome-based performance of the recent International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) definition of foetal growth restriction: retrospective study

Neonatal outcome-based performance of the recent International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) definition of foetal growth restriction: retrospective study

Prenatal prediction of adverse outcome using different charts and definitions of fetal growth restriction.

Antenatal growth assessment using ultrasound aims to identify small fetuses that are at higher risk of perinatal morbidity and mortality. This study explored whether the association between suboptimal fetal growth and adverse perinatal outcome varies with different definitions of fetal growth restriction (FGR) and different weight charts/standards. This was a retrospective cohort study of 17 261 singleton non-anomalous pregnancies at ≥ 24 + 0 weeks' gestation that underwent routine ultrasound at a tertiary referral hospital. Estimated fetal weight (EFW) and Doppler indices were converted into percentiles using a reference standard (INTERGROWTH-21st (IG-21)) and various reference charts (Hadlock, Fetal Medicine Foundation (FMF) and Swedish). Test characteristics were assessed using the consensus definition, Society for Maternal-Fetal Medicine (SMFM) definition and Swedish criteria for FGR. Adverse perinatal outcome was defined as perinatal death, admission to the neonatal intensive care unit at term, 5-min Apgar score < 7 and therapeutic cooling for neonatal encephalopathy. The association between FGR according to each definition and adverse perinatal outcome was compared. Multivariate logistic regression analysis was used to test the strength of association between ultrasound parameters and adverse perinatal outcome. Ultrasound parameters were also tested for correlation. IG-21, Hadlock and FMF fetal size references classified as growth-restricted 1.5%, 3.6% and 4.6% of fetuses, respectively, using the consensus definition and 2.9%, 8.8% and 10.6% of fetuses, respectively, using the SMFM definition. The sensitivity of the definition/chart combinations for adverse perinatal outcome varied from 4.4% (consensus definition with IG-21 charts) to 13.2% (SMFM definition with FMF charts). Specificity varied from 89.4% (SMFM definition with FMF charts) to 98.6% (consensus definition with IG-21 charts). The consensus definition and Swedish criteria showed the highest specificity, positive predictive value and positive likelihood ratio in detecting adverse outcome, irrespective of the reference chart/standard used. Conversely, the SMFM definition had the highest sensitivity across all investigated growth charts. Low EFW, abnormal mean uterine artery pulsatility index (UtA-PI) and abnormal cerebroplacental ratio were significantly associated with adverse perinatal outcome and there was a positive correlation between the covariates. Multivariate logistic regression showed that UtA-PI > 95th percentile and EFW < 5th percentile were the only parameters consistently associated with adverse outcome, irrespective of the definitions or fetal growth chart/standard used. The apparent prevalence of FGR varies according to the definition and fetal size reference chart/standard used. Irrespective of the method of classification, the sensitivity for the identification of adverse perinatal outcome remains low. EFW, UtA-PI and fetal Doppler parameters are significant predictors of adverse perinatal outcome. As these indices are correlated with one other, a prediction algorithm is advocated to overcome the limitations of using these parameters in isolation. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Validity of a Delphi consensus definition of growth restriction in the newborn for identifying neonatal morbidity

BackgroundSmall-for-gestational age (SGA) is defined as a birthweight below a birthweight-percentile threshold, usually the 10th percentile, with the 3rd or 5th percentile used to identify severe SGA. SGA is used as a proxy for growth restriction in the newborn, but SGA newborns can be physiologically small and healthy. This definition also excludes growth restricted newborns who have weights above the 10th percentile. To address these limits, a Delphi study developed a new consensus definition of growth restriction in the newborn based on neonatal anthropometric and clinical parameters, but it has not been evaluated. ObjectivesTo assess the prevalence of growth restriction in the newborn according to the Delphi consensus definition and to investigate associated morbidity risks compared to definitions of SGA using birthweight-percentile thresholds. Study designData come from the 2016 and 2021 French National Perinatal Surveys which include all births ≥22 weeks and/or with birthweights ≥500 grams in all maternity units in France over a one-week period. Data are collected from medical records and interviews with mothers after the delivery. The study population included 23,897 liveborn singleton births. The Delphi consensus definition of growth restriction was birthweight <3rd percentile or at least 3 of the following criteria: birthweight, head circumference or length <10th percentile, antenatal diagnosis of growth restriction or maternal hypertension. A composite of neonatal morbidity at birth, defined as five-minute Apgar score <7, cord arterial pH <7.10, resuscitation and/or neonatal admission, was compared using the Delphi definition and usual birthweight-percentile thresholds for defining SGA using the following birthweight percentile groups: <3rd, 3rd-4th and 5th-9th percentiles. Relative risks were adjusted (aRR) for maternal characteristics (age, parity, body mass index, smoking, educational level, pre-existing hypertension and diabetes, and study year) and then for the consensus definition and birthweight percentile groups. Multiple imputation by chained equations was used to impute missing data. Analyses were carried out in the overall sample and among term and preterm newborns separately. Results4.9% (95% confidence intervals (CI): 4.6-5.2) of newborns were identified with growth restriction, of whom 29.7% experienced morbidity, yielding a aRR of 2.5 (95% CI: 2.2-2.7) compared to newborns without growth restriction. Compared to birthweight ≥10th percentile, morbidity risks were higher for low birthweight percentiles (<3rd aRR=3.3 (95%CI: 3.0-3.7), 3rd-4th RR=1.4 (95%CI:1.1-1.7), 5th-9th RR=1.4, (95%CI:1.2-1.6)). In adjusted models including the definition of growth restriction and birthweight percentile groups and excluding birthweights <3rd percentile, which are included in both definitions, morbidity risks remained higher for birthweights at the 3rd-4th percentile (aRR=1.4, 95% CI: 1.1-1.7) and 5th-9th percentile (aRR= 1.4, 95%CI: 1.2-1.6), but not for the Delphi definition of growth restriction (aRR= 0.9, 95%CI: 0.7-1.2). Similar patterns were found for term and preterm newborns. ConclusionThe Delphi consensus definition of growth restriction did not identify more newborns with morbidity than definitions of SGA based on birthweight percentiles. These findings illustrate the importance of evaluating the results of Delphi consensus studies before their adoption in clinical practice.

Artificial Intelligence (AI)-Predicted Medical Diagnosis in Suspected Mature B-Cell Neoplasms Based on Flow Cytometric Raw Data

Introduction: AI is becoming an integral part of diagnostic workup solutions worldwide. Using our vast database of flow cytometry data of hematologic neoplasms, we develop AI-powered workflows to support high-throughput routine diagnostics. As one of our most frequent requests is proof / exclusion of B-cell lymphoma, we initially focus on mature B-cell neoplasms (B-NHL), aiming at reliably classifying lymphoma cases and distinguish such from normal controls. Methods: An AI model was developed to decipher flow cytometry data in order to classify B-NHL. To that end, uniformly processed samples analyzed by human experts during standardized routine diagnostics were employed (Navios / Cytoflex cytometers, Kaluza software, Beckman Coulter). The model used 3,830 cases in order to distinguish the lymphoma categories diagnosed in routine setting. The model was built with XGBoost using raw cytometric data and expert-informed features. Recall (R, corresponds to sensitivity), precision (P, proportion of truly positive cases) and prediction probability (PP, confidence of the model in its prediction) were recorded. The predicted diagnosis was compared with the human expert diagnosis and this information was used for further model improvement. The process comprised various steps adapted to the flow cytometric data structure. These include essential technicalities such as data transformation and scaling, cluster formation, careful definition of light chain restriction and feature engineering. Results: Focusing on B-NHL (all categories) versus no lymphoma, the model initially resulted in an average R of 88% and P of 87%. The model distinguished categories 1) no lymphoma (R 95%, P 95%), 2) CLL (R 62%, P 71%), 3) HZL (R 96%, P 96%), 4) FL (R 88%, P 100%), 5) LPL (R 78%, P 70%), 6) MCL (R 97%, P 76%), 7) MZL (R 71%, P 71%) and 8) SBLPN (R 100%, P 100%). We found that 364 out of 3830 (9.5%) cases in our cohort could not be processed by the AI model due to technical limitations. To make these accessible for preprocessing and analysis, downstream improve R and P values, and make the same strategy usable for further Flow-AI models, several technical foundations were revisited. Flow cytometry data uses vastly different data ranges considering e.g. scatter vs. fluorescence properties. Since the model needs to be able to identify main populations of interest (such as lymphocytes, granulocytes, monocytes) in a dynamic fashion, data display was modified laying foundation for all further analysis. Our data show that transformation of the raw values followed by scaling to 0 to 1 enables superior clustering results. Normalization is achieved by the RobustScaler from the scikit-learn library. Implementing proper data transformation and scaling, all 3830 cases could now be successfully processed. The next step was to revisit cluster formation options as they are prerequisite for lymphoma identification in the downstream classifier. We found best results with HDBSCAN after optimizing the hyperparameters for the minimum cluster size and noise eradication to adapt automatically based on the number of CD45 positive cells or other intermediate gating results. We could reduce the rate of failure of correct classification from 20% to 17% by HDBSCAN clustering. Essential further steps included the dynamic definition of the light chain separation enabling the model to adapt to each case´s specificities in terms of expression strength of kappa and lambda. This was followed by updating the features in order to make all new information useful. These processes allowed for higher P values for CLL (71% to 80%) and LPL (70% to 74%) as well as higher R values for follicular lymphoma FL (88% to 89%) MZL (71% to 76%). Conclusion: AI is applicable to analyze flow cytometric data allowing prediction of B-NHL. By fine-tuning data transformation, scaling and clustering we massively improved the analysis pipeline gaining 12.5% of cases that had not been accessible for analysis, and in context with proper light chain definition and feature adaptation we were able to improve R and P values of several lymphoma categories. The improvements are a result of explainable feature engineering which enables us to track the weight and actual value of a feature down to the events in the dot plots and expands on our explainable AI (XAI) strategy. Our work sets the groundwork to fully embark on AI-based B-cell lymphoma identification.

EP13.15: Assessing current definitions of fetal growth restriction in a low‐resource setting

EP13.15: Assessing current definitions of fetal growth restriction in a low‐resource setting

Proposal to expand the definition of intrauterine growth restriction and introduce two new screening methods

The authors of this publication have developed a new screening method to evaluate the physical development of infants, which identifies growth and developmental restrictions based on their gestational age, gender, weight and length standard positions and nourishment status. This so-called MDN-method (MDN = Maturity, Development, Nourishment) offers several benefits: 1. It enables the expansion of the scope and definition of intrauterine growth restriction (IUGR) and the establishment of five separate condition subtypes. 2. It facilitates the study of the risk of mortality of infants based on their development and nourishment status. 3. The method is suitable for the screening of high-risk IUGR infants and neonates. 4. The MDN method allowed for the development of a new ultrasound screening methodology for high-risk IUGR infants and neonates, based on abdominal circumference (AC) and femur length (FL) standards, which correlate the most with the weight and length of the fetus. The data of 1,244,918 Hungarian live and stillbirths recorded during 2000-2012 were used for these studies. It is believed that these new screening methods may have a significant impact on reducing the frequency of IUGR-related stillbirth and infant mortality cases.

Should abdominal circumference

Should abdominal circumference <3rd percentile be included in the definition of severe fetal growth restriction?

Sensitivity of Broadened Definition of Fetal Growth Restriction in Predicting Adverse Neonatal Outcomes [A342

INTRODUCTION: In 2020 the Society for Maternal-Fetal Medicine suggested broadening the fetal growth restriction (FGR) definition to include fetuses with isolated abdominal circumference (AC) less than 10th percentile. The purpose of this study was to determine if including these fetuses improves prediction of severe neonatal morbidity and mortality. METHODS: This is a retrospective analysis of births over the past 10 years within a hospital system affiliated with the University of Minnesota. A pregnancy was included if prenatal ultrasound data were available after 24 weeks gestation. Excluded were non-singletons and fetuses with diagnosis of structural or genetic abnormalities that could affect biometry measurements. Fetuses were categorized as FGR based on the prior definition (estimated fetal weight [EFW] less than 10th percentile) and on the proposed definition of EFW or AC less than 10th percentile. Institutional review board approval was obtained from the University of Minnesota (ID 00011238). RESULTS: A total of 26,526 births met inclusion criteria. The mean gestational age at birth was 39 weeks (SD 0.2). The rate of severe morbidity (e.g., severe acidosis, hypoxic ischemic encephalopathy, and sepsis) and mortality for those with EFW less than 10th percentile was 9.3% (odds ratio [OR] 3.6, P&lt;.001) and 2.8% (OR 26.1, P&lt;.001), respectively. For those with EFW or AC less than 10th percentile, rates were 6% (OR 2.3, P&lt;.001) and 1.5% (OR 15.0, P&lt;.001), respectively. CONCLUSION: Broadening the definition unsurprisingly increased the frequency of FGR, but frequency of adverse outcomes was lower. Thus, this analysis does not support the addition of isolated AC less than 10th percentile to the FGR definition.

Insufficient fetal growth: fetal growth restriction or small for gestational age fetus? The difference between these conditions, what is known about diagnosis, prevention and treatment: A review

The difference between the fetal growth restriction and the small-for-gestational-age fetus was analyzed in this article. The article describes the most complete definition of the fetal growth restriction according to ultrasound data. Information about possible ethology and pathogenesis of the fetal growth restriction, the modern classification of this condition was also summarized in the article. We provide classifications which were used in Russia and all over the world earlier. The article contains information about possible methods of diagnosing the fetal growth restriction with accents on key indicators of dopplerometry and cardiotocography. According to the latest data, the management of patients changes depending on the gestation period. There are significant differences between early and late fetal growth restriction. Futhermore, we tried to research universal methods of prevention and treatment of the fetal growth restriction. We also included data from Russian Society of obstetricians and gynecologists guidelines. The analyzed information shows that the problem of the fetal growth restriction has many unsolved problems and great potential for the further research.

The Delphi definition for selective fetal growth restriction may not improve detection of pathologic growth discordance in monochorionic twins

A consensus definition of selective fetal growth restriction in monochorionic diamniotic twins was recently proposed following a Delphi procedure involving an international panel of experts. The new definition augments the traditional definition with additional sonographic criteria. We sought to determine whether the augmentations of the "Delphi definition" identified additional morbidity and mortality compared with a traditional definition. Furthermore, we sought to determine the benefit of each definition in identifying pathologic growth restriction relative to uncomplicated monochorionic diamniotic twins. This was a retrospective analysis of unselected monochorionic diamniotic twins that underwent fortnightly ultrasound surveillance at a single center between 2011 and 2020. Patients with concomitant twin-to-twin transfusion syndrome, twin anemia polycythemia sequence, or twin reversed arterial perfusion sequence at the time of diagnosis of selective fetal growth restriction were excluded. The diagnosis of selective fetal growth restriction using the Delphi definition required either an estimated fetal weight of <3rd percentile or presence of 2 of 4 observations in the smaller twin: (1) estimated fetal weight of <10th percentile, (2) estimated fetal weight discordance of >25% compared with the larger twin, (3) abdominal circumference of <10th percentile, (4) umbilical artery pulsatility index of >95th percentile. Diagnosis using the traditional definition required an estimated fetal weight of <10th percentile and an estimated fetal weight discordance of >25%. To determine the efficacy of the augmentations in the Delphi definition, 3 groups were compared: group I, uncomplicated monochorionic diamniotic twins; group II, twins with selective fetal growth restriction using the traditional definition (and therefore the Delphi definition); and group III, twins with selective fetal growth restriction solely using the Delphi definition. Demographic characteristics, subsequent development of twin-to-twin transfusion syndrome or twin anemia polycythemia sequence, pregnancy outcomes, and neonatal outcomes were compared. There were 325 patients with monochorionic diamniotic twins that met inclusion criteria. Of these, 213 (66%; group I) were uncomplicated, 37 (11%; group II) met the traditional definition for selective fetal growth restriction, and 112 (35%) met the Delphi definition for selective fetal growth restriction with 75 (67%) meeting solely the Delphi definition (group III). Demographic characteristics were similar between groups. Patients in group II delivered earlier than uncomplicated twins (32.1 vs 35.7 weeks of gestation; P<.01) and patients in group III (32.1 vs 35.6 weeks of gestation; P<.01). Furthermore, they were more likely to have critical umbilical artery Doppler abnormalities (38% vs 4%; P<.01) and be delivered for deteriorating fetal status (30% vs 5%; P<.01) than those in group III. Overall, survival was lower in group II than groups I and III (89% vs 96% and 100%, respectively; P=.04). Moreover, composite neonatal morbidity and mortality were greater in group II (30%) than either group I (6%; P<.01) or group III (9%; P<.01). The rates of composite neonatal morbidity and mortality were similar between groups I and III (P=.28). The addition of abdominal circumference and umbilical artery pulsatility index thresholds and isolated estimated fetal weight of <3%, as proposed by the Delphi definition, increased the diagnosis of selective fetal growth restriction; however, there was no added benefit in the identification of growth discordant pregnancies at risk of adverse outcomes. Prospective analysis of monochorionic diamniotic twins is required to contextualize these findings.

Early-onset fetal growth restriction defined by only abdominal circumference is associated with perinatal mortality

SMFM recently expanded the definition of fetal growth restriction (FGR) to include abdominal circumference < 10th centile (%) as a diagnostic criterion in addition to the classic criterion of estimated fetal weight (EFW) < 10%. The broader definition is associated with improved detection of small for gestational age (SGA) neonates. Early-onset FGR diagnosed based on EFW alone prior to 32 estimated gestational age (EGA) is associated with increased risk of perinatal death. Among fetuses with normal EFW, we aimed to determine whether early-onset FGR diagnosed based on AC alone is associated with increased risks of adverse neonatal outcomes.

Reconsidering upstream approaches to improving population health

Racial and socioeconomic disparities in health outcomes have been well documented. 1 Blumenshine P Egerter S Barclay CJ Cubbin C Braveman PA Socioeconomic disparities in adverse birth outcomes: a systematic review. Am J Prev Med. 2010; 39: 263-272 Summary Full Text Full Text PDF PubMed Scopus (477) Google Scholar , 2 Matoba N Collins Jr, JW Racial disparity in infant mortality. Semin Perinatol. 2017; 41: 354-359 Crossref PubMed Scopus (43) Google Scholar Although overall global rates of poor birth outcomes have decreased, decades of research and interventions have not eliminated disparities. However, much intervention research has focused on individual-level risk factors and groups at high risk. In The Lancet, Jennifer Jardine and colleagues 3 Jardine J Walker K Gurol-Urganci I et al. Adverse pregnancy outcomes attributable to socioeconomic and ethnic inequalities in England: a national cohort study. Lancet. 2021; (published online Nov 1.)https://doi.org/10.1016/S0140-6736(21)01595-6 Summary Full Text Full Text PDF PubMed Scopus (7) Google Scholar report on population attributable fractions, which indicate the proportion of a particular outcome that would be removed if a risk factor did not exist or was more similar to a reference population. The use of population attributable fractions is an important contribution because it demonstrates the excess risk of poor outcomes that can be attributed to population-level factors. The authors provide a potential roadmap for future interventions, emphasising the role of widespread health promotion in improving population-level health metrics over targeted, individual-level interventions that have less population impact. 4 Rose G Sick individuals and sick populations. Int J Epidemiol. 1985; 14: 32-38 Crossref PubMed Scopus (2188) Google Scholar This study 3 Jardine J Walker K Gurol-Urganci I et al. Adverse pregnancy outcomes attributable to socioeconomic and ethnic inequalities in England: a national cohort study. Lancet. 2021; (published online Nov 1.)https://doi.org/10.1016/S0140-6736(21)01595-6 Summary Full Text Full Text PDF PubMed Scopus (7) Google Scholar included 1·16 million singleton births in England, which represented 94% of England's births obtained from administrative hospital data linked to the National Maternity and Perinatal Audit between 2015 and 2017. The authors report that 24% of stillbirths, 19% of preterm births, and 31% of fetal growth restriction could be attributed to socioeconomic inequality. The women included in the sample were 77·2% White, 11·9% south Asian, 4·9% Black, 1·8% mixed ethnicity, and 4·2% other ethnicity. Perhaps most striking were the authors’ findings on the intersection of race and socioeconomic disadvantage, describing that more than half of stillbirths, a third of preterm births, and nearly two-thirds of fetal growth restriction among south Asian and Black women could be eliminated if their risk factors were equal to the least socioeconomically deprived White women. The authors suggest that this finding supports a combination of population-based and risk-based approaches, but does not consider the inextricable link between ethnic background and socioeconomic deprivation. 5 Kane JB Miles G Yourkavitch J King K Neighborhood context and birth outcomes: going beyond neighborhood disadvantage, incorporating affluence. SSM Popul Health. 2017; 3: 699-712 Crossref PubMed Scopus (17) Google Scholar Additionally, the association between race or socioeconomic inequality and birth outcomes might vary because of factors like social support and experiences of racism and discrimination. In combination with the limitation of using an area-level index of deprivation, the authors acknowledge potential inaccuracies and bias in the population attributable fractions. 6 Mansournia MA Altman DG Population attributable fraction. BMJ. 2018; 360: k757 Crossref PubMed Scopus (114) Google Scholar They rightfully note that more detailed causal mediation analysis is a research priority. Moreover, because the definition of fetal growth restriction varies by the reference used, which itself varies by ethnic mix in the index population, 7 Grantz KL Fetal growth curves: is there a universal reference?. Obstet Gynecol Clin North Am. 2021; 48: 281-296 Summary Full Text Full Text PDF PubMed Scopus (2) Google Scholar interpretations of this outcome are unclear. Indeed, the authors may be capturing small-for-gestational age rather than fetal growth restriction, which may not indicate pathology. Adverse pregnancy outcomes attributable to socioeconomic and ethnic inequalities in England: a national cohort studyOur results indicate that socioeconomic and ethnic inequalities were responsible for a substantial proportion of stillbirths, preterm births, and births with FGR in England. The largest inequalities were seen in Black and South Asian women in the most socioeconomically deprived quintile. Prevention should target the entire population as well as specific minority ethnic groups at high risk of adverse pregnancy outcomes, to address risk factors and wider determinants of health. Full-Text PDF

VP34.01: Customised Doppler standards for the definition of late fetal growth restriction

VP34.01: Customised Doppler standards for the definition of late fetal growth restriction

Effect of Maternal and Fetal Characteristics in Feto-Placental Doppler and Impact of Using Adjusted Standards in the Definition of Fetal Growth Restriction at Term

Introduction: This study aimed to determine the effect and clinical impact of physiological characteristics on the 95th/5th centile of the umbilical artery (UA) Doppler and the cerebroplacental ratio (CPR), at 36+ weeks. Methods: From the multicenter randomized trial “Ratio37,” we selected 4,505 low-risk pregnant women between June 2016 and January 2020. We registered physiological characteristics and the pulsatility indexes (PI) of the UA and middle cerebral artery (36–39 weeks). The 95th/5th centile of the UA PI and CPR was modeled by quantile regression. To evaluate the clinical impact of adjusting Doppler, we retrospectively applied gestational age (GA) and fully adjusted standards to 682 small for gestational age (SGA)-suspected fetuses (37 weeks) from a cohort of consecutive patients obtained between January 2010 and January 2020. Results: Several physiological characteristics significantly influenced the 95th/5th centile of the UA and CPR PI. The fully adjusted 95th centile of the UA was higher, and the 5th centile of the CPR was lower than GA-only-adjusted standards. Of the 682 SGA fetuses, 150 (22%) were classified as late fetal growth restricted only by GA and 112 (16.4%) when we adjusted Doppler. These 38 fetuses had similar perinatal outcome than the SGA group. Discussion: The 95th/5th centile of the UA and CPR PI is significantly influenced by physiological characteristics. Adjusting Doppler standards could differentiate better between FGR and SGA.

Impact of adding abdominal circumference to the definition of fetal growth restriction

Fetal growth restriction has traditionally been defined as fetuses with an estimated fetal weight <10th percentile for gestational age. In 2020, the Society for Maternal-Fetal Medicine recommended that the definition be expanded to include either an estimated fetal weight<10th percentile or a fetal abdominal circumference<10th percentile. We sought to determine the impact of adding the criterion abdominal circumference<10th percentile on the rate of diagnosis of fetal growth restriction vs using the criterion estimated fetal weight<10th percentile alone. In addition, we evaluated the definition proposed by Copel and Bahtiyar, estimated fetal weight<10th percentile or abdominal circumference<5th percentile. This was a retrospective, descriptive study from 3 consultative maternal-fetal medicine practices. Biometry was compiled from ultrasound examinations from January 2019 to July 2020. The inclusion criteria were singleton pregnancy, gestational age of ≥24 weeks, presence of fetal cardiac activity, and presence of 4 standard fetal biometry parameters (biparietal diameter, head circumference, abdominal circumference, and femur length). We tabulated the indications for the examinations and the number of examinations meeting several criteria for the diagnosis of fetal growth restriction: Traditional criterion (estimated fetal weight<10th percentile), Copel-Bahtiyar criteria (estimated fetal weight<10th percentile or abdominal circumference<5th percentile), and Society for Maternal-Fetal Medicine criteria (estimated fetal weight<10th percentile or abdominal circumference<10th percentile). During the study period, 20,633 ultrasound examinations met the inclusion criteria. In 62% of examinations, there was ≥1 factor for fetal growth restriction, and in 51% of examinations, there was ≥1 factor for large for gestational age. The rate of estimated fetal weight<10th percentile was 9.7%. The rate of abdominal circumference<5th percentile was 5.7%, and the rate of abdominal circumference<10th percentile was 9.2%. The rate of fetal growth restriction was 9.7% using the traditional definition (estimated fetal weight<10th percentile only). The rate of fetal growth restriction was 10.2% using the Copel-Bahtiyar definition (estimated fetal weight<10th percentile or abdominal circumference<5th percentile), significantly higher than using the traditional definition (P<.001). The rate of fetal growth restriction was 11.6% using the Society for Maternal-Fetal Medicine definition (estimated fetal weight<10th percentile or abdominal circumference<10th percentile), significantly higher than using either the traditional or Copel-Bahtiyar definition (P<.001 for both). Among examinations with an abdominal circumference<10th percentile, 79% also had an estimated fetal weight<10th percentile and was considered fetal growth restriction even without considering abdominal circumference. Adding the criterion abdominal circumference<5th percentile or abdominal circumference<10th percentile to the definition of fetal growth restriction resulted in a statistically significant increase in the rate of diagnosis of fetal growth restriction. However, the absolute increase in the rate was small and was not expected to place a large burden on practice resources.

65 New SMFM definition of fetal growth restriction: Impact of adding AC < 10th percentile

65 New SMFM definition of fetal growth restriction: Impact of adding AC < 10th percentile

782 Difference in ultrasound unit volume between birthweight and ultrasound derived definitions of fetal growth restriction

Recent guidelines recommend the use Hadlock rather than birth weight derived percentiles for diagnosis of fetal growth restriction (FGR). The objective of this study is to quantify the impact of changing from a birth weight (Williams et al.) to an ultrasound based (Hadlock et al.) percentile classification of FGR on ultrasound unit volume. We conducted a retrospective cohort study of all singleton pregnancies that presented for ultrasound ≥22 weeks’ gestation pre- and post an institutional change of FGR classification system from Williams et al. to Hadlock et al. between 2018-2020. Pregnancies with an estimated fetal weight <10% by either classification system were included in the analysis. The primary outcomes were the frequency of patient encounters, follow up examinations, biophysical profiles (BPP) ≥28 weeks, and umbilical artery (UA) Doppler assessments. Secondary outcomes were gestational age (GA) at delivery and rates of cesarean delivery, 5-minute Apgar <7, and fetal death between study years. 550 women met inclusion criteria over the study period. FGR diagnosis was discordant (FGR by Hadlock, but not Williams) in 77.6% of cases at diagnosis and in 46.9% at the last ultrasound before delivery. The median GA at FGR diagnosis was significantly earlier using Hadlock (31.9 vs 36.0 weeks; p<.001). Significant increases in the median number of encounters, BPP, UA Doppler, and total billed procedure codes were calculated between study years; Table 1. Fetal death was decreased (6.0% vs 2.1%; p=.043), but FGR diagnosis was discordant in only 4/15 cases that resulted in fetal death. No differences in GA at delivery, cesarean delivery and Apgar <7 at 5 minutes were identified between study years. Use of Hadlock results in increased rates of FGR and diagnosis at an earlier gestational age when compared to birth weight derived percentiles. This leads to a significant increase in overall ultrasound unit volume including use of UA Doppler surveillance.