Objective To assess causation and clinical presentation of major birth defects.Design Population based case cohort.Setting Cases of birth defects in children born 2005-09 to resident women, ...ascertained through Utah’s population based surveillance system. All records underwent clinical re-review.Participants 5504 cases among 270 878 births (prevalence 2.03%), excluding mild isolated conditions (such as muscular ventricular septal defects, distal hypospadias).Main outcome measures The primary outcomes were the proportion of birth defects with a known etiology (chromosomal, genetic, human teratogen, twinning) or unknown etiology, by morphology (isolated, multiple, minors only), and by pathogenesis (sequence, developmental field defect, or known pattern of birth defects).Results Definite cause was assigned in 20.2% (n=1114) of cases: chromosomal or genetic conditions accounted for 94.4% (n=1052), teratogens for 4.1% (n=46, mostly poorly controlled pregestational diabetes), and twinning for 1.4% (n=16, conjoined or acardiac). The 79.8% (n=4390) remaining were classified as unknown etiology; of these 88.2% (n=3874) were isolated birth defects. Family history (similarly affected first degree relative) was documented in 4.8% (n=266). In this cohort, 92.1% (5067/5504) were live born infants (isolated and non-isolated birth defects): 75.3% (4147/5504) were classified as having an isolated birth defect (unknown or known etiology).Conclusions These findings underscore the gaps in our knowledge regarding the causes of birth defects. For the causes that are known, such as smoking or diabetes, assigning causation in individual cases remains challenging. Nevertheless, the ongoing impact of these exposures on fetal development highlights the urgency and benefits of population based preventive interventions. For the causes that are still unknown, better strategies are needed. These can include greater integration of the key elements of etiology, morphology, and pathogenesis into epidemiologic studies; greater collaboration between researchers (such as developmental biologists), clinicians (such as medical geneticists), and epidemiologists; and better ways to objectively measure fetal exposures (beyond maternal self reports) and closer (prenatally) to the critical period of organogenesis.
People with skeletal dysplasias have left traces in art and antiquities through ages and cultures worldwide, in Ancient Egypt, Classical Greece, Sub‐Saharan Africa, Asia, and Europe. Such traces ...record the impact of people with skeletal dysplasia on society and culture—in daily life, religion, and mythology. However, identifying (“diagnosing”) skeletal dysplasia in artifacts and interpreting what such depictions meant within the culture in which they were created is extremely challenging and at times impossible. The objectives of this short and necessarily selective survey are to present a few examples of art through different ages and cultures as a springboard for discussion not only on potential medical diagnoses but also on the lives of people with chondrodysplasia and how they were valued in the society in which they lived. The artifacts were selected from Ancient Egypt, Classical Greece, Mesoamerica (Maya), Sub‐Saharan Africa (Kingdom of Benin), Tang China, and 17th Century Europe. In some cases, surviving artifacts with likely depictions of skeletal dysplasia are few and their cultural context incompletely understood. Nevertheless, certain themes and attitudes seem to repeat across different times and regions, though some cultures, such as those in Ancient Egypt, appeared to have had a comparatively positive view of people with restricted growth and chondrodysplasia.
Congenital heart disease (CHD) is common, costly, and critical. Approximately half of all infant deaths due to congenital anomalies are associated with CHD or neural tube defects. As infant mortality ...improves due to better infection control and peripartum care, congenital anomalies are becoming a key driver of pediatric survival and health. Improving CHD prevention and care globally will play a significant role toward key goals such as United Nation's sustainable development goals (SDGs) of good health and well‐being (SDG 3) and reduced inequalities (SDG 10). This review addresses two questions: how can we reinterpret and reframe available data on CHD to spur action in prevention and care? How can we re‐engineer how we currently track CHD in populations to efficiently generate new data to assess successes and detect gaps in prevention and care? Answering these questions requires understanding the causal chain of disease, from cause to CHD occurrence to health outcomes. This perspective provides a logical basis for two innovations. First, develop a data‐driven message that reframes epidemiologic and clinical data in terms of incentives for action, evidence for change, and strategies for population‐wide impact. Second, through partnerships between clinical and public health systems, implement an integrated “triple surveillance,” which, in the same population, concurrently tracks the three elements of the causal chain—causes, disease occurrence, health outcomes. By streamlining activities and minimizing operational waste, such systems can have a vital role in improving prevention and care on a population level, including in many low and middle‐income countries.
Preventing neural tube defects (NTDs) easily qualifies as a high‐value opportunity to improve childhood survival and health: the unmet need is significant (major preventable burden), the intervention ...is transformative (providing sufficient folic acid), and delivery strategies (e.g., fortification) are effective in low‐resource countries. Yet, NTD prevention is lagging. Can public health surveillance help fix this problem? Critics contend that surveillance is largely unnecessary, that limited resources are best spent on interventions, and that surveillance is unrealistic in developing countries. The counterargument is twofold: (1) in the absence of surveillance, interventions will provide fewer benefits and cost more and (2) effective surveillance is likely possible nearly everywhere, with appropriate strategies. As a base strategy, we propose “triple surveillance:” integrating surveillance of cause (folate insufficiency), of disease occurrence (NTD prevalence), and of health outcomes (morbidity, mortality, and disability). For better sustainability and usefulness, it is crucial to refocus and streamline surveillance activities (no recreational data collection), weave surveillance into clinical care (integrate in clinical workflow), and, later, work on including additional risk factors and pediatric outcomes (increase benefits at low marginal cost). By doing so, surveillance becomes not a roadblock but a preferential path to prevention and better care.
Background While associations between secondhand smoke and a few birth defects (namely, oral clefts and neural tube defects) have been noted in the scientific literature, to our knowledge, there is ...no single or comprehensive source of population-based information on its associations with a range of birth defects among nonsmoking mothers. Objective We utilized data from the National Birth Defects Prevention Study, a large population-based multisite case-control study, to examine associations between maternal reports of periconceptional exposure to secondhand smoke in the household or workplace/school and major birth defects. Study Design The multisite National Birth Defects Prevention Study is the largest case-control study of birth defects to date in the United States. We selected cases from birth defect groups having >100 total cases, as well as all nonmalformed controls (10,200), from delivery years 1997 through 2009; 44 birth defects were examined. After excluding cases and controls from multiple births and whose mothers reported active smoking or pregestational diabetes, we analyzed data on periconceptional secondhand smoke exposure–encompassing the period 1 month prior to conception through the first trimester. For the birth defect craniosynostosis, we additionally examined the effect of exposure in the second and third trimesters as well due to the potential sensitivity to teratogens for this defect throughout pregnancy. Covariates included in all final models of birth defects with ≥5 exposed mothers were study site, previous live births, time between estimated date of delivery and interview date, maternal age at estimated date of delivery, race/ethnicity, education, body mass index, nativity, household income divided by number of people supported by this income, periconceptional alcohol consumption, and folic acid supplementation. For each birth defect examined, we used logistic regression analyses to estimate both crude and adjusted odds ratios and 95% confidence intervals for both isolated and total case groups for various sources of exposure (household only; workplace/school only; household and workplace/school; household or workplace/school). Results The prevalence of secondhand smoke exposure only across all sources ranged from 12.9–27.8% for cases and 14.5–15.8% for controls. The adjusted odds ratios for any vs no secondhand smoke exposure in the household or workplace/school and isolated birth defects were significantly elevated for neural tube defects (anencephaly: adjusted odds ratio, 1.66; 95% confidence interval, 1.22–2.25; and spina bifida: adjusted odds ratio, 1.49; 95% confidence interval, 1.20–1.86); orofacial clefts (cleft lip without cleft palate: adjusted odds ratio, 1.41; 95% confidence interval, 1.10–1.81; cleft lip with or without cleft palate: adjusted odds ratio, 1.24; 95% confidence interval, 1.05–1.46; cleft palate alone: adjusted odds ratio, 1.31; 95% confidence interval, 1.06–1.63); bilateral renal agenesis (adjusted odds ratio, 1.99; 95% confidence interval, 1.05–3.75); amniotic band syndrome-limb body wall complex (adjusted odds ratio, 1.66; 95% confidence interval, 1.10–2.51); and atrial septal defects, secundum (adjusted odds ratio, 1.37; 95% confidence interval, 1.09–1.72). There were no significant inverse associations observed. Conclusion Additional studies replicating the findings are needed to better understand the moderate positive associations observed between periconceptional secondhand smoke and several birth defects in this analysis. Increased odds ratios resulting from chance (eg, multiple comparisons) or recall bias cannot be ruled out.
July 20, 2021 marked the 30th anniversary of the publication of the landmark trial by the British Medical Research Council showing unequivocally that maternal intake of folic acid (vitamin B9) ...starting before pregnancy prevents most cases of infant spina bifida and anencephaly—two major neural tube defects that are severe, disabling, and often fatal. Mandatory food fortification with folic acid is a safe, cost-effective, and sustainable intervention to prevent spina bifida and anencephaly. Yet few countries implement fortification with folic acid; only a quarter of all preventable spina bifida and anencephaly cases worldwide are currently avoided by food fortification. We summarise scientific evidence supporting immediate, mandatory fortification with folic acid to prevent the development of spina bifida and anencephaly. We make an urgent call to action for the World Health Assembly to pass a resolution for universal mandatory folic acid fortification. Such a resolution could accelerate the slow pace of spina bifida and anencephaly prevention globally, and will assist countries to reach their 2030 Sustainable Development Goals on child mortality and health equity. The cost of inaction is profound, and disproportionately impacts susceptible populations in low-income and middle-income countries.
ObjectivesTo assess international trends and patterns of prenatal diagnosis of critical congenital heart defects (CCHDs) and their relation to total and live birth CCHD prevalence and ...mortality.SettingFifteen birth defect surveillance programmes that participate in the International Clearinghouse for Birth Defects Surveillance and Research from 12 countries in Europe, North and South America and Asia.ParticipantsLive births, stillbirths and elective terminations of pregnancy for fetal anomaly diagnosed with 1 of 12 selected CCHD, ascertained by the 15 programmes for delivery years 2000 to 2014.Results18 243 CCHD cases were reported among 8 847 081 births. The median total prevalence was 19.1 per 10 000 births but varied threefold between programmes from 10.1 to 31.0 per 10 000. CCHD were prenatally detected for at least 50% of the cases in one-third of the programmes. However, prenatal detection varied from 13% in Slovak Republic to 87% in some areas in France. Prenatal detection was consistently high for hypoplastic left heart syndrome (64% overall) and was lowest for total anomalous pulmonary venous return (28% overall). Surveillance programmes in countries that do not legally permit terminations of pregnancy tended to have higher live birth prevalence of CCHD. Most programmes showed an increasing trend in prenatally diagnosed CCHD cases.Discussion and conclusionsPrenatal detection already accounts for 50% or more of CCHD detected in many programmes and is increasing. Local policies and access likely account for the wide variability of reported occurrence and prenatal diagnosis. Detection rates are high especially for CCHD that are more easily diagnosed on a standard obstetric four-chamber ultrasound or for fetuses that have extracardiac anomalies. These ongoing trends in prenatal diagnosis, potentially in combination with newborn pulse oximetry, are likely to modify the epidemiology and clinical outcomes of CCHD in the near future.
Over the last 15 years, Undiagnosed Diseases Programs have emerged to address the significant number of individuals with suspected but undiagnosed rare genetic diseases, integrating research and ...clinical care to optimize diagnostic outcomes. This narrative review summarizes the published literature surrounding Undiagnosed Diseases Programs worldwide, including thirteen studies that evaluate outcomes and two commentary papers. Commonalities in the diagnostic and research process of Undiagnosed Diseases Programs are explored through an appraisal of available literature. This exploration allowed for an assessment of the strengths and limitations of each of the six common steps, namely enrollment, comprehensive clinical phenotyping, research diagnostics, data sharing and matchmaking, results, and follow-up. Current literature highlights the potential utility of Undiagnosed Diseases Programs in research diagnostics. Since participants have often had extensive previous genetic studies, research pipelines allow for diagnostic approaches beyond exome or whole genome sequencing, through reanalysis using research-grade bioinformatics tools and multi-omics technologies. The overall diagnostic yield is presented by study, since different selection criteria at enrollment and reporting processes make comparisons challenging and not particularly informative. Nonetheless, diagnostic yield in an undiagnosed cohort reflects the potential of an Undiagnosed Diseases Program. Further comparisons and exploration of the outcomes of Undiagnosed Diseases Programs worldwide will allow for the development and improvement of the diagnostic and research process and in turn improve the value and utility of an Undiagnosed Diseases Program.
Diabetes is associated with an increased risk for many birth defects and is likely to have an increasing impact on birth defect prevalence because of the rise in diabetes in the United States in ...recent decades. One of the first analyses in which specific birth defects were assessed for their relationship with both pregestational and gestational diabetes used data from the initial 6 years of the National Birth Defects Prevention Study. That analysis reported strong associations for pregestational diabetes with several birth defects, but few exposures among some of the less common birth defects led to unstable estimates with wide confidence intervals. Since that analysis, the study continued to collect data for another 8 years, including information on approximately 19,000 additional cases and 6900 additional controls.
Our objective was to use data from the National Birth Defects Prevention Study, the largest population-based birth defects case-control study in the United States, to provide updated and more precise estimates of the association between diabetes and birth defects, including some defects not previously assessed.
We analyzed data on deliveries from October 1997 through December 2011. Mothers of case and control infants were interviewed about their health conditions and exposures during pregnancy, including diagnosis of pregestational (type 1 or type 2) diabetes before the index pregnancy or gestational diabetes during the index pregnancy. Using logistic regression, we separately assessed the association between pregestational and gestational diabetes with specific categories of structural birth defects for which there were at least 3 exposed case infants. For birth defect categories for which there were at least 5 exposed case infants, we calculated odds ratios adjusted for maternal body mass index, age, education, race/ethnicity, and study site; for defect categories with 3 or 4 exposed cases, we calculated crude odds ratios.
Pregestational diabetes was reported by 0.6% of mothers of control infants (71 of 11,447) and 2.5% of mothers of case infants (775 of 31,007). Gestational diabetes during the index pregnancy was reported by 4.7% of mothers of control infants (536 of 11,447) and 5.3% of mothers of case infants (1,653 of 31,007). Pregestational diabetes was associated with strong, statistically significant odds ratios (range, 2.5–80.2) for 46 of 50 birth defects considered. The largest odds ratio was observed for sacral agenesis (adjusted odds ratio, 80.2; 95% confidence interval, 46.1–139.3). A greater than 10-fold increased risk was also observed for holoprosencephaly (adjusted odds ratio, 13.1; 95% confidence interval, 7.0–24.5), longitudinal limb deficiency (adjusted odds ratio, 10.1; 95% confidence interval, 6.2–16.5), heterotaxy (adjusted odds ratio, 12.3; 95% confidence interval, 7.3–20.5), truncus arteriosus (adjusted odds ratio, 14.9; 95% confidence interval, 7.6–29.3), atrioventricular septal defect (adjusted odds ratio, 10.5; 95% confidence interval, 6.2–17.9), and single ventricle complex (adjusted odds ratio, 14.7; 95% confidence interval, 8.9–24.3). For gestational diabetes, statistically significant odds ratios were fewer (12 of 56) and of smaller magnitude (range, 1.3– 2.1; 0.5 for gastroschisis).
Pregestational diabetes is associated with a markedly increased risk for many specific births defects. Because glycemic control before pregnancy is associated with a reduced risk for birth defects, ongoing quality care for persons with diabetes is an important opportunity for prevention.