International Clearinghouse For Birth Defects Surveillance And Research Research Articles

Gastroschisis prevalence patterns in 27 surveillance programs from 24 countries, International Clearinghouse for Birth Defects Surveillance and Research, 1980-2017.

Gastroschisis is a serious birth defect with midgut prolapse into the amniotic cavity. The objectives of this study were to evaluate the prevalence and time trends of gastroschisis among programs in the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR), focusing on regional variations and maternal age changes in the population. We analyzed data on births from 1980 to 2017 from 27 ICBDSR member programs, representing 24 countries and three regions (Europe+ (includes Iran) , Latin America, North America). Cases were identified using diagnostic codes (i.e., 756.7, 756.71, or Q79.3). We excluded cases of amniotic band syndrome, limb-body wall defect, and ruptured omphalocele. Programs provided annual counts for gastroschisis cases (live births, stillbirths, and legally permitted pregnancy terminations for fetal anomalies) and source population (live births, stillbirths), by maternal age. Overall, gastroschisis occurred in 1 of every 3268 births (3.06 per 10,000 births; 95% confidence intervals [CI]: 3.01, 3.11), with marked regional variation. European+ prevalence was 1.49 (95%CI: 1.44, 1.55), Latin American 3.80 (95%CI: 3.69, 3.92) and North American 4.32 (95%CI: 4.22, 4.42). A statistically significant increasing time trend was observed among six European+ , four Latin American, and four North American programs. Women <20 years of age had the highest prevalence in all programs except the Slovak Republic. Gastroschisis prevalence increased over time in 61% of participating programs, and the highest increase in prevalence was observed among the youngest women. Additional inquiry will help to assess the impact of the changing maternal age proportions in the birth population on gastroschisis prevalence.

A multi-program analysis of cleft lip with cleft palate prevalence and mortality using data from 22 International Clearinghouse for Birth Defects Surveillance and Research programs, 1974-2014.

Cleft lip with cleft palate (CLP) is a congenital condition that affects both the oral cavity and the lips. This study estimated the prevalence and mortality of CLP using surveillance data collected from birth defect registries around the world. Data from 22 population- and hospital-based surveillance programs affiliated with the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR) in 18 countries on live births (LB), stillbirths (SB), and elective terminations of pregnancy for fetal anomaly (ETOPFA) for CLP from 1974 to 2014 were analyzed. Prevalence and survival (survival for LB only) estimates were calculated for total and subclassifications of CLP and by pregnancy outcome. The pooled prevalence of total CLP cases was 6.4 CLP per 10,000 births. The prevalence of CLP and all of the pregnancy outcomes varied across programs. Higher ETOPFA rates were recorded in most European programs compared to programs in other continents. In programs reporting low ETOPFA rates or where there was no ascertainment of ETOPFA, the rate of CLP among LB and SB was higher compared to those where ETOPFA rates were ascertained. Overall survival for total CLP was 91%. For isolated CLP, the survival was 97.7%. CLP associated with multiple congenital anomalies had an overall survival of 77.1%, and for CLP associated with genetic/chromosomal syndromes, overall survival was 40.9%. Total CLP prevalence reported in this study is lower than estimates from prior studies, with variation by pregnancy outcomes between programs. Survival was lower when CLP was associated with other congenital anomalies or syndromes compared to isolated CLP.

Prevalence and mortality among children with anorectal malformation: A multi-country analysis.

We examined the total prevalence, trends in prevalence, and age-specific mortality among individuals with anorectal malformation (ARM) METHODS: We conducted a retrospective cohort study using data from 24 population- and hospital-based birth defects surveillance programs affiliated with the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR) from 18 countries and for births from 1974 to 2014. We estimated pooled and program-specific total prevalence per 10,000 total births. Poisson regression was used to assess time trends in prevalence from 2001 to 2012 when most programs contributed data. We calculated selected age-specific proportions of deaths, stratified by case status RESULTS: The pooled total prevalence of ARM was 3.26 per 10,000 total births (95% Confidence Interval=3.19, 3.32) for birth years 1974-2014. About 60% of cases were multiple or syndromic. Prevalence of multiple, syndromic, and stillborn cases decreased from 2001 to 2012. The first week mortality proportion was 12.5%, 3.2%, 28.3%, and 18.2% among all, isolated, multiple, and syndromic cases, respectively CONCLUSIONS: ARM is relatively rare, with multiple and syndromic cases showing decreasing prevalence during the study period. Mortality is a concern during the first week of life, and especially among multiple and syndromic cases. Our descriptive epidemiological findings increase our understanding of geographic variation in the prevalence of ARM and can be used to plan needed clinical services. Exploring factors influencing prevalence and mortality among individuals with ARM could inform future studies.

Epidemiological characteristics of congenital malformations: data from the Moscow Region register

The aim of this work is to analyze the epidemiology of congenital malformations in different populations in comparison with the data of the regional register of congenital malformations of the Moscow Region. The article provides a brief description and results of the work of international organizations that collect and analyze data on the prevalence and structure of congenital anomalies — EUROCAT (European network of population-based registries for the epidemiological surveillance of congenital anomalies) and ICBDSR (The International Clearinghouse for Birth Defects Surveillance and Research). For countries where there are no monitoring systems for congenital malformations recording, the Modell World Database of Congenital Diseases (MGDb) has been developed, which makes it possible to calculate the estimated population prevalence of congenital malformations in these regions. According to international registers, the most common groups of congenital malformations are malformations of the cardiovascular, genitourinary, central nervous systems and malformations of the extremities. To date, the epidemiological picture of the prevalence and structure of congenital malformations around the world looks stable.The article analyzes data from the population-based register of congenital malformations in the Moscow Region from 2011 to 2019, with a coverage of 83% of births in the region. The overall prevalence of congenital malformations was 25.42 per 1000 births. It is determined that the structure of congenital malformations in the Moscow Region is comparable to the data of international studies, but one should pay attention to the lower frequency of most groups of malformations, which is most likely due to insufficient registration of malformations. The Moscow Region register of congenital malformations provides relevant and qualitative data on the frequency and structure of the congenital malformations in the region, which allows, if necessary, to extrapolate obtained prevalence rates to other constituent entities of the Russian Federation as well.

Analysis of early neonatal case fatality rate among newborns with congenital hydrocephalus, a 2000-2014 multi-country registry-based study.

Congenital hydrocephalus (CH) comprises a heterogeneous group of birth anomalies with a wide-ranging prevalence across geographic regions and registry type. The aim of the present study was to analyze the early neonatal case fatality rate (CFR) and total birth prevalence of newborns diagnosed with CH. Data were provided by 25 registries from four continents participating in the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR) on births ascertained between 2000 and 2014. Two CH rates were calculated using a Poisson distribution: early neonatal CFR (death within 7 days) per 100 liveborn CH cases (CFR) and total birth prevalence rate (BPR) per 10,000 births (including live births and stillbirths) (BPR). Heterogeneity between registries was calculated using a meta-analysis approach with random effects. Temporal trends in CFR and BPR within registries were evaluated through Poisson regression modeling. A total of 13,112 CH cases among 19,293,280 total births were analyzed. The early neonatal CFR was 5.9 per 100 liveborn cases, 95% confidence interval (CI): 5.4-6.8. The CFR among syndromic cases was 2.7 times (95% CI: 2.2-3.3) higher than among non-syndromic cases (10.4% [95% CI: 9.3-11.7] and 4.4% [95% CI: 3.7-5.2], respectively). The total BPR was 6.8 per 10,000 births (95% CI: 6.7-6.9). Stratified by elective termination of pregnancy for fetal anomalies (ETOPFA), region and system, higher CFR were observed alongside higher BPR rates. The early neonatal CFR and total BPR did not show temporal variation, with the exception of a CFR decrease in one registry. Findings of early neonatal CFR and total BPR were highly heterogeneous among registries participating in ICBDSR. Most registries with higher CFR also had higher BPR. Differences were attributable to type of registry (hospital-based vs. population-based), ETOPFA (allowed yes or no) and geographical regions. These findings contribute to the understanding of regional differences of CH occurrence and early neonatal deaths.

Analysis of Mortality among Neonates and Children with Spina Bifida: An International Registry-Based Study, 2001-2012.

BackgroundMedical advancements have resulted in better survival and life expectancy among those with spina bifida, but a significantly increased risk of perinatal and postnatal mortality for individuals with spina bifida remains.ObjectivesTo examine stillbirth and infant and child mortality among those affected by spina bifida using data from multiple countries.MethodsWe conducted an observational study, using data from 24 population‐ and hospital‐based surveillance registries in 18 countries contributing as members of the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR). Cases of spina bifida that resulted in livebirths or stillbirths from 20 weeks' gestation or elective termination of pregnancy for fetal anomaly (ETOPFA) were included. Among liveborn spina bifida cases, we calculated mortality at different ages as number of deaths among liveborn cases divided by total number of liveborn cases with spina bifida. As a secondary outcome measure, we estimated the prevalence of spina bifida per 10 000 total births. The 95% confidence interval for the prevalence estimate was estimated using the Poisson approximation of binomial distribution.ResultsBetween years 2001 and 2012, the overall first‐week mortality proportion was 6.9% (95% CI 6.3, 7.7) and was lower in programmes operating in countries with policies that allowed ETOPFA compared with their counterparts (5.9% vs. 8.4%). The majority of first‐week mortality occurred on the first day of life. In programmes where information on long‐term mortality was available through linkage to administrative databases, survival at 5 years of age was 90%‐96% in Europe, and 86%‐96% in North America.ConclusionsOur multi‐country study showed a high proportion of stillbirth and infant and child deaths among those with spina bifida. Effective folic acid interventions could prevent many cases of spina bifida, thereby preventing associated childhood morbidity and mortality.

Estimation of the preventable proportion of congenital anomalies by selected risk factors in mothers: A case study in Iran.

Background: Worldwide, 1-6 percent of infants have at least one congenital anomaly that can lead to long-term consequences. This may have significant impacts on individuals, families, health-care systems, and societies. The aim of this study was to estimate the Population Attributable Fraction (PAF) of some congenital anomalies by three selected risk factors (obesity, diabetes and smoking) in the northwest of Iran and to estimate the number of preventable defects at birth in the population if we could reduce 50 percent of the exposure rate to these three risk factors at population level. Methods: The regional data on smoking, obesity, and diabetes were entered in Population Estimate of Attributable Fraction of Congenital Conditions Everywhere (PEACE) software developed by International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR). It calculates the PAF for congenital anomalies attributed to exposure to those three risk factors. Results: This study showed that main anomalies attributed to "obesity" include Spina Bifida 40.1% (95% CI: 31.7-47.7), Hydrocephaly 26.8 (95% CI: 9.3-42.3) and Anencephaly 17.4 (95% CI: 1.6-31.9). The highest attributable defect to "smoking" was Cleft lip w/out Palate 5.8% (95% CI: 4.3-7.4), whereas for "diabetes" it was Tetralogy of Fallot 33.3 (95% CI: 17.2-49.5). A similar pattern was found when assumed in the model, the impact of 50 percent reduction in the exposure to each of the risk factors on preventable cases of birth defects in the population. Conclusion: Obesity, diabetes, and smoking in women of childbearing age increased the risk of occurrence of congenital anomalies. However, obesity and diabetes had a remarkably greater impact compared to smoking. More studies are needed to investigate the role of passive smoking as a risk factor for the occurrence of birth defects.

Age-specific global epidemiology of hydrocephalus: Systematic review, metanalysis and global birth surveillance.

BackgroundHydrocephalus is a debilitating disorder, affecting all age groups. Evaluation of its global epidemiology is required for healthcare planning and resource allocation.ObjectivesTo define age-specific global prevalence and incidence of hydrocephalus.MethodsPopulation-based studies reporting prevalence of hydrocephalus were identified (MEDLINE, EMBASE, Cochrane, and Google Scholar (1985–2017)). Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Two authors reviewed abstracts, full text articles and abstracted data. Metanalysis and meta-regressions were used to assess associations between key variables. Heterogeneity and publication bias were assessed. Main outcome of interest was hydrocephalus prevalence among pediatric (≤ 18 years), adults (19–64 years), and elderly (≥ 65) patients. Annual hydrocephalus incidence stratified by country income level and folate fortification requirements were obtained (2003–2014) from the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR).ResultsOf 2,460 abstracts, 52 met review eligibility criteria (aggregate population 171,558,651). Mean hydrocephalus prevalence was 85/100,000 [95% CI 62, 116]. The prevalence was 88/100,000 [95% CI 72, 107] in pediatrics; 11/100,000 [95% CI 5, 25] in adults; and 175/100,000 [95% CI 67, 458] in the elderly. The ICBDSR-based incidence of hydrocephalus diagnosed at birth remained stable over 11 years: 81/100,000 [95% CI 69, 96]. A significantly lower incidence was identified in high-income countries.ConclusionThis systematic review established age-specific global hydrocephalus prevalence. While high-income countries had a lower hydrocephalus incidence according to the ICBDSR registry, folate fortification status was not associated with incidence. Our findings may inform future healthcare resource allocation and study.

Value of sharing and networking among birth defects surveillance programs: an ICBDSR perspective.

Birth defects (BD), also known as congenital anomalies, are structural or functional abnormalities present at birth as a result of abnormal prenatal development. Their cause can be broadly categorized as genetic, environmental, or a combination of both. It is estimated that approximately 3-6% of newborn infants worldwide are affected by BD, many of which are associated with serious morbidity, mortality, and lifelong disabilities. The International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR), founded in 1974, promotes worldwide birth defect surveillance, research, and prevention through the ongoing sharing of data, expertise, and training. In this review, we show value and contribution of BD surveillance systems in pursuing these aims. In the time of personalized medicine for many rare and common diseases, there are still massive gaps in our understanding of the causes and mechanisms of many birth defects, especially structural congenital anomalies. The main aim of the Sustainable Development Goals (SDGs), adopted by the United Nations in 2015, is to ensure healthy lives and promote well-being for all children. One specific goal is to end preventable deaths of newborns and children less than 5years of age by 2030. The SDGs also underscore the need to consider BD as a priority in the global child health agenda. It can be said that counting BD helps BD to count. By sharing data and expertise and joining in surveillance and research, BD surveillance programs can play a major role in increasing our understanding of the causes of BD, and promoting prevention.

Prevalence and Risk of Birth Defects Observed in a Prospective Cohort Study: The Hokkaido Study on Environment and Children's Health.

BackgroundPrevalence rates of all anomalies classified as birth defects, including those identified before the 22nd gestational week, are limited in published reports, including those from the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR). In our birth cohort study, we collected the data for all birth defects after 12 weeks of gestation.MethodsSubjects in this study comprised 19,244 pregnant women who visited one of 37 associated hospitals in the Hokkaido Prefecture from 2003 through 2012, and completed follow-up. All birth defects after 12 weeks of gestation, including 55 marker anomalies associated with environmental chemical exposures, were recorded. We examined parental risk factors for birth defects and the association between birth defects and risk of growth retardation.ResultsPrevalence of all birth defects was 18.9/1,000 births. The proportion of patients with birth defects delivered between 12 and 21 weeks of gestation was approximately one-tenth of all patients with birth defects. Among those with congenital malformation of the nerve system, 39% were delivered before 22 weeks of gestation. All patients with anencephaly and encephalocele were delivered before 22 weeks of gestation. We observed different patterns of parental risk factors between birth defect cases included in ISBDSR and cases not included. Cases included in ISBDSR were associated with an increased risk of preterm birth. Cases not included in ISBDSR were associated with an increased risk of being small for gestational age at term.ConclusionsData from our study complemented the data from ICBDSR. We recommend that birth defects not included in ICBDSR also be analyzed to elucidate the etiology of birth defects.

Uses, Limitations, and Validity of a Registry of Congenital Anomalies in Iran: A Critical Review.

Background and Aims Preventive strategies of congenital anomalies are basically relying on the systematic ongoing collection and analysis of data and timely dissemination of information. The aim of this paper is to briefly report a critical review of a surveillance system of congenital anomalies in a developing country, by describing the challenges and experience of the registry since it began. Methods Tabriz Registry of Congenital Anomalies (TRoCA) was mainly set up based on the guidelines provided by the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR) for data collection, coding, process, analysis, use, and evaluation of the system. Findings TRoCA has successfully achieved its main objective as a pilot model for setting up a nationwide registry of congenital anomalies in the country. The programme has too succeeded in relation to its regional objectives: epidemiological rates and data have been produced consistently for etiological investigations, methodological studies, service provision, and preventive measures for selected anomalies. Conclusions Our successful experience, as a small registry in a developing country, might be of interest and useful to practitioners, policymakers of birth defects control programmes, and mainly those willing to set up a monitoring system of congenital anomalies in similar areas.

Screening the genes

The application of genomic research to public health services in the last decades has led to more accurate and faster diagnostic tests, the development of new drugs and to the early detection of genetic disorders. But while wealthier countries have long been able to screen for the more common congenital disorders, low- and middle-income countries have been slower on the uptake. Lack of resources, lack of data on the true magnitude of the problem and lack of trained health professionals are only parts of the reason for this slow uptake. Congenital disorders can be perceived as less important than other public health problems. some countries, fears of stigma and legal or religious restrictions on abortion are barriers to screening programmes. In poorer countries, neonatal and infant mortality is mostly due to infectious diseases, and lack of antenatal care, so genetic diseases are not perceived as having enough importance for governments to allocate resources to establish genetic services, says Professor Lavinia Schuler-Faccini of the Department of Universidade Federal do Rio Grande do Sul in Porto Alegre, in Brazil. Genetics is largely perceived as extremely expensive and accessible to a minority of people. However, in poorer countries, the population also tends to have lower health education, and this frequently increases pregnancy risks. [ILLUSTRATION OMITTED] The situation is now changing. The approval of a resolution on the prevention and care of birth defects by the World Health Assembly in May 2010 and publication in 2011 of the first global report on community genetic services in low- and middle-income countries by World Health Organization (WHO) mean that genetic services could become more widely accessible. Community genetic services aim to prevent congenital disorders and genetic diseases and to provide diagnoses and counselling in the community for affected families. The WHO report highlighted some countries that have adopted prevention programmes for congenital disorders, such as Bahrain, Cyprus and the Islamic Republic of Iran, but found that congenital disorders--more commonly known as birth defects--constituted a major health problem worldwide and that there were not enough services in low- and middle-income countries to prevent and manage these conditions. Birth defects are defined by WHO as structural or functional abnormalities that are present from birth, whether recognized at birth or later. Some low- and middle-income countries--particularly in Africa, eastern Mediterranean and south-eastern Asia--combine limited prevention and care with high prevalence of particular congenital disorders, such as haemoglobinopathies; disorders that affect the way blood carries oxygen. Consanguinity--marriage between people who are related to each other--can increase inherited diseases, as can advanced maternal age at conception, which increases chromosomal trisomies such as Down syndrome. Screening and prevention programmes for genetic disorders can have other public health benefits through simple and wide-ranging interventions such as folic acid supplementation; immunization, screening and control of diabetes and obesity; and prevention of smoking initiation, according to Dr Lorenzo Botto, professor of Paediatrics at the University of Utah School of Medicine in the United States of America and chair of the executive committee of the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR). Such measures can often be implemented within existing maternal and child programmes, and in time the same mechanisms should be used to give parents access to genetic counselling on an equitable basis, according to Dr Anita Kar, director of the Interdisciplinary School of Health Sciences at the University of Pune, India. India has yet to develop best practices for genetic counselling, she says. …

Conjoined twins: A worldwide collaborative epidemiological study of the International Clearinghouse for Birth Defects Surveillance and Research

Conjoined twins (CT) are a very rare developmental accident of uncertain etiology. Prevalence has been previously estimated to be 1 in 50,000 to 1 in 100,000 births. The process by which monozygotic twins do not fully separate but form CT is not well understood. The purpose of the present study was to analyze diverse epidemiological aspects of CT, including the different variables listed in the Introduction Section of this issue of the Journal. The study was made possible using the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR) structure. This multicenter worldwide research includes the largest sample of CT ever studied. A total of 383 carefully reviewed sets of CT obtained from 26,138,837 births reported by 21 Clearinghouse Surveillance Programs (SP) were included in the analysis. Total prevalence was 1.47 per 100,000 births (95% CI: 1.32-1.62). Salient findings including an evident variation in prevalence among SPs: a marked variation in the type of pregnancy outcome, a similarity in the proportion of CT types among programs: a significant female predominance in CT: particularly of the thoracopagus type and a significant male predominance in parapagus and parasitic types: significant differences in prevalence by ethnicity and an apparent increasing prevalence trend in South American countries. No genetic, environmental or demographic significant associated factors were identified. Further work in epidemiology and molecular research is necessary to understand the etiology and pathogenesis involved in the development of this fascinating phenomenon of nature.

Bladder exstrophy: An epidemiologic study from the International Clearinghouse for Birth Defects Surveillance and Research, and an overview of the literature

Bladder exstrophy (BE) is a complex congenital anomaly characterized by a defect in the closure of the lower abdominal wall and bladder. We aimed to provide an overview of the literature and conduct an epidemiologic study to describe the prevalence, and maternal and case characteristics of BE. We used data from 22 participating member programs of the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR). All cases were reviewed and classified as isolated, syndrome, and multiple congenital anomalies. We estimated the total prevalence of BE and calculated the frequency and odds ratios for various maternal and case characteristics. A total of 546 cases with BE were identified among 26,355,094 births. The total prevalence of BE was 2.07 per 100,000 births (95% CI: 1.90-2.25) and varied between 0.52 and 4.63 among surveillance programs participating in the study. BE was nearly twice as common among male as among female cases. The proportion of isolated cases was 71%. Prevalence appeared to increase with increasing categories of maternal age, particularly among isolated cases. The total prevalence of BE showed some variations by geographical region, which is most likely attributable to differences in registration of cases. The higher total prevalence among male cases and older mothers, especially among isolated cases, warrants further attention.

Prevalence at Birth of Cleft Lip with or without Cleft Palate: Data from the International Perinatal Database of Typical Oral Clefts (IPDTOC)

As part of a collaborative project on the epidemiology of craniofacial anomalies, funded by the National Institutes for Dental and Craniofacial Research and channeled through the Human Genetics Programme of the World Health Organization, the International Perinatal Database of Typical Orofacial Clefts (IPDTOC) was established in 2003. IPDTOC is collecting case-by-case information on cleft lip with or without cleft palate and on cleft palate alone from birth defects registries contributing to at least one of three collaborative organizations: European Surveillance Systems of Congenital Anomalies (EUROCAT) in Europe, National Birth Defects Prevention Network (NBDPN) in the United States, and International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR) worldwide. Analysis of the collected information is performed centrally at the ICBDSR Centre in Rome, Italy, to maximize the comparability of results. The present paper, the first of a series, reports data on the prevalence of cleft lip with or without cleft palate from 54 registries in 30 countries over at least 1 complete year during the period 2000 to 2005. Thus, the denominator comprises more than 7.5 million births. A total of 7704 cases of cleft lip with or without cleft palate (7141 livebirths, 237 stillbirths, 301 terminations of pregnancy, and 25 with pregnancy outcome unknown) were available. The overall prevalence of cleft lip with or without cleft palate was 9.92 per 10,000. The prevalence of cleft lip was 3.28 per 10,000, and that of cleft lip and palate was 6.64 per 10,000. There were 5918 cases (76.8%) that were isolated, 1224 (15.9%) had malformations in other systems, and 562 (7.3%) occurred as part of recognized syndromes. Cases with greater dysmorphological severity of cleft lip with or without cleft palate were more likely to include malformations of other systems.

International trends of Down syndrome 1993–2004: Births in relation to maternal age and terminations of pregnancies

AbstractBACKGROUND:The aim of this study was to examine trends of Down syndrome (DS) in relation to maternal age and termination of pregnancies (ToP) in 20 registries of the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR).METHODS:Trends of births with DS (live‐born and stillborn), ToP with DS, and maternal age (percentage of mothers older than 35 years) were examined by year over a 12‐year period (1993–2004). The total mean number of births covered was 1550,000 annually.RESULTS:The mean percentage of mothers older than 35 years of age increased from 10.9% in 1993 to 18.8% in 2004. However, a variation among the different registers from 4–8% to 20–25% of mothers &gt;35 years of age was found. The total mean prevalence of DS (still births, live births, and ToP) increased from 13.1 to 18.2/10,000 births between 1993 and 2004. The total mean prevalence of DS births remained stable at 8.3/10,000 births, balanced by a great increase of ToP. In the registers from France, Italy, and the Czech Republic, a decrease of DS births and a great increase of ToP was observed. The number of DS births remained high or even increased in Canada Alberta, and Norway during the study period.CONCLUSIONS:Although an increase in older mothers was observed in most registers, the prevalence of DS births remained stable in most registers as a result of increasing use of prenatal diagnostic procedures and ToP with DS. Birth Defects Research (Part A), 2010. © 2010 Wiley‐Liss, Inc.

35th Annual Meeting of the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR)

35^th Annual Meeting of the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR)

Gastroschisis and associated defects: An international study

Our objective was to evaluate the frequency and type of malformations associated with gastroschisis in a large pool of international data, to identify malformation patterns, and to evaluate the role of maternal age in non-isolated cases. Case-by-case information from 24 registries, all members of the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR), were evaluated. After the exclusion of other abdominal wall defects cases were classified as: (a) isolated; (b) recognizable syndrome, chromosomal or not; (c) multiple congenital anomalies (MCA). Our results showed that out of 3,322 total cases 469 non-isolated cases were registered (14.1%): 41 chromosomal syndromes, 24 other syndromes, and 404 MCA. Among MCA four groups of anomalies were most frequent: CNS (4.5%), cardio-vascular (2.5%), limb (2.2%), and kidney anomalies (1.9%). No similar patterns emerged except two patterns resembling limb-body wall complex and OEIS. In both of them the gastroschisis could be however misclassified. Chromosomal trisomies and possibly non-syndromic MCA are associated with an older maternal age more than isolated cases. On consideration of our data and the most valid studies published in the literature, the best estimate of the proportion of gastroschisis associated with major unrelated defects is about 10%, with a few cases associated to recognizable syndromes. Recognized syndromes with gastroschisis seem to be so exceptional that the well documented and validated cases are worth being published as interesting case report. An appropriate case definition in etiological studies should include only isolated gastroschisis after an appropriate definition of isolated and non-isolated cases and a thorough case-by-case review.