Paper 2: EUROCAT public health indicators for congenital anomalies in Europe.

OBJECTIVE: The purpose of this article is to present the specific public health indicators recently developed by EUROCAT that aim to summarize important aspects of the public health impact of congenital anomalies in a few quantitative measures. METHODS: The six indicators are: (1) congenital anomaly perinatal mortality, (2) congenital anomaly prenatal diagnosis prevalence, (3) congenital anomaly termination of pregnancy, (4) Down syndrome livebirth prevalence, (5) congenital anomaly pediatric surgery, and (6) neural tube defects (NTD) total prevalence. Data presented for this report pertained to all cases (livebirths, fetal deaths, or stillbirths after 20 weeks of gestation and terminations of pregnancy for fetal anomaly [TOPFA]) of congenital anomaly from 27 full member registries of EUROCAT that could provide data for at least 3 years during the period 2004 to 2008. Prevalence of anomalies, prenatal diagnosis, TOPFA, pediatric surgery, and perinatal mortality were calculated per 1000 births. RESULTS: The overall perinatal mortality was approximately 1.0 per 1000 births for EUROCAT registries with almost half due to fetal and the other half due to first week deaths. There were wide variations in perinatal mortality across the registries with the highest rates observed in Dublin and Malta, registries in countries where TOPFA are illegal, and in Ukraine. The overall perinatal mortality across EUROCAT registries slightly decreased between 2004 and 2008 due to a decrease in first week deaths. The prevalence of TOPFA was fairly stable at about 4 per 1000 births. There were variations in livebirth prevalence of cases typically requiring surgery across the registries; however, for most registries this prevalence was between 3 and 5 per 1000 births. Prevalence of NTD decreased by about 10% from 1.05 in 2004 to 0.94 per 1000 in 2008. CONCLUSION: It is hoped that by publishing the data on EUROCAT indicators, the public health importance of congenital anomalies can be clearly summarized to policy makers, the need for accurate data from registries emphasized, the need for primary prevention and treatment services highlighted, and the impact of current services measured.

Paper 3: EUROCAT data quality indicators for population-based registries of congenital anomalies.

The European Surveillance of Congenital Anomalies (EUROCAT) network of population-based congenital anomaly registries is an important source of epidemiologic information on congenital anomalies in Europe covering live births, fetal deaths from 20 weeks gestation, and terminations of pregnancy for fetal anomaly. EUROCAT's policy is to strive for high-quality data, while ensuring consistency and transparency across all member registries. A set of 30 data quality indicators (DQIs) was developed to assess five key elements of data quality: completeness of case ascertainment, accuracy of diagnosis, completeness of information on EUROCAT variables, timeliness of data transmission, and availability of population denominator information. This article describes each of the individual DQIs and presents the output for each registry as well as the EUROCAT (unweighted) average, for 29 full member registries for 2004-2008. This information is also available on the EUROCAT website for previous years. The EUROCAT DQIs allow registries to evaluate their performance in relation to other registries and allows appropriate interpretations to be made of the data collected. The DQIs provide direction for improving data collection and ascertainment, and they allow annual assessment for monitoring continuous improvement. The DQI are constantly reviewed and refined to best document registry procedures and processes regarding data collection, to ensure appropriateness of DQI, and to ensure transparency so that the data collected can make a substantial and useful contribution to epidemiologic research on congenital anomalies.

Epidemiologie der letalen Missbildungen in der Schweiz. [Epidemiology of fatal abnormalities in Switzerland].

Official certificates of stillbirth and infant death are analysed in the birth cohort of 1979-81. Congenital malformations account for approx. 40% of infant mortality. Cantonal differences in malformation rates are not explained by different incidence of such malformations only, but also by differences in lethality. Incidence of Anencephaly is examined in detail.

Prenatal ultrasonographic detection of gastrointestinal obstruction: results from 18 European congenital anomaly registries.

OBJECTIVES: We evaluated the prenatal detection of gastrointestinal obstruction (GIO, including atresia, stenosis, absence or fistula) by routine ultrasonographic examination in an unselected population all over Europe. METHODS: Data from 18 congenital malformation registries in 11 European countries were analysed. These multisource registries used the same methodology. All fetuses/neonates with GIO confirmed within 1 week after birth who had prenatal sonography and were born during the study period (1 July 1996 to 31 December 1998) were included. RESULTS: There were 670 793 births in the area covered and 349 fetuses/neonates had GIO. The prenatal detection rate of GIO was 34%; of these 40% were detected < or = 24 weeks of gestation (WG). A total of 31% (60/192) of the isolated GIO were detected prenatally, as were 38% (59/157) of the associated GIO (p=0.26). The detection rate was 25% for esophageal obstruction (31/122), 52% for duodenal obstruction (33/64), 40% for small intestine obstruction (27/68) and 29% for large intestine obstruction (28/95) (p=0.002). The detection rate was higher in countries with a policy of routine obstetric ultrasound. Fifteen percent of pregnancies were terminated (51/349). Eleven of these had chromosomal anomalies, 31 multiple malformations, eight non-chromosomal recognized syndromes, and one isolated GIO. The participating registries reflect the various national policies for termination of pregnancy (TOP), but TOPs after 24 WG (11/51) do not appear to be performed more frequently in countries with a liberal TOP policy. CONCLUSION: This European study shows that the detection rate of GIO depends on the screening policy and on the sonographic detectability of GIO subgroups.

EUROCAT website data on prenatal detection rates of congenital anomalies.

The EUROCAT website www.eurocat-network.eu publishes prenatal detection rates for major congenital anomalies using data from European population-based congenital anomaly registers, covering 28% of the EU population as well as non-EU countries. Data are updated annually. This information can be useful for comparative purposes to clinicians and public health service managers involved in the antenatal care of pregnant women as well as those interested in perinatal epidemiology.

Trends in the prevalence, risk and pregnancy outcome of multiple births with congenital anomaly: a registry-based study in 14 European countries 1984-2007.

OBJECTIVE: To assess the public health consequences of the rise in multiple births with respect to congenital anomalies. DESIGN: Descriptive epidemiological analysis of data from population-based congenital anomaly registries. SETTING: Fourteen European countries. POPULATION: A total of 5.4 million births 1984-2007, of which 3% were multiple births. METHODS: Cases of congenital anomaly included live births, fetal deaths from 20 weeks of gestation and terminations of pregnancy for fetal anomaly. MAIN OUTCOME MEASURES: Prevalence rates per 10,000 births and relative risk of congenital anomaly in multiple versus singleton births (1984-2007); proportion prenatally diagnosed, proportion by pregnancy outcome (2000-07). Proportion of pairs where both co-twins were cases. RESULTS: Prevalence of congenital anomalies from multiple births increased from 5.9 (1984-87) to 10.7 per 10,000 births (2004-07). Relative risk of nonchromosomal anomaly in multiple births was 1.35 (95% CI 1.31-1.39), increasing over time, and of chromosomal anomalies was 0.72 (95% CI 0.65-0.80), decreasing over time. In 11.4% of affected twin pairs both babies had congenital anomalies (2000-07). The prenatal diagnosis rate was similar for multiple and singleton pregnancies. Cases from multiple pregnancies were less likely to be terminations of pregnancy for fetal anomaly, odds ratio 0.41 (95% CI 0.35-0.48) and more likely to be stillbirths and neonatal deaths. CONCLUSIONS: The increase in babies who are both from a multiple pregnancy and affected by a congenital anomaly has implications for prenatal and postnatal service provision. The contribution of assisted reproductive technologies to the increase in risk needs further research. The deficit of chromosomal anomalies among multiple births has relevance for prenatal risk counselling.

Paper 4: EUROCAT statistical monitoring: identification and investigation of ten year trends of congenital anomalies in Europe.

BACKGROUND: As part of EUROCAT's surveillance of congenital anomalies in Europe, a statistical monitoring system has been developed to detect recent clusters or long-term (10 year) time trends. The purpose of this article is to describe the system for the identification and investigation of 10-year time trends, conceived as a "screening" tool ultimately leading to the identification of trends which may be due to changing teratogenic factors.METHODS: The EUROCAT database consists of all cases of congenital anomalies including livebirths, fetal deaths from 20 weeks gestational age, and terminations of pregnancy for fetal anomaly. Monitoring of 10-year trends is performed for each registry for each of 96 non-independent EUROCAT congenital anomaly subgroups, while Pan-Europe analysis combines data from all registries. The monitoring results are reviewed, prioritized according to a prioritization strategy, and communicated to registries for investigation. Twenty-one registries covering over 4 million births, from 1999 to 2008, were included in monitoring in 2010.CONCLUSIONS: Significant increasing trends were detected for abdominal wall anomalies, gastroschisis, hypospadias, Trisomy 18 and renal dysplasia in the Pan-Europe analysis while 68 increasing trends were identified in individual registries. A decreasing trend was detected in over one-third of anomaly subgroups in the Pan-Europe analysis, and 16.9% of individual registry tests. Registry preliminary investigations indicated that many trends are due to changes in data quality, ascertainment, screening, or diagnostic methods. Some trends are inevitably chance phenomena related to multiple testing, while others seem to represent real and continuing change needing further investigation and response by regional/national public health authorities.

Registration of congenital anomalies in Switzerland by EUROCAT.

Since 1988 the epidemiological surveillance of congenital anomalies (malformations, chromosomal aberrations, metabolic diseases, hereditary diseases, neurosensorial defects, etc.) is carried out by the Swiss registry of EUROCAT (European Registry of Congenital Anomalies and Twins). Several Swiss cantons collaborate through their own local registry, transmitting data to the central registry in Lausanne. We present the main objectives and methods of registration and give the global prevalence rates for the main malformations for 1996 and the period 1993-1996.

Spectrum of congenital anomalies in pregnancies with pregestational diabetes.

BACKGROUND: Maternal pregestational diabetes is a well-known risk factor for congenital anomalies. This study analyses the spectrum of congenital anomalies associated with maternal diabetes using data from a large European database for the population-based surveillance of congenital anomalies. METHODS: Data from 18 population-based EUROCAT registries of congenital anomalies in 1990-2005. All malformed cases occurring to mothers with pregestational diabetes (diabetes cases) were compared to all malformed cases in the same registry areas to mothers without diabetes (non-diabetes cases). RESULTS: There were 669 diabetes cases and 92,976 non diabetes cases. Odds ratios in diabetes pregnancies relative to non-diabetes pregnancies comparing each EUROCAT subgroup to all other non-chromosomal anomalies combined showed significantly increased odds ratios for neural tube defects (anencephaly and encephalocele, but not spina bifida) and several subgroups of congenital heart defects. Other subgroups with significantly increased odds ratios were anotia, omphalocele and bilateral renal agenesis. Frequency of hip dislocation was significantly lower among diabetes (odds ratio 0.15, 95% CI 0.05-0.39) than non-diabetes cases. Multiple congenital anomalies were present in 13.6 % of diabetes cases and 6.1 % of non-diabetes cases. The odds ratio for caudal regression sequence was very high (26.40,95% CI 8.98-77.64), but only 17% of all caudal regression cases resulted from a pregnancy with pregestational diabetes. CONCLUSIONS: The increased risk of congenital anomalies in pregnancies with pregestational diabetes is related to specific non-chromosomal congenital anomalies and multiple congenital anomalies and not a general increased risk.

Prenatal detection of congenital renal malformations by fetal ultrasonographic examination: an analysis of 709,030 births in 12 European countries.

The study was performed to evaluate the prevalence of prenatal ultrasound diagnoses for renal anomalies in 20 registries of 12 European countries, and to compare the different prenatal scanning policies. Standardized data were acquired from 709,030 livebirths, stillbirths, and induced abortions during the study period of 2.5 years and transmitted for central analysis. At least one renal malformation was diagnosed in 1130 infants and fetuses. Prenatal diagnosis (PD) was given in 81.8% of all cases, 29% of these pregnancies were terminated. The highest detection rate was reported for unilateral multicystic dysplastic kidneys with 97% (102/105). An early diagnosis was documented for exstrophy of bladder at a mean gestational age of 18.5 weeks. Dilatations of the upper urinary tract were seen late in pregnancy at 28.3 weeks. Terminations of pregnancies (TOP) were performed in 67% (58/86) of the detected bilateral renal agenesis/dysgenesis, but only 4% of the unilateral multicystic dysplastic renal malformations (4/102). In about 1/3 of the cases, renal malformations are within the category of associated malformations, which include multiple non-syndromal malformations, chromosomal aberrations, and non-chromosomal syndromes. Renal malformations were detected in 2/3 of the associated category by the first prenatal ultrasound scan. Detection rates vary in the different countries of the European community due to diverse policies, ethical, and religious background. Countries with no routine ultrasound show the lowest rates in detection, and termination of pregnancy. Prenatally detected renal malformations should result in a careful examination for further anomalies. Prenatal ultrasound fulfills the needs of screening examinations and is a good tool in detecting lethal and severe renal malformations.

Seasonality of congenital anomalies in Europe.

BACKGROUND: This study describes seasonality of congenital anomalies in Europe to provide a baseline against which to assess the impact of specific time varying exposures such as the H1N1 pandemic influenza, and to provide a comprehensive and recent picture of seasonality and its possible relation to etiologic factors. METHODS: Data on births conceived in 2000 to 2008 were extracted from 20 European Surveillance for Congenital Anomalies population-based congenital anomaly registries in 14 European countries. We performed Poisson regression analysis encompassing sine and cosine terms to investigate seasonality of 65,764 nonchromosomal and 12,682 chromosomal congenital anomalies covering 3.3 million births. Analysis was performed by estimated month of conception. Analyses were performed for 86 congenital anomaly subgroups, including a combined subgroup of congenital anomalies previously associated with influenza. RESULTS: We detected statistically significant seasonality in prevalence of anomalies previously associated with influenza, but the conception peak was in June (2.4% excess). We also detected seasonality in congenital cataract (April conceptions, 27%), hip dislocation and/or dysplasia (April, 12%), congenital hydronephrosis (July, 12%), urinary defects (July, 5%), and situs inversus (December, 36%), but not for nonchromosomal anomalies combined, chromosomal anomalies combined, or other anomalies analyzed. CONCLUSION: We have confirmed previously described seasonality for congenital cataract and hip dislocation and/or dysplasia, and found seasonality for congenital hydronephrosis and situs inversus which have not previously been studied. We did not find evidence of seasonality for several anomalies which had previously been found to be seasonal. Influenza does not appear to be an important factor in the seasonality of congenital anomalies.

Imaging findings in fetal diaphragmatic abnormalities.

Imaging plays a key role in the detection of a diaphragmatic pathology in utero. US is the screening method, but MRI is increasingly performed. Congenital diaphragmatic hernia is by far the most often diagnosed diaphragmatic pathology, but unilateral or bilateral eventration or paralysis can also be identified. Extralobar pulmonary sequestration can be located in the diaphragm and, exceptionally, diaphragmatic tumors or secondary infiltration of the diaphragm from tumors originating from an adjacent organ have been observed in utero. Congenital abnormalities of the diaphragm impair normal lung development. Prenatal imaging provides a detailed anatomical evaluation of the fetus and allows volumetric lung measurements. The comparison of these data with those from normal fetuses at the same gestational age provides information about the severity of pulmonary hypoplasia and improves predictions about the fetus's outcome. This information can help doctors and families to make decisions about management during pregnancy and after birth. We describe a wide spectrum of congenital pathologies of the diaphragm and analyze their embryological basis. Moreover, we describe their prenatal imaging findings with emphasis on MR studies, discuss their differential diagnosis and evaluate the limits of imaging methods in predicting postnatal outcome.

Major congenital anomalies in babies born with Down syndrome: a EUROCAT population-based registry study.

Previous studies have shown that over 40% of babies with Down syndrome have a major cardiac anomaly and are more likely to have other major congenital anomalies. Since 2000, many countries in Europe have introduced national antenatal screening programs for Down syndrome. This study aimed to determine if the introduction of these screening programs and the subsequent termination of prenatally detected pregnancies were associated with any decline in the prevalence of additional anomalies in babies born with Down syndrome. The study sample consisted of 7,044 live births and fetal deaths with Down syndrome registered in 28 European population-based congenital anomaly registries covering seven million births during 2000-2010. Overall, 43.6% (95% CI: 42.4-44.7%) of births with Down syndrome had a cardiac anomaly and 15.0% (14.2-15.8%) had a non-cardiac anomaly. Female babies with Down syndrome were significantly more likely to have a cardiac anomaly compared to male babies (47.6% compared with 40.4%, P < 0.001) and significantly less likely to have a non-cardiac anomaly (12.9% compared with 16.7%, P < 0.001). The prevalence of cardiac and non-cardiac congenital anomalies in babies with Down syndrome has remained constant, suggesting that population screening for Down syndrome and subsequent terminations has not influenced the prevalence of specific congenital anomalies in these babies.

Use of asthma medication during pregnancy and risk of specific congenital anomalies: A European case-malformed control study.

BACKGROUND: Pregnant women with asthma need to take medication during pregnancy. OBJECTIVE: We sought to identify whether there is an increased risk of specific congenital anomalies after exposure to antiasthma medication in the first trimester of pregnancy. METHODS: We performed a population-based case-malformed control study testing signals identified in a literature review. Odds ratios (ORs) of exposure to the main groups of asthma medication were calculated for each of the 10 signal anomalies compared with registrations with nonchromosomal, nonsignal anomalies as control registrations. In addition, exploratory analyses were done for each nonsignal anomaly. The data set included 76,249 registrations of congenital anomalies from 13 EUROmediCAT registries. RESULTS: Cleft palate (OR, 1.63; 95% CI, 1.05-2.52) and gastroschisis (OR, 1.89; 95% CI, 1.12-3.20) had significantly increased odds of exposure to first-trimester use of inhaled β2-agonists compared with nonchromosomal control registrations. Odds of exposure to salbutamol were similar. Nonsignificant ORs of exposure to inhaled β2-agonists were found for spina bifida, cleft lip, anal atresia, severe congenital heart defects in general, or tetralogy of Fallot. None of the 4 literature signals of exposure to inhaled steroids were confirmed (cleft palate, cleft lip, anal atresia, and hypospadias). Exploratory analyses found an association between renal dysplasia and exposure to the combination of long-acting β2-agonists and inhaled corticosteroids (OR, 3.95; 95% CI, 1.99-7.85). CONCLUSIONS: The study confirmed increased odds of first-trimester exposure to inhaled β2-agonists for cleft palate and gastroschisis and found a potential new signal for renal dysplasia associated with combined long-acting β2-agonists and inhaled corticosteroids. Use of inhaled corticosteroids during the first trimester of pregnancy seems to be safe in relation to the risk for a range of specific major congenital anomalies.

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Primary ciliary dyskinesia (PCD) is an autosomal recessive disease with an incidence estimated between 1:2,000 and 1:40,000. Ciliated epithelia line the airways, nasal and sinus cavities, Eustachian tube and fallopian tubes. Congenital abnormalities of ciliary structure and function impair mucociliary clearance. As a consequence, patients present with chronic sinopulmonary infections, recurrent glue ear and female subfertility. Similarities in the ultrastructure of respiratory cilia, nodal cilia and sperm result in patients with PCD also presenting with male infertility, abnormalities of left-right asymmetry (most commonly situs inversus totalis) and congenital heart disease. Early diagnosis is essential to ensure specialist management of the respiratory and otological complications of PCD. Diagnostic tests focus on analysis of ciliary function and electron microscopy structure. Analysis is technically difficult and labour intensive. It requires expertise for interpretation, restricting diagnosis to specialist centres. Management is currently based on the consensus of experts, and there is a pressing need for randomised clinical trials to inform treatment.