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- Cocchi, Guido, et al.
(författare)
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International Trends of Down Syndrome 1993-2004 : Births in Relation to Maternal Age and Terminations of Pregnancies
- 2010
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Ingår i: Birth defects research. Clinical and molecular teratology. - : Wiley. - 1542-0752 .- 1542-0760. ; 88:6, s. 474-479
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: 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 >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.
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| 2. |
- Greenlees, Ruth, et al.
(författare)
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Paper 6: EUROCAT Member Registries: Organization and Activities
- 2011
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Ingår i: Birth Defects Research Part C: Embryo Today: Reviews. - : Wiley. - 1542-975X. ; 91:Suppl. 1, s. 51-100
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Forskningsöversikt (refereegranskat)abstract
- BACKGROUND: EUROCAT is a network of population-based congenital anomaly registries providing standardized epidemiologic information on congenital anomalies in Europe. There are three types of EUROCAT membership: full, associate, or affiliate. Full member registries send individual records of all congenital anomalies covered by their region. Associate members transmit aggregate case counts for each EUROCAT anomaly subgroup by year and by type of birth. This article describes the organization and activities of each of the current 29 full member and 6 associate member registries of EUROCAT. METHODS: Each registry description provides information on the history and funding of the registry, population coverage including any changes in coverage over time, sources for ascertaining cases of congenital anomalies, and upper age limit for registering cases of congenital anomalies. It also details the legal requirements relating to termination of pregnancy for fetal anomalies, the definition of stillbirths and fetal deaths, and the prenatal screening policy within the registry. Information on availability of exposure information and denominators is provided. The registry description describes how each registry conforms to the laws and guidelines regarding ethics, consent, and confidentiality issues within their own jurisdiction. Finally, information on electronic and web-based data capture, recent registry activities, and publications relating to congenital anomalies, along with the contact details of the registry leader, are provided. CONCLUSIONS: The registry description gives a detailed account of the organizational and operational aspects of each registry and is an invaluable resource that aids interpretation and evaluation of registry prevalence data. Birth Defects Research (Part A) 91: S51-S100, 2011. (C) 2011 Wiley-Liss, Inc.
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| 3. |
- Leoncini, Emanuele, et al.
(författare)
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How Valid Are the Rates of Down Syndrome Internationally? : Findings from the International Clearinghouse for Birth Defects Surveillance and Research
- 2010
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Ingår i: American Journal of Medical Genetics, Part A. - : Wiley. - 1552-4825 .- 1552-4833. ; 152A:7, s. 1670-1680
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Tidskriftsartikel (refereegranskat)abstract
- Rates of Down syndrome (DS) show considerable international variation, but a systematic assessment of this variation is lacking. The goal of this study was to develop and test a method to assess the validity of DS rates in surveillance programs, as an indicator of quality of ascertainment. The proposed method compares the observed number of cases with DS (livebirths plus elective pregnancy terminations, adjusted for spontaneous fetal losses that would have occurred if the pregnancy had been allowed to continue) in each single year of maternal age, with the expected number of cases based on the best-published data on rates by year of maternal age. To test this method we used data from birth years 2000 to 2005 from 32 surveillance programs of the International Clearinghouse for Birth Defects Surveillance and Research. We computed the adjusted observed versus expected ratio (aOE) of DS birth prevalence among women 25-44 years old. The aOE ratio was close to unity in 13 programs (the 95% confidence interval included 1), above 1 in 2 programs and below 1 in 18 programs (P < 0.05). These findings suggest that DS rates internationally can be evaluated simply and systematically, and underscores how adjusting for spontaneous fetal loss is crucial and feasible. The aOE ratio can help better interpret and compare the reported rates, measure the degree of under- or over-registration, and promote quality improvement in surveillance programs that will ultimately provide better data for research, service planning, and public health programs.
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