The prevalence of Down syndrome was studied among all live births occurring between 1989 and 1991 in the California counties monitored by the California Birth Defects Monitoring Program.
Objectives of this study were :
1) to calculate adjusted prevalence rates and quinquennial maternal age-specific risk rates of Down syndrome after adjusting for elective abortion of prenatally diagnosed fetuses ; 2) to estimate the impact of prenatal diagnosis and subsequent elective abortion of affected fetuses on the observed prevalence of Down syndrome ; and 3) to examine sex ratios among liveborn infants and fetuses with Down syndrome.
The racial/ethnic diversity and large size of the population allowed the data to be stratified into five racial categories-Hispanics, whites, Asians, blacks, and others.
For the period 1989-1991, the observed prevalence of Down syndrome was 1.13 per 1,000 live births, and the adjusted total prevalence, which took into account the termination of affected pregnancies following prenatal diagnosis, was 1.53 per 1,000 live births.
In a comparison of quinquennial maternal age-specific risk rates of Down syndrome by race, Hispanics and whites were the only groups with rates that differed significantly from each other, with Hispanics exhibiting higher rates at maternal ages under 40 years.
The overall reduction in live births with Down syndrome in 1989-1991 that could be attributed to prenatal diagnosis and elective abortion of affected fetuses was 25. (...)
Mots-clés Pascal : Mongolisme, Epidémiologie, Prévalence, Age mère, Diagnostic, Prénatal, Race, Ethnie, Sex ratio, Nourrisson, Homme, Californie, Etats Unis, Amérique du Nord, Amérique, Trisomie, Aneuploïdie, Aberration chromosomique, Chromosome G21, Maladie congénitale
Mots-clés Pascal anglais : Down syndrome, Epidemiology, Prevalence, Maternal age, Diagnosis, Prenatal, Race, Ethnic group, Sex ratio, Infant, Human, California, United States, North America, America, Trisomy, Aneuploidy, Chromosomal aberration, Chromosome G21, Congenital disease
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0180921
Code Inist : 002B23B. Création : 21/05/1997.