Changes in the incidence of Down syndrome in Sweden during 1968-1982
Human Genetics
|February 1, 1986
Abstract:
A continuous increase in the incidence of Down syndrome in Sweden was noted during 1979-1981. This increase mainly occurred among children of younger mothers and was more pronounced for the males than for the females. There was no evidence of a significant seasonal variation, increased frequency of prematurely born children, or decrease in the number of cases aborted after prenatal diagnosis. An analysis of the whole 15-year period indicates that the incidence of Down syndrome has increased slowly in both sexes, and that there might have been a superimposed cyclic variation limited to the males.
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