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Advance maternal age - risk factor for low birhtweight.

OBJECTIVE
To determinate correlation between childbearing postponement and low birthweight prevalence in Czech population.


DESIGN
Population study.


METHODS
Year books of Czech Statistical Office from 1990 to 2015 were used as sources of data. Analysis was done by simple linear regression method.


RESULTS
The proportion of children borned by women older than 35 years have rised from 4% to 21% from 1990 to 2015. In the same time the percentage of low birthweight have increased from 5,7 do 7,6. The coefficient of determination, which shows the ratio of explained variability to common variability of this ratio, reach R2 = 0,88. Coclusion: The enlargement of life-borned low birthweight children is owing by 88% on account of childbearing postponement.