The decomposition of factors impacting fertility change in the Czech Republic between the years 1986 and 2010 showed that the decrease in fertility level and the increase in illegitimacy ratio was realated to the rise of the proportion of unmarried women. The method of logistic regression documented that nonmarital births occurred among younger low educated mothers where children were mostly of the first birth order.
Births to unmarried women without a reported father were at risk of being stillbirth or low birthweight.