The main objective of this study is interested primarily in the inter-individual diversity in fertility according to the parity distribution of women reproduction in Czech Republic and Slovakia. The authors identify a sharp decline in the concentration of reproduction during the 20th century at very low levels. It was primarily the result of a very low childlessness with combination of significant domination of the two-child family model. This trend has reversed for the most recent cohorts. It appears that this development mainly triggered by pluralization of reproductive behavior. The youngest cohort tends to increase childlessness as well as increase the proportion of women with only one child. The growing concentration of reproduction suggests that future society in Czech Republic and Slovakia should not simply focus on "average" women (or mother) but should take into an account a wide spectrum of orientations and life strategies.