There are three important milestones in the post-war population development of the Slovak Republic. Firstly, it is the turn of fortieth and fiftieth years of 20th century, when mortality decreased substantially. Secondly, it is the period of the second half of 60s when the significant differences in the population development between the Western and Eastern part of Europe started to appear, thus, the differences between countries with democratic and non-democratic political system. Thirdly, it is the beginning of 1990s when the demographic development sharply reacted to the basic political and social changes.
After the end of the World War II, the population development in Slovakia did not differ from the main European population trends. In the second half of 60s the period of significant demographic changes started in Western Europe. The nuptiality and natality fell, the forms of the coexistence of partners started to change, the number of children born outside marriage increased, the mortality decreased and the human life began to prolong.
Such significant changes in the population development did not occur in Slovakia (similarly as in other countries of the former East block). Conversely, the population development from the post-war period had rather reinforced even more. The nuptiality and natality were continuously increasing. The mortality stagnated, however, in some age groups, mainly in case of men, it even increased. The orientation to the traditional family was demonstrated, in addition to other factors, by a lower ratio of children born outside marriage. The consequence of the existing political breakdown of Europe was the different way of the reproduction behaviour of population in particular political blocks.
The principal difference from the development in democratic countries affected all countries of the former East block. Despite the same basic features in the population development some remarkable differences between the particular countries existed and still exist. The differences are the consequence mainly of the historical, political, religious, cultural, geographical and economic aspects and conditions which significantly contributed to the formation of traditions and mentality of population in these countries and thus also to the formation of their reproduction behaviour.
From this point of view Slovakia can be characterised as a country with strong conservative traditions which appeared in the orientation to the family with a higher number of children. This tradition was partially modified by a common population area with the Czech Republic. Until the end of the 80s, Slovakia belonged to the countries with the highest natality in Europe, however, it had also a high mortality, high abortion and an unfavourable trend in the development of divorce. Moreover, the high natality, being shifted to the very beginning of the reproduction period when very young people entered the marriage and became parents without adequate life experience, contributed to the instability of the family.
From the beginning of the 90s, in Slovakia we observe significant changes in the demographic development, which reflect the actual socio-economic situation and which can be indicated as a transition to the new model of the reproduction behaviour of population. A significant decrease in nuptiality and fertility, an ongoing increasing trend in divorces, despite certain improvement an unsatisfactorily level of mortality and changes in the development of abortion and migration cause the following: ageing of population, an increasing economic burden of population, changes in the structure of families and households, increasing of the average age at marriage and the average age of parents at the time of the birth of child. The natural increase of population is diminishing. The issue whether the long-term trends are in question or whether the break point in the current demographic development is to be expected after the end of the transformation period is to be considered as a very important one.