Explanations of the fertility crisis in modern societies: a search for commonalities.

Near-global fertility decline began in the 1960s, and from the 1980s an increasing number of European countries and some Asian ones achieved very low fertility (total fertility below 1.5) with little likelihood of completed cohort fertility reaching replacement level. Earlier theory aiming at explaining this phenomenon stressed the incompatibility between post-industrial society and behaviour necessary for population replacement. Recent theory has been more specific, often concentrating on the current Italian or Spanish situations or on the contrast between them and the situation in either Scandinavia or the English-speaking countries, or both. Such an approach ignores important evidence, especially that from German-speaking populations. The models available concentrate on welfare systems and family expenses, omitting circumstances that may be unique to individual countries or longer-term factors that may be common to all.