Dutch demographer Dirk van de Kaa traces the phenomenon to four transformations: (A) A shift from the golden age of marriage to the dawn of a new age of cohabitation. (B) A shift from a time of “king-child” with parents to that of king-parents with one child. (C) A shift from preventive contraception, to benefit early children, to self-fulfilling contraception, to benefit parents. (D) A shift from a uniform family system to a pluralistic system of families and households, including single-parent families.
