Main characteristics of Hungarian twin and multiple births in official statistics.

Since 1876, statistical data on twin and multiple (TAM) births and deliveries have been registered in Hungary. Although there were some years during this 138-year period when twin births and deliveries were left out of the statistics, the trends can be followed, except for the period of World War II. The trends of twinning over the past four decades are summarized in this article, relying on official statistical data since 1970. Notably, the TAM birth rate rose following the Act CLIV of 1997 on Health. The Act provided state support for assisted reproductive treatments (ART), which spectacularly increased the ratio of twins - and especially of triplets - among live births. The trend has turned around since 2009-2010, and a decreasing era of TAM births seems to have begun. This article discusses some of the main and most interesting findings connected with TAM births, including twinning rates associated with different age groups, educational level, and actual place of residence by mothers, and the number of previous pregnancies of the mother. Ratios of live born males compared with live born females, lengths and weights at birth both among twins and singletons, and infant mortality rates have been calculated from the data. Twinning rates are higher in the western counties, the capital and its suburbs, and lower in the eastern counties.