The International Statistical Institute (ISI) established the World Fertility Survey program in 1972 with funding from UNFPA, USAID and the UK Overseas Development Administration. The surveys are nationally representative and generally include both a household and an individual (female) component. There were 42 WFS conducted in developing countries. Surveys were carried out by a national agency, often the statistical office. The surveys covered reproductive health, household characteristics such as family composition, marital status. Often surveys included additional topics such as water and sanitation, mortality, economic status, assets, religion and race. In addition, there were 20 WFS conducted in developed countries - these surveys used a set of instruments modified from those used for the developing countries. Portugal used these instruments but received technical and financial assistance from the developing country program. This information about the World Fertility Survey program comes from the Dynamic Data Base: Catalog of Survey Data Files by the International Statistical Institute, Voorburg, Netherlands, 1990.
Currently the data for developing countries are available through the Office of Population Research at Princeton University.