The Fertility Database

The aim of the register

The register aims to create better opportunities for fertility research in Denmark.

Responsible authority

Statistics Denmark


Jørn K. Petersen, tel. +45 39 17 32 32, email:


The Fertility Database includes three population types: Women, men and children. Additionally, information on cohabiting couples and families with or without children can be produced based on family/marital status.
Women: All women of fertile age (the age during which women can become pregnant - that is, women aged 13-49), identified using information from the Population Statistics Register. The women were identified beginning on 1 January 1980, and as such were born during the years 1930-1968.
Men: Similarly, a population of men who were at least 13 years old had been identified using the Population Statistics Register every year since 1 January 1980. As men aged 50 or more are also becoming fathers, in principle there is no upper limit. However, very few men have children at age 60 or more. As such, in practice, the register works with an upper limit of 64 years of age.
Children: The children were primarily identified using the Population Statistics Register and Statistics Denmark’s Medical Register of Births and Deaths. The “children” were persons born from 1942 onwards, which is the first year in which the oldest women in the population were able to have children.


The Fertility Database contains a large number of variables dealing with information on demographics, occupation and income, education, family, housing and social conditions. For children, the register also contains information on their birth.
The Fertility Database also contains a number of calculated variables, such as the age of first-time parents, average number of children at a given age (called the parity) as well as time between births (called the spacing).

Accessing the data

Contact Statistics Denmark Figures are published with five year intervals


Annual, on 1 January


The Population Statistics Register, the Medical Register of Births and Deaths, the Education Classification Module, the Education Statistics Register, the Employment Classification Module, the Income Statistics Register, the Register regarding income compensating benefits, the Central Register of Buildings and Dwellings. The register also uses information from the Medical Birth Register by the Danish Health Authority.

Period covered



Lisbeth B. Knudsen. Fertility Trends in Denmark in the 1980s. A Register Based Socio-demographic Analysis of fertility Trends.
Statistiske Undersøgelser no. 44.
Fertilitetsudviklingen i Danmark i 1980'erne, Statistiske Efterretninger, Befolkning og Valg 1993:12.
Fertilitetsudviklingen i Danmark fra 1980 til 1993, Statistiske Efterretninger, Befolkning og Valg, 1997:3.
Vejledning i udtræk fra Fertilitetsdatabasen, Statistics Denmark, June 1996.