Data resources

We use data from national health registries, national quality registries and other nationwide databases in Denmark, Finland, Norway and Sweden.

These data have been linked at an individual level using the unique national identity number assigned to each resident in the Nordic countries. The identity numbers have been replaced with study numbers in the dataset, and no researcher has access to them.

The CoNARTaS cohort consists of around 7 850 000 children, hereby 170 000 children conceived by ART, as well as their mothers (4 130 000 mothers in total and 127 000 mothers after ART) in Denmark (1994–2014), Finland (1990– 2014), Norway (1984–2015), and Sweden (1985–2015).

List of included registries:

Denmark
From the Danish Health Data Authority:
In Vitro Fertilisation Register
Medical Birth Register
National Patient Register
National Prescription Registry
Cause of Death Register
Cancer Registry

From Statistics Denmark:
Central Population Register

Norway
From the Norwegian Institute of Public Health:
Medical Birth Registry of Norway
Cancer Registry of Norway
Norwegian Cause of Death Registry
Norwegian Patient Registry
Norwegian Prescribed Drug Registry 

From Statistics Norway:
National Population Register
National Education Database

Finland
From THL:
Medical Birth Register
Care Register for Health Care (previously named Hospital Discharge Register)
Register of Congenital malformations

From Finnish Cancer Registry:
Cancer Register 

From Statistics Finland:
Cause of Death Register