Parents complete questionnaires including questions on:
- smoking habits;
- alcohol consumption;
- recreational drug use;
- use of folic acid;
- infections and vaccinations during pregnancy (e.g. COVID-19);
- maternal BMI;
- medication use;
- chronic illnesses;
- assisted conception;
- maternal and paternal education and occupation;
- socio-economic status;
- prenatal screening and diagnostics.
In addition, data from community pharmacies are used to collect data on medication dispensed in the period from 3 months before and during pregnancy. After the information of the pharmacy is received, the mother is asked, via the questionnaire, whether she has actually taken the medication and if she has taken any over-the-counter medication. The response rate to the questionnaire is about 80%. General statistics are available from the Central Bureau of Statistics (CBS). No information on non-malformed infants is collected. Also, no biomaterials are being collected by EUROCAT NNL.