Depression during pregnancy occurs frequently and selective serotonin reuptake inhibitors (SSRIs) are often the drug of choice when treating pregnant women. Most published studies found no increased risks of congenital malformations in association with SSRIs, but there are reports of various malformations for SSRIs as a group and for specific SSRIs. To assess potential adverse effects of SSRIs as one group may be questioned because of their dissimilarities and very large datasets are needed when studying specific SSRIs. The national health and population registers in the Nordic countries offer excellent opportunities to assess long term effects of exposure during fetal life. As each of the Nordic countries is small, collaborative studies including information from all the Nordic countries are warranted to fully understand risks associated with exposure to antidepressants in fetal life.