Perinatal mental health is an umbrella term that encompasses various disorders, such as depression, anxiety, obsessive-compulsive disorders, post-traumatic stress disorder (PTSD), and postpartum psychosis. The reported prevalence of those conditions varies greatly, however, depending on variation in settings, sources of data, instruments and definitions used, research designs and study populations. Overall, these disorders affect a significant number of women with debilitating and potentially life-threatening consequences both for parents and for their children, including a significant risk of maternal suicide after childbirth. In fact, in Norway and the United Kingdom, peripartum suicide is the leading indirect cause of maternal death in the first year after childbirth, while in Sweden four women take their own lives every year during the postpartum period.
The Nordic countries, Denmark, Finland, Iceland, Norway and Sweden, have developed a unique constellation of free health care and universal screening programs, all provided by primary health care systems and accessed by the vast majority of pregnant women in the region. Because all women who actively seek help can access the programs, all relevant information about the entire female population is available in national registers covering health care information as well as socioeconomic and partner status, among other data points. Such high-quality, nationwide, population-based sources of data and the possibility of linking individual data between them uniquely position the Nordic countries to fill current gaps in evidence on perinatal mental health.
In recent decades, considerable efforts have been made to also establish large, longitudinal pregnancy and birth cohorts. The Nordic countries are at the forefront of those efforts, namely with the Danish National Birth Cohort, the FinnBrain Birth Cohort Study, the Icelandic SAGA cohort, the Norwegian MoBa and Ahus Birth Cohort study, and the Swedish BASIC and Mom2B studies. Those cohort studies have provided some of the largest data sets focused on perinatal mental health at the international scale. The large sample sizes, long follow-up periods, multiple measurement points, large geographic coverage, biological sampling, and the possibility of linking data to national registries make those studies uniquely valuable.
Such databases, besides facilitating the study of the prevalence of perinatal mental disorders and its fluctuations over time provide the opportunity to prospectively test etiological hypotheses and to generate comprehensive suggestions about the underlying causal mechanisms behind perinatal mental health conditions. They may also aid the deep phenotyping of individuals that might allow for the development of more precise disease classification systems. Another obvious strength is their large sample sizes, which allows studying relatively rare risk factors and disorders as well as gene-environment interactions.
Sources of data from the Nordic countries have already contributed substantially to the evidence base on perinatal mental health (link to the article). Beyond that, the data also stand to guide future research examining background, biological and environmental factors and to ultimately aid in the early identification of groups at risk for psychiatric disorders following childbirth. □