The Montreal Antenatal Well-Being Study (MAWS): a prospective longitudinal study of perinatal mental health

Objective: This prospective longitudinal cohort aims to identify biological, psychological, and social factors that contribute to maternal perinatal mental health, family well-being, and child development. Method: Pregnant individuals (N=1130) were recruited between 8-20 gestation weeks. Questionnaire data were collected through a web-based platform together with biosamples for genetic analysis. Baseline characteristics of the cohort are described. A Bayesian model explored potential pandemic-associated changes in baseline maternal mental health symptoms throughout recruitment. Results: At baseline, 28.3% and 11.6% of pregnant participants reported clinically significant symptoms of anxiety (Spielberger Trait Anxiety Inventory ≥ 40) or depression (Edinburgh Postnatal Depression Scale ≥ 13). The onset of the COVID-19 pandemic was associated with increased likelihood of elevated scores on brief screening instruments for anxiety and depression. There was insufficient evidence for such effects using other screening tools. Conclusion(s): We further highlight anxiety and depression as common complications of pregnancy but find a modest impact of the pandemic on mental health within this cohort. Leveraging the unique data collected through this study we seek to inform screening practices and health policy to improve the well-being of mothers and families.