Abstract

Abstract
Raising Twins: Studies on Maternal Well-Being and Characterization of Twins’ Early Brain and Behavioural Development
Sutton Smith, Ph.D.
Concordia University, 2023
The early environment which includes the in-utero and the postnatal period, plays a role in brain and behavioural development. Twin designs provide us with the unique opportunity to study non-shared environmental contributions while controlling for genetic effects and the shared environment. However, there is some evidence to suggest that parents of twins also face unique stressors. The main objective of this thesis is to better understand maternal mental health in mothers of twins and behavioural and preliminary brain outcomes in the twins. The first chapter is a meta-analysis that included 14 articles to quantify the differences in depressive symptoms in mothers of singletons and mothers of twins. The second chapter is a latent class analysis in mothers of twins three, six, and nine months postpartum. We identified three possible trajectories for mothers of twins’ depressive symptoms. We tested the hypothesis that mothers with a trajectory of increasing symptoms over time were not associated with behavioural outcomes in the twins at 24 months. The third chapter of this thesis is a case report paper about five families that agreed to participate in a neuroimaging study when the twins were four years old. We showed the feasibility of doing brain imaging in twins at the preschool age and obtained data regarding the twins’ experiences in the MRI. This dissertation highlights the need for additional resources for mothers of twins. Additionally, the resources should be offered more than immediately postpartum. We conclude that neuroimaging in a pediatric population of identical twins is feasible.
Keywords: Twins, mental health, maternal, brain development, behaviour, longitudinal cohort, depression