Couple commitment remains a crucial yet understudied aspect of couple dynamics, with few studies examining its trajectories during the transition to parenthood (TTP). Although romantic attachment (anxiety and avoidance) is associated with couple commitment during transition to parenthood, little is known about protective factors, such as partner support, that may buffer against changes in commitment for both parents. The goal of this study was to examine trajectories of two couple commitment modes (optimal and undercommitment) in both parents and to explore whether partner support moderated the associations between attachment insecurities and commitment. In a longitudinal dyadic study of 211 couples of first-time parents, we assessed attachment insecurities during pregnancy, perceived partner support at 4 months postpartum, and couple optimal commitment and undercommitment during pregnancy, at 4, 8, and 12 months postpartum. Results from dyadic latent growth curve analyses revealed that partners higher in attachment anxiety showed a steadier decline in optimal commitment, whereas mothers higher in attachment anxiety demonstrated a slower increase in undercommitment over time. Partners paired with a more anxiously attached mother showed both a greater increase in undercommitment and a sharper decline in optimal commitment over time. Mothers paired with a more anxiously attached partner exhibited a slower but more persistent increase in their own undercommitment over time. Higher perceived partner support was associated with a slower decline in both parents' own optimal commitment and a slower increase in their own undercommitment trajectories over time. Moderation effects were also found, and the implications of these findings are discussed. (PsycInfo Database Record (c) 2026 APA, all rights reserved).
Gingras et al. (Mon,) studied this question.