Changes in psychological well-being across the transition to motherhood: Combining longitudinal and experience sampling methods.

Becoming a parent is a major life event associated with changes in psychological well-being. Existing research has often focused on the long-term development of trait well-being, leaving several gaps unaddressed. The current preregistered study employed three waves of intensive longitudinal data, including 7-day experience sampling data per wave, to investigate psychological well-being trajectories across the transition to motherhood. This approach provides novel, detailed insights into the timing of well-being changes (beyond traditional annual assessments), explores developments in different change indicators (mean-level, intraindividual variability, and individual differences), and various well-being components (affective, cognitive, and meaning in life) during this critical life transition. Following 161 first-time Dutch mothers from 20 weeks of pregnancy to 6 months postpartum, we observed increases in positive affect and meaning in life, along with decreases in life and relationship satisfaction that occurred between pregnancy and 2-3 months postpartum, with no significant changes afterward. In contrast, no significant changes in intraindividual variability in well-being (i.e., well-being fluctuations from moment to moment and day to day) were observed throughout the transition. There were both similarities and differences between the trajectories of trait and mean-state measures of different well-being outcomes, and additional exploratory analyses highlighted how various daily predictors (e.g., sleep quality, infant crying) became more (or less) important for mothers' well-being as they moved across the transition. The present study contributed to a better understanding of how the changes in a broad range of well-being components and other parameters unfold across the transition to motherhood. (PsycInfo Database Record (c) 2025 APA, all rights reserved).