Change in toddlers’ cortisol activity during a year in childcare. Associations with childcare quality, child temperament, well-being and maternal education

The study investigates changes in cortisol levels in toddlers over the course of a year in kindergarten, and how this level relates to the quality of kindergarten, the temperament of the children, well-being in kindergarten and the mothers’ level of education. The researchers focus specifically on understanding what factors contribute to increased cortisol levels in toddlers in kindergarten, and how these levels can indicate the children’s experiences of stress in this context.

The study found that evening cortisol levels increased throughout the year, which may indicate an accumulation of stress in the toddlers. Afternoon cortisol levels remained stable, but were higher than morning cortisol levels in September and January, and only slightly lower in June. In addition, there was a correlation between high levels of well-being in kindergarten and lower total cortisol activity, as well as a minor increase in evening cortisol levels throughout the year. Less active children appeared to accumulate more stress during the day, as shown by higher evening cortisol levels. The findings suggest that time in kindergarten can be demanding for toddlers, even after attending kindergarten for a long time.

Cortisol levels were measured through saliva samples collected from 156 toddlers (81 girls, 56 boys) at three points in time (morning, afternoon and evening) during the course of a year in kindergarten. Samples were collected in September, January and June. Data on kindergarten quality, the children’s temperament, well-being and the mothers’ education were also collected and analysed in relation to cortisol levels.

Nystad, K., Drugli, M. B., Lydersen, S., Lekhal, R. & Buøen, E. S. (2022). Change in toddlers’ cortisol activity during a year in childcare. Associations with childcare quality, child temperament, well-being and maternal education. Stress, 25(1), 156–165