Chapter 1 Stability in Mothers’ Work Hours in Early Childhood and Children’s Achievement in Kindergarten

Abstract Past studies suggest that full-time maternal employment may be negatively related to children’s cognitive development. Most studies measure maternal employment at one time point, while mothers’ work hours may not be stable during early childrearing years. Using data from the 2001 Early Childhood Longitudinal Study – Birth Cohort (N ≈ 6,500), the authors examine stability in mothers’ work hours across four waves when children are 9 and 24 months old, in preschool, and in kindergarten, mothers’ background characteristics associated to it, and its link to child cognitive development. Results show that the majority of mothers change work hours across the four waves. Analysis using multinomial logistic regression models suggests that mothers’ older age, fewer children, and higher household income are related to working full time at all four waves compared to varying work hours across the waves; more children and less than high school completion are related to staying home at all four waves; and mothers’ older age, being White, no change in partnership status, and holding a college degree are related to working part time at all four waves. Compared to mothers’ changing work hours, mothers’ stable work hours, full time or part time, at all four waves is related to children’s better reading, math, and cognitive scores in kindergarten, whereas mothers’ staying home at all four waves is negatively related to these scores. These associations disappear when background characteristics are controlled for in ordinary least squares regression models. These findings underscore the role of background characteristics in shaping both mothers’ stable employment and children’s cognitive development.