Fertility, female labor supply and family policies.

Summary This thesis investigates the impact of the number of children and social interactions on mothers' labor supply. To determine whether the link between number of children and mothers' labor supply is causal, we use two random events that affect the number of children: having two elders of the same sex and twin births of rank two. The results suggest that having more than two children decreases mothers' labor force participation by 20 points and the number of hours worked by employed mothers by 2 hours per week. We then analyze how the institutional context alters the effect of the number of children on mothers' labor force participation. First, we find that before July 1994, when the Allocation parentale d'éducation was intended for parents with three or more children, having more than two children significantly reduced mothers' labor force participation. After the extension of the system to mothers of two children, this is no longer the case and the negative effect of having a second child on their activity is increased. Second, our results indicate that in departments where access to kindergarten for two-year-olds is low, having more than two children has a significantly negative effect on the activity of mothers. On the contrary, the effect is insignificant in departments where access is high. Finally, we examine the effect of neighborhood social interactions on mothers' activity. By mobilizing different sources of exogenous variation in the activity of close neighbors, we find that the activity of neighbors positively affects the individual participation of a mother.