We study the causal effects of motherhood on labour market outcomes in Latin America by adopting an event study approach around the birth of the first child based on panel data from national household surveys for Chile, Mexico, Peru, and Uruguay. We show that motherhood not only reduces women’s employment but also implies changes in their occupational structure towards time-flexible, yet more vulnerable, forms of employment: part-time jobs, self-employment and informal work. Additionally, we provide suggestive evidence for 18 Latin American countries that gender norms and family policies shape the demand for flexibility that arises with the arrival of children. Countries that hold more conservative views regarding women’s role within the family or with less generous family policies show larger gaps in labour market outcomes between mothers and childless women.