It was found that the probability of mothers being employed in the formal job market rises gradually until the moment of maternity leave, and it falls after that. Furthermore, the decline in employment begins immediately after the four-month period following birth when they cannot legally be dismissed. After 24 months, nearly half of women who took maternity leave are out of the job market, and this pattern continues 47 months following maternity leave. The majority of departures from the job market are instigated by the employer, without cause. However, the effects are very heterogeneous and they depend on the mother’s education level: workers with more years of schooling had a 35% decline in employment 12 months after the start of maternity leave, while the decline was 51% among women with a lower level of education. Some companies have allowed their employees to extend their maternity leave for two months. For those who take six months of leave, there is a higher probability of remaining employed six months after the end of their leave (a difference of 7.5 percentage points), but this difference falls to zero 12 months after their leave. This was the first study on maternity leave to produce such a wealth of information on the trajectory of female workers in a developing country. It shows that the job market in Brazil differs from that in developed economies in terms of salary inequality, discrimination and informality. The study indicates that in Brazil, maternity leave of 120 days is not capable of keeping mothers in the job market. This shows that other policies (such as the expansion of nurseries and preschools) could be more effective to achieve this objective, especially to protect women with lower levels of education. The study shows policymakers that the extension of maternity leave in Brazil, to six months, has protected workers who become mothers, at least for some time after their return to work.