This dissertation tries to shed new light on the relationship between migration and fertility by concentrating on two migration contexts and applying different quantitative methods and taking various perspectives. The thesis consists of three independent research papers that are all tied together by the same theoretical framework that has been proposed in the literature to explain the link between migration and fertility (selection, disruption, interrelation of events, socialization and adaptation). Chapter 2 and 3 analyse the fertility behaviour of Senegalese migrants in Europe. While Chapter 2 takes a descriptive approach to family trajectories of male and female migrants and how they evolve in the immediate time before and after the migration move, Chapter 3 compares the fertility behaviour of migrant and non-migrant couples. Finally, Chapter 4 focuses on Latin American child migrants in Spain and their fertility preferences compared to native Spanish youth. The findings contribute to our understanding of the interplay between migration and fertility (preferences) and provide theoretical and methodological implications for the study of migrant fertility.