This study of the experiences of recent Mexican immigrants living in California explores the changing perceptions of sexual and societal norms, including gender roles and resulting reproductive decision-making, that appear to accompany the migration process. These norms are compared to those held by migrants' families of origin in Mexico. We analysed 44 semi-structured interviews conducted with a client-based population in order to identify reproductive perceptions and practices that appear to be influenced by recent migration. Using a grounded theory approach, 26 women and 18 men's narratives were analysed to understand the complexity of changing expectations and resulting reproductive health practises. The social marginalisation and isolation of immigrants' experiences, the challenges of new socio-economic factors and access to health services appear to reshape views on reproductive decisions. While traditional gender roles and large families remain a spoken ideal, in practice these reproductive patterns are changing. Our analysis suggests that the migration process does alter relationships, reproductive decisions and contraceptive use among recent Mexican immigrants. The public health goal should be to provide an array of accessible and affordable services, tailored to the needs of this increasingly larger population of recent Mexican migrants in California and throughout the USA.