The paper investigates migrant–nonmigrant differentials over time among women in Germany after their first childbirth; we look at the transitions to paid work or to a second child. Our observation period covers almost 30 years, in which family policies changed substantially. Most notably, the year 2007 marked a shift in (West) Germany’s parental leave policy from a conservative family model to a policy directed toward fostering work and family reconciliation. Across these policy periods, we investigate whether population subgroups, i.e., first-generation migrants and migrant descendants, show different patterns in their transitions after the first childbirth compared to the non-migrant majority population. We use data of the German Socio-economic Panel Study (GSOEP). Our sample consists of 3555 mothers of one child, about 13% of whom are first-generation migrants and 16% are migrant descendants. We estimate event-history models: using competing risks analyses, we study transitions following the first birth, specifically, (re)entering work and having a second child. We find that the transition (back) to work increased significantly from one policy period to the next among non-migrants. Increases among migrants varied between the migrant generations, were smaller and occurred later. Hence, we find an increasing gap between first-generation migrants and non-migrants across policy periods, with migrant descendants in between. To some extent, the migrant–nonmigrant gap traces back to different compositional and institutional effects and varies across origin groups. By contrast, the transition rates to a second child decreased among non-migrants, but hardly varied across periods among migrants. Thus, our results demonstrate increasing differentials between societal groups in their work-family reconciliation behavior, to which the modern parental leave policies may have contributed. We discuss the implications of these results for researchers, society and policymakers.