In France, as in the rest of Europe, family trajectories have become increasingly diversified. How does childbearing fit into these more complex conjugal patterns? More specifically, what is the impact of repartnering on men’s and women’s fertility? This article attempts to answer these questions, drawing on data yielded by the French version of the Generations and Gender Survey (Étude des relations familiales et intergénérationnelles, ERFI, INED-INSEE), conducted in 2005. Although births in reconstituted families have been extensively studied in Europe, scant attention has been paid to differences in the constraints encountered by men and women when they form a second union. We found that the woman’s age at repartnering accounts for the difference in the crude ratios of previously childless men to fathers, and previously childless women to mothers, who have a child in their second union. After controlling for woman’s age, we also noted that a couple is least likely to have a child after repartnering if both partners are already parents. If only one of them is a parent, the probability of having a child does not differ significantly from that of a childless couple.