In the current study, we used 5 waves of longitudinal data from a large representative sample of Norwegian mothers (N = 84,711) to examine the association between romantic relationship satisfaction and self-esteem before and after childbirth in subgroups of first-, second-, third-, and fourth-time mothers. Maternal self-esteem showed a highly similar change pattern across subgroups. Specifically, self-esteem decreased during pregnancy, increased until the child was 6 months old, and then gradually decreased over the following years. The replication of this trajectory across subgroups and pregnancies suggests that this is a normative change pattern. For relationship satisfaction, the birth of the first child seemed to have the strongest impact compared with the birth of subsequent children. In first-time mothers, relationship satisfaction was high during pregnancy, sharply decreased around childbirth, and then gradually decreased in the following years. In second-, third-, and fourth-time mothers, the decrease in relationship satisfaction after childbirth was more gradual and linear compared with the sharp decrease found in first-time mothers. Moderate positive correlated changes between self-esteem and relationship satisfaction indicated that these constructs were linked over time. Discussion focuses on the implications of the results for theory and future research on self-esteem, relationship satisfaction, and personality–relationship transactions.