In the context of the trend toward delayed parenthood, this study examines whether older maternal age is associated with greater psychological maturity and whether greater psychological maturity provides any adaptive benefit during the transition to motherhood. A sample of 240 predominantly English-speaking Australian women in a metropolitan area expecting their 1st baby (mean age = 32.81 years; 41% conceived after fertility treatment) completed measures of psychological maturity (hardiness, ego development, and ego resiliency) and pregnancy adaptation (maternal fetal attachment and formation of a maternal identity) in the 3rd trimester of pregnancy and a measure of postnatal adjustment at 4-6 months postpartum. Structural equation modeling showed age was positively associated with a latent construct of psychological maturity, and psychological maturity was associated with more optimal adaptation in pregnancy and early motherhood. Both psychological maturity and pregnancy adaptation predicted positive postnatal adjustment. Age was indirectly related to adaptation through its relationship with psychological maturity. The relationships in the model applied regardless of mode of conception (fertility treatment or spontaneous). Potentially confounding contextual factors associated with older age at motherhood, higher education, and maternal and child health were included in the model. These results suggest that psychological maturity is a benefit of motherhood at older ages.