Realistic or unrealistic expectations are formed prior to having the child and can affect the relationship quality of the mother and infant at 3 months and the reported maternal stress levels at 6 months. Violated expectations can either positively or negatively change the course of the relationship quality and stress levels. To test the nature of such relations, a series of regression analyses and one-way ANOVAs examined the associations between maternal expectations (and violations of maternal expectations) and maternal stress at 6 months. Further, mother-infant relationship quality was examined as a possible mediator of this association. Results indicated that prenatal maternal expectations and maternal expectations at 6 weeks were significantly correlated with maternal stress at 6 months. The higher the maternal expectations, the lower the maternal stress. There were no significant relations discovered between maternal expectations and relationship quality or relationship quality and maternal stress. Relationship quality does not mediate the relation of maternal expectations (or violated maternal expectations) and maternal stress. Violated maternal expectations that moved towards realistic did achieve better relationship quality scores, but maternal stress scores stayed consistent no matter the direction of the change.