Does the age difference between partners influence the career achievements of women?

Women earn less than men at most career stages, and they also tend to partner with older men. This study investigates whether being the younger partner in a marriage reduces a woman’s incentive to pursue an independent career. We hypothesize that the income gender gap might be partially explained by the age differences between spouses. Using both a within-twin (n = 4716) and pooled-twin (n = 13354) design to more readily account for differences in early household environments, we investigated for Denmark whether the age gap between a female twin and her partner has any influence on her income. The hypothesis could not be confirmed, as the age gap between partners did not appear to be associated with women’s earnings. The finding that women’s wages were generally unaffected by partnering with an older man could be a result of heterogeneous groups of women entering men-older partnerships. Future research should explore this question further by using the number of promotions to assess the career success of women, and should extend this work to countries with different social welfare systems and less egalitarian gender norms.