Parenthood is a key life-course transition strongly impacting couples’ work-family arrangements. However, this transition has different implications for women and men, with mothers generally making more substantial changes to their participation in employment than fathers. This gendered effect of parenthood on career trajectories is a major reason for labour market inequalities between women and men over the life-course. In Switzerland, the prevailing gender culture and policies foster a gendered work-family arrangement for new parents. It is therefore particularly difficult for new parents to ‘undo’ gender, i.e., to have work-family arrangements that reduce rather than reproduce gender differences. This paper adopts a life-course and gender perspective and investigates the effect of couples’ attitudes towards gender equality on new parents’ paid work adjustment and arrangement. Regression analyses based on yearly data from 22 waves of the Swiss Household Panel (2000-2020) are used to examine variations in couples’ employment behaviours around family formation. The sample consists of cohabiting heterosexual couples who became parents during survey participation. By considering both partners’ attitudes jointly, we find that, compared to couples where both partners have traditional or weak egalitarian attitudes before the transition, couples where both partners have strong egalitarian gender attitudes are more likely to undo gender in their paid work adjustment and arrangement after parenthood.