Increasing mothers' labor supply is a key policy challenge in many OECD countries. Germany recently introduced a generous parental benefit that allows for strong consumption smoothing after childbirth and, by taking into account opportunity costs of childbearing, incentivizes working women to become mothers and return to the labor force rapidly. Using a sharp regression discontinuity design, we estimate policy impacts for up to 5 years after childbirth and find significant and striking patterns. First, medium-run effects on mothers' employment probability are positive, significant and large, for some subgroups ranging up to 10 per cent. The effects are driven by gains in part-time but not full-time employment. We also find significant increases in working hours. Second, the probability of job continuity rises significantly, i.e. mothers return to their pre-childbirth employer at higher rates. Third, employers reward this return to work by raising job quality significantly and substantially. We argue that the policy generated a profound change in social norms: the new parental benefit defines an "anchor", i.e. a societally preferred point in time at which mothers return to work after childbirth.