BackgroundAmong the strategies to encourage pregnant women to be vaccinated against pertussis in the postpartum period, that of giving them a prescription has been evaluated only sparsely.ObjectiveTo measure the effect of giving women who are not immunized against pertussis a prescription for the vaccine at discharge from the maternity unit.Material and methodsSingle-center before-and-after study (2011: before; 2015: after). All women received both oral and written information about vaccination against pertussis. During the after period, they were also specifically asked their immunization status during pregnancy. Those currently unimmunized received a written prescription for it at discharge.ResultsAmong the women unimmunized at delivery, the percentage who were vaccinated postpartum climbed from 17 to 42% between 2011 and 2015 (p < 0.001), while the percentage of their unimmunized partners who were vaccinated remained stable (27 and 29%, p = 0.74). During this time, the percentage of women immunized against pertussis at the beginning of pregnancy rose from 32 to 52% (p < 0.001). Finally, the percentage of all women protected against this disease postpartum climbed from 44 to 72% between these two periods (p < 0.001).ConclusionsIn the postpartum period, giving a prescription for pertussis vaccine to women unimmunized is accompanied by a significant elevation in their vaccination rate. Nevertheless, this rate remains low and better strategies have to be implemented.