Trajectories of return to cigarette smoking up to one year postpartum among people who quit smoking during pregnancy.

Relapse to smoking during the year after childbirth is common, but the time course of relapse after delivery is poorly understood. This study provides evidence for 4 distinct trajectories of relapse, and highlights variables linked to early relapse that may improve efforts to target and time intervention efforts. Specifically, assessing age at initiation, quantity of tobacco use prior to quit attempt, and number of previous quit attempts will identify pregnant people at greatest risk of early relapse. These findings also suggest that additional support early in the postpartum period is crucial for most people in the postpartum who will relapse.