A systematic review of behaviour change techniques within interventions to prevent return to smoking postpartum.

"Declaration of interests None declared."

"Funding This work was supported by the Medical Research Council (PHIND grant ref.: MR/P016944/1)."

"We included randomised controlled trials of interventions where at least one component was designed to maintain smoking abstinence, versus a less intensive intervention or usual care. Participants were generally healthy pregnant or postpartum women who were recent smoking quitters (or a mixed population of recent quitters and smokers at baseline). Trials had to report smoking status (self-report or biochemically validated) in the postpartum period (beyond delivery). Trials not published in English were excluded due to the detailed intervention information required. Our review was registered on the PROSPERO international prospective register of systematic reviews (CRD42018075677). Conclusions: Future interventions to prevent postpartum smoking relapse might include these six BCTs to maximise effectiveness. Tailored self-help approaches, with/without counselling, may be favourable modes of delivery of BCTs.: Registration: PROSPERO CRD42018075677."