Background Incarceration is simultaneously a public health opportunity and a public health concern. We examined the association between maternal/partner incarceration in the year prior to birth and perinatal smoking.

Methods We pooled 2006–2010 data from the Centers for Disease Control and Prevention's Pregnancy Risk Assessment and Monitoring System. Controlling for age, race/ethnicity, education, marital status and other stressors, we assessed prevalence and heaviness of perinatal smoking.

Findings Women who reported incarceration of themselves or their partners in the year prior to delivery were more likely to smoke during the last trimester of pregnancy (adjusted OR (AOR) 1.51 (95% CI 1.36 to 1.67)), and they were more likely to smoke more than 10 cigarettes a day compared to smokers who did not report incarceration (AOR 1.35 (95% CI 1.10 to 1.65)). Patterns were similar for the 3 months prior to pregnancy and postbirth smoking.

Conclusions Incarceration of a parent in the 12 months before birth is associated with increased risk of fetal and newborn exposure to smoking. The criminal justice system can be utilised by public health practitioners to target perinatal smoking reduction interventions.