Pregnant and parenting young women rarely access community-based smoking cessation interventions. Targeted cessation interventions have been laden with challenges and have produced suboptimal outcomes. There is a paucity of qualitative research specific to young women that explores the context of their tobacco use, as well as their attitudes towards and experiences with smoking cessation supports in pregnancy and postpartum. To bridge this gap, an interpretive descriptive design was used to explore the personal and contextual factors influencing young women’s smoking behaviour during and after pregnancy. Factors were identified by analyzing influences at the multiple levels of McLeroy’s social ecological model of health promotion. Data were collected via in-depth, semi-structured interviews with young women aged 16-24 years (n=13) who smoked regularly preconception and were pregnant or parenting. Transcripts were analyzed using qualitative content analysis. Findings highlighted the complexity and chronicity of issues young women faced and emphasized the interplay of social determinants that influenced their smoking. Smoking was a crutch that helped them to relieve psychological distress stemming from exposure to adverse or traumatic experiences; and persistent stress in the context of socioeconomic hardship, neighborhood disadvantage and limited social support. Smoking also was influenced by young women’s understanding of the harms related to smoking during pregnancy and their reconceptualization of risk for smoking-related consequences postpartum. Young women described having limited discussions regarding smoking with maternity care providers and found their passive approach to cessation counselling unhelpful. They desired more comprehensive cessation support from providers. They expressed interest in a tailored group cessation program and offered suggestions for improving cessation supports for young women in pregnancy and postpartum. Study findings bridge gaps in the literature and identify appropriate next steps in addressing the issue of smoking in pregnancy and postpartum amongst young women by suggesting a multi-level approach to cessation. / Thesis / Master of Science (MSc)