Perinatal smoking is associated with a wide range of negative reproductive and pregnancy outcomes. The aim of the current study was to examine the prevalence and characteristics of women who report smoking prenatally and quit during pregnancy in a large sample of Romanian women. Understanding which women are more likely to quit will contribute to public health knowledge that will help more women stop smoking prior to or during pregnancy and prevent relapse postpartum. This cross-sectional analysis was conducted based on cross-sectional data collected between May 2012 and April 2015 as part of a cohort study of pregnancy implemented in six clinical settings in central Romania (N = 2370). Approximately 28 % of the sample reported smoking in the 6 months prior to learning they were pregnant. Half of the women who reported smoking 6 months before learning of their pregnancy, also reported that they stopped smoking by the time of the interview. Overall, tobacco consumption decreased from a sample mode of 10 cigarettes/day (range: 1-30) before pregnancy, to a sample mode of 5 cigarettes/day (range: 1-25) at the time of the interview. Women who quit had a higher socioeconomic position, were more likely to live in urban areas, partnered, primigravid, nulliparous, and reported lower anxiety and more social support. The combination of a socioeconomic gradient, less anxiety, and more social support suggests that efforts should be increased to target lower income, less educated, multigravid, and multiparous women and to develop programs that heighten social support and alleviate anxiety.