Cigarette smoking during pregnancy is one of the most preventable causes of infant morbidity and mortality, yet 80 % of women who smoked prior to pregnancy continue to smoke during pregnancy. Past studies have found that lower maternal-fetal attachment predicts smoking status in pregnancy, yet past research has not examined whether maternal-fetal attachment predicts patterns or quantity of smoking among pregnant smokers. The aim of this study was to examine the relationship between maternal-fetal attachment and patterns of maternal smoking among pregnant smokers. We used self-reported and biochemical markers of cigarette smoking in order to better understand how maternal-fetal attachment relates to the degree of fetal exposure to nicotine. Fifty-eight pregnant smokers participated in the current study. Women completed the Maternal-Fetal Attachment Scale, reported weekly smoking behaviors throughout pregnancy using the Timeline Follow Back interview, and provided a saliva sample at 30 and 35 weeks gestation and 1 day postpartum to measure salivary cotinine concentrations. Lower maternal-fetal attachment scores were associated with higher salivary cotinine at 30 weeks gestation and 1 day postpartum. As well, women who reported lower fetal attachment reported smoking a greater maximum number of cigarettes per day, on average, over pregnancy. Lower maternal-fetal attachment is associated with greater smoking in pregnancy. Future research might explore whether successful smoking cessation programs improve maternal assessments of attachment to their infants.