Background: Perinatal problems can occur in fetuses who have been exposed to alcohol or tobacco. The relationship between alcohol and tobacco use and the motor and cognitive development of infants, whether used separately or concurrently, is currently poorly understood. Objective: The goal of this study is to determine whether maternal use of tobacco or alcohol during pregnancy affects the motor and cognitive development of the fetus. Methods: 316 mothers and children from a cohort who were first assessed during the prenatal period (22–25 weeks of pregnancy), then again after birth, were included in the study. According to the alcohol and/or tobacco use indicated by the mothers at delivery, the children were split into four groups: those who had neither used alcohol nor tobacco (NC), those who had each used it separately (AC), those who had both used them simultaneously (ACTC). Mother's postpartum depression, gestational age, and intrauterine development limitation were all assessed. The third edition of the Bayley Scale of Infant and Toddler Development screening instrument was used to evaluate the children's motor and cognitive development. Results: Less mothers without partners, mothers under the age of 20, and mothers over the age of 35 took part in the follow-up in greater numbers. The moms in the ACTC group had lower gestational ages, higher rates of intrauterine growth restriction, and more postpartum depression cases. The only group that demonstrated an increased risk of motor delay, notably for fine motor skills, when compared to the NC group was the ACTC group; separate alcohol or cigarette usage did not. Conclusion: Smoking cigarettes and drinking while pregnant had a negative impact on the health of the mother, the unborn child, and the mother's life. The negative effects of these substances and the child's long-term growth were increased by concurrent alcohol and cigarette usage.