Perinatal Exposure to Tobacco Smoke and Its Association with the Maternal and Offspring Microbiome: A Systematic Review

Background: The human microbiome, comprising trillions of microorganisms, significantly influences human health and disease. During critical periods like the perinatal phase, the microbiome undergoes significant changes, impacting lifelong health. Tobacco smoke, a known environmental pollutant, has adverse effects on health, particularly during pregnancy. Despite this, its association with the perinatal microbiome remains understudied. Methods: We conducted a systematic review to integrate findings on perinatal tobacco smoke exposure and its association with the maternal and neonatal microbiomes. We conducted a comprehensive literature search in the PubMed, Scopus, and Web of Science databases from January 2000 to February 2024. We selected studies that met predefined inclusion criteria and performed data extraction. Results: The review included eight studies that revealed diverse associations of perinatal tobacco exposure with the maternal and neonatal microbiome. Active smoking during pregnancy was linked to alterations in microbiome composition and diversity in children. Maternal smoking correlated with increased Firmicutes abundance and decreased Akkermansia muciniphila abundance in offspring. Additionally, exposure to thirdhand smoke in neonatal intensive care units was related to infant microbiome diversity. Infants exposed to tobacco smoke showed various microbial changes, suggesting potential implications for childhood health outcomes, including obesity risk. Conclusions: Perinatal exposure to tobacco smoke exerts significant influence on the maternal and neonatal microbiomes, with potential implications for long-term health outcomes. Addressing socioeconomic and psychological barriers to smoking cessation, implementing stricter smoking regulations, and promoting public health campaigns are essential steps towards reducing tobacco-related harm during the perinatal period. Further longitudinal studies and standardized assessment methods are needed to validate these findings and guide the development of effective preventive measures.