Effect of prenatal passive tobacco smoke exposure on full-term birth weight of born neonates:SR

Prenatal smoking increases the risks of pre-term birth, stillbirth, neonatal death, and perinatal death as well as neurodevelopmental disorders in children. However, there is a lack of consistency in research published about association/impacts of passive smoking and low birth weight (LBW). Hence, we carried out this systematic review to determine whether or not there is a relation between prenatal tobacco smoke exposure and full-term LBW infants. Following PRISMA guidelines, we carried out systematic searches with PubMed, CINAHL, PsycInfo, and Embase for cohort case-control studies the 31-year period from 1991 - 2022. Of the 2,877 articles identified, 835 duplicates were removed. Title screening was done for 2,126 articles. 25 articles met the inclusion criteria that were Peer reviewed full-text articles in the English language and related to LBW due to passive smoking only. We found 20/25 articles showed a significant relationship with an OR ranging between 2.14 and 54.9 respectively between exposure to environmental tobacco smoke (ETS) and LBW infants at term and 5 articles showed no association with an OR ranging between 0.48 and 1.51. A significant difference found between the sample size among the studies included influencing the outcome of the study (ranging from smallest (n = 208) and largest (n = 17412). Mean age of mother was 29.6±3.8 and mean birth weight was 3,212±467.1. Nicotine level > 4.1 ng/mL or duration of exposure 24.4 hours/week gives strong evidence of prevalence of LBW among SHS exposed mothers. Compiled evidence suggests that, there is a significant association between prenatal passive smoke exposure and neonatal birth-weight at full term. There is a need for health researchers and public health experts to design and implement targeted programmes to reduce LBW due to passive smoke in our societies. KEY MESSAGES: • Exposure to ETS from domestic sources has a substantial influence on birth weight. • Combining educational programmes and legislative interventions is required to eliminate infants’ contact with tobacco smoke in utero and throughout childhood.