Potential pathways by which maternal second-hand smoke exposure during pregnancy causes full-term low birth weight

Abstract

It is well documented that maternal exposure to second-hand smoke (SHS) during pregnancy causes low birth weight (LBW), but its mechanism remains unknown. This study explored the potential pathways. We enrolled 195 pregnant women who delivered full-term LBW newborns, and 195 who delivered full-term normal birth weight newborns as the controls. After controlling for maternal age, education level, family income, pre-pregnant body mass index, newborn gender and gestational age, logistic regression analysis revealed that LBW was significantly and positively associated with maternal exposure to SHS during pregnancy, lower placental weight, TNF-α and IL-1β, and that SHS exposure was significantly associated with lower placental weight, TNF-α and IL-1β. Structural equation modelling identified two plausible pathways by which maternal exposure to SHS during pregnancy might cause LBW. First, SHS exposure induced the elevation of TNF-α, which might directly increase the risk of LBW by transmission across the placenta. Second, SHS exposure first increased maternal secretion of IL-1β and TNF-α, which then triggered the secretion of VCAM-1; both TNF-α and VCAM-1 were significantly associated with lower placental weight, thus increasing the risk of LBW. In conclusion, maternal exposure to SHS during pregnancy may lead to LBW through the potential pathways of maternal inflammation and lower placental weight.

Research Review: The role of obstetric and neonatal complications in childhood attention deficit and hyperactivity disorder – a systematic review

“…Future studies will have to figure out what is the specific role of preterm birth versus inflammation during pregnancy in determining the LBW of ADHD‐risk patients. This question is necessary considering that increased inflammation during pregnancy is one of the determinants of LBW (Niu et al., ) and it is associated with mothers’ psychiatric conditions (Serati, Redaelli, Buoli & Altamura, ) including those (e.g. bipolar disorder) (Buoli et al., ) which are considered as a risk factor for ADHD in the offspring (Axelson et al., ).…”

Tocotrienols and Oxidative Stress in Oocytes and Developing Embryos

“…Nicotine addiction during pregnancy has been shown to decrease offspring birth weight [25,26]. Decreased birth weight in the offspring is one of the factors contributing towards infant death in the world.…”

“…Effects of nicotine from cigarette smoke are not only limited to active smokers but are evident in passive smokers too. Higher concentration of cotinine in fetal blood exceeding maternal blood concentrations by 15% suggests that nicotine in second-hand smoke concentrates in the foetus [26,27]. Nicotine-induced embryonic malformation includes open neural tube in the anterior brain regions [28,29], embryonic retardation and reduced rate of embryo cleavage [23,30].…”

Tocotrienol-Rich Fraction Modulate the Phosphoinositide 3-Kinases/Akt Signaling Pathway Genes and Prevent Oxidative Stress in Nicotine-Induced Pre-Implantation Embryos

“…Cigarette smoke, with its major content, consist of the alkaloid nicotine (Nic), contains pro-oxidants that may raise ROS. This has been reported to damage the membrane structure at the chromosomal [26] and ultrastructural levels [27].…”

“…Nic addiction during pregnancy has been reported to decrease offspring's birth weight leading to infant death in the world [26,28]. Effects of Nic from cigarette smoke are not only limited to active smokers but also are evident in passive smokers too.…”