Cigarette smoke contains a complex mixture of nicotine, cotinine, cyanide, thiocyanate, carbon monoxide, cadmium, lead, and various hydrocarbons (Stillerman, 2008). In addition to being fetotoxic, many of these substances have vasoactive efects or reduce oxygen levels. Tobacco is not considered a major teratogen, although selected birth defects have been reported to occur with greater frequency among newborns of women who smoke. It is plausible that the vasoactive properties of tobacco smoke could produce congenital defects related to vascular disturbances. For example, the prevalence of Poland sequence, which is caused by an interruption in the vascular supply to one side of the fetal chest and ipsilateral arm, is twofold greater in smokers (Martinez-Frias, 1999). A small increased risk for cardiac anomalies has also been reported and may be dose related (Alverson, 2011; Malik, 2008; Sullivan,
Teratology, Teratogens, and Fetotoxic Agents 249 2015). One study analyzing more than 6 million births found an association between maternal smoking and hydrocephaly, microcephaly, omphalocele, gastroschisis, cleft lip and palate, and hand abnormalities (Honein, 2001). Electronic nicotine delivery systems are not considered safe, as nicotine may have adverse efects on fetal brain and lung development (American College of 0bstetricians and Gynecologists, 2017 d).
he best-documented adverse reproductive outcome from smoking is a dose-response reduction in fetal growth. Newborns of mothers who smoke weigh on average 200 g less than newborns of nonsmokers (D'Souza, 1981). Smoking doubles the risk of low birthweight and raises the risk of fetal-growth restriction two-to threefold (Werler, 1997). Even secondhand smoke increases the risk for low birthweight (Hegaard, 2006). Women who stop smoking early in pregnancy may have neonates with normal birthweights (Cliver, 1995). Other adverse outcomes associated with cigarette smoking include preterm birth, placenta previa, placenta abruption, spontaneous abortion, and sudden infant death syndrome (American College of Obstetricians and Gynecologists, 2017d). Risks of childhood asthma and obesity are also increased.
Abel EL, Hannigan ]H: Maternal risk factors in fetal alcohol syndrome: provocative and permissive inluences. Neurotoxicol Teratolo17(4):445, 1995
Actelion Pharmaceuticals: Opsumit (Macitentan) prescribing information, 2017. Available at: http://www.opsumit.com/opsumit-prescribing-information. pd. Accessed September 24, 2017
Actelion Pharmaceuticals: T racleer (Bosentan) prescribing information, 2016.
Available at: www.tracleer.com/assets/PD Rs/T racleer_Full_Prescribin� Information. pdf. Accessed September 24, 2017
Adam MP, Polifka ]E, Friedman ]M: Evolving knowledge of the teratogenicity of medications in human pregnancy. Am] Med Genet C Semin Med Genet 157(3):175,o2011
Ailes EC, Gilboa SM, Gill SK, et al: Association between antibiotic use among pregnant women and urinary tract infections in the irst trimester and birth defects, National Birth Defects Prevention Study 1997 to 2011. Birth Defects Res A Clin Mol Teratol 106(1o1):940, 2016