Describe common teratogens and their effects

Question

What will be an ideal response?

Answer 1

ANSWER:
?Any environmental agent that has the potential to harm the embryo is referred to as a teratogen. It may be a drug that the mother takes, such as cocaine or alcohol; a disease, such as German measles (rubella); or chemicals that the mother inhales, such as certain cleaning fluids. All these substances have the potential to cause birth defects. The critical factor seems to be when the mother is exposed to these agents. These sensitive periods emphasize the complex interplay of nature and nurture on development. Certain organs and systems are more vulnerable to the effects of teratogens during particular stages of prenatal development. Notice that the most severe effects are most likely to occur during the embryonic stage of development. Because a woman usually does not discover that she is pregnant until the embryo is already formed and developing, she may unknowingly expose her developing baby to harm.
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Women who use any type of drug during pregnancy can potentially affect their babies. Women who smoke during pregnancy reduce the flow of oxygen to the fetus; their babies tend to be irritable, have respiratory problems, and have lower birth weight (Lester, Andreozzi, & Appiah, 2004; Shea & Steiner, 2008). Women who drink alcohol heavily during pregnancy put their unborn children at risk for fetal alcohol syndrome (FAS). Children with FAS tend to have low birth weight, brain abnormalities, and lowered intellectual functioning, and tend to exhibit limb, head, and facial deformities (Dalen et al., 2009; Ikonomidou et al., 2000; Ornoy & Ergaz, 2010). Even moderate drinking can affect the embryo’s brain development, resulting in later intellectual impairments (Kraft, 1996; Rasmussen, Soleimani, & Pei, 2011). Prenatal alcohol exposure has also been linked to an increased risk of low birth weight and poorer visual acuity in infancy (R. C. Carter et al., 2005; Mariscal et al., 2006).
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Illegal drugs also produce damaging effects. If the mother is a heroin addict, the baby will be born addicted and have to undergo withdrawal. Crack or cocaine babies are often born premature, underweight, and irritable, and tend to have poor feeding habits (Frank et al., 2002; Gouin et al., 2011).
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Prenatal exposure to teratogens may also have long-term effects. Children exposed to drugs during pregnancy tend to be more impulsive, less adaptable, and evidence more behavioral problems later in life than children not exposed to drugs during pregnancy (Espy, Riese, & Francis, 1997; Richardson et al., 2011). In southern Japan, adults whose mothers took in high levels of methylmercury (found in fish) during pregnancy have shown accelerated rates of aging (Newland & Rasmussen, 2003). There is also increasing evidence that maternal stress and anxiety during pregnancy may influence the offspring’s development. High levels of maternal stress hormones during pregnancy increase the risk of preterm birth and are associated in childhood with higher blood pressure, behavioral and emotional problems, as well as a higher risk of obesity (Coussons-Read, 2012; Harris & Secjkl, 2011; Reynolds, 2013; Rinaudo & Wang, 2012).