Final answer:
ACE inhibitors are contraindicated during pregnancy as they can cause severe fetal malformations including renal failure and limb deformities. Teratogens, such as thalidomide, have historically caused severe limb defects, and exposure to certain chemicals and environmental factors can also lead to developmental issues in fetuses.
Step-by-step explanation:
Angiotensin-converting enzyme (ACE) inhibitors are a class of medications primarily used to treat high blood pressure and heart failure. They are generally considered contraindicated during pregnancy, especially in the second and third trimesters, due to the risk of causing fetal renal failure and oligohydramnios. These complications can lead to further severe fetal abnormalities such as pulmonary hypoplasia and limb contracture, as well as cranial bone deformities.
Teratogens, including certain prescription drugs beyond ACE inhibitors, pose a significant risk for embryogenesis and fetal development. These substances can have devastating effects on a developing fetus, similar to historical examples such as thalidomide, which led to limb defects when it was used by pregnant women to combat morning sickness before its teratogenicity was known.
Aside from pharmaceuticals, other environmental factors and substances, like smoking and chemical compounds such as methyl iodide and bisphenol A, have suspected teratogenic effects. These agents can lead to various defects and developmental issues, highlighting the critical importance of careful substance use and exposure management during pregnancy.