What does teratogen mean?
A teratogen is a substance or other agent that can cause abnormal development in an embryo or fetus, particularly by producing structural malformations. The term is used most often in medicine, pharmacology, toxicology, and public-health discussions of pregnancy. Drugs are among the best-known possible teratogens, but teratogens can also include certain chemicals, radiation, and biological agents. Not every harmful substance is a teratogen: the defining feature is an ability to interfere with prenatal development. The related adjective “teratogenic” describes such an effect, as in “teratogenic risk,” while “teratogenicity” names the quality or degree of that capacity. Knowing whether a substance is teratogenic is important because the potential effects depend on factors such as dose, timing, and duration of exposure. Early pregnancy is a period of especially rapid development, making it a focus of medical guidance and research.
nounA drug, chemical, biological agent, or other substance that can cause abnormal development or structural malformations in an embryo or fetus.
- An agent capable of causing abnormal embryonic or fetal development, especially a substance that produces congenital malformations.
"The physician advised pregnant patients that the medication was a known teratogen."
"Exposure to a teratogen during the first trimester can disrupt fetal development."
"The researchers tested whether the environmental contaminant was a potent teratogen."
The plural is used when referring to multiple substances or agents that can cause developmental abnormalities.
"Several recognized teratogens are listed in the pregnancy safety guidance."
A teratogen is not simply anything toxic: what makes it a teratogen is its ability to disrupt development before birth.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of teratogen
“Teratogen” combines the Greek noun téras, meaning “monster” or “monstrosity,” with the combining form -gen, meaning “producer” or “agent.” The word belongs to a family of scientific terms that includes “teratology,” the study of congenital abnormalities, and “teratoma,” a tumor derived from multiple tissue types. Its underlying sense is therefore an agent that produces monstrous or abnormal development.
Related word forms
How teratogen is actually used
This is chiefly a medical, toxicological, and pharmacological term. It is used particularly in relation to pregnancy and prenatal exposure; the related adjective is “teratogenic.”
Easily confused with teratogen
A teratogen is an agent that can cause developmental malformations, whereas a teratoma is a tumor containing tissue resembling that from multiple types of body structures.