Teratogenesis

Teratogenesis is a process that causes birth defects or malformations in an embryo or foetus. Teratology is the study of the causes and underlying mechanisms leading to birth defects or malformations. These may include disorders without any obvious structural malformations, such as intellectual disabilities. A teratogen is a substance (from outside the body) that causes birth defects or malformations. Examples of teratogens include medicinal drugs, such as thalidomide; environmental toxins, for example cadmium as well as environmental pollutants, including pesticides and endocrine-disrupting compounds. Other causes of teratogenesis include viruses, for example rubella and Zika virus; physical compression in utero and poor diet. Animal models are used to study the mechanisms by which teratogens result in birth defects or malformations, and these studies can also give insights into normal development. The study and understanding of teratogenesis is also essential for making safer and more targeted therapeutic drugs.