Teratogenesis
Teratogenesis is a medical term from the Greek, literally meaning monster making. It has gained a more specific usage for the development of abnormal cell masses during fetal growth, causing physical defects in the fetus.There are a large number of teratogenic materials, such as Diethylstilbestrol and Thalidomide. The Rubella (German measles) virus is also teratogenic, as is use of large amounts of alcohol during pregnancy (Fetal Alcohol Syndrome).
The term teratogenesis refers to the production of congenital malformations, such as cleft lip and/or palate, anencephaly, ventricular septal defect, medically serious abnormalities present at birth. The term derives from teratology, the study of the frequency, causation, and development of congenital malformations--misleadingly called birth defects.