Environmental teratogens

Drugs
Identification of drugs that cause fetal malformations is
important as they constitute a potentially preventable cause of
abnormality. Although fairly few drugs are proved teratogens in
humans, and some drugs are known to be safe, the accepted
policy is to avoid all drugs if possible during pregnancy.
Thalidomide has been the most dramatic teratogen identified,
and an estimated 10 000 babies worldwide were damaged by
this drug in the early 1960s before its withdrawal.