Although the placental membrane is relatively thick and somewhat resistant to medication transfer during the first trimester, many major teratogenic effects
still occur as a result of medication exposure during this critical organ formation period.
Postcoital antifertility agents and their teratogenic effects
Three developmental periods--preconception, preimplantation, and gastrulation--appear to be particularly sensitive to the teratogenic effects
of alcohol, and it has been suggested that the clinical variability of FASD may be related not only to the dose of alcohol but also to when alcohol exposure occurs in relation to these developmental periods (Haycock 2009; Haycock and Ramsay 2009).
While alcohol has been shown to inhibit cyclins and CDKs, the actual changes in genetic expression that lead to the teratogenic effects
of alcohol are not yet known (Goodlett 2005).
Two large-scale studies of the possible teratogenic effects
of selective serotonin reuptake inhibitors have concluded that the absolute risk of birth defects related to the drugs is small.
As CellCept has been shown to have teratogenic effects
in animals at subclinical doses on a body surface area basis, it may cause fetal harm when administered to a pregnant woman.
of cholinergic insecticides in chick embryos IV.
Because of the emphasis placed on the teratogenic effects
and the potential link to depression and increased suicidal ideation with use of isotretinoin, other side effects may go unnoticed.
1968) and teratogenic effects
(Abramovici and Rachmuth-Roizman, 1983).
Although experiments with animals have provided considerable information regarding the teratogenic effects
of drugs, it is not always possible to extrapolate experimental findings from animals to humans.
Valproate may produce teratogenic effects
in the offspring of women receiving the drug during pregnancy.
Ribavirin causes significant teratogenic effects
and must not be used in women who are pregnant or breast-feeding and in men whose female partners are pregnant.