Many women, during the course of their pregnancy, take different kinds of medication, however some medications are dangerous to take in pregnancy. Extreme precaution should be exercised regarding use of any sort of drugs during pregnancy and they should be taken only if prescribed or directed by your healthcare provider.
Some birth defects are associated due to the drugs taken during pregnancy. The drugs that are absolutely contraindicated for pregnancy and carry the risk of turning a pregnancy into high-risk ones have been categorized as category D drugs by the FDA (Food and Drug Authority) as they can cross the placenta and have potentially dangerous effects on the fetus. Some of the drugs that are absolutely contraindicated during pregnancy include and are categorized as an X.
When a medication cause a birth defect it is often known as a treratogen meaning: Teras-”MONSTER” Genic-”PRODUCING”. A birth defects is something that is categorized as having a defect or distortion of the anatomy. These can range from a cleft lip, cleft palate, clubfoot, neural tube defects, missing or malformed limbs/fingers. They can also include some behavorioral or biochechmical abnormalities.
Medications absolutely contraindicated in Pregnancy
- Thalidomide: thalidomide is a known teratogen that if consumed during pregnancy, can pose risk of fatal birth defects like bone hypoplastcity, congenital bone absence, micropinna, reduced or absent external auditory meatus, phocomelia, Amelia, facial nerve palsy, anopthalamos (absence of eyes) or micropthalamos (small sized eyes) and cardiac defects.
- Warfarin: warfarin is an anti-coagulant normally prescribed in case of diseases like blood clots, DVT or pulmonary thromboembolism etc. When given during pregnancy, it can result in CNS defects, spontaneous abortion. Still births, post-partum hemorrhage and ocular abnormalities. It is categorized as a category X drug.
- Isotretinoin: Isotretinoin is indicated for various skin disorders such as acne. It is however, a category X drug during pregnancy as research has revealed a teratogenic nature of the drug. Its use during pregnancy can lead to facial, ocular, otologic and skull abnormalities. It has also been shown to cause CNS and cardiac defects along with hormonal abnormalities. Cases of low IQ after isotretinoin use have also been reported.
- Phenytoin: Also known as Dilantin, phenytoin use during pregnancy can result in fetal hydantoin syndrome which is characterized by cranial, facial and limb defects. Cleft lip or palate and abnormal size of head are common in children suffering from it. Distal phalangeal hypoplasia, reduced size or absence of nails, abnormal palmar crease are the limb defects noted in such children. Low IQ level has also been attributed to phenytoin use during pregnancy.
- Lithium: Lithium use during pregnancy has been related to bipolar disorder in the new born. It can also lead to congenital cardiac defects particularly Ebstein’s anomaly, cyanosis in newborns, Hypotonia, atrial flutter and bradycardia. This is why it is absolutely contraindicated for pregnancy and has been categorized as a category D drug. Lithium can also cause these effects in breastfed children so should be avoided by the nursing mothers. It should only be given during pregnancy if its potential benefits outweigh the risks.