Pain and Pregnancy, Part Three

The FDA has clearly established guidelines for safe usage of medications during pregnancy.
Generally speaking, there are five categories of drugs: 

Pregnancy category A

Adequate research has been done with the conclusion that drugs in this category are not likely to cause any harm to the fetus in the first trimester as well as later in pregnancy.

Pregnancy Category B

Studies carried out on animals have shown no adverse effects on the fetus; however, there is a lack of controlled studies on human pregnancy.

Pregnancy category C

Animal studies have shown evidence of harmful effects on the fetus; however, no controlled study has been done on a human pregnancy. The medicines may be prescribed in cases where the potential benefits outweigh the possible adverse effects.

Pregnancy category D

Studies done on human pregnancy have shown positive risks to the fetus. However, doctors might prescribe them in certain cases where the potential benefits outweigh the risks.

Pregnancy category X

Both human and animal studies have shown positive risks to the fetus, with the adverse effects extending to serious birth defects, miscarriage and fetal death. The possible risks of using these medicines outweigh any potential benefits.

The ONLY drug the FDA has deemed possibly safe for pain management in pregnant women is Tylenol/acetaminophen.  But, as previously mentioned in this blog, there is risk of hyperactivity/ADHD in children born to women who have used this drug during pregnancy.

Other drugs commonly used for pain management include 4 basic categories:

NSAIDs--These include aspirin, ibuprofen and some other commonly used pain relievers. Some are available over the counter.  They are rated in category B or D depending on which trimester they are used. They have been associated with increased risk of perinatal mortality, teratogenicity, and other fetal abnormalities. For more information, you can read in detail here.

Antidepressants --SSRIs are pregnancy category C.  There is risk of birth defects in a developing fetus, but each agent has its own specific issues.

Opioids--are also classified as pregnancy category C. The main reason for this is the risk of addiction in a developing fetus. Sometimes they are used on a risk/benefit basis, but it is not generally done. The British Medical Journal published an article about this in 2016.

Anticonvulsants are another class of agents that are used in pain management, usually for neuropathic pain. Pregabalin is one example of these drugs, it is classified as pregnancy category C due to the risk of fetal birth defects. Another drug in this category is gabapentin; it is also category C due to the risk of fetal toxicity. These drugs should only be used when the benefits outweigh the risks; contraception is advised if used in women of childbearing age.

The best advice here is to avoid ALL medications if possible during pregnancy. If you are a women of childbearing age, it is best to take precautions against pregnancy when using medications of any kind.  Take the time to know the risks and benefits of medications before using them for your sake, and your child's sake too!

Sources: Pregmed.org; BMJ.com; AAFP; Drugs.com