Levothyroxine and Pregnancy
Extensive clinical studies on levothyroxine and pregnancy have shown that the medication is safe for use during pregnancy. In fact, if you are pregnant and have a thyroid problem, not taking levothyroxine can lead to serious problems, such as a miscarriage. Therefore, it is important to treat a thyroid problem during pregnancy with medications such as levothyroxine.
Levothyroxine sodium is a prescription thyroid medication. When used appropriately, this medication is very safe for use during pregnancy. In fact, not taking levothyroxine during pregnancy (if you need to take it) can be quite dangerous.
Levothyroxine and Pregnancy Category A
The U.S. Food and Drug Administration (FDA) uses a category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category A is given to medicines that have been extensively studied in pregnant humans and do not appear to cause any harm to the fetus.
Very few medications have been given this classification; it is an excellent indication that a medication is safe for use during pregnancy. You can feel confident that levothyroxine is one of the safest medications for use in pregnancy (when used appropriately).
Because hypothyroidism can cause serious problems (such as miscarriages), it is important to treat an underactive thyroid during pregnancy. This is why most healthcare providers check your thyroid (using blood tests) early in pregnancy, even if you have never had thyroid problems.
If you are already taking levothyroxine, it is likely that your dose may need to be increased throughout your pregnancy. In fact, your dose may need to be increased as early as four weeks into your pregnancy. Your healthcare provider should monitor you closely and adjust your levothyroxine dosage as necessary.