Q: Are some antibiotics safer than others during pregnancy and which ones are safe according to the category?

A: Yes, some antibiotics are considered safer during pregnancy than others. In order to simplify the huge list of antibiotics, there are five categories of antibiotics - Categories A, B, C, D and X. The doctor will choose the best antibiotic based upon the infection being treated and the safety of the antibiotic needed to clear the infection.

These categories are not only used for antibiotics. All medications can be categorized into either A, B, C, D or X. Most of the time, the obstetrician will try to recommend medications that fall into categories A, B, or C.

In some cases, the antibiotic needed to treat the infection will fall into a category that is considered unsafe for use during pregnancy, like D or X. If this is the case, the obstetrician will need to weigh the benefits with the risks associated with using that antibiotic, though X should never be given. If the benefits outweigh the risks, the antibiotic will be prescribed to the pregnant woman as long as she agrees to the treatment. If she does not agree, another treatment method will be chosen, if available, but there could be added risk to the fetus if the infection is not cleared.

Just because an antibiotic falls into a less safe category does not mean fetal harm will occur in every case. In most cases, there will be no negative effects on the fetus. The categories can be used as a guideline for obstetricians not as a definitive ruling.
Using antibiotics that are not prescribed to the pregnant woman is not acceptable. Just because a family member or friend has been diagnosed with the same infection does not mean the same medication will be prescribed. This can cause undue harm to the fetus.