Nasonex and Pregnancy
In animal studies involving mometasone (the active ingredient in Nasonex) and pregnancy, the drug increased the risk of birth defects, low fetal weight, and slow bone development. As a result, the FDA has classified Nasonex as a pregnancy Category C medication. If you are taking Nasonex and pregnancy occurs, your healthcare provider may have you continue taking the drug if the benefits outweigh the risks.
Taking Nasonex During Pregnancy: An Overview
Nasonex® (mometasone nasal spray) is a prescription medication approved to treat nasal polyps and nasal allergies. Nasonex is part of a group of medications known as corticosteroids. Animal studies have shown that taking mometasone (the active ingredient in Nasonex) can increase the risk of birth defects.
Nasonex and Pregnancy Category CThe U.S. Food and Drug Administration (FDA) uses a pregnancy category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category C is given to medicines that have not been studied in pregnant humans, but do appear to cause harm to the fetus in animal studies. Also, medicines that have not been studied in any pregnant women or animals are automatically given a pregnancy Category C rating.
When given to pregnant mice, rats, and rabbits, mometasone increased the risk of birth defects, low fetal weight, and slow bone development. In these studies, mometasone was given as an injection just under the skin. It is not known if Nasonex (which is sprayed into the nose, not injected) will also cause similar problems.
However, it is important to note that animals do not always respond to medicines in the same way that humans do. Therefore, a pregnancy Category C medicine may be given to a pregnant woman if the healthcare provider believes that the benefits to the pregnant woman outweigh any possible risks to the unborn child.