Because you are planning to conceive in a few months, your health and each exposure to your system become very important. You should schedule a prenatal visit with your primary care doctor
so that you may discuss your pre-pregnancy health. If this is your first pregnancy, your doctor will need to review your medical problems, send appropriate screening labs, and ensure that you receive any vaccinations that need to be administered in the months prior to conception. In addition, it is important to take a prenatal supplement which contains folic acid, iron and calcium.
For the majority of medications, there is limited research in safety during and immediately preceding pregnancy. Kenalog is a class of steroid. Injections deliver the medication throughout your system. It is unclear how long this will stay in your system, however you may want to visit with your doctor or allergist to discuss this further. Kenalog is a class C medication, therefore has demonstrated harm to the fetus in animal studies, including serious effects such as decreased fetal growth and birth weight, oral clefts when used in the first trimester. Unfortunately, there are no human studies of kenalog use in pregnancy. Kenalog is also transmitted to breast milk.
While you are planning to receive kenalog prior to conception, pregnancy is unpredictable and may occur before planned. If you allergies are very bothersome, you will need to discuss the risk and benefit of zyrtec during pregnancy with you obstetrician. While there is no documented harm to fetus in animals, it is not studied in humans. Again, please with your primary care doctor.