Covid-19 vaccines were started developing with testing on humans in March 2020. The FDA says that these Covid-19 vaccines are safe to take. But still, it is not clear that they are safe for pregnant women. It has been stated that two people in the U.K. after taking the Pfizer vaccine had worse allergic reactions. So, for now, people avoid taking this vaccine. People aged 18 and older can take vaccines developed by Moderna.