There is no effect of taking progesterone when pregnant, it is generally used to protect the fetus, and sometimes progesterone is taken to regulate menstruation, but in the case that you do not know you are pregnant, if you take progesterone, it is also good for pregnancy, because progesterone itself has the effect of protecting the fetus, so there is no need to worry about taking progesterone when pregnant, because this drug has been proven through a large amount of information that it has no effect on the fetus. However, people who take progesterone sometimes experience side effects such as dizziness and nausea. Once pregnancy is confirmed, the drug should be discontinued, and if you need to preserve the fetus, you can switch to progesterone with intramuscular injections, which do not have such side effects. Originally, early pregnancy reactions such as dizziness and nausea may occur after pregnancy, and if these symptoms occur again when taking progesterone, it will aggravate the symptoms of early pregnancy reactions and affect the health of the pregnant woman.