Whether taking drugs during pregnancy has an effect on the fetus requires specific analysis of the problem. According to the U.S. Food and Drug Administration, that is, the FDA, after fetal teratogenicity tests based on animal tests and clinical, drugs are classified into five categories A, B, C, D and X, as follows: 1. Category A: drugs used in the early third month of pregnancy were not found to have an effect on the fetus, and no abnormalities were found during or after pregnancy; 2. Category B: animal tests did not show an effect on the fetus, but there was a lack of clinical control observation Class C: some drugs that have been confirmed in animal studies to have certain side effects on the fetus; Class D: positive evidence of risk to the human fetus; Class X: studies have confirmed that they can cause fetal abnormalities and human experience has shown that they can cause harm to the fetus. Therefore, the use of medication during pregnancy requires a specific judgment by a professional doctor for the condition of the pregnant woman.