The most dangerous period for pregnancy-related heart disease includes 32-34 weeks of gestation, labor and delivery, and the 3 days after delivery, which are the most dangerous times for pregnant women with pregnancy-related heart disease. 32-34 weeks is the time when the amount of blood returned to the heart is the highest, which increases the burden on the heart. The delivery period includes the end of the first stage of labor and the second stage of labor, when the patient has to hold her breath and exert herself, which is a very big test for the heart of the pregnant woman. The third day is the 3 days after delivery, which is another blow to the pregnant woman’s heart due to the increase in the amount of returning blood after the end of labor. These 3 periods are a great test for the pregnant woman’s heart, and only after these 3 periods are passed, the patient with pregnancy-related heart disease is safe. For these 3 high-risk periods, it is necessary to strengthen the management, and in any period, the management of patients with combined heart disease of pregnancy should not be relaxed, and the monitoring should be strengthened so that they can safely pass these 3 periods.