Fetal heart failure is associated with congenital heart disease, inflammation of the fetal lungs due to bacterial or viral infections, and the presence of arterial ductus arteriosus in the fetus. 1. Congenital heart disease: it is a kind of cardiovascular malformation caused by abnormal development of fetal cardiovascular in early pregnancy. It is characterized by symptoms such as dyspnea, cyanosis, and reduced activity endurance and even heart failure. Chromosomal aberrations, genetic defects, environmental factors may lead to fetal congenital heart disease. 2. Pneumonia: mostly caused by bacterial or viral infections leading to inflammation of the fetal lungs, most of which are characterized by fever, cough, dyspnea and shortness of breath, which in turn can lead to heart failure. 3. Arterial ductus arteriosus: viral infection in early pregnancy may lead to arterial ductus arteriosus in the fetus. This may lead to fast breathing, shortness of breath and even heart failure. Clinical advice to pregnant women to carry out regular pregnancy checkups, when abnormalities occur, improve the examination to clarify the cause of the disease, and then give targeted treatment or treatment.