If a pregnant woman is unable to catch her breath during late pregnancy, it is generally a normal physiological change during pregnancy if the degree is not serious. It may also be caused by environmental factors, anemia, increased heart burden or abnormal heart function and related diseases. 1. Environmental factors: If a pregnant woman is in a confined space for a long time, poor air circulation and a stuffy environment may cause her to lose her breath and even faint in severe cases. Generally, pregnant women can be effectively relieved after resting or strengthening air circulation; 2, anemia: if pregnant women have anemia, the number of red blood cells in the blood is reduced, the ability to carry oxygen will be reduced, and the symptoms of breathlessness may occur in daily life. At this time, you can moderately eat more blood and gas foods, such as animal liver, dates and other foods, and iron supplements to correct anemia; 3, increased burden on the heart: with the prolongation of pregnancy, the fetus increases, the size of the uterus is gradually increasing, upward pressure on the diaphragm, heart and lungs, while pregnant women need to bear the burden of oxygen exchange between themselves and the fetus, the need for more oxygen than non-pregnant, easy to appear wheezing It is more difficult to breathe, especially after labor. Generally speaking, the heaviest burden on the heart is around 32-34 weeks. It is recommended that pregnant women pay attention to rest in late pregnancy, and try to take a left-sided position when resting and elevate the upper body appropriately, which can effectively relieve the symptoms; 4. abnormal cardiac function and related diseases: if the above symptoms do not improve after treatment, or the symptoms of breath-holding are very serious, with increased heart rate, cough and other accompanying symptoms, then consider whether there is perinatal cardiomyopathy and severe malnutrition, heart failure and so on. Prompt medical consultation should be made for laboratory tests and examinations of the heart and lungs, and then appropriate treatment should be given for the cause. In order to ensure the health of the pregnant woman and the fetus during late pregnancy, it is necessary to pay attention to proper rest and exercise, to strengthen the air circulation in the space you are in, and to send you to the hospital if necessary.