Shortness of breath during pregnancy is mainly due to the fact that during pregnancy, as the foetus develops, the uterus increases in size, the uterus squeezes its surrounding organs, causing the abdominal organs to move upwards, the heart, diaphragm and lungs are also subjected to overhead pressure, and the rise and fall of the chest increases, which will gradually make up for the lack of breathing. Meanwhile, pregnant women can have electrocardiograms and heart ultrasound examinations to clarify whether there is any combined heart disease.