By the time you are more than six months pregnant, your abdomen is already more noticeably bulging, which will push your internal organs elsewhere accordingly and also elevate your diaphragm. The diaphragm is a spacer between our chest and abdominal cavities. If the diaphragm muscle is elevated, it will affect the expansion of the lungs, and dyspnea may occur, especially in certain positions, which is the most common cause of dyspnea after pregnancy. Other less common causes, if the pregnant woman suffers from hypertension, severe hypertension may affect the heart function, thus there are some mild cardiac insufficiency, dyspnea may also occur, and even accompanied by a decline in activity endurance. To summarize the most common is still because of abdominal panglong lead to diaphragm elevation, can pay attention to maintain the position to avoid, but to except cardiopulmonary diseases, if self-treatment can not be relieved, it is recommended that the hospital for consultation, except for other diseases caused by.