Chest tightness and nausea may be caused by pregnancy, but it may also be caused by gastrointestinal diseases, respiratory diseases and cardiovascular diseases, which need to be analyzed according to the specific situation, and we cannot rely solely on this symptom to determine whether the patient is pregnant, as follows: 1. Pregnancy: For women of childbearing age, if they have had sex before and have not taken any contraceptive measures, especially after having sex during ovulation, their menstruation is delayed More than 7 days, symptoms of chest tightness and nausea, accompanied by vomiting, anorexia, breast swelling and other manifestations, consider the possibility of pregnancy. If the morning urine test shows two red bars, the patient is pregnant. If you have doubts about the test result, you can also go to a regular hospital to draw blood to test the content of chorionic gonadotropin in the blood. If the value of chorionic gonadotropin is greater than 5miu/ml, pregnancy can be clearly diagnosed, or you can wait until 42 days after menstruation to do ultrasound and see the gestational sac in the uterine cavity under ultrasound, which can confirm the pregnancy; 2. Other diseases: after excluding pregnancy, the symptoms of chest tightness and nausea symptoms, consider that it may be caused by insufficient blood supply to the heart, or gastrointestinal diseases such as indigestion, gastritis and gastric ulcer, or it may be caused by inflammation of the lung or pneumothorax, and need to go to the hospital for relevant examinations in time to clarify the cause, such as electrocardiogram and dynamic electrocardiogram to clarify the blood supply to the heart, chest X-ray to see if there are diseases of the trachea and lung, and gastroscopy to clarify the presence of stomach inflammation and ulcers, and then determine the appropriate treatment plan.