Breast swelling and nausea without menstruation may be caused by impending menstruation, pregnancy and other reasons. 1. impending menstruation: when menstrual disorders occur after the overdue, due to changes in hormone levels in the body before the impending menstruation, can cause symptoms of breast swelling and pain, but also due to severe menstrual cramps and nausea and other symptoms, through ultrasound, blood or urine HCG (human chorionic gonadotropin) measurements to rule out pregnancy, and may be impending menstruation. 2. Pregnancy: Menopause with breast tenderness, nausea and other symptoms can also occur. Blood or urine HCG tests can be used to determine pregnancy, and ultrasonography can be used to determine if there is an intrauterine pregnancy. There may be other reasons for the lack of breast pain and nausea, so it is recommended to go to the hospital in time to complete the relevant examinations, under the guidance of a professional doctor, to identify the cause of the disease, targeted treatment.