Sudden shivering in the morning can be caused by environmental factors, as well as pathological factors such as infections, low blood pressure, mastitis, and so on. 1. Environmental factors: because of the relative weakness of the maternal body during the month, if in a cold environment or by the cold air, there may be a sudden shivering of the symptoms, and do a good job of keeping warm after the symptoms can be gradually relieved. 2. Pathological factors (1) Infection: Shivering during menstruation may be a pre-febrile chills caused by infectious diseases. ①Reproductive tract infection: If you don’t pay attention to the local cleanliness of the vulva during the puerperium, it can cause reproductive tract infection, fever, chills, and may also be accompanied by vaginal discharge odor, lower abdominal pain and other symptoms. ② Upper respiratory tract infection: sweating more during puerperium, easy to catch a cold and other upper respiratory tract infections, manifested as fever, shivering chills and other symptoms. (2) Hypoglycemia: During menstruation, mothers may have a poor appetite and eat less, thus causing hypoglycemia, which can be manifested as sudden shivering and chills all over the body, and the symptoms are usually relieved gradually after taking sugar water. (3) Mastitis: Breastfeeding during menstruation can lead to the accumulation of milk in the breasts due to the lack of breast care, which can further lead to inflammation of the mammary glands, causing localized redness, swelling and pain in the breasts. It can also cause fever and chills. If you experience shivering during menstruation, it is recommended that you consult a doctor in time to find out the cause of the shivering and then actively treat it to avoid delaying your condition.