A hole in the pregnant breast squeezing out a lot of blood may be due to folliculitis, mastitis, breast cancer and other diseases. 1. Folliculitis: Folliculitis may be caused by skin trauma, low immunity, pathogen infection, excessive sweating and other factors. Patients may have red papules with white pustules on top, accompanied by itching and tenderness. Pregnant women may have a hole in the breast, which can bleed a lot when squeezed. 2. Mastitis: Mastitis can be caused by bacterial infections, changes in hormone levels and other factors. Patients may experience symptoms such as nipple inversion and nipple discharge. When secondary infection occurs, the small blood vessels of the mammary glands are damaged, which may result in a lot of blood flow when the patient squeezes the nipple. 3. Breast Cancer: The cause of breast cancer is not yet clear, it may be caused by heredity, over-nutrition, obesity, high-fat diet and other factors. Patients may have nipple discharge, and the nature of the liquid is mostly bloody and plasma, which is manifested as a hole in the breast to squeeze out a lot of blood. In addition, the dilatation of breast ducts lead to capillary rupture may also appear similar clinical manifestations, leading to a hole in the breast during pregnancy to squeeze out a lot of blood for a number of reasons, it is recommended that the patient to go to the hospital to find out the cause of the disease.