The common causes of armpit pain in female patients when they are pregnant are mainly the following: a. The exuberant level of estrogen and lactogen in the patient’s body can cause congestion and hyperplasia of the mammary glands and cause radioactive pain in the armpit. At this time, the patient can massage the acupuncture points of the breast, apply hot ointment pack externally, fumigate with moxibustion strips, maintain a light diet and regular sleep, so as to alleviate the symptoms of mammary gland hyperplasia, which can effectively relieve the axillary radioactive pain; second, for female patients with axillary parametrium, during pregnancy, due to the increased secretion of estrogen and lactogen, it will cause the development of axillary parametrium hyperplasia resulting in axillary pain. Patients can undergo surgery to remove the axillary parametrium completely to relieve the axillary pain and also to avoid the occurrence of cancer in the axillary parametrium, which can cause serious complications.