If the pain in the tailbone is only when the menstruation comes, it may be due to the congestion of blood in the pelvic cavity when the menstruation comes, which causes pain in the menstrual period, and also causes pain in the sacral tailbone. You can take oral medication to activate blood circulation and eliminate blood stasis, reduce swelling and pain, such as Yuanhu pain relief tablets. If the pain cannot be relieved, oral non-steroidal anti-inflammatory drugs, such as ibuprofen extended-release tablets, are needed for pain relief. It may also be caused by cold or chill when menstruation comes, so you need to keep warm and do not drink cold drinks or eat ice cream when menstruation is coming. Drink more hot water when menstruation comes, and put on a warming patch. If the inflammation of the pelvic cavity stimulates the surrounding mucous membrane and nerves for a long time, it may also cause pain in the sacrococcyx, so you need to go to the gynecologist in time to check whether there is inflammation of the pelvic cavity. Or if the sacrococcygeal bone is sedentary, it may also cause inflammation around it, which may also produce pain.