Maternal arm soreness, mostly caused by breastfeeding, is treated as follows: 1. improve the breastfeeding posture: generally breastfeeding time should not be too long, you can alternate bilateral when breastfeeding, so you can avoid muscle strain caused by one arm supporting the baby for too long. 2. local hot compresses: for example, you can use infrared irradiation, you can also use hot towels for local hot compresses, which can improve the damaged muscle blood circulation and speed up the recovery of the injury. In addition, you can also carry out appropriate massage, massage, to help reduce muscle spasm, and relieve pain. It is forbidden to take drugs to relieve the symptoms during this period, otherwise it will affect the fetus.