Clinically, there are many factors that cause women to have weak legs during menstruation, which may be caused by the following factors: 1. Patients do not need to worry too much and should pay attention to nutrition and rest during menstruation; 2. It may be caused by diseases, for example, when women have a cold or fever during menstruation, they will have symptoms of weak legs, and patients will also have symptoms of upper respiratory tract infection, such as sore throat and runny nose. If the patient only has symptoms of leg weakness during menstruation and there are no other accompanying symptoms, usually no treatment is needed and the symptoms of leg weakness will disappear with the end of menstruation.