There are several causes of leg pain in the fifth month of pregnancy. Due to the hormonal imbalance in the body during pregnancy, muscle aches and pains may occur. During pregnancy, the fetus grows and the uterus enlarges, compressing the inferior vena cava and causing obstruction to the return flow, which may also lead to leg aches and pains. If you do not take calcium supplements during pregnancy, you may experience leg cramps or muscle pains during the process of calcium deficiency. It is necessary to determine the condition according to the symptoms, and then pay attention to maintenance, usually try to pay attention to rest, do not overwork, and also need to pay attention to keep warm. If the dampness and cold will also cause soreness, especially in the middle and late stages of pregnancy, you should promptly replenish calcium, you can drink calcium gluconate, eat calcium tablets for pregnant women, you can also eat foods with high calcium content in the diet.