When menstruation occurs, lumbago and leg pain may be related to the following factors: 1. physiological reactions, such as the pelvic cavity is congested when menstruation occurs, which will inevitably have a certain impact on the blood circulation of the lower limbs, and individual women who are more sensitive will experience leg pain and lumbago, it is recommended to take proper rest, and it is best to soak your feet in hot water every night before going to bed, and elevate your lower limbs during sleep to reduce the symptoms. 2. It may be caused by pathological reasons, such as large pelvic tumors, and the pelvic cavity is in a congested state when menstruation comes, which can lead to pain in the legs and lumbar area by compressing the blood circulation of the lower limbs, and can be clearly diagnosed through gynecological examination and ultrasound. If there is pelvic tumor, it is recommended to give surgery for treatment in time.