The pain in the lower part of the body in the 7th month of pregnancy may be caused by the swelling and pain in the perineum caused by the enlargement of the uterus pressing on the inferior vena cava, resulting in obstruction of the return flow. In this case, you should try to pay attention not to stand for a long time or sit for a long time, and try to pay attention to bed rest, so as to facilitate blood circulation and reduce edema, which can reduce the pain in the lower part of the body. The painful phenomenon also has pathological manifestations, when there is vulvodynia will show vulvar swelling and pain, and also itching symptoms, usually should try to pay attention to hygiene, pay attention to cleaning, to avoid serious infection. If there is pain in the pubic symphysis area, there should be a separation of the pubic symphysis resulting in this phenomenon, this situation requires an ultrasound examination to determine the degree of separation of the pubic symphysis, if the separation is greater than 1cm, it is necessary to timely treatment.