In general, lower back and leg pain during pregnancy is often due to the posterior tilt of the uterus in early pregnancy, which compresses the rectum and ligaments, and in mid to late pregnancy, due to the increase in the abdomen, which leads to an increase in the physiological curvature of the spine, and the continuous tension of the back muscles, which causes fatigue of the lower back muscles, all of which can lead to lower back and leg pain. However, back and leg pain during pregnancy is a normal physiological phenomenon and there is no need to worry too much about it.