The pubic symphysis is located in the upper part of the labia majora on both sides, below the pubic mound, and is formed by the joint surface of the pubic bone on both sides by means of the fibrocartilage connection, reinforced by the suprapubic ligament and pubic arcuate ligament. When a woman is pregnant, especially in the third trimester of pregnancy, the embryo is growing and developing in the uterine cavity, at this time the fetus is small, and after the third trimester of pregnancy, in the pubic symphysis above the uterus will be touched to the enlarged, you can initially determine the number of weeks of pregnancy, which can be an aid in determining the role of the week of pregnancy.