In women, the vagina and urethra are located in the vestibular area of the external genitalia, with the urethral opening above and the vaginal opening below, flanked by the labia minora. Both the urethra and vagina are made of epithelial and muscular tissue, and it is the urethra that communicates with the bladder, through which urine flows out of the body. Behind the urethra is the vagina, below the vaginal opening is the anus, the vagina is located in front of the rectum, the vagina is connected to the cervix and wraps around a part of the cervix, forming the fornix, where the posterior fornix is the best place for puncture, this position is also the lowest point of the pelvis, where pelvic fluid, pus and bleeding from ectopic pregnancy collect, there are circular folds in the vagina, which increase significantly in length and width when excited, especially During labor, it facilitates the smooth delivery of the fetus.