The uterine cavity is very different from the uterus and is inseparable. The uterine cavity is wide at the top and narrow at the bottom, triangular in shape, with a capacity of about 5 ml, connected to the fallopian tubes on both sides and to the cervix at the lower end, and is part of the uterus, which is normally covered by the endometrium. The uterus consists of the uterine cavity and the cervix and is located in the middle of the female pelvis. The uterus is the place where life is conceived and where the embryo grows and develops, and is influenced by ovarian sex hormones, and the endometrium undergoes cyclic changes to produce menstruation. Normally, the uterus has an inverted pear shape. The uterus is a single muscular organ composed of smooth muscles with a very rich expansibility, and after pregnancy the uterus increases in size and the uterine cavity also increases in size. The shape and size of the uterus, as well as its position and related structures, change according to the woman’s age and are also affected by the woman’s menstrual cycle as well as by pregnancy.