The size of a five-year-old girl’s uterus is about 2cm. A five-year-old girl’s uterus is very much smaller than an adult woman’s because she is still young and her female hormone levels are very low, and in this case the uterus has not yet developed significantly. The size of the uterus of an adult woman is about 7cm long, 4-5cm wide, 2-3cm thick, with a middle volume of about 5ml, which is an inverted pear shape with a slightly flattened front thickness. The upper part of the uterus is wide called the body of the uterus, and the lower part of the uterus is narrower and cylindrical, called the cervix. When still in childhood, the ratio of the cervix to the body of the uterus is different from that of adults, with a ratio of 1:2 in childhood and 2:1 in women of childbearing age.