General Medical Information

Normal Uterine Development and Size

Andrew S. Cook

The fetal uterus enlarges in response to maternal hormonal stimulation. The infant experiences postnatal regression of uterine size. The size of the uterus remains stable until about 7 years of age. The cervix is larger than the corpus in the young child, resulting in an inverted pear shape of the uterus. The predominance of the cervix over the corpus persists until uterine growth begins at about age 7 years. Both the total uterine volume and the ratio of the corpus to the cervix begins to increase significantly between 6 and 8 years. The normal age-related values of the uterine dimensions, as determined by sonographic evaluation of 114 normal premenarcheal girls.

On CT examination, the uterus was identified in 66% of girls 8 years and under and was identified in 92% of girls over 8 years of age. The size of the uterus was stable until 8 years of age, when a dramatic increase in volume was noted. A range in volume from 0.5 to 1.3 cm3 was observed in the group 8 years and younger. Girls over 8 years of age averaged a uterine volume from 4.1 to 37.3 cm3. Uterine neoplasms in the younger group (rhabdomyosarcoma) and in the older group (hydatidiform mole) were far greater than 2 SD above the age-related controls.