How is pelvic Ultrasound used in the evaluation of a child with precocious puberty?
Uterine and ovarian volumes are larger than normal in true isosexual precocious puberty, whereas enlargement of only the ovary has been reported with pseudosexual precocity. True isosexual precocity is due to the premature activation of the hypothalamic pituitary gonadal axis, whereas pseudosexual precocity refers to pubertal changes occurring independent of these actions, as in the case of a functional ovarian cyst or tumor. Multiple, small (<1 cm) cysts can be seen in the ovaries of normal children and in children who have precocious puberty. The best predictor of true precocious puberty is bilateral ovarian enlargement, but unilateral ovarian enlargement associated with larger cysts is more related to pseudosexual precocity.