Estrogen requirements in girls with Turner syndrome; how low is enough for initiating puberty and uterine development?

We conducted this study to find the adequate initial estrogen dose for adolescent girls with Turner Syndrome (TS). We reviewed the medical records of 19 girls with TS and premature ovarian failure (POF), aged 13 to 17 years, who were referred to our adolescent gynecology clinic for ERT. Nine patients were treated with 0.5 mg estradiol valerate (EV) and 10 patients were treated with 1 mg EV as an initial estrogen dose for 1 year. Breast development, changes in uterine size and bone mineral density were measured before and after 1 year of ERT. All patients showed breast budding after 1 year of ERT regardless of estrogen dosage. Uterine development in patients treated with 1 mg EV advanced farther in 1 year of treatment than in patients given 0.5 mg EV. In patients treated with 1 mg EV, uterine length increased by 39.8% and AP fundal diameter by 46%, increments greater than in patients receiving 0.5 mg EV. After 1 year of ERT, bone mineral densities (BMD) increased significantly in both groups, although BMD did not differ significantly between the groups. In conclusion, ERT with 1mg of EV, as a starting dose induced better uterine development than 0.5 mg in prepubertal girls with TS.