ESPE Abstracts (2014) 82 P-D-1-1-201

The Effect of 17[beta]-Estradiol on Uterine Volume in Young Women with Turner Syndrome: a 5-Year Randomized Controlled Clinical Trial

Line Cleemanna, Kirsten Holma, Eva Fallentinb, Nini Møllerc, Bent Kristensend,e, Sven Oluf Skoubyf, Per Leth-Esbensend, Eva Mosfeldt Jeppeseng & Claus Gravholth,i

aDepartment of Pediatrics, 3400 Hillerød, Denmark; bDepartment of Radiology, 2100 Copenhagen, Denmark; cDepartment of Gynecology and Obstetrics, 3400 Hillerød, Denmark; dDepartment of Radiology, 3400 Hillerød, Denmark; eDepartment of Medical Research, 3400 Hillerød, Denmark; fDepartment of Gynecology and Obstetrics, 2730 Herlev, Denmark; gDepartment of Pediatrics, 2730 Herlev, Denmark; hDepartment of Endocrinology and Internal medicine, 8200 Aarhus, Denmark; iDepartment of Molecular Medicine, 8200 Aarhus, Denmark

Background: The majority of Turner syndrome (TS) girls need exogenous estrogen treatment to induce normal uterine growth. The optimal estrogen treatment protocol has not been determined.

Objective and hypotheses: To compare the effect of two different dosing regimens of oral 17β-estradiol on uterine size with the hypotheses that most girls with TS would benefit from a higher dose.

Method: A double-blind 5-year randomized controlled clinical trial. The lower-dose group (LD group) took 2 mg 17β-estradiol/day orally and placebo. The higher-dose group (HD group) took 2+2 mg 17β-estradiol/day orally. 20 young TS women (19.2±2.5 years, range 16.0–24.9) participated. The uterus was investigated by transabdominal ultrasound (US) and magnetic resonance imaging (MRI) at baseline and yearly thereafter.

Results: A steep increase in uterine volume within the first years of treatment was seen in the HD-group by US and MRI. In the LD-group a less steep increase in uterine volume was seen by US. In the LD-group the uterine volume remained statistically unchanged from baseline and throughout the follow-up by MRI. The uterine volume remained stable in the subsequent years in both groups and at the last visit there were no significant differences in uterine volume between the two groups.

Conclusion: High dose oral 17β-estradiol induces a steeper increase in uterine volume in young women with TS within the first years of treatment compared to the lower dose. The uterine growth potential seems to be the same in most young women with TS making the duration of treatment equally significant as estrogen dose.