Prepubertal ultra-low-dose estrogen therapy is associated with healthier lipid profile than conventional estrogen replacement for pubertal induction in adolescent girls with Turner syndrome : preliminary results

estrogen replacement (LE) therapy in Turner syndrome (TS) have not been fully investigated to date. The present study aimed to compare glucose and lipids metabolism in adolescents with TS on LE and conventional estrogen replacement (CE). Methods In 14 TS (mean age 13.8), LE ($17\beta$-estradiol, 62.5 $\mu$g daily) was introduced before age 12 (mean age 10.5), and followed by a pubertal induction regimen after age 12, and in 14 CE was started after age 12 (mean 14, SD 1.96). Before, and 3 years after starting $17\beta$-estradiol growth velocity, bone age, BMI, and selected parameters of glucose and lipids metabolism were assessed. Results There were no significant differences between LE and CE in the mean levels of any parameter before introduction of $17\beta$-estradiol [total cholesterol (TC): 4.1 vs 4.3 mmol/L, LDL cholesterol (LDLc): 2.2 vs 2.4 mmol/L, HDL cholesterol (HDLc): 1.6 vs 1.4 mmol/L, triglycerides: 0.9 vs 1.0 mmol/L, fasting glucose: 4.2 vs 4.4 mmol/L, post-load glucose: 4.8 vs 5.5 mmol/L; fasting insulin: 6.8 vs 8.0 post-load insulin: 21.3 vs 67.0 $\mu$IU/mL, HOMAIR 1.3 vs 1.6]. After three years of treatment, TC and LDLc levels were significantly lower in LE group (3.8 vs 4.4 mmol/L, p = 0.004; 1.9 vs 2.4 mmol/L, p = 0.03). The other parameters did not differ significantly. There was no negative impact on growth course and bone age advancement nor on BMI in LE group. Conclusion Prepubertal LE is associated with healthier lipid profile than CE in girls with TS.