Early initiation of growth hormone treatment allows age-appropriate estrogen use in Turner's syndrome

Because estrogen (E) accelerates skeletal maturation it can decrease final height attainable with GH therapy in girls with Turner's syndrome (TS). Non etheless, as age-appropriate E administration does have psychobehavioral be nefits for such patients, we asked whether E treatment in TS could occur wi thout adverse impact on final adult height if GH therapy were started at an earlier age. Near adult height (NAH) was assessed in 344 girls with TS, wh o had received both GH and E and were followed in the National Cooperative Growth Study database. The groups were divided into quartiles based on age at initiation of GH (2-10, 10-12, 12-14, and 14-18 yr). The longest total a nd E-free period of GH treatment occurred in the girls who had started trea tment in the youngest quartile (mean age, 8.2 +/- 1.5 (SD) yr); they were a lso exposed to E at the youngest age (12.7 +/- 1.6 yr). Although the girls in the youngest group received E at an earlier age, they had a significantl y greater increase (1.8 +/- 0.8) in Lyon height so score at NAH over Lyon p redicted adult height than those in the oldest GH-treated group (0.8 +/- 0. 6), which first received E at 15.9 +/- 1.3 yr. Multiple linear regression e quations for gain in Lyon height so score and in height (cm) showed greater increments with a longer period of E-free GH therapy. All four GH age grou ps had the same NAH, but the youngest quartile was youngest at NAH and like ly still having more growth potential. Comparable data were found in 127 TS girls with spontaneous puberty. In conclusion, girls with TS starting GH a t an early age have a greater gain in Lyon so score at NAH compared with th ose starting later, even though they received E at a younger age. If GH the rapy were started early, E treatment could be initiated at a younger, more age-appropriate time without compromising adult height.