Long-term Growth and Skeletal Effects of Early Growth Hormone Treatment in Turner Syndrome

This is an extension study that will gather long-term data on the effect of early growth hormone (GH) treatment on adult height and other aspects of health and development in girls with Turner syndrome. The main purpose is to determine whether girls who received 2 years of GH treatment before 6 years of age achieve taller adult height than girls who were untreated during this time. The study will also look at middle ear and hearing function, and cognitive and behavioral development. Protocol completion is defined as attainment of height velocity less than or equal to 1.0 cm/year, or bone age greater than or equal to 15 years.