In 21 girls with Turner’s syndrome (TS) without spontaneous puberty treated with growth hormone (GH) the authors evaluated factors which influenced their final height. Special attention was focused on the time of onset of oestrogen substitution. GH treatment was started at the age of 13.1 ± 1.7 years (mean ± SD) and lasted 3.7 ± 1.4 years. The GH dose was 1 IU/kg/week and was divided into 7 injections per week. The period of treatment with growth hormone only („oestrogen free“ interval) was between -3.9 and +4.2 years in relation to the onset of oestrogen substitution. The patients achieved a height of 151.2 ± 6.8 cm. The difference between the attained height and the foreseen height in adult age (calculated by the projection method from Ranke’s standard for TS) was 2.8 ± 5.5 cm. This height increment correlated with the period of GH administration (r = 0.45, p = 0.0008), with the period of GH treatment without concurrent oestrogen substitution (r = 0.28, p = 0.01). The group of girls who were given oestrogens before the onset of GH treatment („oestrogen free“ interval < 0) (n = 8) achieved a final height of 145.1 ± 5.8 cm and their height gain (and loss resp.) was -1.8 ± 3.7 cm, while girls with an „oestrogen free“ interval > 0 (n = 13) had an adult height of 155.0 ± 4.2 cm with a gain of 5.7 ± 4.3 cm. The period of GH treatment and its „oestrogen free“ interval influence by 84% the height gain of girls with TS and are the main predictors of their adult height. Our first group of patients with TS was negatively affected by the late onset of GH treatment and early onset of oestrogen substitution.

        Key words: Turner’s syndrome, adult height, growth hormone treatment, oestrogen substitution