Spontaneous pubertal development in Turner's syndrome. Italian Study Group for Turner's Syndrome.

The incidence of spontaneous puberty in Turner's syndrome is reported to be between 5-10% and, more recently in some series, as high as 20%. In an Italian retrospective multicenter study, of 522 patients older than 12 yr with Turner's syndrome, 84 patients (16, 1%) presented spontaneous pubertal development with menarche that occurred at a chronological age of 13.2 +/- 1.5 yr (mean +/- SD) and a bone age of 12.9 +/- 1.9 yr. Karyotype distribution in the whole group was as follows: 52.1% (272 patients) X-monosomy (45,X), 13.2% (69 patients) mosaicism characterized by X-monosomy and cellular line with no structural abnormalities of the second X, 19.9% (104 patients) mosaicism characterized by X-monosomy and cellular line with structural abnormalities of the second X, and 14.8% (77 patients) structural abnormalities of the second X. Menstrual cycles were still regular in 30 patients at 9.2 +/- 5.0 yr after menarche, 12 developed secondary amenorrhea 1.6 +/- 2.0 yr after menarche, and 19 had irregular menstrual cycles 0.9 +/- 1.8 yr after menarche. As signs of spontaneous puberty developed in 14.0% of X-monosomic patients and in 32.0% of patients with cell lines with more than one X, the presence of the second X seems to have a cardinal influence on the appearance of spontaneous puberty. Spontaneous pregnancy occurred in 3 patients (3.6%). The presence of chromosomal abnormalities and malformations in 2 of 3 pregnancies led us to agree with other investigators in discouraging unassisted pregnancies. Treatment with GH does not seem to exert any influence on either the age of onset or the prevalence of spontaneous pubertal development in Turner's syndrome. The increased percentage of spontaneous menarche is Turner's syndrome reported in the recent literature might be due to increased ascertainment by diligent screening for Turner's syndrome in girls with short stature and mild or no Turner's syndrome stigmata, even though they may be menstruating.