Spontaneous, but not induced, puberty permits adequate bone mass acquisition in adolescent Turner syndrome patients

Lumbar L2-L4 bone mineral density (BMD) values were measured in 37 adolescent and young adult Turner syndrome patients. Nine had developed spontaneous puberty and had had regular menses since menarche (12.55 years +/- 1.17 years) to the time of BMD evaluation (14.96 years +/- 1.26 years). In the other 28, puberty was induced with increasing doses of oral ethinyl estradiol (2.5-10.0 microg/day, for 2 years) and later administration of estrogen/gestagen therapy up to the time of BMD evaluation. In 18, the adolescent group, menarche appeared at 14.68 years +/- 0.63 years and BMD was evaluated at 17.77 years +/- 0.70 years, and in the other 10, the young adult group, menarche appeared at 14.47 years +/- 0.53 years and BMD was evaluated at 20.90 years +/- 0.68 year. BMD values were in the normal range in those who had developed spontaneous puberty (Z score values, -0.24 +/- 0.22) and in the osteopenia range in those in whom puberty was induced (Z score values, -2.09 +/- 0.79 and -2.18 +/- 0.32 for the adolescent and young adult groups, respectively) p < 0.0001. Height Z score values were similar in all three groups (-3.45 +/- 0.77, -3.15 +/- 0.83, and -3.08 +/- 0.33, respectively). No significant differences in calcium intake or physical activity were found among groups. Neither the karyotype distribution nor growth hormone (GH) therapy (five in the spontaneous puberty and six in the induced puberty groups had been treated for a 3.5- to 4.4-year period) explained the differences in BMD values. Because the main difference between groups was the availability of estrogens to bone tissue from infancy to menarche and of estrogens/gestagens from then on up to the time of BMD evaluation, our results suggest that normal gonadal function from infancy to adulthood may be required for adequate bone mass peaking. Early detection of osteopenia and improvement in general measures for adequate bone mass peaking (calcium intake and physical activity) should be considered mandatory in the health care of these patients.