Minipuberty in girls with Turner syndrome provides insight into reproductive potential - a prospective cohort study

Objective: To study reproductive hormone levels during minipuberty in girls with Turner syndrome and compare with girls without Turner syndrome. Design: Prospective cohort study. Subjects: Infant girls with Turner syndrome. Exposure: Blood samples were drawn at 3 and 9 months of age for analysis of reproductive hormones. Karyotype was analyzed in 30 lymphocytes and, if available, in 100 buccal cells. Hormone levels in girls with Turner syndrome were compared with reference values of a control group. Main Outcome Measures: Follicle-stimulating hormone, luteinizing hormone, estradiol, antimüllerian (AMH), inhibin B, and testosterone levels. Results: Fourteen girls with 45,X; five girls with 45,X/46,XX; and four girls with a structural aberration of the X chromosome were included. Follicle-stimulating hormone and luteinizing hormone levels were significantly higher, and estradiol, AMH, and inhibin B levels were significantly lower in girls with Turner syndrome compared with reference values at both time points. In girls with Turner syndrome with undetectable AMH levels, gonadotropin levels increased after 3 months, whereas in girls with Turner syndrome with detectable AMH levels, gonadotropin levels decreased after 3 months to levels within the reference range. Conclusion: Hypothalamus-pituitary-gonadal axis hormone levels during minipuberty in girls with Turner syndrome differ from reference values. The window for assessing ovarian function extends beyond 3 months of age because gonadotropin levels tend to increase in cases with absent ovarian activity, as demonstrated by undetectable AMH, inhibin B, and estradiol levels.