Serum levels of antimüllerian hormone in early maturing girls before, during, and after suppression with GnRH agonist

ObjectiveTo evaluate whether serum antimüllerian hormone (AMH) levels are affected in early maturing girls, and whether pituitary suppression by long-acting GnRH agonist (GnRH-a) affects AMH.DesignSecondary analyses of a prospective clinical study.SettingTertiary pediatric center.Patient(s)Fifteen girls followed during GnRH-a treatment. Evaluations before, 3 and 12 months after initiation, as well as 6 months after discontinuation of treatment. To evaluate whether AMH levels were affected in early maturing girls, baseline levels were compared with levels in healthy girls (matched for age, n = 129; matched for pubertal Tanner stage, n = 119).Intervention(s)Patients were treated with SC injections of leuprolide acetate (LA; Procren 3.75 mg every 28th day).Main Outcome Measure(s)Basal serum levels of AMH, E2, inhibin B, FSH, and LH, as well as GnRH-stimulated levels of FSH and LH.Result(s)At baseline, the median (range) of AMH levels in the patients was 20.3 pmol/L (2.0–30.0 pmol/L). After 3 months of GnRH-a treatment, AMH declined to 10.4 pmol/L (range, <2.0–27.0 pmol/L). The AMH suppression was maintained after 12 months of treatment (14.4 pmol/L [range, <2.0–29.6 pmol/L]). Six months after discontinuation of GnRH-a treatment, AMH levels were similar to pretreatment levels (18.8 pmol/L (range, 5.8–46.9 pmol/L)). Before treatment, AMH levels in early maturing girls did not differ significantly from AMH levels in healthy age-matched girls (median, 20 vs. 23 pmol/L) or Tanner-matched girls (median, 20 vs. 19 pmol/L).Conclusion(s)The partial suppression of AMH by GnRH-a treatment is consistent with previous studies suggesting partial gonadotropin-dependence of AMH.