Leuprolide acetate gonadotrophin response patterns during female puberty.
OBJECTIVE
To assess normative data and the usefulness of spontaneous and LHRH analogue-stimulated serum LH and FSH levels measured by immunoradiometric assays (IRMA) in the evaluation of normal puberty.


METHODS
Prospective. Healthy girls in Tanner I and Tanner II from the local community were invited to participate (n = 47).


METHODS
A leuprolide acetate test (500 mcg/m(2); sc) was performed. LH and FSH levels were determined using IRMA. Tanner II girls were assessed every 6 months until Tanner V. Girls who progressed from Tanner II to Tanner III in the next 6 months were called Tanner II-2; otherwise, they were called Tanner II-1.


RESULTS
The prepubertal upper limit (CI 95%) was 0.49 IU/l for basal LH and 5.1 IU/l for stimulated LH. Taking into account these LH cut-off limits, 72.2% and 66.7% of Tanner II-1 and 41.6% and 41.7% of Tanner II-2 subjects presented overlapping values for basal and stimulated LH, respectively, as compared with the Tanner I group. The cut-offs for basal and stimulated LH to predict progression from Tanner II to Tanner III in the next 6 months were a basal LH level > or =0.49 IU/l (Sensitivity = 0.58; 1-Specificity = 0.33) and a poststimulated LH level > or =4.75 IU/l (Sensitivity = 0.67; 1-Specificity = 0.44).


CONCLUSIONS
According to an IRMA, the basal and leuprolide acetate gonadotrophin response patterns during the beginning stages of puberty overlapped between Tanner I and Tanner II, and the cut-offs of basal and stimulated LH levels to predict progress from Tanner II to Tanner III had low sensitivities for the following 6 months.
Martinez-Aguayo
A
A
Paediatric Department, School of Medicine, Pontificia Universidad Catolica de Chile, Santiago, Chile. vmericq@med.uchile.cl
Hernández
M I
MI
Capurro
T
T
Peña
V
V
Avila
A
A
Salazar
T
T
Asenjo
S
S
Iñiguez
G
G
Mericq
V
V
D019540:Area Under Curve; D002648:Child; D002675:Child, Preschool; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood*; D006801:Humans; D016729:Leuprolide; D008137:Longitudinal Studies; D007986:Luteinizing Hormone / Q000097:blood*; D011627:Puberty / Q000502:physiology*; D012680:Sensitivity and Specificity
D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D016729:Leuprolide