Overnight luteinizing and follicle stimulating hormone profiles during GnRHa treatment in short girls born small for gestational age.

BACKGROUND: Since puberty starting at a height less than 140 cm might reduce adult height, postponement of puberty was studied in short pubertal girls born SGA. Data on overnight LH and FSH profiles during GnRHa treatment are very limited.

AIMS: To evaluate whether 3 months of GnRHa treatment results in sufficient suppression of pubertal LH and FSH profile patterns. To evaluate whether girls show sufficient pubertal suppression according to a consensus-based peak LH cut-off level of 3 IU/l during a GnRH agonist test.

PARTICIPANTS: Twenty-one short pubertal girls born SGA.

INTERVENTION: After baseline LH and FSH profiles, children received leuprorelide acetate depots of 3.75 mg subcutaneously, every 4 weeks.

RESULTS: At baseline, amplitude and frequency of LH and FSH pulsatility were higher in girls with breast stage 3, compared to girls with breast stage 2. After 3 months of GnRHa treatment, all girls showed clinical arrest of puberty and their LH and FSH levels during overnight profiles had significantly decreased to prepubertal levels. In contrast, peak LH during the GnRH agonist test indicated insufficient pubertal suppression in 33% of girls. No differences in LH and FSH profiles were found between girls with a peak LH above or below 3 IU/l.

CONCLUSION: After 3 months of GnRHa treatment, central puberty was adequately suppressed in all girls, as shown by the prepubertal LH and FSH profiles. The GnRH agonist falsely indicated insufficient pubertal suppression in 33% of these girls.