Is sex hormone priming in peripubertal children prior to growth hormone stimulation tests still appropriate?

Low growth hormone (GH) secretion during puberty may stem from either a permanent GH axis abnormality or from transient GH deficiency secondary to lack of sex hormones. Although well known to enhance stimulated GH secretion in pre- or early puberty, sex hormone priming for the evaluation of the function of the GH-IGF-I axis remains controversial. Many pediatric endocrinologists consider that omission of such priming during the preadolescent period decreases the specificity of GH stimulation tests and increases the percentage of false-positive diagnosis results. Others believe that it leads only to a temporary augmentation of GH secretion followed by a decrease in spontaneous secretion to levels which may be insufficient for normal pubertal growth; thus priming with sex hormones may lead to underdiagnosis of peripubertal children that could have benefited from GH treatment. The increased availability of biosynthetic GH has enabled expanding the indications for GH therapy and judging and renewing the criteria for the diagnosis of GH deficiency, including the practice of sex hormone priming which was and still is executed in clinical use in many centers in the world. We would like to recommend that priming should not be routinely performed in every peripubertal child undergoing GH evaluation but may be considered in adolescents with pubertal delay--girls aged >11.5-12 years and boys aged >13-13.5 years exhibiting no evidence of puberty or only initial signs.