Depending on findings, laboratory tests for other causes of slow growth should be considered: Hypothyroidism (eg, thyroid-stimulating hormone, thyroxine) Renal disorders (eg, electrolytes, creatinine levels) Inflammatory and immune conditions (eg, tissue transglutaminase antibodies, C-reactive protein) Hematologic disorders (eg, complete blood count with differential) Criteria for delayed puberty Although many children seem to be starting puberty earlier than in past years, there are no indications that the criteria for delayed puberty should change.