Abstract

Estimations by radioimmunoassay of the 24-hour excretion of LH in normal children (152 boys and 104 girls) have shown high values in the first six months of life in boys, and possibly girls, and then low levels until the age of about 6 years. There is then a gradual rise in LH excretion in both sexes which continues for the 3-4 years which precede the onset of puberty, at which age a more marked increase occurs. 13 cases of true precocious puberty were all found to be associated with increased urinary excretion of LH, a feature that was seldom shown with other forms of advanced sexual development. Measurement of urinary LH excretion provides a useful tool in the differentiation of such conditions.