Update on female pubertal development.
OBJECTIVE
To elucidate recent findings regarding female puberty. The successful completion of puberty is a prerequisite for reproduction. Many later disorders of fertility and metabolism may develop during puberty. New more sensitive and specific assays provided us with possibilities for a better understanding of the process of puberty, and the discovery of new factors such as leptin evoked the hope of finding key regulators of the onset of puberty.


RESULTS
The secular trend towards earlier menarche appears now to have come to an end, but discussions about changes in the age of pubertal onset still continue. In a few detected cases of leptin mutations puberty has not occurred spontaneously. The intact secretion of leptin seems to be a necessary prerequisite for the onset of puberty. Apart from that, recent research has indicated that leptin levels mainly reflect body composition. Leptin as well as gonadotropins, steroids and growth hormone shows specific circadian patterns. The 24 h pattern of leptin is similar before and after puberty, but the 24 h pattern of the other hormones changes. The serum concentration of inhibin B increases in the years preceding puberty and in early puberty, whereas inhibin A increases in mid to late puberty.


CONCLUSIONS
The biological significance of the changing circadian patterns remains to be determined. Inhibin B serum concentrations together with follicle-stimulating hormone may indicate remaining potential ovarian activity during childhood in, for example, patients with Turner syndrome, but more information and other possible markers are needed.
Apter
Dan
D
The Sexual Health Clinic, Family Federation of Finland and Hospital for Children and Adolescents, University of Helsinki, Helsinki, Finland. dan.apter@vaestoliitto.fi
Hermanson
Elina
E
D000293:Adolescent; D000367:Age Factors; D002648:Child; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D007265:Inhibins / Q000502:physiology; D020738:Leptin / Q000502:physiology; D008572:Menarche / Q000502:physiology; D011627:Puberty / Q000502:physiology*
D020738:Leptin; C422364:inhibin B; D007265:Inhibins