[The significance of leptin for reproduction]

Leptin is mainly synthesized by adipocytes and might represent the connecting link between fatty tissue and brain. In reference to reproduction, leptin resistance could play a role particularly in the pathogenesis of the PCO syndrome. However, there exists at present contradictory data on this, so that further clarification is necessary. Leptin interacts with the steroid synthesis to a degree not yet precisely clarified and possesses receptors in numerous tissues, which suggests extensive local and endocrine effects. Its exact significance for the initiation of puberty still remains unknown. The same is true for first data regarding leptin and endometriosis and the interpretation of hyperleptinemia during pregnancy. It is clear that this protein mediates between fatty tissue and the reproductive function. However, the detailed physiologic and pathophysiologic role of leptin in reproduction can only be clarified through further extensive studies. To date there is not yet a practical importance for the measurement of leptin in routine work in reproductive medicine.