Current concepts concerning the role of leptin in reproductive function

Leptin has recently been implicated as having a role in sexual maturation a nd reproduction. This review describes recent findings regarding the putati ve reproductive functions of leptin within the context of the attainment of sufficient long-term fuel reserves to sustain and support pregnancy and la ctation. The review considers the evidence, within the context of the devel opment of hyperleptinaemia during pregnancy, that leptin has an important f unction to modulate maternal nutrient partitioning in order to optimise the provision of nutrients for fetal growth and development. It is suggested t hat, through modulation of maternal insulin secretion and hepatic metabolis m, leptin integrates maternal nutrient storage to the nutrient requirements of the fetus. The importance of the placenta as a site of leptin synthesis and the potential role(s) of placentally derived leptin are evaluated in r elation to maternal-fetal interactions during intrauterine development. The review also examines whether intrauterine growth retardation due to nutrit ional restriction reflects dysregulation of such cross-talk. Finally, the r eview describes emerging evidence for participation of leptin in lactation and neonatal growth. (C) 1999 Elsevier Science Ireland Ltd. All rights rese rved.