The role of leukaemia inhibitory factor in the establishment of pregnancy

Leukaemia inhibitory factor (LIF) is a pleiotrophic cytokine required for b lastocyst implantation in mice. Uterine expression of LIF and that of its r eceptors has been demonstrated in a number of mammalian species indicating that LIF may have widespread importance in the establishment of pregnancy. The variations in the reaction of the uterus in preparation for and during implantation are considerable between species and understanding the differe nces and similarities assists in the interpretation oi how this cytokine fu nctions. Recent studies suggest that reduced endometrial LIF contributes to human infertility. Studies also demonstrate a potential role in placentati on and fetal development. Thus, LIF has become an important cytokine warran ting further investigation in the human. It is anticipated that when the me chanisms underlying normal embryonic and endometrial development are elucid ated, fertility and infertility will be more precisely understood and hence able to be effectively controlled.