Leukemia inhibitory factor expression in different endometrial locations between fertile and infertile women throughout different menstrual phases.

PURPOSE: The purpose was to demonstrate the leukemia inhibitory factor (LIF) expression in different endometrial locations between fertile and infertile women throughout different menstrual phases. The relationship between progesterone level and LIF expression were evaluated. METHODS: Endometrial biopsies were performed on idiopathic infertile and normal fertile women accepted the in follicular, periovulatory, and luteal phases. The luteal progesterone level was measured. Endometrial LIF immunostaining of luminal epithelium, glandular epithelium, and stroma were detected. The relationship between luteal LIF expression and progesterone level was evaluated. RESULTS: Significant LIF expression was noted in the endometrium of fertile women rather than that of infertile women. The LIF expression was highest in the luminal epithelium, moderate in the glandular epithelium, and lowest in the stroma. The luminal and glandular epithelial staining were lowest in follicular phase, moderate in periovulatory phase, and strongest in luteal phase. The stromal LIF presented with a noncyclical manner. The LIF expression is not related with the progesterone level. CONCLUSIONS: Endometrial LIF expression is related to human fertility. Endometrial LIF expression is dependent on cellular localizations and menstrual stages. Stronger LIF expression presents in the endometrial epithelium during luteal phase.