['Uterine expression of leukemia inhibitory factor (LIF) is absolutely essential for mouse, and critical for human, embryo implantation. However LIF is not required for post-implantation development of mouse embryo. The objective of this study was to examine the role of LIF system in post-implantation stage of human pregnancy.', 'Tissues from 25 patients with anembryonic pregnancy (AP; blighted ovum) and 25 matched patients with normal pregnancy (NP) were collected. LIF and its receptor beta (LIF-Rbeta) expression in the decidua and chorionic villi were analyzed by semi-quantitative reverse transcription and polymerase chain reaction (RT-PCR), real-time quantitative PCR and immunohistochemical study.', 'LIF mRNA levels were not different either between different tissues (decidua vs chorionic villi) or between different patients (NP vs AP). LIF-Rbeta mRNA levels were significantly higher in chorionic villi than in decidua but were not different between NP and AP. Immunohistochemical staining supported these findings and showed a predominate expression of LIF-Rbeta in the trophoblast cells.'] Is expression of leukemia inhibitory factor and its receptor altered in the decidua and chorionic villi of human anembryonic pregnancy?