Objective: To determine whether there is an association between endometrial expression of leukemia inhibitory factor (LIF) in the luteal phase of the menstrual cycle preceding in vitro fertilization (IVF) and treatment outcome.
Methods: Biopsy specimens from the endometria of 52 women in the luteal phase were immunostained against LIF. Embryo culture and transfer were done according to standard procedures.
Results: Clinical pregnancy occurred in 39% of the women following IVF, and strong endometrial immunohistochemical staining for LIF was associated with pregnancy (P=0.01). The women with a strong LIF expression had a 6.4-fold higher chance of becoming pregnant than those with weaker intensities (P=0.005).
Conclusion: Endometrial expression of LIF during the luteal phase can be used as a predictor of IVF success.