Study on correlation between LIF expression in endometrium and follicular fluid and pregnancy outcomes during treatment cycle of in vitro fertilization in patients with endometriosis

Objective: To study the expression status of leukemia inhibitory factor ( LIF) in endometrium of implantation window phase and follicular fluid of ovulatory phase in patients with endometriosis,explore the relationship with decrease of pregnancy rate in patients receiving in vitro fertilization embryo transfer ( IVF ET) . Methods: The samples of endometrium from 23 patients with endometriosis were obtained before IVF,and obsolete follicular fluid on the day of ovum pick up was collected; the expression of LIF in endometrium was detected by immunohistochemical SABC method,and the content of LIF in follicular fluid on the day of ovum pick up was detected by double antibody enzyme linked immunosorbent assay,47 women without endometriosis were selected as control group; the expression of LIF and its relationship with embryo development and pregnancy were analyzed. Results: The numbers of retrieved oocytes,fertilization rates,available embryos rates,implantation rates,clinical pregnancy rates in control group and endometriosis group were ( 13. 86 ± 8. 25) and ( 9. 43 ± 7. 12) ,76. 05% and 60. 59%,54. 28% and 34. 47%,26. 53% ( 26/98) and 8. 51% ( 4/27) ,51. 06% ( 24/47) and 17. 39% ( 4/23) ,respectively,there was significant difference between the two groups ( P 0. 05) . The levels of LIF in follicular fluid of ovulatory phase were ( 25. 10 ± 10. 16) pmol/L and ( 14. 68 ± 5. 54) pmol/L,respectively,there was significant difference ( P 0. 05) ; the level of LIF in endometrium of implantation window phase in endometriosis group was significantly lower than that in control group ( P 0. 05) . Conclusion: The decrease of LIF expression levels in endometrium of implantation window phase and follicular fluid of ovulatory phase may be related to infertility induced by endometriosis.