Leukemia Inhibitory Factor a Marker of Implantation Success in Unexplained Infertility: a Randomized Controlled Trial

Background: Uterine receptivity and implantation are complex processes requiring coordinated expression of mol-ecules by zygote and uterus. Leukemia inhibitory factor (LIF) is one of the most important cytokines in the repro-ductive tract. Without expression of LIF in the uterus, implantation of a blastocyst cannot begin. Our objectives were to measure the leukemia inhibitory factor (LIF) concentration in serum with or without endometrial scratch-ing in women with unexplained infertility.Methods: This study is a randomized control trial, carried out at the infertility clinic of Qena University hospital, South Valley University, Egypt. The study included 200 women with unexplained infertility divided into two groups: Group 1 included 100 patients undergoing endometrial scratching at mid luteal phase. Group 2 included 100 patients undergoing expectant management. Serum leukemia inhibitory factor (LIF) concentration was mea-sured at mid-luteal phase of cycle and follow up of pregnancy occurrence in both groups.Results: LIF was significantly higher in the group of endometrial scratching compared to group 2. LIF was signifi-cantly higher in pregnant women compared to non-pregnant ones in both the endometrial scratching group and group 2. For the endometrial scratching group, LIF was a significant marker for successful implantation at cutoff point of 97.2 with sensitivity of 97.3% and specificity of 77.8% while PPV was 72% and NPV was 98.Conclusions: Endometrial scratching was associated with higher level of LIF and pregnancy rate. LIF was signifi-cantly higher in pregnant women with or without endometrial scratching.