KITLG and endometriosis: In the case of patients in the mild endometriosis group, the mean level of s-SCF was significantly lower on the 8th day of stimulation (28.1 pg/ml vs. 49.1 pg/ml; MWU test, p < 0.05) and on the oocyte retrieval day (33.4 pg/ml vs. 50.4 pg/ml; MWU test, p < 0.005) in samples from patients who had at least one TQ blastocyst on day 5 of culture (Fig. 2B and C).