MAPK8 and endometriosis: Non-endometriosis samples had higher ERK1/2 (0.42-fold; p = 0.038 in the secretory phase, and 2.98-fold; p = 0.026 in the proliferative phase) and JNK (2.94-fold; p = 0.002 in proliferative phase) than the eutopic endometrium in the same phase (Figure 2).