CNR2 and adenomyosis: When matched samples of the eutopic and ectopic endometrium of subjects diagnosed as adenomyosis were compared, the CB2 immunoreactivity was much lower in the ectopic endometrium than in the eutopic endometrium (for the proliferative phase P < 0.001; for the secretory phase P = 0.001) (Figures 2(j) and 2(k)).