Expression of cannabinoid receptors (CB1 and CB2) has been shown in the endometrial glands of women with endometriosis, whereas no expression is seen in women with normal ovarian tissue.14 Endometriotic lesions found in the ovaries are driven by the cyclic hormonal changes of the body and are the most common source of pain during the menstrual cycle.17 Preclinical studies using animal models have shown promising results regarding antiproliferative effects of cannabinoids on endometriotic lesions, inhibiting the growth and spread of endometrial tissue outside the uterus in animal studies.18 Here, CNR1 is linked to endometriosis.