Hormonal factors are poor indicators of endometriosis pain

Endometriosis is a common yet understudied condition in which sex hormones play a key role in the etiology and pathophysiology of the disease. Sex hormones are dysregulated in endometriosis and are pharmacologically targeted to reduce symptoms including pain, but the relationships between endometriosis-related pain with sex hormone levels and their receptors are not clear. In 60 women previously diagnosed or undergoing laparoscopic surgery for the diagnosis of endometriosis, we collected patient-reported endometriosis/pelvic pain intensity in the last 30 days, pain interference scale, and the Endometriosis Health Profile 30 (EHP30) pain subscale. In a sub-sample of 38 participants, biopsies from control non-lesion pelvic peritoneum and endometrial lesion tissues were collected during surgery to analyze the tissue abundance of the primary receptors for estrogen, as well as androgen, progesterone, and prolactin receptors. Serum was collected to analyze systemic sex hormone levels including estradiol, prolactin, progesterone, and testosterone. Between tissues, we found elevated transcript levels for estrogen receptor alpha (ESR1) in lesions, but no difference in estrogen receptor beta (ESR2) transcript levels between tissue samples were found. Relating tissue receptor transcript levels to clinical pain revealed that only ESR1 and PGR in lesions were negatively associated with endometriosis/pelvic pain intensity, however, following false discovery rate correction the association with ESR1 was no longer statistically significant. No other tissue or systemic factors were associated with clinical pain outcomes. Together, these data demonstrate unique alterations in receptor abundance in lesions yet select transcript levels only weakly relate to pain in endometriosis.