Endometriosis affects approximately one in ten women of childbearing age and may involve both acute pain related to the menstrual cycle and chronic pain. Usual analgesic therapy is often inadequate and/or involves unacceptable side effects and risks with long-term use. Transcutaneous electrical nerve stimulation (TENS) is a patient controlled treatment for pain relief with few side-effects. To date there is limited knowledge of how TENS treatment should be carried out for optimal pain relief in this patient group. The aim of the study is asses the effect of TENS as add-on treatment compared with conventional analgesic treatment in patients with endometriosis-related chronic pain. Patients with frequent pain and high pain intensity (≥ 4 according to Numeric Rating Scale, NRS) will be randomized to additional treatment with TENS or conventional treatment for 8 weeks in order to evaluate the acute effects of TENS treatment (n=40). Patients with endometriosis-related pain that is not frequent or without high pain intensity constitute an external control group. All patients in the study will receive TENS treatment for a total of 16 weeks, for evaluation of long-term effects of TENS treatment in chronic endometriosis-related pain. Prior to start of TENS treatment, all patients receive education on chronic endometriosis-related pain and TENS treatment. Study participants will be asked to participate in a qualitative follow-up within the study including a semi-structured individual interview (n=10-15) before intervention and a semi-structured focus group (n=9-15) interview after completion of TENS treatment.
The study evaluates the effect of TENS (transcutaneous electrical nerve stimulation) as add-on treatment compared with conventional analgesic treatment in patients with endometriosis-related chronic pain. Patients with frequent pain and high pain intensity will be randomized to additional treatment with TENS or conventional treatment for 8 weeks to evaluate the acute effects of TENS treatment (n=40). Patients with endometriosis-related pain that is not frequent or without high pain intensity constitute an external control group. All patients in the study will receive TENS treatment for a total of 16 weeks, for evaluation of long-term effects of TENS treatment.