The primary objective of this pilot study is to evaluate the efficacy of trace elements, versus placebo, on the reduction of pain in endometriosis of an American Fertility Society (AFSr) score of 2 to 4, combined or not to an adenomyosis, during a chronic treatment of 4 months.

The objectives of this pilot study are to evaluate the efficacy of trace elements, versus placebo, on the reduction of pain, on the quality of life, on the use of rescue medication (ibuprofen) in patients with an endometriosis of an American Fertility Society (AFSr) score of 2 to 4, combined or not to an adenomyosis, during a chronic treatment of 4 months. The safety of trace elements versus placebo will also be assessed.

This will be a prospective, interventional, randomized, placebo-controlled, two parallel-group, double-blind study.

Trace elements or placebo are administered in the absence of any other treatment or as add-on treatments to common therapies such as sexual hormones, anti-inflammatory drugs or surgery.

A run-in placebo period of 30 days will allow eliminating the patients who are responding to strongly to a placebo.

The treatment will last for 4 months. The total duration of the study will be 5 months for each patient. Four medical visits (Days -45 to -30, 0, 60 and 120) and two phone contacts (Days 30 and 90) will be scheduled.

A urine pregnancy test will be undertaken at each visit. The quality of life scale (EHP-30) will be filled in on Days 0, 60 and 120. During the whole study period, patients will be asked to fill in a diary, in which they will score their pain on a visual analog scale, their blood loss and their consumption of rescue medication (ibuprofen).

Phone contacts will be used to reinforce the compliance and to collect potential adverse events.

Non-serious and serious adverse events will be collected between Days 0 and 120.

All concomitant medications will be recorded, including the rescue medication between Day -45 and Day 120.

A paper case report form will be used.

A total of 60 patients (30 receiving trace elements and 30 receiving placebo) will be randomized to achieve a total of 50 patients.

Inclusion Criteria:

• Written informed consent
• Woman suffering from an AFSr 2 to 4 endometriosis (combined or not to an adenomyosis), confirmed by laparoscopy, laparotomy or MRI as well as by a biopsy (done within 3 years before inclusion in the study), treated or not with sexual hormones, contraceptive or not (stable treatment for minimum 2 months) or any other treatment
• Time period of at least 6 months after surgical treatment
• Age between 18 and 45 years
• Non-menopausal woman
• Baseline pain (Day -45 to -30) of at least 40 mm on a visual analog scale
• No reduction of more than 20% of pain on the visual analog scale after the run-in placebo period.

Exclusion Criteria:

• AFSr 1 endometriosis
• Adenomyosis without endometriosis
• Pregnancy
• Existence of another pathology that could interfere with endometriosis and/or with adenomyosis, and the study follow-up
• Psychological or psychiatric conditions
• Patient who, according to the investigator, will not be able to comply to the prerequisites of the study.