Subdermal progestin implant (Nestorone) in the treatment of endometriosis: clinical response to various doses.

Objective: To evaluate the efficacy of three different doses of Nestorone progestin administered by implants for relief of pain, as well as bleeding patterns and symptoms in women with endometriosis.

Design: An open clinical study without a control group.

Patients: Twenty-one women in whom endometriosis was diagnosed and treated at laparoscopy or at laparotomy.

Interventions: The patients were randomly allocated to one of three groups receiving a daily dose of either 150 micro g, 200 micro g or 400 micro g Nestorone for two to four implants inserted subcutaneously for 7 months. After removal of the implants the follow-up period was 6 months. Six patients in the 150 micro g group, seven in the 200 micro g group and five in the 400 micro g group completed the study.

Measurements: Records of bleeding and registered side-effects and endometriosis-related symptoms were kept by the patients. Ovarian status was evaluated by vaginal ultrasonography. Serum concentrations of Nestorone and of lipids were measured.

Results: Pelvic pain decreased significantly in response to the treatment in all groups but returned to pretreatment levels during the post-treatment period. Bleeding and spotting was the most common side-effect followed by hypoestrogenic and psychic symptoms, with no significant difference among the groups. No significant changes in the serum levels of total, HDL or LDL cholesterol were found. One patient during the treatment period and four patients during the follow ups underwent surgical procedures.

Conclusion: All three doses of Nestorone effectively alleviated endometriosis-related pain. While the Nestorone implant provides an interesting option for the treatment of endometriosis-related pain, its role needs to be assessed in comparative trials.