Endometriosis: Leuprolide in a 3-monthly versus a monthly depot formulation for the treatment of symptomatic endometriosis: a pilot study

An open-label randomized pilot study was conducted to evaluate the efficacy and acceptability of 6 months treatment with leuprolide in a 3-monthly versus a monthly i.m. depot injection for the relief of chronic pelvic pain in women with endometriosis. A total of 30 women aged 18-38 years were allocated to the 3-monthly depot arm (n = 15) or to the monthly depot arm (n = 15) after laparoscopic diagnosis of pelvic endometriosis. Mean (SD) deep dyspareunia scores according to a 0-3 point verbal rating scale decreased from 1.8 (0.9) at baseline to 1.3 (0.7) at the end of treatment in the 3-monthly depot group and from 2.1 (1.2) to 1.3 (0.7) in the monthly depot group. Corresponding values in non-menstrual pain scores fell from 2.1 (0.6) to 1.1 (0.3), and from 2.1 (0.8) to 1.2 (0.4) respectively, without statistically significant differences between the groups. Serum luteinizing hormone (LH) and 17β-oestradiol concentrations were significantly suppressed at 12 and 24 weeks compared with baseline values, without differences between the groups. The monthly depot caused a slightly more marked inhibition of serum follicle stimulating hormone (FSH) levels with respect to the 3-monthly preparation. Mean (SD) endometriosis scores at baseline and at 6-month follow-up laparoscopy were respectively 32.8 (25.1) and 12.2 (9.3) in the 3-monthly depot group and 29.0 (22.7) and 13.1 (15.3) in the monthly depot group (paired t-test, P < 0.05). Mean percentage decrease in lumbar spine bone mineral density was 5.2% in the former and 4.9% in the latter subjects. In the 3-monthly depot group, 13 women graded the tolerability of their treatment schedule as 'good' compared with seven in the monthly depot group (X 2 = 5.40, P = 0.02).