Pertubation with lignocaine as a new treatment of dysmenorrhea due to endometriosis: a randomized controlled trial.

BACKGROUND Endometriosis is a chronic inflammatory disease of unknown aetiology that can cause severe dysmenorrhea. Lignocaine has anti-inflammatory properties and exerts effects on nerve endings and intra-peritoneal macrophages. The objective of this study was to evaluate the effect of pertubation with Ringer-Lignocaine on dysmenorrhea in women with endometriosis. METHODS A double-blind randomized controlled trial (RCT) was carried out at three sites in Stockholm, Sweden. Eligible patients had endometriosis as diagnosed by laparoscopy, dysmenorrhoic pain >VAS 50 mm (visual analogue scale) and patent Fallopian tubes. The study patients were randomized sequentially to preovulatory pertubations with placebo (n= 18) or study treatment (n= 24) during three consecutive menstrual cycles. The pertubation procedure comprised passing study solution through the uterine cavity and the Fallopian tubes via an intra-cervical balloon catheter. The effect on pain was evaluated with VAS scales before and after the treatments and up to nine menstrual cycles after the last pertubation. Success was defined as a reduction of ≥ 50% on the VAS scale after the third pertubation. The success rate between the treatment and the placebo group was compared with Fisher's exact test. RESULTS In the intention-to-treat analysis, the success rate was 41.7% (10 of 24) in the treatment group compared with 16.7% (3 of 18) in the placebo group (P= 0.10, 95% CI -7.3 to 36.2%). In the per protocol analysis, the success rate in the treatment group was 45% (9 of 20) compared with 7.1% (1 of 14) in the placebo group (P= 0.024, 95% CI -2.6 to 44.8%). Of the nine patients in the lignocaine group who fulfilled the criteria for success after three pertubations, 4 (44%) had an effect persisting after nine months. The treatments were well tolerated. CONCLUSIONS This small RCT indicates that pertubation with lignocaine is a non-hormonal treatment option for patients with dysmenorrhea and endometriosis. ClinicalTrials.gov identifier: NCT01329796.