Laparoscopic Ablation For Minimal Or Mild Lesions In Endometriosis Associated Subfertility Hesham Al-Inany, M.D kaainih @link.net
Dr Al-Inany is a Senior Lecturer at Cairo University and IVF specialist at the Egyptian IVF-ET Center. He has conducted the first prospective meta-analysis in the entire filed of gynecology comparing GnRH agonist vs antagonist in assisted conception. Dr.Al-Inany is responsible for "Evidence Based Medicine" corner in the Middle East Fertility Society Journal for more than 3 years, explaining the values of evidence based medicine and it tools. He has published over 25 scientific articles since he obtained his medical qualification in Obstetrics & Gynecology in 1998.
Minimal/mild endometriosis could represent a temporary phase in an on-going process that usually results in cytolysis of recently implanted endometrial cells, whereas in a few immunologically 'tolerant' subjects, nodular, cystic and infiltrating lesions develop
Whether minimal endometriosis is a condition that is frequently self-limited or resolves spontaneously or not, we still face a problem. Could ablation of minimal or mild endometriosis be associated with an increase in pregnancy rate. This is the hypothesis to be tested.
Conventional treatments for endometriosis aim to remove or decrease deposits of ectopic endometrium. They achieve this either by inducing atrophy within the hormonally dependent ectopic endometrium, or by destroying the endometriotic implant .
Medical treatment options for endometriosis include hormonal drugs such as the combined oral contraceptive, progestogens, danazol, gestrinone or gonadotrophin releasing hormone analogues for pain relief.
The aim of therapy is to "switch off ovarian function". Their role in infertility treatment has been reviewed in a Cochrane systematic review which concluded that there is no evidence to support their use in women with endometriosis who wish to conceive. (Hughes,1999)
While these approaches continue to be useful for the management of endometriosis associated pain, they may do more harm than good in women whose major concern is fertility. For the six months or more of treatment, women are forced to contracept.
The other option for women with endometriosis who wish to conceive is surgical ablation of deposits of endometriosis. The surgery may be performed laparoscopically including excision, laser or diathermy ablation and adhesiolysis.
A prospective cohort analysis was conducted to analyze results from 579 women with endometriosis to evaluate the role of surgery in the treatment of endometriosis associated with infertility. Adamson GD, Pasta DJ ,1994)
For minimal and mild disease, no treatment, laparoscopy, and laparotomy had equivalent 3-year estimated cumulative life-table pregnancy rates (67% +/- 12%, 68% +/- 4%, and 74% +/- 8%, respectively) that were higher than medical treatment pregnancy rates (p = 0.003).
The authors urged for prospective randomized trials to be performed to confirm these findings.
Marcaux et al, 1997 conducted a randomized controlled trial to reach a clear evidence on ablation of minimal or mild endometriosis. They studied 341 infertile women 20 to 39 years of age with minimal or mild endometriosis.
During diagnostic laparoscopy the women were randomly assigned to undergo resection or ablation of visible endometriosis or diagnostic laparoscopy only. They were followed for 36 weeks after the laparoscopy
Fetal losses occurred in 20.6% of all the recognized pregnancies in the laparoscopic-surgery group and in 21.6% of all those in the diagnostic-laparoscopy group (P=0.91) . The authors concluded that Laparoscopic resection or ablation of minimal and mild endometriosis enhances fecundity in infertile women.
Two years later, a group from Italy have conducted another randomized controlled trial to evaluate the available evidence. Eligible women were randomly assigned to resection or ablation of visible endometriosis (54 patients) or diagnostic laparoscopy only (47 patients).
Two points should be noticed in these two trials. First, in order to be able to conclude that removing endometriosis is effective, then it would be better not to do the adhesiolysis which can be considered as a co-intervention. However, this was not done.
The second point is that the patients were informed about the result of procedure done (ablation or no ablation) immediately after laparoscopy at their postoperative appointments. This could have a possible negative placebo effect on those in expectant group or a positive placebo effect in those who had ablation.
If we consider only late pregnancies in the these two trials (50/172 in the ablation group versus 29/169 in the no surgery group in the Canadian study and 10/54 versus 10/47 respectively in the Italian study), the O.R would be 1.64 (95% CI, 1.02–2.67) noticing that the lower confidence interval limit is too close to unity
If we express the results more practically in terms of number of women to undergo surgery to achieve an additional pregnancy. In this case, even taking into account only the results of the Canadian trial, the benefit of laparoscopic ablation appears less encouraging.
However, considering that we cannot identify women with endometriosis preoperatively, and that the proportion of subjects with endometriosis in the Canadian series of patients undergoing laparoscopy for unexplained infertility was a little <50%, the number needed to be treated doubles at least
Interestingly, the Canadian group has also conducted a well designed prospective cohort study ( 1998) to assess whether infertile women with minimal or mild endometriosis have lower fecundity than women with unexplained infertility.
Infertile women with minimal or mild endometriosis (n = 168) were compared with women with unexplained infertility (n = 263). Both groups were managed expectantly. The women were followed up for 36 weeks after the laparoscopy or, for those who became pregnant, for up to 20 weeks of the pregnancy.
Fecundity was 18.2% in infertile women with minimal or mild endometriosis and 23.7% in women without endometriosis. The fecundity rate was 2.52 per 100 person-months in women with endometriosis and 3.48 per 100 person-months in women with unexplained infertility.
The crude and adjusted fecundity rate ratios were 0.72 and 0.83 (95% confidence interval = 0.53-1.32), respectively. Thus, The fecundity of infertile women with minimal or mild endometriosis is not significantly lower than that of women with unexplained infertility.
Laparoscopic ablation for minimal or mild endometriosis associated subfertility seems to be of very limited efficacy. Exposing those women to unnecessary anaesthesia and laparoscopic manipulations should not be done except in the context of randomized controlled trial
Recommendations (if you decide to do ablation)
Exclude all other causes of subfertility
Estimate the probability of pregancy with and without treatment.