Eine relativ aktuelle Analyse in Reproductive Bio Medicine Online, Volume 25, Issue 6, Pages 561-571, December 2012 (vier randomisierte und drei nicht randomisierte Studien mit insgesamt 2062 Patientinnen) konnte zeigen, dass wenn LEI im Vorzyklus vor der geplanten Stimulation durchgeführt wurde, dies zu einer 70% höheren klinischen Schwangerschaftsrate führte im Vergleich zu nicht mit LEI behandelten Patienten.
Hier einige Zitaten aus der Studie:
„Overall, with local injury there are changes initiated within the endometrium, the immune system and gene expression, all leading to improved receptivity and a favourable milieu for implantation. It could be that injury in the preceding cycle is more effective as all these events require time and are governed by the hormones. Intervention close to embryo transfer can potentially disturb the endometrium and have a negative effect.“
Die Autoren stellen aber klar:
„This then raises the clinical question whether there is a role of local endometrial injury in the preceding cycle in all women undergoing IVF or whether it should be limited to women with RIF. The potential benefit of this simple inexpensive procedure could well outweigh the risks of infection and potential of future subfertility. The benefits could be enormous in terms of emotional wellbeing and financial savings. Moreover, what these and related data suggest is that the importance of endometrial receptivity in contributing to IVF pregnancy success is being underestimated. However, there are unanswered questions regarding timing of intervention, phase of cycle when injury should be induced, use of hysteroscopy versus endometrial biopsy, mechanism of action for injury induced with hysteroscopy and benefit of single versus multiple biopsies. There is an urgent need for large, multicentre randomized studies investigating local endometrial injury and pregnancy outcomes in the unexplained RIF and in patients with unexplained subfertility undergoing first IVF cycle. The aforementioned queries need to be addressed and the evidence can be further strengthened by simultaneous molecular and gene expression studies on the endometrium. Until the results of such trials are available, or an expert consortium guideline is proposed, it should not be a blanket policy to induce local endometrial injury for women undergoing first cycle of IVF and perhaps there is a role for this in women with unexplained RIF.“