Endometrial injury is a simple, low-cost procedure which can be performed on an outpatient basis.
More than 300 publications can be found on this topic, but only four RCTs with poor quality were analyzed in three meta-analyses published in the same year. Interestingly, all of them conclude that endometrial scratching prior to starting IVF treatment may improve the chance of embryo implantation and IVF success rate, although this simple intervention would benefit from well-conducted randomized trials.
Although current evidence suggests some benefit of endometrial injury, we need evidence from well-designed trials that avoid instrumentation of the uterus in the preceding three months, do not cause endometrial damage in the control group, stratify the results for women with and without recurrent implantation failure (RIF) and report live birth.
Its benefit in women with repeated COS failure cycles or couples trying to conceive with IUI and OI remain unclear. If endometrial injury improves reproductive outcomes in this situation, it could provide a low-cost treatment alternative for some couples before they consider undergoing IVF. Studies have shown a slight increase in pregnancy outcome in women with repeated COS failures undergoing endometrial scratching in late follicular phase, but the result was not statistically significant. Larger and adequately powered studies are needed to elucidate the effects of endometrial scratching on the outcome of repeated failed COS cycles.
This intervention must not be advertised as an established practice to improve implantation until real good data demonstrate that it does and biological plausibility is demonstrated.