Endometrial scratching in IVF/ICSI treatment: Clinical effectiveness and prognostic factors

Test-tube treatment (IVF/ICSI) is frequently being used to treat infertility worldwide, but unfortunately only 35% of the transferred embryos implant. Endometrial scratching, a procedure in which a biopsy is taken from the lining of the uterus, has been suggested to improve implantation. This thesis describes a review, randomized clinical trial and individual participant data analysis (IPD) that study whether endometrial scratching improves embryo implantation – and thus live birth –, if it is cost-effective, if it is more or less effective in subgroups of women, and if scratching affects pregnancy complications or a low birthweight.
The randomized controlled trial showed that a single scratch in women with one failed IVF/ICSI cycle probably increases the chance of a live birth with approximately 4.6%-point (confidence interval -0.7% - +9.9%). This effect remained after 12 months (5.1%-point increase, confidence interval -1.2% - +11.4%). Cost-effectiveness depends on the exact effect and the costs for a scratch. Based on the Dutch estimations, IVF/ICSI with scratching will cost approximately €17,500.- for each additional live birth, which is below the threshold of €20,000.-. We could not identify subgroups of women that benefit more or less from scratching, and we could not find an association with pregnancy complications or a low birthweight.
The timing of scratching in the menstrual cycle could be essential to the effect on live birth, and could therefore, along with the underlying biological mechanism of action, be a focus for future research.