Therapeutic Efficacy of Endometrial Scratching in Repeated Controlled Ovarian Stimulation (COS) Failure Cycles

The objective of the study was (1) "to evaluate the therapeutic efficacy of endometrial scratching in repeated controlled ovarian stimulation (COS) failure cycles." And (2) "to compare differences in pregnancy outcome by endometrial scratching in early (D2-D4) and late follicular phases (D7-D9) of the same stimulation cycle."

Women attending infertility clinic in a tertiary care center and who have two or more repeated COS failure cycles and planned for COS with intrauterine insemination (IUI) were included in the study which is a prospective parallel, interventional, single-blinded, randomized control study, in 1:1 allocation ratio. A total of 165 patients were recruited and randomly allocated into three groups: Group A (n = 55) underwent endometrial scratching on D2-D4 of the same COS cycle, Group B (n = 55) on D7-D9, and Group C (n = 55) no intervention done. All the patients underwent COS according to standard protocol followed by IUI.

Clinical pregnancy rate was 12.73% (odds ratio [OR] =0.87 95% confidence interval [CI] =0.288-2.55, P = 1), 16.36% (OR = 1.15; 95% CI = 0.40-3.23, P = 1), and 14.54%, respectively, in Group A, B, and C, respectively (P = 0.86), as per intention to treat analysis. Using Chi-square test, P value between Group A and B was 0.787, between Group A and C was 1.000, and between Group B and C was 1.000. As per protocol analysis, clinical pregnancy rate was 13.46% (OR = 0.83; 95% CI = 0.27-2.5, P = 0.74), 19.57% (OR = 1.3 95%; CI = 0.45-3.73, P = 0.41), and 15.69%. Using Chi-square test, Pvalue between Group A and B was 0.588, between Group A and C was 0.967, and between Group B and C was 0.815. No abortions and multiple pregnancies occurred in either of the groups.

The effect found was of good quantum in Group B as per protocol analysis which could be of clinical relevance if larger sample size would have been taken. Endometrial scratching is a cost-effective and easy technique which may improve clinical pregnancy rates in previous COS failure cycles, but more trials are needed to be conducted using larger sample size to achieve the improved and significant outcome.