Effect of endometrial mechanical stimulation in an unselected population undergoing in vitro fertilization: futility analysis of a double-blind randomized controlled trial.

Implantation failure is a major limiting factor of successful in vitro fertilization (IVF). The objective of this study was to determine if endometrial mechanical stimulation (EMS) by endometrial biopsy in the luteal phase of the cycle prior to embryo transfer (ET) improves clinical outcomes in an unselected subfertile population. Double-blind, randomized controlled trial of EMS versus sham biopsy and odds of clinical pregnancy after IVF and embryo transfer. Secondary outcomes included spontaneous miscarriage and live birth. One hundred women enrolled and were randomized from 2013 to 2017. Enrollment was terminated after futility analysis showed no difference in clinical pregnancy between EMS versus control, 47.2% vs 61.7% (OR 0.55, 95% CI 0.25-1.23, p = 0.15). There were no significant differences between women who underwent EMS and those who did not in terms of positive pregnancy test 54.7% vs 63.8% (OR 0.69, 95% CI 0.31-1.53, p = 0.36), miscarriage 7.5% vs 2.1% (OR 3.76 95% CI 0.41-34.85, p = 0.22), or live birth 43.4% vs 61.7% (OR 0.48 95% CI 0.21-1.06, p = 0.07). EMS in the luteal phase of the cycle preceding embryo transfer does not improve clinical outcomes in an unselected subfertile population and may result in a lower live birth rate. We caution the routine use of EMS in an unselected population.