Follicular-phase endometrial scratching: a truncated randomized controlled trial.

Area of Science:

• Reproductive Medicine
• Infertility Treatment
• Assisted Reproductive Technology (ART)

Background:

• Endometrial injury (scratching) is proposed to enhance endometrial receptivity in ART.
• Its effectiveness remains controversial, particularly for in-cycle injury during follicular phase ovarian stimulation (OS).
• Potential harms and effects in subsequent cycles require further investigation.

Purpose of the Study:

• To investigate whether intentional endometrial injury during the follicular phase of OS increases clinical pregnancy rate (CPR) in ART.
• To evaluate secondary outcomes including live birth rate (LBR) and pregnancy loss rates.
• To assess safety concerns and cumulative reproductive outcomes.

Main Methods:

• A randomized controlled trial (RCT) included 200 women undergoing IVF/ICSI.
• Participants were randomized to undergo pipelle endometrial biopsy during OS (Days 6-8) or serve as controls.
• Primary outcome was CPR; secondary outcomes included LBR, pregnancy loss, pain, bleeding, and cumulative LBR within 6 months.

Main Results:

• The RCT was stopped prematurely due to safety concerns (higher clinical miscarriage rate in the intervention group).
• CPR (44% vs. 40%) and LBR (32% vs. 36%) were not significantly different between groups.
• Clinical miscarriages were significantly higher in the endometrial injury group (25% vs. 8%; P=0.032).

Conclusions:

• Intentional endometrial injury during the follicular phase of OS did not improve CPR and was associated with increased clinical miscarriage rates.
• The study was underpowered due to early termination, limiting definitive conclusions.
• Findings suggest potential harm and warrant caution, supporting existing evidence questioning the benefit of endometrial scratching.