How does endometrial scratch work?

How Does Endometrial Scratch or Injury Work?

"Endometrial Injury and Hysteroscopy Increase Leukemia Inhibitory Factor Expression: A Preliminary Study"

Reproductive Biology and Endocrinology 2022-20:11

Understanding the Injury Process:

Leukemia inhibitory factor (LIF) is a cytokine that plays a crucial role in successful embryo implantation by regulating cell proliferation, differentiation, and survival in the endometrium. LIF is also involved in embryo-endometrium interactions and injury-induced wound healing.

Low LIF Expression Consequences:

Insufficient endometrial LIF expression may lead to infertility. Disruptions in the LIF pathway are observed in the endometrium of patients with unexplained infertility, particularly in cases of endometriosis and endometrioma.

Study Methodology:

The study aimed to investigate the impact of endometrial injury on LIF gene expression and pregnancy rates in patients undergoing IVF treatment. Two patient groups were included: one underwent endometrial scratching, and the other did not. Hysteroscopy was performed on all participants, and those with endometrial pathology detected during diagnostic hysteroscopy were excluded. Endometrial LIF mRNA expression was found to increase 11 times in the injury group using monopolar cautery and 3.9 times in other cases.

Results Analysis:

The study revealed significantly higher positive pregnancy test rates in the injury group compared to the control group. Clinical pregnancy was observed in 7 cases (35%) in the injury group and 5 cases (25%) in the control group, with a significant difference.

Limitations and Uncertainties:

The primary limitation of using mechanical endometrial injury to enhance pregnancy rates is the absence of clear data on which patient group, when, how often, and with which instruments it should be applied. Although endometrial injury has been reported to increase clinical pregnancy, it does not consistently produce positive results in unselected patient groups.

The exact physiological mechanisms behind the method's success remain unknown, and limited data on the mechanism of action through which injury improves pregnancy rates is also a significant limitation.

Conclusion:

The precise mechanism by which injury enhances pregnancy rates is not well-understood, and current data on endometrial injury are insufficient to recommend routine use of this method. Further studies are required to determine if endometrial injury should be offered to patients to improve pregnancy rates