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Author Spotlight: Advancing Therapeutic Strategies for Improving Pregnancy Rates by Analyzing Embryo-Endometrium Interactions
Published on: June 21, 2024
In Vitro Human Endometrial Cells and In Vivo Rat Model Studies Suggest That Ulipristal Acetate Impacts Endometrial
Pablo Ángel García-Uribe1, Gabriela Hernández-Silva1, Claudia Cecilia Vega1
1Departamento de Biología de la Reproducción Dr. Carlos Gual Castro, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico.
Background:
Ulipristal acetate (UPA) and levonorgestrel are used as emergency hormonal contraceptives. Although both are highly effective in preventing pregnancy, UPA shows efficacy even when taken up to 120 h after unprotected sexual intercourse.
Aims:
To investigate whether the mechanism of UPA's contraceptive action involves post-fertilization effects.
Methods:
In vitro and in vivo studies using cultured human endometrial cells and a pre-clinical rat model.
Results:
Endometrial cells treated with UPA showed changes in the expression of receptivity gene markers and a significant decrease in trophoblast spheroids attached to the cultured cells. In addition, administration of UPA to female unmated rats decreased the expression of implantation-related genes in the endometrium and inhibited the number of implantation sites in the mated group compared to the non-treated group.
Conclusions:
These results support that UPA as an emergency contraceptive might have post-fertilization effects that may affect embryo implantation.

