Mandelbaum Rachel, Stanczyk Frank Z
Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, California.
F S Rep. 2024 May 23;5(3):237-247. doi: 10.1016/j.xfre.2024.05.007. eCollection 2024 Sep.
Programmed or medicated frozen embryo transfer cycles rely on exogenous progesterone (P) administration to prepare the endometrium for implantation and maintain pregnancy. Presently, the optimal route and dose of P replacement for frozen embryo transfer are not known. In addition, there is a paucity of data and insufficient understanding regarding the metabolism and actions of P in implantation and pregnancy maintenance. In the present review, we discuss how different P assay methodologies affect the determination of P thresholds for implantation and pregnancy maintenance. In addition, we discuss the importance of free P and its regulation in the endometrium and show the complexity of molecular signaling that is required for P-dependent endometrial receptivity. We concluded that future studies should focus on defining accurate circulating and endometrial P concentrations, both for total and free P, and how these concentrations correlate with endometrial receptivity and clinical outcomes.
程序化或药物性冷冻胚胎移植周期依赖于外源性孕激素（P）给药，以使子宫内膜为着床做好准备并维持妊娠。目前，冷冻胚胎移植中孕激素替代的最佳途径和剂量尚不清楚。此外，关于孕激素在着床和维持妊娠中的代谢及作用的数据匮乏，人们对此了解不足。在本综述中，我们讨论了不同的孕激素检测方法如何影响着床和维持妊娠的孕激素阈值的确定。此外，我们讨论了游离孕激素的重要性及其在内膜中的调节，并展示了孕激素依赖性子宫内膜容受性所需分子信号传导的复杂性。我们得出结论，未来的研究应集中于确定总孕激素和游离孕激素准确的循环及子宫内膜浓度，以及这些浓度如何与子宫内膜容受性和临床结局相关联。
