BACKGROUND Obesity has now been recognized as a high-risk factor for reproductive health. Although remarkable advancements have been made in ART, a considerable number of infertile obese women still suffer from serial implantation failure, despite the high quality of embryos transferred. Although obesity has long been known to exert various deleterious effects on female fertility, the underlying mechanisms, especially the roles of lipid metabolism in endometrial receptivity, remain largely elusive. OBJECTIVE AND RATIONALE This review summarizes current evidence on the impacts of several major lipids and lipid-derived mediators on the embryonic implantation process. Emerging methods for evaluating endometrial receptivity, for example transcriptomic and lipidomic analysis, are also discussed. SEARCH METHODS The PubMed and Embase databases were searched using the following keywords: (lipid or fatty acid or prostaglandin or phospholipid or sphingolipid or endocannabinoid or lysophosphatidic acid or cholesterol or progesterone or estrogen or transcriptomic or lipidomic or obesity or dyslipidemia or polycystic ovary syndrome) AND (endometrial receptivity or uterine receptivity or embryo implantation or assisted reproductive technology or in vitro fertilization or embryo transfer). A comprehensive literature search was performed on the roles of lipid-related metabolic pathways in embryo implantation published between January 1970 and March 2022. Only studies with original data and reviews published in English were included in this review. Additional information was obtained from references cited in the articles resulting from the literature search. OUTCOMES Recent studies have shown that a fatty acids-related pro-inflammatory response in the embryo-endometrium boundary facilitates pregnancy via mediation of prostaglandin signaling. Phospholipid-derived mediators, for example endocannabinoids, lysophosphatidic acid and sphingosine-1-phosphate, are associated with endometrial receptivity, embryo spacing and decidualization based on evidence from both animal and human studies. Progesterone and estrogen are two cholesterol-derived steroid hormones that synergistically mediate the structural and functional alterations in the uterus ready for blastocyst implantation. Variations in serum cholesterol profiles throughout the menstrual cycle imply a demand for steroidogenesis at the time of window of implantation (WOI). Since 2002, endometrial transcriptomic analysis has been serving as a diagnostic tool for WOI dating. Numerous genes that govern lipid homeostasis have been identified and, based on specific alterations of lipidomic signatures differentially expressed in WOI, lipidomic analysis of endometrial fluid provides a possibility for non-invasive diagnosis of lipids alterations during the WOI. WIDER IMPLICATIONS Given that lipid metabolic dysregulation potentially plays a role in infertility, a better understanding of lipid metabolism could have significant clinical implications for the diagnosis and treatment of female reproductive disorders.

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脂质代谢与子宫内膜容受性

背景肥胖现在已被认为是生殖健康的高风险因素。尽管 ART 取得了显着进步，但尽管转移的胚胎质量很高，但仍有相当多的不孕肥胖女性遭受连续植入失败的困扰。尽管人们早就知道肥胖会对女性生育能力产生各种有害影响，但其潜在机制，尤其是脂质代谢在子宫内膜容受性中的作用，在很大程度上仍然难以捉摸。目的和基本原理 本综述总结了目前关于几种主要脂质和脂质衍生介质对胚胎着床过程影响的证据。还讨论了用于评估子宫内膜容受性的新兴方法，例如转录组学和脂质组学分析。搜索方法 使用以下关键字搜索 PubMed 和 Embase 数据库：（脂质或脂肪酸或前列腺素或磷脂或鞘脂或内源性大麻素或溶血磷脂酸或胆固醇或黄体酮或雌激素或转录组学或脂质组学或肥胖或血脂异常或多囊卵巢综合征）和（子宫内膜容受性或子宫容受性或胚胎植入或辅助生殖技术或体外受精或胚胎移植）。对 1970 年 1 月至 2022 年 3 月发表的脂质相关代谢途径在胚胎植入中的作用进行了全面的文献检索。本综述仅收录了具有原始数据和英文发表评论的研究。其他信息是从文献检索产生的文章中引用的参考文献中获得的。结果 最近的研究表明，胚胎-子宫内膜边界的脂肪酸相关促炎反应通过前列腺素信号传导促进妊娠。基于动物和人类研究的证据，磷脂衍生介质，例如内源性大麻素、溶血磷脂酸和 1- 磷酸鞘氨醇，与子宫内膜容受性、胚胎间距和蜕膜化有关。黄体酮和雌激素是两种胆固醇衍生的类固醇激素，它们协同调节子宫的结构和功能改变，为囊胚植入做好准备。整个月经周期中血清胆固醇分布的变化意味着在植入窗口 (WOI) 时需要类固醇生成。自 2002 年以来，子宫内膜转录组学分析一直作为 WOI 约会的诊断工具。已经确定了许多控制脂质稳态的基因，并且基于 WOI 中差异表达的脂质组学特征的特定改变，子宫内膜液的脂质组学分析为 WOI 期间脂质改变的非侵入性诊断提供了可能性。更广泛的意义鉴于脂质代谢失调可能在不孕症中发挥作用，更好地了解脂质代谢可能对女性生殖障碍的诊断和治疗具有重要的临床意义。子宫内膜转录组学分析一直作为 WOI 约会的诊断工具。已经确定了许多控制脂质稳态的基因，并且基于 WOI 中差异表达的脂质组学特征的特定改变，子宫内膜液的脂质组学分析为 WOI 期间脂质改变的非侵入性诊断提供了可能性。更广泛的意义鉴于脂质代谢失调可能在不孕症中发挥作用，更好地了解脂质代谢可能对女性生殖障碍的诊断和治疗具有重要的临床意义。子宫内膜转录组学分析一直作为 WOI 约会的诊断工具。已经确定了许多控制脂质稳态的基因，并且基于 WOI 中差异表达的脂质组学特征的特定改变，子宫内膜液的脂质组学分析为 WOI 期间脂质改变的非侵入性诊断提供了可能性。更广泛的意义鉴于脂质代谢失调可能在不孕症中发挥作用，更好地了解脂质代谢可能对女性生殖障碍的诊断和治疗具有重要的临床意义。子宫内膜液的脂质组学分析为 WOI 期间脂质改变的非侵入性诊断提供了可能性。更广泛的意义鉴于脂质代谢失调可能在不孕症中发挥作用，更好地了解脂质代谢可能对女性生殖障碍的诊断和治疗具有重要的临床意义。子宫内膜液的脂质组学分析为 WOI 期间脂质改变的非侵入性诊断提供了可能性。更广泛的意义鉴于脂质代谢失调可能在不孕症中发挥作用，更好地了解脂质代谢可能对女性生殖障碍的诊断和治疗具有重要的临床意义。