Follicular fluid (FF) constitutes the microenvironment of the developing oocyte. We recently characterized its lipid composition and found lipid signatures of positive pregnancy outcome after in vitro fertilization (IVF). In the current study, we aimed to test the hypothesis that unexplained female infertility is related to lipid metabolism, given the lipid signature of positive-outcome IVF patients we previously found. Assuming that FF samples from IVF patients with male factor infertility can represent a non-hindered metabolic microenvironment, we compared them to FF taken from women with unexplained infertility. FF from patients undergoing IVF was examined for its lipid composition. We found highly increased triacylglycerol levels, with a lower abundance of monoacylglycerols, phospholipids and sphingolipids in the FF of patients with unexplained infertility. The alterations in the lipid class accumulation were independent of the body mass index (BMI) and were altogether kept across the age groups. Potential lipid biomarkers for pregnancy outcomes showed a highly discriminative abundance in the FF of unexplained infertility patients. Lipid abundance distinguished IVF patients with unrecognized infertility and provided a potential means for the evaluation of female fertility.

中文翻译：

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甘油脂代谢的改变定义了无法解释的不育症IVF患者的卵泡液。

卵泡液（FF）构成了发育中的卵母细胞的微环境。我们最近对其脂质成分进行了表征，并在体外受精（IVF）后发现了阳性妊娠结局的脂质特征。在当前的研究中，鉴于我们先前发现的阳性结果IVF患者的脂质特征，我们旨在检验无法解释的女性不育与脂质代谢有关的假设。假设来自IVF男性不育患者的FF样品可以代表无阻碍的代谢微环境，我们将它们与来自无法解释的不育女性的FF进行了比较。检查接受IVF的患者的FF的脂质成分。我们发现三酰甘油水平大大提高，而单酰甘油含量较低，无法解释的不育症患者FF中的磷脂和鞘脂。脂质类别积累的变化与体重指数（BMI）无关，并且在各个年龄段中都保持不变。可能导致妊娠结局的脂质生物标记物在无法解释的不育症患者的FF中显示出很高的判别力。脂质丰度使IVF患者具有无法识别的不育症，并为评估女性生育力提供了潜在手段。