The environment for embryo implantation and fetal growth and development is affected by maternal nutritional, metabolic and health status. The aim of this prospective, cohort study was to test whether plasma metabolic and inflammatory biomarkers can predict pregnancy resulting from in vitro fertilisation (IVF). Women with a natural menstrual cycle undergoing frozen embryo transfer (FET) were recruited and fasting baseline blood samples were collected a mean of 3.4 days prior to the luteinising hormone (LH) surge and a non-fasting blood sample was taken on the day of FET. Ongoing pregnancy was defined by positive fetal heartbeat on ultrasound scan at day 45 post LH surge. Thirty-six pregnancies resulted from FET in 143 women. In an overall stepwise multivariable analysis, erythrocyte saturated to unsaturated fatty acid ratio was positively associated with ongoing pregnancy. A similar model incorporating day of FET covariates found that erythrocyte saturated to unsaturated fatty acid ratio, erythrocyte fatty acid average chain length and plasma log-triglycerides predicted ongoing pregnancy. In conclusion, a higher peri-conceptional saturated to unsaturated fatty acid ratio predicted ongoing pregnancy after natural cycle frozen embryo transfer and may reflect a maternal nutritional status that facilitates pregnancy success in this assisted conception scenario.

中文翻译：

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孕前孕妇的红细胞饱和脂肪酸与不饱和脂肪酸的比率预示着自然周期冷冻胚胎移植后的怀孕。

孕产妇的营养，代谢和健康状况会影响胚胎植入和胎儿生长发育的环境。这项前瞻性队列研究的目的是测试血浆代谢和炎症生物标记物是否可以预测体外受精（IVF）所致的妊娠。招募经过冷冻胚胎移植（FET）的自然月经周期的妇女，并在黄体激素（LH）激增之前平均3.4天收集空腹基线血液样本，并在FET当天采集非空腹血液样本。持续妊娠的定义是LH激增后第45天在超声扫描中发现胎儿的心跳为阳性。FET在143名妇女中导致了36例怀孕。在整体逐步多变量分析中，红细胞饱和脂肪酸与不饱和脂肪酸的比例与持续妊娠呈正相关。包含一天FET协变量的类似模型发现，红细胞饱和与不饱和脂肪酸之比，红细胞脂肪酸平均链长和血浆对数甘油三酸酯可预测持续妊娠。总之，较高的围孕期饱和脂肪酸与不饱和脂肪酸之比预示着自然周期冷冻胚胎移植后的持续妊娠，并且可能反映出在此辅助受孕情况下有利于妊娠成功的孕产妇营养状况。