UCD Perinatal Research Centre, UCD School of Medicine, University College Dublin, Dublin, Ireland.
National Maternity Hospital, Dublin 2, Ireland.
Microbiol Spectr. 2024 Nov 5;12(11):e0113024. doi: 10.1128/spectrum.01130-24. Epub 2024 Oct 4.
The vaginal microbiome is a key player in the etiology of spontaneous preterm birth. This study aimed to illustrate maternal environmental factors associated with vaginal microbiota composition and function in pregnancy. Women in healthy pregnancy had vaginal microbial sampling from the posterior vaginal fornix performed at 16 weeks gestation. After shotgun metagenomic sequencing, heatmaps of relative abundance data were generated. Community state type (CST) was assigned, and alpha diversity was calculated. Demography, obstetric history, well-being, exercise, and diet using food frequency questionnaires were collected and compared against microbial parameters. A total of 119 pregnant participants had vaginal metagenomic sequencing performed. Factors with strongest association with beta diversity were dietary lysine (adj- 0.113, = 0.002), valine (adj- 0.096, = 0.004), leucine (adj- 0.086, = 0.003), and phenylalanine (adj- 0.085, = 0.005, Fig. 2D). Previous vaginal delivery and breastfeeding were associated with vaginal beta diversity (adj- 0.048, = 0.003; adj- 0.045, = 0.004), accounting for 8.5% of taxonomy variation on redundancy analysis. Dietary fat, starch, and maltose were positively correlated with alpha diversity (fat +0.002 SD/g, = 0.025; starch +0.002 SD/g, = 0.043; maltose +0.440 SD/g, = 0.013), particularly in secretor-positive women. Functional signature was associated with CST, maternal smoking, and dietary phenylalanine, accounting for 8.9%-11% of the variation in vaginal microbiome functional signature. Dietary amino acids, previous vaginal delivery, and breastfeeding history were associated with vaginal beta diversity. Functional signature of the vaginal microbiome differed with community state type, smoking, dietary phenylalanine, and vitamin K. Increased alpha diversity correlated with dietary fat and starch. These data provide a novel snapshot into the associations between maternal environment, nutrition, and the vaginal microbiome.
This secondary analysis of the MicrobeMom randomized controlled trial reveals that dietary amino acids, macronutrients, previous vaginal birth, and breastfeeding have the strongest associations with vaginal taxonomy in early pregnancy. Function of the vaginal niche is associated mainly by species composition, but smoking, vitamin K, and phenylalanine also play a role. These associations provide an intriguing and novel insight into the association between host factors and diet on the vaginal microbiome in pregnancy and highlight the need for further investigation into the complex interactions between the diet, human gut, and vaginal microbiome.
阴道微生物群是自发性早产病因学中的关键因素。本研究旨在阐明与妊娠期间阴道微生物群组成和功能相关的母体环境因素。健康妊娠的女性在妊娠 16 周时从阴道后穹窿进行阴道微生物采样。进行鸟枪法宏基因组测序后，生成相对丰度数据的热图。分配社区状态类型（CST）并计算 alpha 多样性。使用食物频率问卷收集人口统计学、产科史、健康状况、运动和饮食方面的数据，并与微生物参数进行比较。共有 119 名孕妇进行了阴道宏基因组测序。与 beta 多样性关联最强的因素是膳食赖氨酸（adj-0.113， = 0.002）、缬氨酸（adj-0.096， = 0.004）、亮氨酸（adj-0.086， = 0.003）和苯丙氨酸（adj-0.085， = 0.005，图 2D）。既往阴道分娩和母乳喂养与阴道 beta 多样性相关（adj-0.048， = 0.003；adj-0.045， = 0.004），占冗余分析中分类群变异的 8.5%。膳食脂肪、淀粉和麦芽糖与 alpha 多样性呈正相关（脂肪+0.002 SD/g， = 0.025；淀粉+0.002 SD/g， = 0.043；麦芽糖+0.440 SD/g， = 0.013），尤其是在分泌型阳性女性中。功能特征与 CST、母亲吸烟和膳食苯丙氨酸相关，占阴道微生物组功能特征变异的 8.9%-11%。膳食氨基酸、既往阴道分娩和母乳喂养史与阴道 beta 多样性相关。阴道微生物组的功能特征因 CST、吸烟、膳食苯丙氨酸和维生素 K 而异。增加的 alpha 多样性与膳食脂肪和淀粉相关。这些数据为母体环境、营养与阴道微生物组之间的关联提供了新的认识。
这项对 MicrobeMom 随机对照试验的二次分析表明，妊娠早期，膳食氨基酸、宏量营养素、既往阴道分娩和母乳喂养与阴道分类群关系最密切。阴道生态位的功能主要与物种组成相关，但吸烟、维生素 K 和苯丙氨酸也有作用。这些关联为宿主因素和饮食对妊娠期间阴道微生物组的关联提供了一个有趣且新颖的视角，并强调需要进一步研究饮食、人类肠道和阴道微生物组之间的复杂相互作用。
