Department of Obstetrics and Gynecology, Division of Obstetrics and Feto-Maternal Medicine, Medical University of Vienna, and Comprehensive Center for Pediatrics (CCP), Medical University of Vienna, Vienna, Austria.
Joint Microbiome Facility, Medical University of Vienna and University of Vienna, Vienna, Austria.
Acta Obstet Gynecol Scand. 2024 May;103(5):832-841. doi: 10.1111/aogs.14773. Epub 2024 Jan 24.
Changes within the maternal microbiome during the last trimester of pregnancy and the determinants of the subsequent neonatal microbiome establishment after delivery by elective cesarean section are described.
Maternal vaginal and rectal microbiome samples were collected in the last trimester and before cesarean section; intrauterine cavity, placenta, neonatal buccal mucosa, skin, and meconium samples were obtained at birth; neonatal sample collection was repeated 2-3 days postnatally. Microbial community composition was analyzed by 16S rRNA gene amplicon sequencing. Relative abundance measurements of amplicon sequencing variants and sum counts at higher taxonomic levels were compared to test for significant overlap or differences in microbial community compositions.
gov ID: NCT04489056.
A total of 30 mothers and their neonates were included with available microbiome samples for all maternal, intrauterine cavity and placenta samples, as well as for 18 of 30 neonates. The composition of maternal vaginal and rectal microbiomes during the last trimester of healthy pregnancies did not significantly change (permutational multivariate analysis of variance [PERMANOVA], p > 0.05). No robust microbial signature was detected in the intrauterine cavity, placenta, neonatal buccal mucosa, skin swabs, or meconium samples collected at birth. After birth, the neonatal microbiome was rapidly established, and significantly different microbial communities were detectable 2-3 days postnatally in neonate buccal mucosa and stool samples (PERMANOVA, p < 0.01).
Maternal vaginal and rectal microbiomes in healthy pregnancies remain stable during the third trimester. No microbial colonization of the neonate was observed before birth in healthy pregnancies. Neonatal microbiomes in infants delivered by cesarean section displayed a taxonomic composition distinct from maternal vaginal and rectal microbiomes at birth, indicating that postnatal exposure to the extrauterine environment is the driving source of initial neonatal microbiome development in this cohort.
本研究描述了妊娠晚期母体微生物组的变化，以及经择期剖宫产分娩后新生儿微生物组建立的决定因素。
在妊娠晚期和剖宫产前采集母体阴道和直肠微生物组样本；在出生时采集子宫腔、胎盘、新生儿口腔黏膜、皮肤和胎粪样本；在出生后 2-3 天重复采集新生儿样本。通过 16S rRNA 基因扩增子测序分析微生物群落组成。通过比较扩增子测序变体的相对丰度测量值和更高分类水平的总和计数，来检验微生物群落组成是否存在显著重叠或差异。
gov ID：NCT04489056。
共有 30 名母亲及其新生儿纳入研究，所有母亲、子宫腔和胎盘样本均有可用的微生物组样本，其中 30 名新生儿中有 18 名新生儿有可用的样本。健康妊娠晚期母体阴道和直肠微生物组的组成没有显著变化（随机置换多元方差分析[PERMANOVA]，p>0.05）。在出生时采集的子宫腔、胎盘、新生儿口腔黏膜、皮肤拭子或胎粪样本中未检测到稳健的微生物特征。出生后，新生儿微生物组迅速建立，出生后 2-3 天新生儿口腔黏膜和粪便样本中可检测到明显不同的微生物群落（PERMANOVA，p<0.01）。
健康妊娠的母体阴道和直肠微生物组在妊娠晚期保持稳定。在健康妊娠中，在出生前未观察到新生儿的微生物定植。经剖宫产分娩的婴儿的新生儿微生物组在出生时具有与母体阴道和直肠微生物组不同的分类组成，这表明在本队列中，产后暴露于子宫外环境是新生儿初始微生物组发育的驱动源。
