Increase in Bifidobacterium is a characteristic of the difference in the salivary microbiota of pregnant and non-pregnant women

Abstract

Background The establishment of symbiotic microbiota in pregnant women is important for both the mother and her offspring. Little is known about the salivary symbiotic bacteria in pregnancy, and analysis of composition of microbiome (ANCOM) is useful to detect small differences in the number of bacteria. The aim of this study was to investigate the differences in the salivary bacteria between healthy pregnant and non-pregnant women using ANCOM. Methods Unstimulated saliva samples were collected from 35 healthy pregnant women at 35 weeks gestation and 30 healthy non-pregnant women during menstruation. All participants underwent a periodontal examination. Estradiol and progesterone levels were examined by enzyme-linked immunosorbent assay. DNA extracted from the saliva was assessed by 16S ribosomal RNA amplicon sequencing and real-time PCR. Results Salivary estradiol and progesterone levels were significantly increased in pregnant women. The alpha and beta diversities were higher in pregnant women than in non-pregnant women. The largest effect size difference noted when the microbiota of the pregnant and non-pregnant women were analyzed was that for Bifidobacteriales. Levels of Bifidobacterium dentium, but not of Bifidobacterium adolescentis, were significantly increased in pregnant women, and the levels were significantly correlated with progesterone concentration. Conclusion The results suggest that Bifidobacterium and progesterone levels are elevated in the saliva of healthy pregnant women compared with non-pregnant women.

Cervical and Vaginal Microbiomes in Early Miscarriages and Ongoing Pregnancy with and without Dydrogesterone Usage

“…According to the research of Kato et al (2022), B. dentium was significantly higher in the saliva of pregnant women than in non-pregnant women. In addition, the abundance of B. dentium in this study significantly correlated with the concentration of progesterone in saliva in all subjects [ 26 ]. In our study, we observed a similar effect in the cervical and vaginal environments, where B. dentium is abundant in the group of patients who are taking dydrogesterone, which is a synthetic progesterone drug.…”

Cryptic Oral Microbiota: What is its Role as OSA-related Periodontal Pathogens?

“…It had also been implicated in obesity and diabetes [81]. Moreover, it had found a substantial correlation between B. dentium abundance and pregnant women's salivary progesterone concentrations [82] and also, pregnant women who had B. dentium had greater levels of IL-6 and IL-8 [83]. The G3 and G4 had the highest frequency of Bifidobacterium sp.…”

Transmission and Persistence of Infant Gut-Associated Bifidobacteria

“…Bifidobacterium suspended in house dust due to aerosolization of fecal material during routine caregiving may be a source of inoculation early in infant gut colonization and potentially a reservoir for reintroduction after microbiome disruption due to infection or antibiotic usage [70,71]. Similarly, Bifidobacterium dentium was found in higher abundance in salivary samples from pregnant women than in menstruating women [72], which potentially serves as an inoculation source for infants during contact and caregiving. Any contributions made by B. dentium to infant gut microbiome function would likely be as an allochthonous member through transient passage.…”