RESUMO
Microbiota in pregnant time is vital to healthy of pregnant women and their offspring. However, few study evaluate the composition of the microbiota of health pregnancy, placenta and their newborns at different stages and the origin of the placental microbiota. Samples were obtained from a total of 31 pregnant individuals and their offspring, analyzing by 16S rRNA amplicon sequencing of the V4 region to evaluate the composition and variation of them. We found that the microbiota of pregnant individuals changes in the third trimester. The placental microbiota has its own specific dominant microbiota. The placental microbiota is correlated with the pregnancy microbiota in the gut and vagina at 32-34 weeks but not at full term. The gut microbiota in newborns changes over the first 14 days.
RESUMO
BACKGROUND: The influence of different delivery modes on the mother-to-child transmission (MTCT) rate of pregnant women with high hepatitis B viremia was investigated. METHODS: A retrospective analysis was performed on data for 855 hepatitis- B -virus (HBV) carrier mothers who received regular prenatal care and delivered at the First Affiliated Hospital of Jinan University from January 2011 to October 2015. The neonates were classified into three groups according to the delivery mode: eutocia (438 cases), Non-parturient cesarean delivery (371 cases), and parturient cesarean delivery (46 cases). The neonatal HBV surface antigen (HBsAg) positive rates of the three delivery groups were comparatively analyzed to determine the influence of the delivery mode on HBV MTCT. Of the 855 HBV-carrier mothers, 480 mothers and respective newborns were tested for HBV-DNA and classified into four groups: HBV DNA≥107 copies/mL (96 cases), 105≤HBV DNA<107 copies/mL (37 cases), 103≤HBV DNA<105 copies/mL (85 cases), and HBV DNA<103 copies/mL (262 cases). The effect of the HBV DNA titers of these pregnant women on HBV MTCT was analyzed. RESULTS: Statistically significant (P<0.05) differences were found among the HBsAg positive rates of neonates of HBV-carrier pregnant women delivered by the three methods from HBV-carrier pregnant women with HBV DNA≥107 copies/mL. No statistically significant (P>0.05) differences among the HBsAg positive rates were found for neonates delivered by the three methods from HBV-carrier pregnant women with HBV DNA<107 copies/mL. CONCLUSIONS: The delivery mode may influence the risk of HBV maternal-to-infant vertical transmission for HBV-carrier pregnant women with HBV DNA≥107 copies/mL. That is, elective cesarean section may reduce the HBV maternal-to-infant vertical transmission.
