[Effects of gestational diabetes mellitus on gut microbiota of 3-month-old infants: a prospective control study].

OBJECTIVE: To explore the effect of gestational diabetes mellitus on the gut microbiota of their offsprings, the gut microbiota of 3-month-old infants whose mothers diagnosed with and without gestational diabetes mellitus(GDM) was compared. METHODS: Pregnant women and their 3-month-old infants who were examined, delivered and follow-up visited in a county in Hebei Province from June 2016 to December 2019 were included in our study. The pregnants and their infants with result of fasting venous blood glucose≥5.1 mmol/L in the second or third trimester were included in GDM group. Fecal samples of 3-month-old infants were collected and 16 S rDNA high-throughput sequencing technology was used to explore the change of gut microbiota. RESULTS: A total of 48 pairs of subjects were included, 16 in GDM group and 32 in control group. Comparison of gut microbiota diversity: analysis of the Alpha diversity index showed that the Observed Species index, margalef index and menhinick index of GDM group were(141.4±17.2), (13.66±1.66) and(0.83±0.10), respectively, which were significantly lower than that of control group(154.9±21.7), (15.00±2.11) and(0.91±0.13), respectively. Sequence analysis: at phylum level, the abundance of the Firmicutes, Bacteroidetes, Actinobacteria and Proteobacteria were 54.28(47.84), 23.58(23.48), 11.20(30.99) and 0.12(0.07), respectively, while the control group were 42.05(36.23), 29.64(21.30), 9.31(15.82) and 0.15(10.14), respectively. The two groups were mainly composed of these 4 phyla and Actinobacteria was the most abundant. At genus level, there were mainly Bifidobacteria, lactobacillus, Enterobacteria, Bacteroidales and Clostridiales in both groups. The abundance of Erysipelotrichales in GDM group(0.01(0.01)) was significantly lower than that in control group(0.04(0.06))(P<0.05). The abundance of Micrococcales in GDM group(0.13(0.24) was significantly lower than that in control group(0.29(0.78))(P<0.05). PCoA analysis showed that the gut microbiota structure of GDM group and control group was similar. LEfSe analysis showed Erysipelatoclostridium was significantly increased in control group(P<0.05). CONCLUSION: GDM can reduce the diversity and richness of gut microbiota of 3-month-old infants and has no significant effect on the phylum level but has effect on some genus level. It suggests that GDM may still have some potential effect on slightly elder infants.

[Effect of pregnant serum folate concentration on newborn's birth weight].

OBJECTIVE: To study the effect of pregnant serum folate concentrations on the birth weight. METHODS: This study was a prospective cohort study. Pregnant women aged 18-45 who were examined and delivered in a county in Hebei Province from June 2016 to August 2018 and their newborns were included in the study. A total of 490 women were recruited and collected venous blood before the 20 th week of pregnancy. Basic information of women as well as their use of folic acid supplements was collected at the same time. Newborns' basic information, such as sex and birth weight, had been collected after delivery. The chemiluminescence method was used to determine the serum folate concentrations. Folate concentrations quartile were used as the cut-off point to divide subjects into four groups. The general linear model and multivariate unconditional Logistic regression analysis were used to study the effect of different serum folate concentrations on the infant birthweight. RESULTS: The age of 490 pregnant women was(27. 9±4. 1) years. The serum folate value P50(P25, P75) was 12. 3(9. 0, 14. 5) ng/mL and its' detection time was(13. 7±2. 6) weeks. 49. 3%(242/490) newborns were male. The average gestational age of the newborns was(39. 1±1. 0) weeks and the average birth weight was(3403±425) g. The birth weight of four groups' newborns were(3408±456) g, (3405±450) g, (3427±418) g and(3374±378) g, respectively. General linear model analysis showed that there was no significant difference in the effect of serum folate levels before the 20 th week of gestation on the birth weight(serum folate concentration<9. 0 ng/mL(ß=32. 24, P=0. 55), serum folate concentration 9. 0-12. 2(ß=18. 01, P=0. 74), serum folate concentration 12. 3-14. 4(ß=42. 27, P=0. 43)]. Multivariate unconditional Logistic regression analysis showed that the group with folate concentration above 14. 5 ng/mL can reduce the risk of small for gestational age(SGA) [(P=0. 02, OR=0. 08(95% CI 0. 01-0. 61)]. Comparing with ghe pregnant women whose serum folate concentration was in 9. 0-12. 4 ng/mL. Hovever, there was no significant difference between the pregnant serum folate levels and large for gestational age(LGA). CONCLUSION: There was no significant correlation between serum folate concentrations and the birth weight. But higher folate level may reduce the risk of SGA.