Characteristics of Gut Microbiota in Small for Gestational Age Infants with Very Low Birth Weight

Abstract

Small for gestational age (SGA) birth is associated with high rates of mortality and morbidity in preterm infants. The aim of this preliminary observational study was to investigate the difference in gut microbiota between SGA and appropriate for gestational age (AGA) preterm infants with very low birth weight (VLBW). We included 20 VLBW preterm infants (SGA, n = 10; AGA, n = 10) in this study. Stool samples were collected on days 7, 14, and 30 after birth. We performed 16S ribosomal DNA sequencing to compare microbiota composition between both groups. The SGA group exhibited a lower abundance of Klebsiella on day 14 (SGA, 0.57%; AGA, 7.42%; p = 0.037). On day 30, the SGA group exhibited a lower abundance of Klebsiella (SGA 3.76% vs. AGA 16.05%; p = 0.07) and Enterobacter (SGA 5.09% vs. AGA 27.25%; p = 0.011) than the AGA group. Beta diversity demonstrated a separation of the bacterial community structure between both groups on day 30 (p = 0.019). The present study revealed that a distinct gut microbiota profile gradually develops in SGA preterm infants with VLBW during the early days of life. The role of changes in gut microbiota structure warrants further investigation.

Carbohydrate-Mediated Pregnancy Gut Microbiota and Neonatal Low Birth Weight

“…Maternal gut microbiota composition and metabolic activity differ before and during pregnancy [24,25]. Numerous studies have suggested associations between the compositions of maternal [26] and/or infant [27,28] gut microbiota and adverse fetal outcomes in many populations. For example, Ruminococcaceae, Lachnospiraceae, and Eubacteriaceae families identified from maternal fecal samples during pregnancy were important predictors of neonatal birth weight and weight at 1 month; Ruminococcaceae, Lachnospiraceae, Eubacteriaceae families, Prevotella copri, and Slackia isoflavoniconvertents were associated with gestational age in the rural Zimbabwe cohort [26].…”

Intestinal flora and linear growth in children

“…Furthermore, stressors associated with neonatal life in the hospital, such as frequent antibiotic usage, invasive procedures, and maternal separation, can all lead to dysbiosis ( 40 ). A small cohort study discovered that SGA newborns had smaller abundances of Klebsiella and Enterobacter than AGA infants, and the Beta diversity of bacterial community structure began to segregate at postnatal day 30 ( 41 ). Transcriptome investigations of the SGA rat model revealed that IGF-2 expression was considerably reduced in CUG (catch-up growth)-SGA rats, which was associated with a decrease in lactic acid bacteria ( 42 ).…”

“…In summary, the maternal microbiota is directly linked to the health of the baby, and its disruption can result in fetal growth and development abnormalities such as premature birth, SGA newborns, and macrosomia. Genetic variables ( 20 ), nutrition before and during pregnancy ( 30 ), manner of birth ( 36 ), and gestational age at birth ( 41 ) all influence baby microbiome colonization. Lactobacillus and Bifidobacterium have been shown to promote fetal growth, but pathogenic bacteria such as Shigella , Ralstonia , and Clostridium have been found to inhibit baby growth ( 29 , 39 ).…”

“…The microbiome of newborns born via cesarean section is mostly derived from the mother's skin and the hospital environment ( 85 ). The most important factors influencing prenatal growth and development are prenatal weight gain ( 28 – 30 ), premature birth ( 31 , 38 , 39 ), and being small for gestational age ( 41 , 44 ). According to research, these elements are linked to the creation and features of newborn gut flora.…”

“…They have complicated interactions with each other. This review mostly includes cohort studies ( 26 , 28 , 30 , 39 , 41 , 44 , 45 , 48 , 53 , 54 , 56 , 59 ), cross-sectional studies ( 31 , 37 , 46 , 51 , 71 , 76 , 78 ), case-control studies ( 29 , 47 , 55 , 57 , 62 ), and some animal studies focusing on particular mechanisms ( 48 , 87 , 88 ). Although the data supports a link between intestinal flora and linear development in children, our review has limitations that prohibit us from fully verifying the causal relationship between gut flora and linear development in children.…”