Maternal gut microbiome and its impact on developing idiopathic late fetal growth retardation

Aim: to analyze a rectal microbiome composition in pregnant women and assess its potential impact on developing of idiopathic late fetal growth retardation (FGR) syndrome. Materials and Methods. We analyzed a course of pregnancy and labour in 80 pregnant women: main group consisted of 40 pregnant women with FGR, control group – of 40 healthy pregnant women. The analysis of the intestinal microbiota in 53 pregnant women (25 pregnant women with late FGR and 28 healthy pregnant women) was carried out by using nitrogenous base sequencing in the 16S ribosomal RNA (rRNA) genes. Results. Analyses of the gut microbiome composition in pregnant women in study groups revealed significant differences particularly showing a 1.0 % increase in the proportion of Clostridiales Ruminococcaceae Oscillospira that correlated with a 331.7 g increase in neonatal weight gain; a 1.0 % increase in the level of Coriobacteriales Coriobacteriaceae Collinsella was associated with a 476.2 g decrease in neonatal weight gain. The Firmicutes/Bacteroides ratio was 2,0 and 3.6 in main and control group (p = 0.02), respectively, which may suggest about a microbiological dysbiosis with putative pathophysiological outcomes. A significant association between elevated leucocyte counts (in the absence of other manifestations of inflammatory processes) and the probability of FGR development was found. A white blood cell count ≥ 11.05×10 9 /L predicted the risk of FGR with a sensitivity of 60.6 % and a specificity of 79.2 %. Also, erythrocyte sedimentation rate level of ≥ 41.5 mm/hour was associated with increased FGR risk, demonstrating a sensitivity of 85.7 % and specificity of 70.6 %. Conclusion. It can be concluded that gut dysbiosis may play a role in development of late idiopathic FGR. A negative correlation between a decreased Firmicutes/Bacteroides ratio as well as higher Actinobacteria proportion and fetal birth weight was found.