The gut microbiota contributes to the regulation of glucose metabolism in pregnancy. Abundance of the genus Collinsella is positively correlated with circulating insulin; however, it is unclear what determines Collinsella abundance. This study aims to validate the correlation between Collinsella and insulin and to elucidate if macronutrient intake alters Collinsella abundance and gut microbiota composition. Gut microbiota profiles were assessed by 16S rRNA sequencing in 57 overweight and 73 obese pregnant women from the SPRING (Study of PRobiotics IN Gestational diabetes) trial at 16 weeks gestation and correlated with metabolic hormone levels and macronutrient intake. Gut microbiota composition in the top and bottom 10% of dietary fiber intake was evaluated through network analysis. Collinsella abundance correlated positively with circulating insulin (rho = 0.30, p = 0.0006), independent of maternal BMI, but negatively with dietary fiber intake (rho = -0.20, p = 0.025) in this cohort. Low dietary fiber intake was associated with a gut microbiota favoring lactate fermentation while high fiber intake promotes short-chain fatty acid-producing bacteria. Low dietary fiber may enable overgrowth of Collinsella and alter the overall fermentation pattern in gut microbiota. This suggests that dietary choices during pregnancy can modify the nutritional ecology of the gut microbiota, with potential deleterious effects on the metabolic and inflammatory health of the host. ANZCTR 12611001208998, registered 23/11/2011.

Background: The Theoretical Domains Framework (TDF) is an integrative framework developed from a synthesis of psychological theories as a vehicle to help apply theoretical approaches to interventions aimed at behavior change. Purpose: This study explores experiences of TDF use by professionals from multiple disciplines across diverse clinical settings. Methods: Mixed methods were used to examine experiences, attitudes, and perspectives of health professionals in using the TDF in health care implementation projects. Individual interviews were conducted with ten health care professionals from six disciplines who used the TDF in implementation projects. Deductive content and thematic analysis were used. Results: Three main themes and associated subthemes were identified including: 1) reasons for use of the TDF (increased confidence, broader perspective, and theoretical underpinnings); 2) challenges using the TDF (time and resources, operationalization of the TDF) and; 3) future use of the TDF. Conclusion: The TDF provided a useful, flexible framework for a diverse group of health professionals working across different clinical settings for the assessment of barriers and targeting resources to influence behavior change for implementation projects. The development of practical tools and training or support is likely to aid the utility of TDF.

OBJECTIVE Given the role of gut microbiota in regulating metabolism, probiotics administered during pregnancy might prevent gestational diabetes mellitus (GDM). This question has not previously been studied in high-risk overweight and obese pregnant women. We aimed to determine whether probiotics (Lactobacillus rhamnosus and Bifidobacterium animalis subspecies lactis [BB-12]) administered from the second trimester in overweight and obese women prevent GDM as assessed by an oral glucose tolerance test (OGTT) at 28 weeks’ gestation. Secondary outcomes included maternal and neonatal complications, maternal blood pressure and BMI, and infant body composition. RESEARCH DESIGN AND METHODS This was a double-blind randomized controlled trial of probiotic versus placebo in overweight and obese pregnant women in Brisbane, Australia. RESULTS The study was completed in 411 women. GDM occurred in 12.3% (25 of 204) in the placebo arm and 18.4% (38 of 207) in the probiotics arm (P = 0.10). At OGTT, mean fasting glucose was higher in women randomized to probiotics (79.3 mg/dL) compared with placebo (77.5 mg/dL) (P = 0.049). One- and two-hour glucose measures were similar. Preeclampsia occurred in 9.2% of women randomized to probiotics compared with 4.9% in the placebo arm (P = 0.09). Excessive weight gain occurred in 32.5% of women in the probiotics arm (55 of 169) compared with 46% in the placebo arm (81 of 176) (P = 0.01). Rates of small for gestational age (<10th percentile) were 2.4% in the probiotics arm (5 of 205) and 6.5% in the placebo arm (13 of 199) (P = 0.042). There were no differences in other secondary outcomes. CONCLUSIONS The probiotics used in this study did not prevent GDM in overweight and obese pregnant women.

The composition of the gut microbiota can be influenced by dietary composition. In pregnancy, the maternal gut microbiome has associations with maternal and infant metabolic status. There is little known regarding the impact of a vegetarian diet in pregnancy on maternal gut microbiota. This study explored the gut microbiota profile in women who were vegetarian or omnivorous in early gestation. Women were selected from participants in the Study of PRobiotics IN Gestational diabetes (SPRING) randomised controlled trial. Nine women identified as vegetarians were matched to omnivorous women in a 1:2 ratio. Microbiota analyses were performed using 16S rRNA gene amplicon sequencing and analysed using the Quantitative Insights Into Microbial Ecology (QIIME) and Calypso software tools. There was no difference in alpha diversity, but beta diversity was slightly reduced in vegetarians. There were differences seen in the relative abundance of several genera in those on a vegetarian diet, specifically a reduction in Collinsella, Holdemania, and increases in the relative abundances of Roseburia and Lachnospiraceae. In this sub-analysis of gut microbiota from women in early pregnancy, a vegetarian as compared to omnivorous diet, was associated with a different gut microbiome, with features suggesting alterations in fermentation end products from a mixed acid fermentation towards more acetate/butyrate.