Characteristics of the gut microbiome in women with gestational diabetes mellitus:A systematic review

BACKGROUND: The incidence of women developing gestational diabetes mellitus (GDM) is increasing, which is associated with an increased risk of type 2 diabetes mellitus (T2DM) for both mother and child. Gut microbiota dysbiosis may contribute to the pathogenesis of both GDM and the accompanying risk of T2DM. Thus, a better understanding of the microbial communities associated with GDM could offer a potential target for intervention and treatment in the future. Therefore, we performed a systematic review to investigate if the GDM women have a distinct gut microbiota composition compared to non-GDM women. METHODS: We identified 21 studies in a systematic literature search of Embase and PubMed up to February 24, 2021. Data on demographics, methodology and identified microbial metrics were extracted. The quality of each study was assessed according to the Newcastle-Ottawa Scale. RESULTS: Sixteen of the studies did find a GDM-associated gut microbiota, although no consistency could be seen. Only Collinsella and Blautia showed a tendency to be increased in GDM women, whereas the remaining genera were significantly different in opposing directions. CONCLUSION: Although most of the studies found an association between GDM and gut microbiota dysbiosis, no overall GDM-specific gut microbiota could be identified. All studies in the second trimester found a difference between GDM and non-GDM women, indicating that dysbiosis is present at the time of diagnosis. Nevertheless, it is still unclear when the dysbiosis develops, as no consensus could be seen between the studies investigating the gut microbiota in the first trimester of pregnancy. However, studies varied widely concerning methodology and study design, which might explain the highly heterogeneous gut microbiota compositions between studies. Therefore, future studies need to include multiple time points and consider possible confounding factors such as ethnicity, pre-pregnancy body mass index, and GDM treatment

Animal Models of Fetal Medicine and Obstetrics

Animal models remain essential to understand the fundamental mechanisms occurring in fetal medicine and obstetric diseases, such as intrauterine growth restriction, preeclampsia and gestational diabetes. These vary regarding the employed method used for induction of the disease, and differ in relation to the animal characteristics (size, number of fetuses, placenta barrier type, etc.). While none of these exactly mirrors the human condition, different pregnant animal models (mice, rats, guinea pigs, chinchillas, rabbits, sheep and pigs) are here described with respect to advantages and limitations. The ability to employ noninvasively diagnostics varies among species, specifically for ultrasound and clinical magnetic resonance imaging procedures. Management of feeding, handling, care and anesthesia are particularly important factors in the pregnant animal

Cycling reduces blood glucose excursions after an oral glucose tolerance test in pregnant women: a randomized crossover trial

The aim of this study was to evaluate the effect of an acute bout of cycling immediately after oral glucose intake on glucose metabolism in pregnant women at risk for gestational diabetes mellitus (GDM). Fifteen pregnant women with BMI ≥ 27 kg/m2 were enrolled in a randomized crossover controlled study and underwent two oral glucose tolerance tests (OGTTs) ingesting 75 g of glucose followed by either 20 min of stationary cycling at moderate intensity (65%–75% maximal heart rate) or rest. Using continuous glucose monitors, glucose was measured up to 48 h after the OGTT. Glucose, insulin, and C-peptide were determined at baseline and after 1 and 2 h. One hour after glucose intake, mean blood glucose was significantly lower after cycling compared with rest (p = 0.002). Similarly, mean glucose peak level was significantly lower after cycling compared with after rest (p = 0.039). Lower levels of insulin and C-peptide were observed after 1 h (p < 0.01). Differences in glucose measurements after 2 h and up to 48 h were not statistically different. We found that 20 min of cycling at moderate intensity after glucose intake reduced blood glucose excursions in pregnant women at risk for GDM. ClinicalTrials.gov Identifier: NCT03644238. Novelty Bullets • In pregnant women, we found that cycling after glucose intake resulted in significantly lower glucose levels compared with rest. • The exercise intervention studied is feasible for pregnant women and could be readily used to reduce glucose excursions.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Diet and Healthy Lifestyle in the Management of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) among pregnant women increases the risk of both short-term and long-term complications, such as birth complications, babies large for gestational age (LGA), and type 2 diabetes in both mother and offspring. Lifestyle changes are essential in the management of GDM. In this review, we seek to provide an overview of the lifestyle changes which can be recommended in the management of GDM. The diet recommended for women with GDM should contain sufficient macronutrients and micronutrients to support the growth of the foetus and, at the same time, limit postprandial glucose excursions and encourage appropriate maternal gestational weight gain. Blood glucose excursions and hyperglycaemic episodes depend on carbohydrate-intake. Therefore, nutritional counselling should focus on the type, amount, and distribution of carbohydrates in the diet. Further, physical activity has beneficial effects on glucose and insulin levels and it can contribute to a better glycaemic control

Temporal Trends in Gestational Diabetes Prevalence, Treatment, and Outcomes at Aarhus University Hospital, Skejby, between 2004 and 2016

Background. The prevalence of gestational diabetes (GDM) is increasing worldwide. The most important risk of GDM in pregnancy is excessive fetal growth, increasing the risk of complications during delivery as well as long-term complications like obesity and diabetes in both the mother and the offspring. Method. All women with GDM who delivered a singleton between 2004 and 2016 were included. The treatment of GDM patients sought to achieve normal blood glucose levels, primarily by diet and exercise. If the glycemic targets were not reached, insulin therapy was initiated. Birth weight and birth weight Z-score was calculated corrected for gender and gestational age at delivery. Results. The study included 1910 women. The number of GDM women increased significantly each year over the course of the study, as did the proportion requiring insulin therapy. Birth weight and birth weight Z-score fell significantly over the years largely due to a decrease in large for gestational age frequency from 29% to around 19%. Conclusion. During the last 13 years, the number of women diagnosed with GDM has increased. Furthermore, the proportion of GDM women receiving insulin treatment has increased. The birth weight in diet-treated women has been virtually normal for the last 5 years of the reported period