Overweight and the metabolic syndrome in adult offspring of women with diet-treated gestational diabetes mellitus or type 1 diabetes

Genetics and epigenetics in gestational diabetes contributing to type 2 diabetes

Gestational diabetes mellitus (GDM) is a common pregnancy complication and a risk factor for the subsequent development of type 2 diabetes (T2D) in mothers and of several metabolic diseases in offspring. However, the molecular underpinnings of these risks are not well understood. Genome-wide association studies (GWAS) and epigenetic studies may provide complementary insights into the causal relationships between GDM exposure and maternal/offspring metabolic outcomes. In this review we discuss the potential pathophysiological roles of specific genetic variants and commonly reported differentially methylated loci in GDM development, and their link to the progression to T2D in both the mother and the offspring in later life, pointing to the potential for tailored interventional strategies based on these genetic and epigenetic mechanisms.

Comparison of universal screening for gestational diabetes mellitus between one-step and two-step method among Thai pregnant women: A randomized control trial

AIMS

To compare the prevalence of GDM and pregnancy outcomes between the one-step and two-step methods of universal screening among Thai pregnant women.

METHODS

A randomized controlled trial was conducted on singleton Thai pregnant women at a gestational age of 24-28 weeks. They were randomly assigned to either the one-step method group (a universal 75-gm 2-h oral glucose tolerance test: OGTT) or the two-step method group (a universal 50-gm oral glucose challenge test followed by a 100-gm 3-h OGTT). The women received standard antenatal care. The prevalence of GDM and obstetric outcomes were compared.

RESULTS

A total of 143 women meeting the inclusion criteria were randomly allocated into the one-step group (72 cases) and the two-step group (71 cases). The prevalence of GDM was significantly higher in the one-step group than in the two-step group, with rates of 24/73 (33.3%) vs 8/70 (11.3%); P value 0.002; relative risk of 2.96, 95% CI: 1.43-6.14, respectively. Demographic data and maternal and neonatal outcomes were comparable between the two groups.

CONCLUSIONS

The one-step method can markedly increase the prevalence of GDM to nearly three times that of the two-step method, leading to a substantial increase in care costs and burdens without clear benefits. Convincingly, the one-step method as a new approach may not be suitable for universal screening in a busy antenatal care setting, especially in low-resource health centers in developing countries or among populations with a high prevalence of GDM.

Early-life exposure to gestational diabetes mellitus predisposes offspring to pediatric nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) has emerged as the prevailing chronic liver disease in the pediatric population due to the global obesity pandemic. Evidence shows that prenatal and postnatal exposure to maternal abnormalities leads to a higher risk of pediatric NAFLD through persistent alterations in developmental programming. Gestational diabetes mellitus (GDM) is a hyperglycemic syndrome which has become the most prevalent complication in pregnant women. An increasing number of both epidemiologic investigations and animal model studies have validated adverse and long-term outcomes in offspring following GDM exposure in utero. Similarly, GDM is considered a crucial risk factor for pediatric NAFLD. This review aimed to summarize currently published studies concerning the inductive roles of GDM in offspring NAFLD development during childhood and adolescence. Dysregulations in hepatic lipid metabolism and gut microbiota in offspring, as well as dysfunctions in the placenta are potential factors in the pathogenesis of GDM-associated pediatric NAFLD. In addition, potentially effective interventions for GDM-associated offspring NAFLD are also discussed in this review. However, most of these therapeutic approaches still require further clinical research for validation.

Maternal Diabetes and Cardiovascular Health in the Offspring

Pulse wave velocity (PWV) has been explored to predict cardiovascular health in adults. Less is known about neonatal PWV. We evaluated the association between arterial stiffness of neonates of mothers (NoM) with diabetes and childhood health. Neonatal brachial-femoral PWV (bfPWV) was measured after birth and neonates followed for a median of 5.2 years [1 month-6.6 years]. 36 pregnant women with pregestational diabetes mellitus PGDM (n = 12), gestational diabetes mellitus (GDM) (n = 13), and controls (n = 11) were enrolled. Neonates were similar in weight, gestational age, and delivery mode. 26 neonates had follow-up data including weight, height and blood pressure. More mothers with PGDM had poor glycemic control compared to mothers with GDM (83% vs. 8%; p = 0.0002). PWV was higher in NoM with PGDM than controls (3.4 ± 0.5 vs. 2.6 ± 0.8 m/s; p = 0.04). At follow-up, children of mothers with diabetes (n = 16) had higher weight percentile (78.5 ± 27.9 vs 49.5 ± 34.6%; p = 0.02) and diastolic blood pressure (DBP) (68 ± 13.6 vs 57.3 ± 4.3 mmHg; p = 0.01) than controls (n = 10). No correlation emerged between neonatal PWV and childhood body mass index (BMI) or maternal HbA1c. Results suggest maternal diabetes affect neonatal arterial stiffness and childhood blood pressure; however, the mechanism is unclear. The long-term implications of these findings warrant further investigation.

Prediction of gestational diabetes mellitus using early-pregnancy data: a secondary analysis from a prospective cohort study in Iran

BACKGROUND

Early identification of gestational diabetes mellitus is essential for improving maternal and neonatal outcomes. While risk factors such as advanced maternal age, elevated pre-pregnancy body mass index, multiparity, and a history of gestational diabetes have been recognized, the role of serum biomarkers remains uncertain. This study explores the predictive value of early-pregnancy laboratory findings in conjunction with maternal demographic and clinical characteristics for gestational diabetes mellitus.

METHODS

Early-pregnancy data from the first pregnancy visits at 6-12 weeks of gestation from women in the Mothers and Children's Health cohort were collected. Comprehensive maternal demographic data (e.g., age and body mass index) and obstetrics history (e.g., gravidity, parity, miscarriage, intrauterine growth retardation, gestational diabetes mellitus, and preeclampsia) were recorded. Maternal blood samples were analyzed for complete blood count and biochemistry parameters. Gestational diabetes mellitus was diagnosed based on 75-g oral glucose tolerance test results between 24 and 28 weeks of gestation, following the International Association of Diabetes and Pregnancy Study Groups criteria. Multivariate logistic regression analysis assessed the predictive capacity of various variables. Receiver operating curve analysis was conducted to identify optimal predictive cut-offs for continuous variables.

RESULTS

1,565 pregnant women with a mean age of 32.6 ± 5.7 years, mean body mass index of 25.5 ± 4.9 kg/m², mean gravidity of 1.1 ± 1.1, and mean parity of 0.8 ± 0.8 were included. 297 pregnancies (19.0%) were complicated by gestational diabetes mellitus. In the multivariate analysis, higher maternal age (p < 0.001, odds ratio = 1.076 [1.035-1.118]), a history of gestational diabetes mellitus (p < 0.001, odds ratio = 3.007 [1.787-5.060]) and preeclampsia (p = 0.007, odds ratio = 2.710 [1.310-5.604]), and elevated early-pregnancy fasting blood sugar (p < 0.001, odds ratio = 1.062 [1.042-1.083]) emerged as independent predictors of gestational diabetes mellitus. Moreover, the receiver operating curve yielded an optimal cut-off of 89.5 mg/dL for early-pregnancy fasting blood sugar in predicting gestational diabetes mellitus.

CONCLUSIONS

Our findings demonstrated that, in addition to established risk factors, a history of preeclampsia and elevated early-pregnancy fasting blood glucose are independent predictors of gestational diabetes mellitus. Therefore, close monitoring of pregnant women with these risk factors in early pregnancy is warranted to facilitate timely diagnostic and therapeutic interventions, reducing the burden of gestational diabetes.

TRIAL REGISTRATION

Not applicable.

Monocyte-to-lymphocyte ratio in the early second trimester is a predictor of gestational diabetes mellitus

OBJECTIVE

To evaluate neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), neutrophil-to-monocyte ratio (NMR), and other hemogram-derived inflammatory parameters measured in the early second trimester and their association with the risk of gestational diabetes mellitus (GDM).

METHODS

This case-control study was conducted with 105 women with GDM and 205 healthy pregnant women, matched for maternal age at a 1:2 ratio with the cases at two regional maternity hospitals between January 2021 and August 2022. The inflammatory blood cell indices were tested in the early second trimester, and the patient's characteristics and the course of the pregnancy were analyzed. Logistic regression was used to determine the association between hematological parameters and the risk of GDM. Data were analyzed using SPSS, version 25.0 (SPSS, Chicago, IL).

RESULTS

The final analysis included 310 pregnant women. The GDM group showed a higher pre-pregnancy BMI compared to the healthy controls (p < .01). There was no difference in NMR, PLR, and NLR between the groups (p = .63, .54, and .39, respectively). GDM was only positively associated with MLR (p = .02). After adjusting for potential confounding risk factors including maternal age, parity, and BMI, the multivariate regression analysis showed a higher level of MLR, with a cutoff point of 0.312, was independently associated with the risk of GDM (OR = 2.15, 95%CI 1.51-4.31, p = .03). However, ROC analysis showed that the AUC value of MLR was poor (0.670).

CONCLUSIONS

We found that MLR, an inflammatory combined index derived from whole blood counts, may potentially serve as a predictor of GDM in the early second trimester.

Increased purchases of prescription medicines in offspring of women with type 1 diabetes: a Finnish register-based cohort study between 1995 and 2018

OBJECTIVE

This study aimed to assess whether in utero exposure to hyperglycemia influences prescription medicine purchases in the offspring of women with type 1 diabetes (exposed offspring).

PATIENTS/MATERIALS AND METHODS

We identified all singleton exposed offspring born in the hospital district of Helsinki and Uusimaa, Finland, between 1988 and 2011 from the Finnish Medical Birth Register, maintained by the Finnish Institute for Health and Welfare. For each exposed offspring, we obtained five age- and province-matched offspring of women without diabetes (reference offspring), from the Finnish Medical Birth Register. By combining data from three national registers, this longitudinal cohort study assessed prescription medicine purchases in exposed offspring (n = 1,725) and reference offspring (n = 8,755) from seven to thirty years of age. Prescription medicine purchases were grouped according to the Anatomical Therapeutic Chemical (ATC) classification system.

RESULTS

Between 1995 and 2018, a total of 211,490 prescription medicines were purchased. After a median follow-up of 10.9 (interquartile range 4.9,17.6) years, we observed higher incidence risk ratios (IRR) of prescription medicine purchases for several ATC main groups in exposed offspring compared to reference offspring, with the highest IRR of 4.06 (95% CI: 2.78 to 5.94) for medicines affecting metabolism (e.g. diabetes medicines).

CONCLUSION

Our findings suggest that exposed offspring purchase more reimbursable prescription medicines than reference offspring from age seven to thirty years. More research is needed to examine the effects of intrauterine exposure to hyperglycemia on long-term health in offspring.

Maternal Glycemic Status and Longitudinal Fetal Body Composition and Organ Volumes Based on Three-Dimensional Ultrasonography

OBJECTIVE

Gestational diabetes mellitus (GDM) increases the risk of fetal overgrowth as measured by two-dimensional ultrasonography. Whether fetal three-dimensional (3D) soft tissue and organ volumes provide additional insight into fetal overgrowth is unknown.

RESEARCH DESIGN AND METHODS

We prospectively evaluated longitudinal 3D fetal body composition and organ volumes in a diverse U.S. singleton pregnancy cohort (2015-2019). Women were diagnosed with GDM, impaired glucose tolerance (IGT), or normal glucose tolerance (NGT). Up to five 3D ultrasound scans measured fetal body composition and organ volumes; trajectories were modeled using linear mixed models. Overall and weekly mean differences in fetal 3D trajectories were tested across glycemic status, adjusted for covariates.

RESULTS

In this sample (n = 2,427), 5.2% of women had GDM, and 3.0% had IGT. Fetuses of women who developed GDM compared with NGT had larger fractional arm and fractional fat arm volumes from 26 to 35 weeks, smaller fractional lean arm volume from 17 to 22 weeks, and larger abdominal area from 24 to 40 weeks. Fetuses of women with IGT had similar growth patterns, which manifested later in gestation and with larger magnitudes, and had larger fractional lean arm volume. No overall differences were observed among thigh or organ volumes across glycemic status.

CONCLUSIONS

Body composition differed in fetuses of GDM-complicated pregnancies, including larger arm and abdominal measures across the second and third trimesters. Patterns were similar in IGT-complicated pregnancies except that they occurred later in gestation and with larger magnitudes. Future research should explore how lifestyle and medication may alter fetal fat accumulation trajectories among hyperglycemic pregnancies.

Development and Testing of a Mobile App for Management of Gestational Diabetes in Nepal: Protocol for a User-Centered Design Study and Exploratory Randomized Controlled Trial

BACKGROUND

The prevalence of gestational diabetes mellitus (GDM) is increasing, particularly in low- and middle-income countries (LMICs) like Nepal. GDM self-management, including intensive dietary and lifestyle modifications and blood glucose monitoring, is critical to maintain glycemic control and prevent adverse outcomes. However, in resource-limited settings, several barriers hinder optimal self-management. Mobile health (mHealth) technology holds promise as a strategy to augment GDM treatment by promoting healthy behaviors and supporting self-management, but this approach has not yet been tested in any LMIC.

OBJECTIVE

This report describes the protocol to develop a culturally tailored mHealth app that supports self-management and treatment of GDM (GDM-Dhulikhel Hospital [GDM-DH] app, phase 1) and test its usability and preliminary efficacy (phase 2) among patients with GDM in a periurban hospital setting in Nepal.

METHODS

The study will be conducted at Dhulikhel Hospital in Dhulikhel, Nepal. In the development phase (phase 1), a prototype of the GDM-DH app will be developed based on expert reviews and a user-centered design approach. To understand facilitators and barriers to GDM self-management and to gather feedback on the prototype, focus groups and in-depth interviews will be conducted with patients with GDM (n=12), health care providers (n=5), and family members (n=3), with plans to recruit further if saturation is not achieved. Feedback will be used to build a minimum viable product, which will undergo user testing with 18 patients with GDM using a think-aloud protocol. The final GDM-DH app will be developed based on user feedback and following an iterative product design and user testing process. In the randomized controlled trial phase (phase 2), newly diagnosed patients with GDM (n=120) will be recruited and randomized to either standard care alone or standard care plus the GDM-DH app from 24-30 weeks gestation until delivery. In this proof-of-concept trial, feasibility outcomes will be app usage, self-monitoring adherence, and app usability and acceptability. Exploratory treatment outcomes will be maternal glycemic control at 6 weeks post partum, birth weight, and rates of labor induction and cesarean delivery. Qualitative data obtained from phase 1 will be analyzed using thematic analysis. In phase 2, independent 2-tailed t tests or chi-square analyses will examine differences in outcomes between the 2 treatment conditions.

RESULTS

As of July 2024, we have completed phase 1. Phase 2 is underway. The first participant was enrolled in October 2021, with 99 participants enrolled as of July 2024. We anticipate completing recruitment by December 2024 and disseminating findings by December 2025.

CONCLUSIONS

App-based lifestyle interventions for GDM management are not common in LMICs, where GDM prevalence is rapidly increasing. This proof-of-concept trial will provide valuable insights into the potential of leveraging mHealth app-based platforms for GDM self-management in LMICs.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04198857; https://clinicaltrials.gov/study/NCT04198857.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/59423.

Biochemical Markers in the Prediction of Pregnancy Outcome in Gestational Diabetes Mellitus

Background and Objectives: Gestational diabetes mellitus (GDM) may impact both maternal and fetal/neonatal health. The identification of prognostic indicators for GDM may improve risk assessment and selection of patient for intensive monitoring. The aim of this study was to find potential predictors of adverse pregnancy outcome in GDM and normoglycemic patients by comparing the levels of different biochemical parameters and the values of blood cell count (BCC) between GDM and normoglycemic patients and between patients with adverse and good outcome. Materials and Methods: Prospective clinical study included 49 patients with GDM (study group) and 44 healthy pregnant women (control group) who underwent oral glucose tolerance test (OGTT) at gestational age of 24-28 weeks. At the time of OGTT peripheral blood was taken for the determination of glucose levels, insulin, glycated hemoglobin, lipid status, homeostatic model assessment, BCC, iron and zinc metabolism, liver function, kidney function and inflammatory status. Each group was divided into two subgroups-normal and poor pregnancy outcome. Results: Higher RBC, hemoglobin concentration, hematocrit value, fasting glucose, uric acid and fibrinogen were found in GDM patients compared to control group. In GDM patients with poor pregnancy outcome values of fibrinogen, ALT, sedimentation rate, granulocyte and total leukocyte counts were elevated, while the serum level of zinc was significantly lower. Higher level of fibrinogen was found in normoglycemic patients with adverse pregnancy outcomes. ROC curve was constructed in order to assess fibrinogen's biomarker potential. The established AUC value for diagnostic ROC was 0.816 (p < 0.001, 95% CI 0.691-0.941), while the AUC value for assessing fibrinogen's potential to predict poor pregnancy outcome in GDM was 0.751 (p = 0.0096, 95% CI 0.561-0.941). Conclusions: The results of our study demonstrated that the best prognostic potential in GDM showed inflammation related parameters, identifying fibrinogen as a parameter with both diagnostic and prognostic ability.

Gestational diabetes in twin pregnancies-a pathology requiring treatment or a benign physiological adaptation?

There is level-1 evidence that screening for and treating gestational diabetes in singleton pregnancies reduce maternal and neonatal morbidity. However, similar data for gestational diabetes in twin pregnancies are currently lacking. Consequently, the current approach for the diagnosis and management of gestational diabetes in twin pregnancies is based on the same diagnostic criteria and glycemic targets used in singleton pregnancies. However, twin pregnancies have unique physiological characteristics, and many of the typical gestational diabetes-related complications are less relevant for twin pregnancies. These differences raise the question of whether the greater increase in insulin resistance observed in twin pregnancies (which is often diagnosed as diet-treated gestational diabetes) should be considered physiological and potentially beneficial in which case alternative criteria should be used for the diagnosis of gestational diabetes in twin pregnancies. In this review, we summarize the most up-to-date evidence on the epidemiology, pathophysiology, and clinical consequences of gestational diabetes in twin pregnancies and review the available data on twin-specific screening and diagnostic criteria for gestational diabetes. Although twin pregnancies are associated with a higher incidence of diet-treated gestational diabetes, diet-treated gestational diabetes in twin pregnancies is less likely to be associated with adverse outcomes and accelerated fetal growth than in singleton pregnancies and may reduce the risk for intrauterine growth restriction. In addition, there is currently no evidence that treatment of diet-treated gestational diabetes in twin pregnancies improves outcomes, whereas preliminary data suggest that strict glycemic control in such cases might increase the risk for intrauterine growth restriction. Overall, these findings provide support to the hypothesis that the greater transient increase in insulin resistance observed in twin pregnancies is merely a physiological exaggeration of the normal increase in insulin resistance observed in singleton pregnancies (that is meant to support 2 fetuses) rather than a pathology that requires treatment. These data illustrate the need to develop twin-specific screening and diagnostic criteria for gestational diabetes to avoid overdiagnosis of gestational diabetes and to reduce the risks associated with overtreatment of diet-treated gestational diabetes in twin pregnancies. Although data on twin-specific screening and diagnostic criteria are presently scarce, preliminary data suggest that the optimal screening and diagnostic criteria in twin pregnancies are higher than those currently used in singleton pregnancies.

Circular RNA hsa_circ_0002268 (PHACTR1) Is Specific to Gestational Diabetes Mellitus in a Polish Pregnant Population

Gestational diabetes mellitus (GDM) is an intolerance of carbohydrate of any degree, which appears for the first time or is diagnosed during pregnancy. The objective of this study is to assess the differences in circular RNA (circRNA) in a Polish pregnant population with and without GDM. A total of 62 pregnant women, 34 with GDM and 28 controls, were enrolled in the study. Total RNAs were extracted from plasma and reverse transcription to complementary DNA (cDNA) was performed. A panel covering 271 amplicons, targeting both linear and circular as well as negative control gene transcripts, was used. Next-generation sequencing was used to evaluate the circRNA quantity. Data analysis was performed using the Coverage Analysis plugin in the Torrent Suite Software (Torrent Suite 5.12.3). A two-step normalization was performed by dividing each transcript read count by the total number of reads generated for the sample, followed by dividing the quantity of each transcript by β-actin gene expression. Both circular and linear forms of RNAs were independently evaluated. A total of 57 transcripts were dysregulated between pregnant women with GDM and controls. Most of the targets (n = 25) were downregulated (cut-off ratio below 0.5), and one target showed a trend toward strong upregulation (ratio 1.45). A total of 39 targets were positively correlated with fasting plasma glucose (FPG), but none of the tested targets were correlated with insulin, CRP or HOMA-IR levels. Among the pregnant women with gestational diabetes, the relative quantity of hsa_circ_0002268 (PHACTR1) was approximately 120% higher than among healthy pregnant women: 0.046 [0.022-0.096] vs. 0.021 [0.007-0.047], respectively, (p = 0.0029). Elevated levels of hsa_circ_0002268 (PHACTR1) might be specific to the Polish population of pregnant women with GDM, making it useful as a potential molecular biomarker in the management of GDM in Poland.

Gestational diabetes mellitus and development of intergenerational non-alcoholic fatty liver disease (NAFLD) after delivery: a systematic review and meta-analysis

Background

It is known that gestational diabetes mellitus (GDM)-complicated pregnancies could affect maternal cardiometabolic health after delivery, resulting in hepatic dysfunction and a heightened risk of developing non-alcoholic fatty liver disease (NAFLD). Hence, this study aims to summarise existing literature on the impact of GDM on NAFLD in mothers and investigate the intergenerational impact on NAFLD in offspring.

Methods

Using 4 databases (PubMed, Embase, Web of Science and Scopus) between January 1980 and December 2023, randomized controlled trials and observational studies that assessed the effect of maternal GDM on intergenerational liver outcomes were extracted and analysed using random-effects meta-analysis to investigate the effect of GDM on NAFLD in mothers and offspring. Pooled odds ratio (OR) was calculated using hazards ratio (HR), relative risk (RR), or OR reported from each study, with corresponding 95% confidence intervals (CI), and statistical heterogeneity was assessed with the Cochran Q-test and I2 statistic, with two-sided p values. The study protocol was pre-registered on PROSPERO (CRD42023392428).

Findings

Twenty studies pertaining to mothers and offspring met the inclusion criteria and 12 papers were included further for meta-analysis on intergenerational NAFLD development. Compared with mothers without a history of GDM, mothers with a history of GDM had a 50% increased risk of developing NAFLD (OR 1.50; 95% CI: 1.21-1.87, over a follow-up period of 16 months-25 years. Similarly, compared with offspring born to non-GDM-complicated pregnancies, offspring born to GDM-complicated pregnancies displayed an approximately two-fold elevated risk of NAFLD development (2.14; 1.57-2.92), over a follow-up period of 1-17.8 years.

Interpretation

This systematic review and meta-analysis suggests that both mothers and offspring from GDM-complicated pregnancies exhibit a greater risk to develop NAFLD. These findings underline the importance of early monitoring of liver function and prompt intervention of NAFLD in both generations from GDM-complicated pregnancies.

Funding

No funding was available for this research.

Maternal birth weight as an indicator of early and late gestational diabetes mellitus: The Japan Environment and Children's Study

AIMS

This study aimed to investigate the association of maternal birth weight (MBW) with early and late gestational diabetes mellitus (GDM).

METHODS

A total of 69318 pregnant Japanese women were included in this birth cohort study. The associations between maternal birth weight and early gestational diabetes mellitus (diagnosed at <24 gestational weeks) and late GDM (diagnosed at ≥24 gestational weeks) were investigated using a multinomial logistic regression model, with an maternal birth weight of 3000-3499 g as the reference category.

RESULTS

Lower maternal birth weight was associated with higher odds of developing early and late gestational diabetes mellitus (P < 0.0001 and P < 0.0001, respectively). The adjusted odds ratios (aORs) for early gestational diabetes mellitus in participants with a MBW of <2500 g and 2500-2999 g were 1.345 (95% confidence interval [CI]: 0.912-1.984) and 1.338 (95% CI: 1.098-1.629), respectively. The aORs for late gestational diabetes mellitus in participants with a MBW of <2500 g and 2500-2999 g were, 1.657 (95% CI: 1.298-2.115) and 1.218 (95% CI: 1.058-1.402), respectively.

CONCLUSIONS

Regardless of the gestational age when gestational diabetes mellitus was diagnosed, a lower maternal birth weight was associated with an increased risk of gestational diabetes mellitus. Furthermore, the association of a MBW <2500 g with late gestational diabetes mellitus tended to be stronger than that with early gestational diabetes mellitus.

Danish Diabetes Birth Registry 2: a study protocol of a national prospective cohort study to monitor outcomes of pregnancies of women with pre-existing diabetes

INTRODUCTION

Despite technological developments and intensified care, pregnancies in women with pre-existing diabetes are still considered high-risk pregnancies. The rate of adverse outcomes in pregnancies affected by diabetes in Denmark is currently unknown, and there is a limited understanding of mechanisms contributing to this elevated risk. To address these gaps, the Danish Diabetes Birth Registry 2 (DDBR2) was established. The aims of this registry are to evaluate maternal and fetal-neonatal outcomes based on 5 years cohort data, and to identify pathophysiology and risk factors associated with short-term and long-term outcomes of pregnancies in women with pre-existing diabetes.

METHODS AND ANALYSIS

The DDBR2 registry is a nationwide 5-year prospective cohort with an inclusion period from February 2023 to February 2028 of pregnancies in women with all types of pre-existing diabetes and includes registry, clinical and questionnaire data and biological samples of mother-partner-child trios. Eligible families (parents age ≥18 years and sufficient proficiency in Danish or English) can participate by either (1) basic level data obtained from medical records (mother and child) and questionnaires (partner) or (2) basic level data and additional data which includes questionnaires (mother and partner) and blood samples (all). The primary maternal outcome is Hemoglobin A1c (HbA1c) levels at the end of pregnancy and the primary offspring endpoint is the birth weight SD score. The DDBR2 registry will be complemented by genetic, epigenetic and metabolomic data as well as a biobank for future research, and the cohort will be followed through data from national databases to illuminate possible mechanisms that link maternal diabetes and other parental factors to a possible increased risk of adverse long-term child outcomes.

ETHICS AND DISSEMINATION

Approval from the Ethical Committee is obtained (S-20220039). Findings will be sought published in international scientific journals and shared among the participating hospitals and policymakers.

TRIAL REGISTRATION NUMBER

NCT05678543.

Diabetes Mellitus and Pregnancy: An Insight into the Effects on the Epigenome

Worldwide, diabetes mellitus represents a growing health problem. If it occurs during pregnancy, it can increase the risk of various abnormalities in early and advanced life stages of exposed individuals due to fetal programming occurring in utero. Studies have determined that maternal conditions interfere with the genotypes and phenotypes of offspring. Researchers are now uncovering the mechanisms by which epigenetic alterations caused by diabetes affect the expression of genes and, therefore, the development of various diseases. Among the numerous possible epigenetic changes in this regard, the most studied to date are DNA methylation and hydroxymethylation, as well as histone acetylation and methylation. This review article addresses critical findings in epigenetic studies involving diabetes mellitus, including variations reported in the expression of specific genes and their transgenerational effects.

Association of Placental Tissue Metabolite Levels with Gestational Diabetes Mellitus: a Metabolomics Study

The purpose of the study is to investigate the metabolic characteristics of placental tissue in patients diagnosed with gestational diabetes mellitus (GDM). Ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS) was employed to qualitatively and quantitatively analyze the metabolites in placental tissues obtained from 25 healthy pregnant women and 25 pregnant women diagnosed with GDM. Multilevel statistical methods are applied to process intricate metabolomics data. Meanwhile, we applied machine learning techniques to identify biomarkers that could potentially predict the risk of long-term complications in patients with GDM as well as their offspring. We identified 1902 annotated metabolites, out of which 212 metabolites exhibited significant differences in GDM placentas. In addition, the study identifies a set of risk biomarkers that effectively predict the likelihood of long-term complications in both pregnant women with GDM and their offspring. The accuracy of this panel was measured by the area under the receiver operating characteristic curve (ROC), which was found to be 0.992 and 0.960 in the training and validation sets, respectively. This study enhances our understanding of GDM pathogenesis through metabolomics. Furthermore, the panel of risk markers identified could prove to be a valuable tool in predicting potential long-term complications for both GDM patients and their offspring.

Gestational Diabetes Mellitus and Metabolic Syndrome: A Review of the Associations and Recommendations

OBJECTIVE

Gestational diabetes mellitus (GDM) and metabolic syndrome (MetS) share common characteristics and risk factors. Both conditions increase the risk of chronic diseases and, thus, may share a common pathogenesis. This review begins with a clinical vignette, followed by evidence supporting the risk of MetS after GDM among women and their offspring and the risk of having GDM among pregnant women who have MetS before pregnancy.

METHODS

Research studies published between 2010 and 2023 were identified via several databases, including PubMed, the Web of Science, MEDLINE, Science Direct, ERIC, and EBSCOhost. Search terms included gestational diabetes and metabolic syndrome. Reviews, books/e-books, patents, news, trade publications, reports, dissertations/theses, conference materials, and articles in non-English languages were all excluded.

RESULTS

MetS increases not only the incidence of GDM during pregnancy but also the risk of diabetes in women with a history of GDM. On the other hand, women with a history of GDM had an almost 4 times increased risk of developing MetS at minimum of 1 year after delivery, and the risk increases with longer time lapse since the index pregnancy. Prepregnancy body mass index appears to be the strongest factor predicting MetS. Children exposed to GDM in utero have at least a 2 times increased risk of MetS in later life.

CONCLUSION

Timely assessment and continuing surveillance of MetS before and after pregnancy followed by GDM are recommended. Weight management and nutrition counseling are of importance to reduce the risk of GDM and MetS among pregnant women.

Epigenetic Network in Immunometabolic Disease

Although a large amount of data consistently shows that genes affect immunometabolic characteristics and outcomes, epigenetic mechanisms are also heavily implicated. Epigenetic changes, including DNA methylation, histone modification, and noncoding RNA, determine gene activity by altering the accessibility of chromatin to transcription factors. Various factors influence these alterations, including genetics, lifestyle, and environmental cues. Moreover, acquired epigenetic signals can be transmitted across generations, thus contributing to early disease traits in the offspring. A closer investigation is critical in this aspect as it can help to understand the underlying molecular mechanisms further and gain insights into potential therapeutic targets for preventing and treating diseases arising from immuno-metabolic dysregulation. In this review, the role of chromatin alterations in the transcriptional modulation of genes involved in insulin resistance, systemic inflammation, macrophage polarization, endothelial dysfunction, metabolic cardiomyopathy, and nonalcoholic fatty liver disease (NAFLD), is discussed. An overview of emerging chromatin-modifying drugs and the importance of the individual epigenetic profile for personalized therapeutic approaches in patients with immuno-metabolic disorders is also presented.

Inflammation and Oxidative Stress Induced by Obesity, Gestational Diabetes, and Preeclampsia in Pregnancy: Role of High-Density Lipoproteins as Vectors for Bioactive Compounds

Inflammation and oxidative stress are essential components in a myriad of pathogenic entities that lead to metabolic and chronic diseases. Moreover, inflammation in its different phases is necessary for the initiation and maintenance of a healthy pregnancy. Therefore, an equilibrium between a necessary/pathologic level of inflammation and oxidative stress during pregnancy is needed to avoid disease development. High-density lipoproteins (HDL) are important for a healthy pregnancy and a good neonatal outcome. Their role in fetal development during challenging situations is vital for maintaining the equilibrium. However, in certain conditions, such as obesity, diabetes, and other cardiovascular diseases, it has been observed that HDL loses its protective properties, becoming dysfunctional. Bioactive compounds have been widely studied as mediators of inflammation and oxidative stress in different diseases, but their mechanisms of action are still unknown. Nonetheless, these agents, which are obtained from functional foods, increase the concentration of HDL, TRC, and antioxidant activity. Therefore, this review first summarizes several mechanisms of HDL participation in the equilibrium between inflammation and oxidative stress. Second, it gives an insight into how HDL may act as a vector for bioactive compounds. Third, it describes the relationships between the inflammation process in pregnancy and HDL activity. Consequently, different databases were used, including MEDLINE, PubMed, and Scopus, where scientific articles published in the English language up to 2023 were identified.

Exposure to Gestational Diabetes and BMI Trajectories Through Adolescence: The Exploring Perinatal Outcomes Among Children Study

CONTEXT

Previous studies have shown that exposure to maternal gestational diabetes mellitus (GDM) is associated with increased offspring body mass index (BMI) and risk for overweight or obesity.

OBJECTIVE

This study aimed to explore differences in BMI trajectories among youth exposed or not exposed to maternal GDM and understand whether these associations differ across life stages.

METHODS

Data from 403 mother/child dyads (76 exposed; 327 not exposed) participating in the longitudinal Exploring Perinatal Outcomes among Children (EPOCH) study in Colorado were used. Participants who had 2 or more longitudinal height measurements from 27 months to a maximum of 19 years were included in the analysis. Life stages were defined using puberty related timepoints: early childhood (27 months to pre-adolescent dip [PAD, average age 5.5 years]), middle childhood (from PAD to age at peak height velocity [APHV, average age 12.2 years]), and adolescence (from APHV to 19 years). Separate general linear mixed models, stratified by life stage, were used to assess associations between GDM exposure and offspring BMI.

RESULTS

There was not a significant association between exposure to GDM and BMI trajectories during early childhood (P = .27). In middle childhood, participants exposed to GDM had higher BMI trajectories compared to those not exposed (males: P = .005, females: P = .002) and adolescent (P = .02) periods.

CONCLUSION

Our study indicates that children who are exposed to GDM may experience higher BMI trajectories during middle childhood and adolescence, but not during early childhood. These data suggest that efforts to prevent childhood obesity among those exposed in utero to maternal GDM should start before pubertal onset.

Metal Exposure during Early Pregnancy and Risk of Gestational Diabetes Mellitus: Mixture Effect and Mediation by Phospholipid Fatty Acids

Despite existing studies exploring the association between metal exposure and gestational diabetes mellitus (GDM), most of them have focused on a single metal or a small mixture of metals. Our prospective work investigated the joint and independent effects of early gestational exposure to 17 essential and nonessential metals on the GDM risk and potential mediation by plasma phospholipid fatty acids (PLFAs) based on a nested case-control study established with 335 GDM cases and 670 randomly matched healthy controls. The Bayesian kernel machine regression (BKMR) and quantile g-computation analyses demonstrated a joint effect from metal co-exposure on GDM risk. BKMR with hierarchical variable selection indicated that the group of essential metals was more strongly associated with GDM than the group of nonessential metals with group posterior inclusion probabilities (PIPs) of 0.979 and 0.672, respectively. Cu (0.988) and Ga (0.570) had the largest conditional PIPs within each group. We also observed significant mediation effects of selected unsaturated PLFAs on Cu-GDM and Ga-GDM associations. KEGG enrichment analysis further revealed significant enrichment in the biosynthesis of unsaturated PLFAs. C18:1 n-7 exhibited the largest proportion of mediation in both associations (23.8 and 22.9%). Collectively, our work demonstrated the joint effect of early gestational metal exposure on GDM risk and identified Cu and Ga as the key species to the joint effect. The findings lay a solid ground for further validation through multicenter investigations and mechanism exploration via laboratory studies.

Low birthweight is associated with a higher incidence of type 2 diabetes over two decades independent of adult BMI and genetic predisposition

AIMS/HYPOTHESIS

Low birthweight is a risk factor for type 2 diabetes. Most previous studies are based on cross-sectional prevalence data, not designed to study the timing of onset of type 2 diabetes in relation to birthweight. We aimed to examine associations of birthweight with age-specific incidence rate of type 2 diabetes in middle-aged to older adults over two decades.

METHODS

Adults aged 30-60 years enrolled in the Danish Inter99 cohort in 1999-2001 (baseline examination), with information on birthweight from original birth records from 1939-1971 and without diabetes at baseline, were eligible. Birth records were linked with individual-level data on age at diabetes diagnosis and key covariates. Incidence rates of type 2 diabetes as a function of age, sex and birthweight were modelled using Poisson regression, adjusting for prematurity status at birth, parity, polygenic scores for birthweight and type 2 diabetes, maternal and paternal diabetes history, socioeconomic status and adult BMI.

RESULTS

In 4590 participants there were 492 incident type 2 diabetes cases during a mean follow-up of 19 years. Type 2 diabetes incidence rate increased with age, was higher in male participants, and decreased with increasing birthweight (incidence rate ratio [95% CI per 1 kg increase in birthweight] 0.60 [0.48, 0.75]). The inverse association of birthweight with type 2 diabetes incidence was statistically significant across all models and in sensitivity analysis.

CONCLUSIONS/INTERPRETATION

A lower birthweight was associated with increased risk of developing type 2 diabetes independent of adult BMI and genetic risk of type 2 diabetes and birthweight.

GAP (gestational diabetes and pharmacotherapy) - study protocol for a randomized controlled, two-arm, single-site trial

BACKGROUND

Gestational diabetes (GDM) complicates 10% of pregnancies in the US. First-line treatment is medical nutrition therapy (MNT) and exercise. Second line is pharmacotherapy. The definition of what constitutes an unsuccessful trial of MNT and exercise has not been established. Tight glycemic control has been demonstrated to reduce GDM-related neonatal and maternal clinical complications. However, it could also increase rates of small-for-gestational age and carry negative effects on patient-reported outcomes such as anxiety and stress. We will study the effect of earlier and stricter pharmacotherapy in GDM on clinical and patient-reported outcomes.

METHODS

GDM and pharmacotherapy (GAP) study is a two-arm parallel, pragmatic randomized controlled trial, where 416 participants with GDM are randomized 1:1 to: 1) Intervention group - insulin initiation at 20% elevated glucose values on a weekly glucose log following MNT and exercise trial and insulin titration to keep elevated glucose values <20%; or 2) Active control group - insulin initiation at 40% elevated glucose values on a weekly log following MNT and exercise and insulin titration to keep elevated glucose values <40%. The primary outcome is a composite neonatal outcome of large-for-gestational-age, macrosomia, birth trauma, preterm birth, hypoglycemia, and hyperbilirubinemia. Secondary outcomes include preeclampsia, cesarean birth, small-for-gestational-age, maternal hypoglycemia, and patient-reported outcomes of anxiety, depression, perceived stress, and diabetes self-efficacy.

CONCLUSIONS

The GAP study will investigate the optimal glycemic threshold for pharmacotherapy addition to MNT and exercise in GDM. The GAP study will promote standardization in GDM management and will have direct relevance for clinical practice.

The Incidence and Management of Type 2 Diabetes Mellitus After Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) refers to a transient state of impaired glucose tolerance that develops during pregnancy, affecting a significant proportion of expectant mothers globally. This review aimed to comprehensively examine the subsequent incidence and management of type 2 diabetes mellitus (T2DM) in women who have previously experienced GDM. The transition from GDM to T2DM is a well-recognized continuum, with affected women facing an increased risk of developing T2DM postpartum. Several studies have demonstrated that women with a history of GDM face a substantially higher risk of developing T2DM compared to normoglycemic pregnant women. The long-term consequences of developing T2DM following GDM are significant, as it not only affects the health of the mother but also poses risks to the offspring. The most common risk factors associated with the progression of GDM to T2DM include pregnancy at an advanced age, insulin treatment during pregnancy, and delivering an overweight baby. As GDM women are at higher risk of developing T2DM, effective management strategies such as lifestyle changes, postpartum care, breastfeeding, screening tests, and gaining awareness of risk are crucial to mitigate the risk of T2DM in this population. The current review was conducted to guide healthcare providers and women with a history of GDM about the potential risks of T2DM and management strategies to prevent the condition. This review provides a summary of evidence on the incidence rate of T2DM in GDM patients, its associated risk factors, and approaches to mitigate this challenge.

The Effect of Gestational Diabetes Mellitus on Hearing of Neonates in a Tertiary Healthcare Centre

Congenital hearing loss is hearing loss present in a child at birth or soon after birth. It is a debilitating condition with the potential for lifelong disability. It is thought to be multifactorial in aetiology with both genetic (autosomal and X-linked) and acquired causes (such as maternal infections, drug intake, trauma). Gestational Diabetes Mellitus (GDM) is a relatively common condition found in pregnant females but is a rather understudied risk factor in terms of congenital hearing loss. GDM is easily treatable which makes the hearing loss due to it easily preventable. (1) Determine correlation between Gestational Diabetes Mellitus and congenital hearing loss in neonates. (2) Calculate the prevalence of Gestational Diabetes Mellitus related congenital hearing loss. A two-step screening process was used for hearing evaluation of neonates with normal mothers (non-exposed) and neonates with mothers suffering from GDM (exposed) through Otoacoustic emission (OAE) and Brainstem Evoked Response Audiometry (BERA). (1) The difference of neonates diagnosed with hearing impairment in exposed and non-exposed group was statistically significant with a p-value of 0.024. OR 2.1538 95% CI 0.6120-7.5796, p < 0.05. (2) Prevalence of hearing loss in neonates of GDM mothers: 13.3%. Through rigorous exclusion of the already known risk factors for congenital hearing loss, Gestational Diabetes Mellitus has been isolated as an independent risk factor for neonatal hearing impairment. We hope to identify additional cases of congenital hearing loss early leading to a decrease in disease burden.

Early-life dietary exposures mediate persistent shifts in the gut microbiome and visceral fat metabolism

In utero dietary exposures are linked to the development of metabolic syndrome in adult offspring. These dietary exposures can potentially impact gut microbial composition and offspring metabolic health. Female BALB/c mice were administered a lard, lard + flaxseed oil, high sugar, or control diet 4 wk before mating, throughout mating, pregnancy, and lactation. Female offspring were offered low-fat control diet at weaning. Fecal 16S sequencing was performed. Untargeted metabolomics was performed on visceral adipose tissue (VAT) of adult female offspring. Immunohistochemistry was used to determine adipocyte size, VAT collagen deposition, and macrophage content. Hippurate was administered via weekly intraperitoneal injections to low-fat and high-fat diet-fed female mice and VAT fibrosis and collagen 1A (COL1A) were assessed by immunohistochemistry. Lard diet exposure was associated with elevated body and VAT weight and dysregulated glucose metabolism. Lard + flaxseed oil attenuated these effects. Lard diet exposures were associated with increased adipocyte diameter and VAT macrophage count. Lard + flaxseed oil reduced adipocyte diameter and fibrosis compared with the lard diet. Hippurate-associated bacteria were influenced by lard versus lard + flax exposures that persisted to adulthood. VAT hippurate was increased in lard + flaxseed oil compared with lard diet. Hippurate supplementation mitigated VAT fibrosis pathology. Maternal high-fat lard diet consumption resulted in long-term metabolic and gut microbiome programming in offspring, impacting VAT inflammation and fibrosis, and was associated with reduced VAT hippurate content. These traits were not observed in maternal high-fat lard + flaxseed oil diet-exposed offspring. Hippurate supplementation reduced VAT fibrosis. These data suggest that detrimental effects of early-life high-fat lard diet exposure can be attenuated by dietary omega-3 polyunsaturated fatty acid supplementation.

Associations of ozone exposure with gestational diabetes mellitus and glucose homeostasis: Evidence from a birth cohort in Shanghai, China

BACKGROUND

Associations between individual exposure to ozone (O₃) and gestational diabetes mellitus (GDM) have rarely been investigated, and critical windows of O₃ exposure for GDM have not been identified.

OBJECTIVES

We aimed to explore the associations of gestational O₃ exposure with GDM and glucose homeostasis as well as to identify the potential critical windows.

METHODS

A total of 7834 pregnant women were included. Individual O₃ exposure concentrations were evaluated using a high temporal-spatial resolution model. Each participant underwent an oral glucose tolerance test (OGTT) to screen for GDM between 24 and 28 gestational weeks. Multiple logistic and multiple linear regression models were used to estimate the associations of O₃ with GDM risks and with blood glucose levels of OGTT, respectively. Distributed lag nonlinear models (DLNMs) were used to estimate the critical windows of O₃ exposure for GDM.

RESULTS

Nearly 13.29 % of participants developed GDM. After controlling for covariates, we observed increased GDM risks per IQR increment of O₃ exposure in the first trimester (OR = 1.738, 95 % CI: 1.002-3.016) and the first two trimesters (OR = 1.576, 95 % CI: 1.005-2.473). Gestational O₃ exposure was positively associated with increased fasting blood glucose (the first trimester: β = 2.964, 95 % CI: 1.529-4.398; the first two trimesters: β = 1.620, 95 % CI: 0.436-2.804) and 2 h blood glucose (the first trimester: β = 6.569, 95 % CI: 1.775-11.363; the first two trimesters: β = 6.839, 95 % CI: 2.896-10.782). We also observed a concentration-response relationship of gestational O₃ exposure with GDM risk, as well as fasting and 2 h blood glucose levels. Additionally, 5-10 gestational weeks was identified as a critical window of O₃ exposure for GDM development.

CONCLUSION

In summary, we found that gestational O₃ exposure disrupts glucose homeostasis and increases the risk of GDM in pregnant women. Furthermore, 5-10 gestational weeks could be a critical window for the effects of O₃ exposure on GDM.

Secular trend for increasing birthweight in offspring of pregnant women with type 1 diabetes: is improved placentation the reason?

Despite enormous progress in managing blood glucose levels, pregnancy in women with type 1 diabetes still carries risks for the growing fetus. While, previously, fetal undergrowth was not uncommon in these women, with improved maternal glycaemic control we now see an increased prevalence of fetal overgrowth. Besides short-term implications, offspring of women with type 1 diabetes are more likely to become obese and to develop diabetes and features of the metabolic syndrome. Here, we argue that the increase in birthweight is paradoxically related to improved glycaemic control in the pre- and periconceptional periods. Good glycaemic control reduces the prevalence of microangiopathy and improves placentation in early pregnancy, which may lead to unimpeded fetal nutrition. Even mild maternal hyperglycaemia may then later result in fetal overnutrition. This notion is supported by circumstantial evidence that lower HbA_1c levels as well as increases in markers of placental size and function in early pregnancy are associated with large-for-gestational age neonates. We also emphasise that neonates with normal birthweight can have excessive fat deposition. This may occur when poor placentation leads to initial fetal undergrowth, followed by fetal overnutrition due to maternal hyperglycaemia. Thus, the complex interaction of glucose levels during different periods of pregnancy ultimately determines the risk of adiposity, which can occur in fetuses with both normal and elevated birthweight. Prevention of fetal adiposity calls for revised goal setting to enable pregnant women to maintain blood glucose levels that are closer to normal. This could be supported by continuous glucose monitoring throughout pregnancy and appropriate maternal gestational weight gain. Future research should consider the measurement of adiposity in neonates.

Maternal and neonatal outcomes of singleton versus twin pregnancies complicated by gestational diabetes mellitus: A systematic review and meta-analysis

BACKGROUND

There is limited evidence exploring the maternal and neonatal complications of gestational diabetes mellitus (GDM) following singleton or twin pregnancies. Further, there have been no reviews completed examining the possible risk factors associated with GDM in singleton compared to twin pregnancies. This study assesses the impact of GDM in singleton and twin pregnancies on maternal and neonatal outcomes.

METHODS

From 1954 to December 2021, a thorough literature search was conducted in the EMBASE, Cochrane, MEDLINE, ScienceDirect, and Google Scholar databases and search engines. The risk of bias was calculated using the Newcastle Ottawa (NO) scale. A random-effects model was applied and interpreted as pooled odds ratio (OR) with 95% confidence intervals (CI).

RESULTS

Eight studies satisfied the inclusion criteria, with the quality of most studies being good to satisfactory. The risk of caesarean section (pooled OR = 0.32; 95%CI: 0.22 to 0.46), small-for-gestational age (SGA) neonates (pooled OR = 0.40; 95%CI: 0.19 to 0.84), preterm delivery (pooled OR = 0.07; 95%CI: 0.06 to 0.09), respiratory morbidity (pooled OR = 0.26; 95%CI: 0.19 to 0.37), neonatal hyperbilirubinemia (pooled OR = 0.19; 95%CI: 0.10 to 0.40), and NICU admission (pooled OR = 0.18; 95%CI: 0.14 to 0.25) was significantly lower in singleton pregnancies with GDM than in twin pregnancies with GDM.

CONCLUSION

Maternal outcomes like caesarean section and neonatal outcomes like SGA neonates, preterm delivery, respiratory morbidity, hyperbilirubinemia, and NICU admission were significantly greater in twin pregnancies with GDM. It is important for clinicians and policymakers to focus intervention strategies on twin pregnancies with GDM.

Maternal and fetal predictors of anthropometry in the first year of life in offspring of women with GDM

INTRODUCTION

Gestational Diabetes Mellitus (GDM) carries an increased risk for adverse perinatal and longer-term cardiometabolic consequences in offspring. This study evaluated the utility of maternal anthropometric, metabolic and fetal (cord blood) parameters to predict offspring anthropometry up to 1 year in pregnancies with GDM.

MATERIALS AND METHODS

In this prospective analysis of the MySweetheart study, we included 193/211 women with GDM that were followed up to 1 year postpartum. Maternal predictors included anthropometric (pre-pregnancy BMI, gestational weight gain (GWG), weight and fat mass at the 1^st GDM visit), and metabolic parameters (fasting insulin and glucose, Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), Quantitative insulin-sensitivity check index (QUICKI), HbA1c, triglycerides, and high-density lipoprotein (HDL) at the 1^st visit and HbA1c at the end of pregnancy). Fetal predictors (N=46) comprised cord blood glucose and insulin, C-Peptide, HOMA-IR, triglycerides and HDL. Offspring outcomes were anthropometry at birth (weight/weight z-score, BMI, small and large for gestational age (SGA,LGA)), 6-8 weeks and 1 year (weight z-score, BMI/BMI z-score, and the sum of 4 skinfolds).

RESULTS

In multivariate analyses, birth anthropometry (weight, weight z-score, BMI and/or LGA), was positively associated with cord blood HDL and HbA1c at the 1^st GDM visit, and negatively with maternal QUICKI and HDL at the 1^st GDM visit (all p ≤ 0.045). At 6-8 weeks, offspring BMI was positively associated with GWG and cord blood insulin, whereas the sum of skinfolds was negatively associated with HDL at the 1^st GDM visit (all p ≤0.023). At 1 year, weight z-score, BMI, BMI z-score, and/or the sum of skinfolds were positively associated with pre-pregnancy BMI, maternal weight, and fat mass at the 1^st GDM visit and 3^rd trimester HbA1c (all p ≤ 0.043). BMI z-score and/or the sum of skinfolds were negatively associated with cord blood C-peptide, insulin and HOMA-IR (all p ≤0.041).

DISCUSSION

Maternal anthropometric, metabolic, and fetal metabolic parameters independently affected offspring anthropometry during the 1^st year of life in an age-dependent manner. These results show the complexity of pathophysiological mechanism for the developing offspring and could represent a base for future personalized follow-up of women with GDM and their offspring.

Hyperglycemia in Pregnancy and Women's Health in the 21st Century

Hyperglycemia is the commonest medical condition affecting pregnancy and its incidence is increasing globally in parallel with the twin epidemics of diabetes and obesity. Both pre-pregnancy diabetes and gestational diabetes are associated with short term pregnancy complications, with the risk of immediate complications generally broadly rising with more severe hyperglycemia. In this article we firstly consider these risks and their optimal management during pregnancy and then broaden our scope to consider the long-term implications of hyperglycemia in pregnancy as it relates to overall maternal and offspring health in a life course perspective.

Dietary Advice to Support Glycaemic Control and Weight Management in Women with Type 1 Diabetes during Pregnancy and Breastfeeding

In women with type 1 diabetes, the risk of adverse pregnancy outcomes, including congenital anomalies, preeclampsia, preterm delivery, foetal overgrowth and perinatal death is 2-4-fold increased compared to the background population. This review provides the present evidence supporting recommendations for the diet during pregnancy and breastfeeding in women with type 1 diabetes. The amount of carbohydrate consumed in a meal is the main dietary factor affecting the postprandial glucose response. Excessive gestational weight gain is emerging as another important risk factor for foetal overgrowth. Dietary advice to promote optimized glycaemic control and appropriate gestational weight gain is therefore important for normal foetal growth and pregnancy outcome. Dietary management should include advice to secure sufficient intake of micro- and macronutrients with a focus on limiting postprandial glucose excursions, preventing hypoglycaemia and promoting appropriate gestational weight gain and weight loss after delivery. Irrespective of pre-pregnancy BMI, a total daily intake of a minimum of 175 g of carbohydrate, mainly from low-glycaemic-index sources such as bread, whole grain, fruits, rice, potatoes, dairy products and pasta, is recommended during pregnancy. These food items are often available at a lower cost than ultra-processed foods, so this dietary advice is likely to be feasible also in women with low socioeconomic status. Individual counselling aiming at consistent timing of three main meals and 2-4 snacks daily, with focus on carbohydrate amount with pragmatic carbohydrate counting, is probably of value to prevent both hypoglycaemia and hyperglycaemia. The recommended gestational weight gain is dependent on maternal pre-pregnancy BMI and is lower when BMI is above 25 kg/m2. Daily folic acid supplementation should be initiated before conception and taken during the first 12 gestational weeks to minimize the risk of foetal malformations. Women with type 1 diabetes are encouraged to breastfeed. A total daily intake of a minimum of 210 g of carbohydrate is recommended in the breastfeeding period for all women irrespective of pre-pregnancy BMI to maintain acceptable glycaemic control while avoiding ketoacidosis and hypoglycaemia. During breastfeeding insulin requirements are reported approximately 20% lower than before pregnancy. Women should be encouraged to avoid weight retention after pregnancy in order to reduce the risk of overweight and obesity later in life. In conclusion, pregnant women with type 1 diabetes are recommended to follow the general dietary recommendations for pregnant and breastfeeding women with special emphasis on using carbohydrate counting to secure sufficient intake of carbohydrates and to avoid excessive gestational weight gain and weight retention after pregnancy.

Genetic Risk Factors and Gene-Lifestyle Interactions in Gestational Diabetes

Paralleling the increasing trends of maternal obesity, gestational diabetes (GDM) has become a global health challenge with significant public health repercussions. In addition to short-term adverse outcomes, such as hypertensive pregnancy disorders and fetal macrosomia, in the long term, GDM results in excess cardiometabolic morbidity in both the mother and child. Recent data suggest that women with GDM are characterized by notable phenotypic and genotypic heterogeneity and that frequencies of adverse obstetric and perinatal outcomes are different between physiologic GDM subtypes. However, as of yet, GDM treatment protocols do not differentiate between these subtypes. Mapping the genetic architecture of GDM, as well as accurate phenotypic and genotypic definitions of GDM, could potentially help in the individualization of GDM treatment and assessment of long-term prognoses. In this narrative review, we outline recent studies exploring genetic risk factors of GDM and later type 2 diabetes (T2D) in women with prior GDM. Further, we discuss the current evidence on gene-lifestyle interactions in the development of these diseases. In addition, we point out specific research gaps that still need to be addressed to better understand the complex genetic and metabolic crosstalk within the mother-placenta-fetus triad that contributes to hyperglycemia in pregnancy.

Unique Metabolic Profiles Associate with Gestational Diabetes and Ethnicity in Low- and High-Risk Women Living in the UK

BACKGROUND

Gestational diabetes mellitus (GDM) is the most common global pregnancy complication; however, prevalence varies substantially between ethnicities, with South Asians (SAs) experiencing up to 3 times the risk of the disease compared with white Europeans (WEs). Factors driving this discrepancy are unclear, although the metabolome is of great interest as GDM is known to be characterized by metabolic dysregulation.

OBJECTIVES

The primary aim was to characterize and compare the metabolic profiles of GDM in SA and WE women (at <28 wk of gestation) from the Born in Bradford (BIB) prospective birth cohort in the United Kingdom.

METHODS

In total, 146 fasting serum metabolites, from 2,668 pregnant WE and 2,671 pregnant SA women (average BMI 26.2 kg/m2, average age 27.3 y) were analyzed using partial least squares discriminatory analyses to characterize GDM status. Linear associations between metabolite values and post-oral glucose tolerance test measures of dysglycemia (fasting glucose and 2 h postglucose) were also examined.

RESULTS

Seven metabolites associated with GDM status in both ethnicities (variable importance in projection ≥1), whereas 6 additional metabolites associated with GDM only in WE women. Unique metabolic profiles were observed in healthy-weight women who later developed GDM, with distinct metabolite patterns identified by ethnicity and BMI status. Of the metabolite values analyzed in relation to dysglycemia, lactate, histidine, apolipoprotein A1, HDL cholesterol, and HDL2 cholesterol associated with decreased glucose concentration, whereas DHA and the diameter of very low-density lipoprotein particles (nm) associated with increased glucose concertation in WE women, and in SAs, albumin alone associated with decreased glucose concentration.

CONCLUSIONS

This study shows that the metabolic risk profile for GDM differs between WE and SA women enrolled in BiB in the United Kingdom. This suggests that etiology of the disease differs between ethnic groups and that ethnic-appropriate prevention strategies may be beneficial.

Crucial nuances in understanding (mis)associations between the neonatal microbiome and Cesarean delivery

As rates of Cesarean delivery and common non-communicable disorders (NCDs), such as obesity, metabolic disease, and atopy/asthma, have concomitantly increased in recent decades, investigators have attempted to discern a causal link. One line of research has led to a hypothesis that Cesarean birth disrupts the presumed normal process of colonization of the neonatal microbiome with vaginal microbes, yielding NCDs later in life. However, a direct link between a disrupted microbiota transfer at time of delivery and acute and/or chronic illness in infants born via Cesarean has not been causally established. Microbiota seeding from maternal vaginal or stool sources has been preliminarily evaluated as an intervention designed to compensate for the lack of (or limited) exposure to such sources among Cesarean-delivered neonates. However, to date, clinical trials have yet to show a clear health benefit with neonatal 'vaginal seeding' practices. Until the long-term effects of these microbiome alterations can be fully determined, it is paramount to conduct parallel meaningful and mechanistic-minded interrogations of the impact of clinically modifiable maternal, nutritional, or environmental exposure on the functional microbiome over the duration of pregnancy and lactation to determine their role in the mitigation of childhood and adult NCDs.

Epigenetic Modifications in Obesity and Type 2 Diabetes

Obesity is a chronic condition that is also a risk factor of several other chronic conditions including type 2 diabetes. The effects of maternal obesity and type 2 diabetes on fetal development and offspring health are mediated through the transmission of epigenetic modifications in addition to the possible permanent changes of the organs caused by the intrauterine environment hypothesized by the Developmental Origins of Health and Disease (DOHaD) theory. Epigenetic modifications can be altered by environmental factors including dietary and lifestyle factors. The current priorities include identification and confirmation of the specific epigenetic biomarkers associated with obesity and type 2 diabetes in human subjects and identification of the dietary and lifestyle factors that contribute to each of the identified specific epigenetic biomarkers.

How Do the Different Types of Maternal Diabetes during Pregnancy Influence Offspring Outcomes?

Background/Aim of the study: Exposure to maternal diabetes is considered one of the most common in utero insults that can result in an increased risk of complications later in life with a permanent effect on offspring health. In this study, we aim to assess the level of risk associated with each type of maternal diabetes on obesity, glucose intolerance, cardiovascular diseases (CVD), and neurodevelopmental disorders in offspring. Methods: We conducted a systematic review of the literature utilizing PubMed for studies published between January 2007 and March 2022. Our search included human cohorts and case control studies following offspring exposed at least to two different types of maternal diabetes clearly identified during pregnancy. Collected outcomes included prevalence, incidence, odds ratio, hazard ratio and risk ratio. Results: Among 3579 published studies, 19 cohorts were eligible for inclusion in our review. The risks for overweight, obesity, type 2 diabetes (T2D), glucose intolerance, metabolic syndrome, and CVD were increased for all types of maternal diabetes during pregnancy. The risk of overweight or obesity in infancy and in young adults was similar between gestational diabetes mellitus (GDM) and type 1 diabetes (T1D). The risk for T2D or abnormal glucose tolerance was double for offspring from GDM mothers compared to offspring from T1D mothers. In contrast, the risk for T1D in offspring at any age until young adulthood was increased when mothers had T1D compared to GDM and T2D. The risk for CVD was similar for all types of maternal diabetes, but more significant results were seen in the occurrence of heart failure and hypertension among offspring from T2D mothers. The risk of autism spectrum disorders and attention deficit/hyperactivity disorders was mainly increased after in utero exposure to preexisting T1D, followed by T2D. Conclusions: Offspring of diabetic mothers are at increased risk for multiple adverse outcomes with the highest risk detected among offspring from T2D mothers. Future work warrants large multiethnic prospective cohort studies that aim to identify the risks associated with each type of maternal diabetes separately.

Factors Influencing Adverse Pregnancy Outcomes in Gestational Diabetes Mellitus

Objective

Analysis of gestational diabetes risk factors and their impact on pregnancy outcomes.

Methods

A retrospective analysis of pregnant women who delivered in the obstetrics ward of a tertiary hospital was performed, and the pregnant women were divided into a case group and a control group according to their compliance with the diagnostic criteria of GDM. The underlying pregnancy, delivery, and pregnancy outcomes of both groups were statistically analyzed.

Results

The detection rate and incidence rate of gestational diabetes were 13.0%, and the incidence rate was 14.5% compared to pregnancy and childbirth complications between the two groups. No statistical differences in placental weight and cord length were found compared to the sex of the newborns by comparing the basic profile of the two groups of perinatal infants. There was no statistical difference between fetal growth restriction and neonatal abnormalities, while there was a statistical difference in neonatal outcomes between the two groups.

Conclusion

Age, family history, and weight are the risk factors for GDM.

Effects of Gestational Sleep Patterns and Their Changes on Maternal Glycemia and Offspring Physical Growth in Early Life

Maternal sleep patterns during pregnancy are drawing increased attention to examine its role in the regulation of maternal glycemia and physical growth of offspring within 24 months. Among 3329 eligible mother−child pairs included in the Shanghai Maternal−Child Pairs Cohort, sleep patterns of pregnant women were assessed by Pittsburgh Sleep Quality Index and objective measurement in early and late pregnancy. Offspring physical growth within 24 months was primarily indicated by the body mass index Z-score (BAZ), catch-up growth, and overweight/obesity. In total, 3329 and 382 pregnant women were included with subjectively assessed and objectively measured sleep pattern, respectively. The increased risk of GDM was associated with maternal night-time sleep duration ≥8.5 h in early pregnancy, or sleep quality change from poor to good during pregnancy (OR = 1.48; 95% CI, 1.06 to 2.07). In the GDM group, the effect of sleep duration in early pregnancy on overweight/obesity in offspring within 24 months showed a U-shaped curve, with a 1.73-fold and 1.43-fold increased risk of overweight/obesity of offspring in pregnant women with <7.5 or ≥8.5 h of sleep duration, respectively. A good gestational sleep pattern was required to reduce the risk of GDM and offspring overweight/obesity within 24 months.

The Combined Effect of Birth Weight and Lifestyle on Clustered Cardio-Metabolic Risk Factors in Children and Adolescents: A National School-Based Cross-Sectional Survey

Background: Due to the adverse effects of cardio-metabolic risk factors (CMRFs) in children and adolescents on their current and later life health, and the growing evidence that birth weight and lifestyle have on CMRFs, we aimed to estimate the combined effect of birth weight and lifestyle on clustered CMRFs in children and adolescents. Methods: We enrolled 11,509 participants aged 7–18 years old in a national school-based cross-sectional study in seven provinces in China in 2013. Information on CMRFs was collected through anthropometric measurements and blood sample testing. Information on birth weight, lifestyle and other basic information were investigated through children and adolescents’ as well as parents’ questionnaires. The generalized linear mixed model was applied to estimate the odd ratio (OR) and 95% confidence interval (95% CI) for the associations between CMRFs, clustered CMRFs and birth weight, lifestyle, and the combinations of birth weight and lifestyle. Results: Overall, the prevalence of clustered CMRFs was 3.6% in children and adolescents aged 7–18 years, higher in boys (4.4%) than girls (2.9%). The combination of LBW/ideal lifestyle (OR = 2.00, 95% CI: 1.07–3.72) was associated with higher risk of clustered CMRFs, as well as in adolescents aged 13–18 years and in boys. The combination of HBW/poor lifestyle (OR = 1.74, 95% CI: 1.13–2.68) was related to elevated risk of clustered CMRFs, especially in children aged 7–12 years. Conclusions: CMRFs in Chinese children and adolescents is concerning, ideal lifestyle could weaken the association of birth weight with clustered CMRFs, especially in younger age, indicating that programs to prevent abnormal birth weight or poor lifestyle or both among children and adolescents may reduce CMRFs in China.

Glucose Intolerance in Pregnancy and Offspring Obesity in Late Adolescence

OBJECTIVE

Gestational hyperglycemia is associated with deleterious neonatal outcomes, but long-term risks for offspring obesity are less clear. We estimated the odds for offspring adolescent overweight and obesity among mothers with gestational glucose intolerance.

RESEARCH DESIGN AND METHODS

In a mother-offspring historical cohort, the Israel military conscription data set was linked to a large health maintenance organization. Included were women who were evaluated at adolescence and underwent two-step gestational diabetes screening (mean age, 31 years) with a 50-g glucose challenge test (GCT), followed by a 100-g oral glucose tolerance test (OGTT) if the result was abnormal. Glucose tolerance categories included gestational normoglycemia, abnormal GCT with normal OGTT, impaired glucose tolerance (IGT; one abnormal OGTT value), and gestational diabetes. The primary outcome was offspring overweight/obesity (BMI ≥85th percentile) at adolescence, measured prior to military conscription. Logistic regression models were applied.

RESULTS

Of 33,482 mother-offspring pairs, overweight and obesity were observed in 6,516 offspring. Across increasing categories of pregnancy glycemia, the proportions of offspring with adolescent overweight/obesity increased: normoglycemia, 19%; abnormal GCT with normal OGTT, 22%; gestational IGT, 24%; and gestational diabetes, 25% (P < 0.0001). Corresponding odds ratios after adjustment for the mother's late adolescent characteristics (sociodemographic confounders and BMI) and pregnancy age were 1.2 (95% CI 1.1-1.4), 1.3 (1.2-1.5), and 1.4 (1.3-1.6), respectively. Further adjustment for offspring birth weight percentile and sociodemographic variables did not materially change results. Associations were more pronounced with increasing obesity severity.

CONCLUSIONS

Gestational glucose intolerance, including categories not meeting the gestational diabetes threshold, was associated with increased odds for offspring overweight/obesity at late adolescence.

Genome-Wide Placental Gene Methylations in Gestational Diabetes Mellitus, Fetal Growth and Metabolic Health Biomarkers in Cord Blood

Gestational diabetes mellitus (GDM) "program" an elevated risk of metabolic syndrome in the offspring. Epigenetic alterations are a suspected mechanism. GDM has been associated with placental DNA methylation changes in some epigenome-wide association studies. It remains unclear which genes or pathways are affected, and whether any placental differential gene methylations are correlated to fetal growth or circulating metabolic health biomarkers. In an epigenome-wide association study using the Infinium MethylationEPIC Beadchip, we sought to identify genome-wide placental differentially methylated genes and enriched pathways in GDM, and to assess the correlations with fetal growth and metabolic health biomarkers in cord blood. The study samples were 30 pairs of term placentas in GDM vs. euglycemic pregnancies (controls) matched by infant sex and gestational age at delivery in the Shanghai Birth Cohort. Cord blood metabolic health biomarkers included insulin, C-peptide, proinsulin, IGF-I, IGF-II, leptin and adiponectin. Adjusting for maternal age, pre-pregnancy BMI, parity, mode of delivery and placental cell type heterogeneity, 256 differentially methylated positions (DMPs,130 hypermethylated and 126 hypomethylated) were detected between GDM and control groups accounting for multiple tests with false discovery rate <0.05 and beta-value difference >0.05. WSCD2 was identified as a differentially methylated gene in both site- and region-level analyses. We validated 7 hypermethylated (CYP1A2, GFRA1, HDAC4, LIMS2, NAV3, PAX6, UPK1B) and 10 hypomethylated (DPP10, CPLX1, CSMD2, GPR133, NRXN1, PCSK9, PENK, PRDM16, PTPRN2, TNXB) genes reported in previous epigenome-wide association studies. We did not find any enriched pathway accounting for multiple tests. DMPs in 11 genes (CYP2D7P1, PCDHB15, ERG, SIRPB1, DKK2, RAPGEF5, CACNA2D4, PCSK9, TSNARE1, CADM2, KCNAB2) were correlated with birth weight (z score) accounting for multiple tests. There were no significant correlations between placental gene methylations and cord blood biomarkers. In conclusions, GDM was associated with DNA methylation changes in a number of placental genes, but these placental gene methylations were uncorrelated to the observed metabolic health biomarkers (fetal growth factors, leptin and adiponectin) in cord blood. We validated 17 differentially methylated placental genes in GDM, and identified 11 differentially methylated genes relevant to fetal growth.

DNA Methylation and Gene Expression in Blood and Adipose Tissue of Adult Offspring of Women with Diabetes in Pregnancy—A Validation Study of DNA Methylation Changes Identified in Adolescent Offspring

Maternal gestational diabetes and obesity are associated with adverse outcomes in offspring, including increased risk of diabetes and cardiovascular diseases. Previously, we identified a lower DNA methylation degree at genomic sites near the genes ESM1, MS4A3, and TSPAN14 in the blood cells of adolescent offspring exposed to gestational diabetes and/or maternal obesity in utero. In the present study, we aimed to investigate if altered methylation and expression of these genes were detectable in blood, as well in the metabolically relevant subcutaneous adipose tissue, in a separate cohort of adult offspring exposed to gestational diabetes and obesity (O-GDM) or type 1 diabetes (O-T1D) in utero, compared with the offspring of women from the background population (O-BP). We did not replicate the findings of lower methylation of ESM1, MS4A3, and TSPAN14 in blood from adults, either in O-GDM or O-T1D. In contrast, in adipose tissue of O-T1D, we found higher MS4A3 DNA methylation, which will require further validation. The adipose tissue ESM1 expression was lower in O-GDM compared to O-BP, which in turn was not associated with maternal pre-pregnancy BMI nor the offspring’s own adiposity. Adipose tissue TSPAN14 expression was slightly lower in O-GDM compared with O-BP, but also positively associated with maternal pre-pregnancy BMI, as well as offspring’s own adiposity and HbA1c levels. In conclusion, the lower DNA methylation in blood from adolescent offspring exposed to GDM could not be confirmed in the present cohort of adult offspring, potentially due to methylation remodeling with increased aging. In offspring adipose tissue, ESM1 expression was associated with maternal GDM, and TSPAN14 expression was associated with both maternal GDM, as well as pre-pregnancy BMI. These altered expression patterns are potentially relevant to the concept of developmental programming of cardiometabolic diseases and require further studies.

Associations of Gestational Diabetes Mellitus and Excessive Gestational Weight Gain with Offspring Obesity Risk

OBJECTIVE

Gestational diabetes mellitus (GDM) and gestational weight gain (GWG) are important risk factors that are known to affect offspring growth, but these outcomes are inconsistent and it remains unknown if both risk factors have a synergetic effect on early childhood growth. The present study aimed to conduct offspring body mass index-for-age Z-scores (BMIZ) trajectories and to evaluate the independent and interactive effect of the status of GDM and excessive GWG on the risks of overweight/obesity from birth to 24 months of age.

METHODS

A total of 7949 mother-child pairs were enrolled in this study. The weight and length of children were measured at birth, 6, 12, and 24 months of age to calculate BMIZ.

RESULTS

The status of GDM was positively associated with offspring BMIZ and risk of macrosomia at birth but was not associated with offspring BMIZ or the risks of overweight/obesity at 6, 12, and 24 months of age. In contrast, excessive GWG was positively linked to offspring BMIZ, the stable high BMIZ trajectory pattern, and risks of overweight/obesity in the first 24 months of age. These two risk factors also had a significant synergistic effect on macrosomia at birth, but the interactive effect was only significant in boys during the follow-up years in the sex-stratified analyses.

CONCLUSION

The maternal GWG was a more pronounced predictor than GDM with relation to BMIZ and risk of overweight/obesity in early childhood. The interactive effect between these risk factors on offspring overweight/obesity may vary by sex.

Recent Experimental Studies of Maternal Obesity, Diabetes during Pregnancy and the Developmental Origins of Cardiovascular Disease

Globally, cardiovascular disease remains the leading cause of death. Most concerning is the rise in cardiovascular risk factors including obesity, diabetes and hypertension among youth, which increases the likelihood of the development of earlier and more severe cardiovascular disease. While lifestyle factors are involved in these trends, an increasing body of evidence implicates environmental exposures in early life on health outcomes in adulthood. Maternal obesity and diabetes during pregnancy, which have increased dramatically in recent years, also have profound effects on fetal growth and development. Mounting evidence is emerging that maternal obesity and diabetes during pregnancy have lifelong effects on cardiovascular risk factors and heart disease development. However, the mechanisms responsible for these observations are unknown. In this review, we summarize the findings of recent experimental studies, showing that maternal obesity and diabetes during pregnancy affect energy metabolism and heart disease development in the offspring, with a focus on the mechanisms involved. We also evaluate early proof-of-concept studies for interventions that could mitigate maternal obesity and gestational diabetes-induced cardiovascular disease risk in the offspring.

Identification and Validation of miR-222-3p and miR-409-3p as Plasma Biomarkers in Gestational Diabetes Mellitus Sharing Validated Target Genes Involved in Metabolic Homeostasis

Gestational diabetes mellitus (GDM) causes both maternal and fetal adverse outcomes. The deregulation of microRNAs (miRNAs) in GDM suggests their involvement in GDM pathogenesis and complications. Exosomes are extracellular vesicles (EVs) of endosomal origin, released via exocytosis into the extracellular compartment. Through EVs, miRNAs are delivered in distant target cells and are able to affect gene expression. In this study, miRNA expression was analyzed to find new miRNAs that could improve GDM classification and molecular characterization. MiRNA were profiled in total plasma and EVs in GDM patients and normal glucose tolerance (NGT) women. Samples were collected at third trimester of gestation from two diabetes centers. MiRNA expression was profiled in a discovery cohort using the multiplexed NanoString nCounter Human v3 miRNA. Validation analysis was performed in a second independent cohort using RT-qPCR. A set of miRNAs resulted to be differentially expressed (DE) in total plasma and EVs in GDM. Among them, total plasma miR-222-3p and miR-409-3p were validated in the independent cohort. MiR-222-3p levels correlated with fasting plasma glucose (FPG) (p < 0.001) and birth weight (p = 0.012), whereas miR-409-3p expression correlated with FPG (p < 0.001) and inversely with gestational age (p = 0.001). The major validated target genes of the deregulated miRNAs were consistently linked to type 2 diabetes and GDM pathophysiology. MiR-222-3p and miR-409-3p are two circulating biomarkers that could improve GDM classification power and act in the context of the molecular events leading to the metabolic alterations observed in GDM.

Effect of the New Nordic Diet compared with usual care on glucose control in gestational diabetes mellitus: Study protocol for the randomized controlled trial intervention with new Nordic DIet in women with GestatiOnal diabetes mellitus (iNDIGO)

BACKGROUND

Gestational diabetes mellitus (GDM) is a pregnancy complication associated with short- and long-term health consequences for mother and child. First line treatment is diet and exercise but there is a recognized knowledge gap as to what diet treatment is optimal. A healthy Nordic diet has been associated with improved health but no studies in women with GDM exist. The New Nordic Diet (NND) is an initiative with the purpose to develop a healthy Nordic diet including foods with the potential to grow in Nordic countries; including fruit, berries, vegetables, whole-grain cereal products, nuts, fish, and rapeseed oil. The purpose of the intervention with new Nordic DIet in women with GestatiOnal diabetes mellitus (iNDIGO) is to test if the NND compared with usual care improves glucose control in women with GDM.

METHODS

The iNDIGO study is a randomized parallel controlled trial where 50 women with GDM will be randomized to either an NND or usual care for 14 days (30-32 weeks of gestation). Participants in the NND group will receive menus and food bags containing foods to be consumed. Primary outcome is glycemic control (time in target) measured using continuous glucose monitoring. Compliance to the dietary intervention will be tested using dietary biomarkers and adherence questionnaires.

CONCLUSION

Diet treatment represents first line treatment in GDM but it remains unclear what type of diets are effective. iNDIGO is an efficacy study and will provide evidence as to whether a healthy Nordic diet can improve glucose control in women with GDM.

TRIAL REGISTRATION

ClinicalTrials.gov registration Number: NCT04169243. Registered 19 November 2019, https://clinicaltrials.gov/ct2/show/NCT04169243.