Treatment of Gestational Diabetes Mellitus Diagnosed Early in Pregnancy

Earlier detection of gestational diabetes impacts on medication requirements, neonatal and maternal outcomes

AIM

Gestational diabetes (GD) is a global health concern with significant implications for maternal and neonatal outcomes. This study investigates the association between early GD (eGD) diagnosis (<24 weeks), pharmacotherapy requirements and adverse neonatal outcomes.

MATERIALS AND METHODS

A cohort of 369 pregnant women underwent a 75-g oral glucose tolerance test. Maternal variables, pharmacotherapy prescriptions and neonatal outcomes were analysed employing t-tests, χ2 tests, and logistic regression. A p < .05 was considered significant.

RESULTS

Early GD increased the odds of neonatal hypoglycaemia [odds ratio (OR): 18.57, p = .013] and respiratory distress syndrome (OR: 4.75, p = .034). Nutritional therapy prescription by an accredited nutritionist was the most common treatment in women diagnosed after 24 weeks, but those with eGD required more frequently specialized nutritional consulting + metformin to achieve glycaemic control (p = .027). eGD was associated with a higher requirement of nutritional therapy prescription + metformin (OR: 2.26, 95% confidence interval: 1.25-4.09, p = .007) and with maternal hyperglycaemia during the post-partum period at 2 h of the oral glucose tolerance test (OR: 1.03, 95% confidence interval: 1.02-1.13, p = .024).

CONCLUSION

Timely diagnosis and personalized treatment of GD are desirable because an earlier presentation is related to a higher risk of adverse neonatal and maternal outcomes.

Time to Move Beyond a Binary Criterion for Gestational Diabetes?

Over the years, several international guidelines have been developed by specialist organizations for the diagnosis of gestational diabetes mellitus (GDM). However, these guidelines vary and lack consensus on what level of glycemia defines GDM and worryingly, there is now evidence of over- or- under-diagnosis of women with GDM by current criteria. Towards this end, the National Priorities Research Program (NPRP) funded a program of research aimed at elucidating the problem with GDM diagnosis. It was determined, on completion of the project, that the solution required diagnosis of graded levels of dysglycemia in pregnancy and not just a diagnosis of presence or absence of GDM. A new diagnostic criterion (called the NPRP criterion) was created based on a single numerical summary of the three readings from the oral glucose tolerance test (GTT) that diagnosed women in pregnancy into four levels: normal, impaired, GDM and high risk GDM. This paper now examines existing GDM criteria vis-à-vis the NPRP criterion. It is noted that no significant change has happened over the years for existing criteria except for a gradual reduction in the threshold values of individual time-points or the number of time points, bringing us towards over-diagnosis of GDM in pregnancy. The new criterion unifies all readings from the GTT into one numerical value and, because it results in four levels of glycemia, represents a new way forwards for GDM diagnosis and can potentially reduce the rates of under diagnosis and over diagnosis of GDM.

Consensus guidance for monitoring individuals with islet autoantibody-positive pre-stage 3 type 1 diabetes

Given the proven benefits of screening to reduce diabetic ketoacidosis (DKA) likelihood at the time of stage 3 type 1 diabetes diagnosis, and emerging availability of therapy to delay disease progression, type 1 diabetes screening programmes are being increasingly emphasised. Once broadly implemented, screening initiatives will identify significant numbers of islet autoantibody-positive (IAb+) children and adults who are at risk of (confirmed single IAb+) or living with (multiple IAb+) early-stage (stage 1 and stage 2) type 1 diabetes. These individuals will need monitoring for disease progression; much of this care will happen in non-specialised settings. To inform this monitoring, JDRF in conjunction with international experts and societies developed consensus guidance. Broad advice from this guidance includes the following: (1) partnerships should be fostered between endocrinologists and primary-care providers to care for people who are IAb+; (2) when people who are IAb+ are initially identified there is a need for confirmation using a second sample; (3) single IAb+ individuals are at lower risk of progression than multiple IAb+ individuals; (4) individuals with early-stage type 1 diabetes should have periodic medical monitoring, including regular assessments of glucose levels, regular education about symptoms of diabetes and DKA, and psychosocial support; (5) interested people with stage 2 type 1 diabetes should be offered trial participation or approved therapies; and (6) all health professionals involved in monitoring and care of individuals with type 1 diabetes have a responsibility to provide education. The guidance also emphasises significant unmet needs for further research on early-stage type 1 diabetes to increase the rigour of future recommendations and inform clinical care.

Early pregnancy HbA1c as the first screening test for gestational diabetes: results from three prospective cohorts

BACKGROUND

More than 90% of gestational diabetes cases are estimated to occur in low-income and middle-income countries (LMICs). Most current guidelines recommend an oral glucose tolerance test (OGTT) at 24-28 weeks of gestation. The OGTT is burdensome, especially in LMICs, resulting in a high proportion of women not being screened. We aimed to develop a simple and effective screening strategy for gestational diabetes.

METHODS

STRiDE, a prospective cohort study, was set up in seven centres in south India and seven centres in western Kenya, and included pregnant women aged 18-50 years of age and at less than 16 weeks of gestation (<20 weeks in Kenya), confirmed by dating ultrasound. We assessed the efficacy of early pregnancy HbA1c (venous and capillary point-of-care), either alone or as part of a composite risk score with age, BMI, and family history of diabetes, in predicting gestational diabetes at 24-28 weeks of gestation, in two LMICs (India and Kenya) and in a UK multi-ethnic population from the PRiDE study. A key secondary outcome was to assess whether an early pregnancy composite risk score can reduce the need for OGTTs. Gestational diabetes was diagnosed using current WHO criteria.

FINDINGS

Between Feb 15, 2016, Dec 13, 2019, we enrolled 3070 participants in India and 4104 in Kenya. 4320 participants were included from the PRiDE cohort. Gestational diabetes prevalence by OGTT at 24-28 weeks was 19·2% in India, 3·0% in Kenya, and 14·5% in the UK. Early pregnancy HbA1c was independently associated with incidence of gestational diabetes at 24-28 weeks of gestation. Adjusted risk ratios were 1·60 (95% CI 1·19-2·16) in India, 3·49 (2·8-4·34) in Kenya, and 4·72 (3·82-5·82) in the UK. Composite risk score models that combined venous or point-of-care HbA1c with age, BMI, and family history of diabetes best predicted testing positive for gestational diabetes. A population-specific, two-threshold screening strategy of rule-in and rule-out gestational diabetes using early pregnancy composite risk score could reduce the requirement of OGTTs by 50-64%. For the HbA1c-alone model, the thresholds were 5·4% (rule in) and 4·9% (rule out) in India, 6·0% (rule in) and 5·2% (rule out) in Kenya, and 5·6% (rule in) and 5·2% (rule out) in the UK.

INTERPRETATION

Early pregnancy HbA1c offers a simple screening test for gestational diabetes, allowing those at highest risk to receive early intervention and greatly reduce the need for OGTTs. This can also be carried out using point-of-care HbA1c in LMICs.

FUNDING

UK Medical Research Council and the Indian Department of Biotechnology.

Epidemiology and management of gestational diabetes

Gestational diabetes is defined as hyperglycaemia first detected during pregnancy at glucose concentrations that are less than those of overt diabetes. Around 14% of pregnancies globally are affected by gestational diabetes; its prevalence varies with differences in risk factors and approaches to screening and diagnosis; and it is increasing in parallel with obesity and type 2 diabetes. Gestational diabetes direct costs are US$1·6 billion in the USA alone, largely due to complications including hypertensive disorders, preterm delivery, and neonatal metabolic and respiratory consequences. Between 30% and 70% of gestational diabetes is diagnosed in early pregnancy (ie, early gestational diabetes defined by hyperglycaemia before 20 weeks of gestation). Early gestational diabetes is associated with worse pregnancy outcomes compared with women diagnosed with late gestational diabetes (hyperglycaemia from 24 weeks to 28 weeks of gestation). Randomised controlled trials show benefits of treating gestational diabetes from 24 weeks to 28 weeks of gestation. The WHO 2013 recommendations for diagnosing gestational diabetes (one-step 75 gm 2-h oral glucose tolerance test at 24-28 weeks of gestation) are largely based on the Hyperglycemia and Adverse Pregnancy Outcomes Study, which confirmed the linear association between pregnancy complications and late-pregnancy maternal glycaemia: a phenomenon that has now also been shown in early pregnancy. Recently, the Treatment of Booking Gestational Diabetes Mellitus (TOBOGM) trial showed benefit in diagnosis and treatment of early gestational diabetes for women with risk factors. Given the diabesity epidemic, evidence for gestational diabetes heterogeneity by timing and subtype, and advances in technology, a life course precision medicine approach is urgently needed, using evidence-based prevention, diagnostic, and treatment strategies.

Call to action for a life course approach

Gestational diabetes remains the most common medical disorder in pregnancy, with short-term and long-term consequences for mothers and offspring. New insights into pathophysiology and management suggest that the current gestational diabetes treatment approach should expand from a focus on late gestational diabetes to a personalised, integrated life course approach from preconception to postpartum and beyond. Early pregnancy lifestyle intervention could prevent late gestational diabetes. Early gestational diabetes diagnosis and treatment has been shown to be beneficial, especially when identified before 14 weeks of gestation. Early gestational diabetes screening now requires strategies for integration into routine antenatal care, alongside efforts to reduce variation in gestational diabetes care, across settings that differ between, and within, countries. Following gestational diabetes, an oral glucose tolerance test should be performed 6-12 weeks postpartum to assess the glycaemic state. Subsequent regular screening for both dysglycaemia and cardiometabolic disease is recommended, which can be incorporated alongside other family health activities. Diabetes prevention programmes for women with previous gestational diabetes might be enhanced using shared decision making and precision medicine. At all stages in this life course approach, across both high-resource and low-resource settings, a more systematic process for identifying and overcoming barriers to preventative care and treatment is needed to reduce the current global burden of gestational diabetes.

Pathophysiology from preconception, during pregnancy, and beyond

Gestational diabetes is the most common medical complication in pregnancy. Historically, gestational diabetes was considered a pregnancy complication involving treatment of rising glycaemia late in the second trimester. However, recent evidence challenges this view. Pre-pregnancy and pregnancy-specific factors influence gestational glycaemia, with open questions regarding roles of non-glycaemic factors in the aetiology and consequences of gestational diabetes. Varying patterns of insulin secretion and resistance in early and late pregnancy underlie a heterogeneity of gestational diabetes in the timing and pathophysiological subtypes with clinical implications: early gestational diabetes and insulin resistant gestational diabetes subtypes are associated with a higher risk of pregnancy complications. Metabolic perturbations of early gestational diabetes can affect early placental development, affecting maternal metabolism and fetal development. Fetal hyperinsulinaemia can affect the development of multiple fetal tissues, with short-term and long-term consequences. Pregnancy complications are prevented by managing glycaemia in early and late pregnancy in some, but not all women with gestational diabetes. A better understanding of the pathophysiology and heterogeneity of gestational diabetes will help to develop novel management approaches with focus on improved prevention of maternal and offspring short-term and long-term complications, from pre-conception, throughout pregnancy, and beyond.

First-trimester fasting plasma glucose levels and progression to type 2 diabetes: A 5-year cohort study

OBJECTIVE

Impaired fasting glucose is a prediabetic condition defined as glucose levels of 100-125 mg/dL and is considered a risk factor for type 2 diabetes. However, this definition does not confer to pregnancy. The significance of first-trimester fasting glucose and future progression to diabetes is not well defined. Therefore, we aimed to evaluate the progression to type 2 diabetes according to first- trimester fasting plasma glucose levels, as compared with gestational diabetes, a well-established risk factor for diabetes, in up to 5-year follow-up postpartum.

METHODS

A retrospective analysis of 69 001 parturients, evaluating fasting plasma glucose levels measured during the first trimester. The primary outcome was the incidence of type 2 diabetes within 5 years post-delivery. Fasting plasma glucose levels were categorized in 10 mg/dL increments. Receiver operating characteristic-area under the curve (ROC-AUC) statistics and the Youden index were employed to identify the optimal fasting plasma glucose cutoff for progression to type 2 diabetes. Survival analysis was applied to calculate the adjusted hazard ratios (aHRs) for type 2 diabetes progression with further stratification to maternal obesity status.

RESULTS

The identified fasting plasma glucose cutoff for progression to type 2 diabetes was 86.5 mg/dL. This cut-off demonstrated superior performance compared with gestational diabetes diagnosis. Stratification by maternal obesity revealed enhanced predictive capabilities for type 2 diabetes, particularly among patients without obesity.

CONCLUSIONS

Increased first-trimester fasting plasma glucose levels are associated with progression to type 2 diabetes, at least as gestational diabetes. For patients without obesity, first-trimester fasting plasma glucose has a more pronounced impact on progression to diabetes.

Design, rationale and protocol for Glycemic Observation and Metabolic Outcomes in Mothers and Offspring (GO MOMs): an observational cohort study

INTRODUCTION

Given the increasing prevalence of both obesity and pre-diabetes in pregnant adults, there is growing interest in identifying hyperglycaemia in early pregnancy to optimise maternal and perinatal outcomes. Multiple organisations recommend first-trimester diabetes screening for individuals with risk factors; however, the benefits and drawbacks of detecting glucose abnormalities more mild than overt diabetes in early gestation and the best screening method to detect such abnormalities remain unclear.

METHODS AND ANALYSIS

The goal of the Glycemic Observation and Metabolic Outcomes in Mothers and Offspring study (GO MOMs) is to evaluate how early pregnancy glycaemia, measured using continuous glucose monitoring and oral glucose tolerance testing, relates to the diagnosis of gestational diabetes (GDM) at 24-28 weeks' gestation (maternal primary outcome) and large-for-gestational-age birth weight (newborn primary outcome). Secondary objectives include relating early pregnancy glycaemia to other adverse pregnancy outcomes and comprehensively detailing longitudinal changes in glucose over the course of pregnancy. GO MOMs enrolment began in April 2021 and will continue for 3.5 years with a target sample size of 2150 participants.

ETHICS AND DISSEMINATION

GO MOMs is centrally overseen by Vanderbilt University's Institutional Review Board and an Observational Study Monitoring Board appointed by National Institute of Diabetes and Digestive and Kidney Diseases. GO MOMs has potential to yield data that will improve understanding of hyperglycaemia in pregnancy, elucidate better approaches for early pregnancy GDM screening, and inform future clinical trials of early GDM treatment.

TRIAL REGISTRATION NUMBER

NCT04860336.

Integrated care of diabetes during pregnancy: a Qatari nationwide cohort

Background

Diabetes in pregnancy (DIP) is associated with adverse fetal and maternal outcomes. DIP is classified as either pre-existing or new-onset diabetes mellitus (DM), which is classified into gestational DM (GDM) and newly detected type 2 (N-T2D). All pregnant women in Qatar who are not known to have pre-existing DM are offered screening for DIP during the first antenatal care visit and after 24 weeks gestation. The study aims to report the DIP screening rates, the prevalence of DIP, and the impact of the universal screening program on adverse pregnancy outcomes.

Methods

This retrospective study included all women who gave birth in Hamad Medical Corporation (HMC) hospitals between 2019 and 2022. New-onset DIP was defined using the WHO-2013 criteria. The primary outcomes were the screening rates and the prevalence of DIP in Qatar. The secondary outcomes were the difference in preterm delivery, C-section, macrosomia, large for gestational age (LGA), small for gestational age (SGA), and intra-uterine fetal death (IUFD) between women with or without GDM.

Findings

We included 94,422 women who gave birth to 96,017 neonates (85.7%) out of 112,080 neonates born nationwide. The number of women with pre-existing diabetes was 2496 women. Of 91,926 eligible women, 77,372 (84.2%) were screened for DIP. The prevalence of GDM is 31.6% (95% CI: 31.3-32.0%); N-T2D is 2.2% (95% CI: 2.1-2.3%), and pre-existing Type 2 DM and Type 1 DM was 2.6% (95% CI: 0.8-3.0%) and 0.2% (0.19-0.25), respectively. Compared to the non-GDM group, women with GDM were older (30.8 ± 5.3 versus 29.7 ± 5.2 years, p < 0.001). After adjusting for age, women with GDM had lower risk of IUFD and SGA (0.63 [95% CI 0.50-0.80, p < 0.001], 0.88 [95% CI 0.84-0.92, p < 0.001] respectively) but higher risk of C-section and LFD (1.07 [95% CI 1.04-1.10, p < 0.001], 1.09 [95% CI 1.01-1.15, p = 0.01], respectively, compared to women with no-GDM.

Interpretation

Of the women eligible for screening, 84.2% were screened by the DIP program in Qatar. The prevalence of DIP in Qatar is 36.9%. Integrated care is critical for the screening and management of diabetes during pregnancy.

Fundings

The authors did not receive any funding for this project.

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.

Postpartum diabetes and cardiometabolic outcomes among Indian (South Asian) women with early Gestational diabetes mellitus: Insights from the CHIP-F study

Early GDM is associated with adverse pregnancy outcomes, however data on other outcomes are scarce. We evaluated women with early (n = 117) and classical (n = 412) GDM for long-term postpartum (median 32 months) glycemic and cardiometabolic outcomes and found a significantly higher prevalence of diabetes in the former [22.2 % vs. 12.6 %, p = 0.010].

Perinatal Outcomes of Diet Therapy in Gestational Diabetes Mellitus Diagnosed before 24 Gestational Weeks

To evaluate perinatal outcomes and risk factors for large for gestational age (LGA; birth weight over 90 percentile) in gestational diabetes diagnosed before 24 gestational weeks and treated with diet therapy alone until delivery (Diet Early gestational diabetes mellitus (Diet Early GDM)), we assessed the maternal characteristics and perinatal outcomes of patients with early GDM (n = 309) and normal glucose tolerance (NGT; n = 309) at Keio University Hospital. The gestational weight gain (GWG) expected at 40 weeks was significantly lower in the Diet Early GDM group than in the NGT group. The Diet Early GDM group exhibited a significantly lower incidence of low birth weight (<2500 g) and higher Apgar score at 5 min than the NGT group. Multiple logistic regression analysis revealed that the pre-pregnancy body mass index and GWG expected at 40 weeks were significantly associated with LGA for Diet Early GDM. No differences were observed in random plasma glucose levels in the first trimester, 75 g oral glucose tolerance test values, and initial increase or subsequent decrease between the two groups. Dietary early GDM did not exhibit a worse prognosis than NGT. To prevent LGA, it might be important to control maternal body weight not only during pregnancy but also before conception.

Lipids, apolipoproteins and gestational diabetes mellitus: a Mendelian randomization study

BACKGROUND

This study investigates the causal relationship between lipid traits and GDM in an effort to better understand the aetiology of GDM.

METHODS

Employing a two-sample Mendelian Randomization (MR) framework, we used Single Nucleotide Polymorphisms (SNPs) as instrumental variables to examine the impact of lipids and apolipoproteins on GDM. The research comprised univariable and multivariable MR analyses, with a prime focus on individual and combined effects of lipid-related traits. Statistical techniques included the fixed-effect inverse variance weighted (IVW) method and supplementary methods such as MR-Egger for comprehensive assessment.

RESULTS

Our findings revealed the following significant associations: apoA-I and HDL cholesterol were inversely correlated with GDM risk, while triglycerides showed a positive correlation. In multivariable analysis, apoA-I consistently exhibited a strong causal link with GDM, even after adjusting for other lipids and Body Mass Index (BMI).

CONCLUSION

The study demonstrates a significant causal relationship between apoA-I and GDM risk.

Cost-effectiveness of diagnosis and treatment of early gestational diabetes mellitus: economic evaluation of the TOBOGM study, an international multicenter randomized controlled trial

Background

A recently undertaken multicenter randomized controlled trial (RCT) "Treatment Of BOoking Gestational diabetes Mellitus" (TOBOGM: 2017-2022) found that the diagnosis and treatment of pregnant women with early gestational diabetes mellitus (GDM) improved pregnancy outcomes. Based on data from the trial, this study aimed to assess the cost-effectiveness of diagnosis and treatment of early GDM (from <20 weeks') among women with risk factors for hyperglycemia in pregnancy compared with usual care (no treatment until 24-28 weeks') from a healthcare perspective.

Methods

Participants' healthcare resource utilization data were collected from their self-reported questionnaires and hospital records, and valued using the unit costs obtained from standard Australian national sources. Costs were reported in US dollars ($) using the purchasing power parity (PPP) estimates to facilitate comparison of costs across countries. Intention-to-treat (ITT) principle was followed. Missing cost data were replaced using multiple imputations. Bootstrapping method was used to estimate the uncertainty around mean cost difference and cost-effectiveness results. Bootstrapped cost-effect pairs were used to plot the cost-effectiveness (CE) plane and cost-effectiveness acceptability curve (CEAC).

Findings

Diagnosis and treatment of early GDM was more effective and tended to be less costly, i.e., dominant (cost-saving) [-5.6% composite adverse pregnancy outcome (95% CI: -10.1%, -1.2%), -$1373 (95% CI: -$3,749, $642)] compared with usual care. Our findings were confirmed by both the CE plane (88% of the bootstrapped cost-effect pairs fall in the south-west quadrant), and CEAC (the probability of the intervention being cost-effective ranged from 84% at a willingness-to-pay (WTP) threshold value of $10,000-99% at a WTP threshold value of $100,000 per composite adverse pregnancy outcome prevented). Sub-group analyses demonstrated that diagnosis and treatment of early GDM among women in the higher glycemic range (fasting blood glucose 95-109 mg/dl [5.3-6.0 mmol/L], 1-h blood glucose ≥191 mg/dl [10.6 mmol/L] and/or 2-h blood glucose 162-199 mg/dl [9.0-11.0 mmol/L]) was more effective and less costly (dominant) [-7.8% composite adverse pregnancy outcome (95% CI: -14.6%, -0.9%), -$2795 (95% CI: -$6,638, -$533)]; the intervention was more effective and tended to be less costly [-8.9% composite adverse pregnancy outcome (95% CI: -15.1%, -2.6%), -$5548 (95% CI: -$16,740, $1547)] among women diagnosed before 14 weeks' gestation as well.

Interpretation

Our findings highlight the potential health and economic benefits from the diagnosis and treatment of early GDM among women with risk factors for hyperglycemia in pregnancy and supports its implementation. Long-term follow-up studies are recommended as a key future area of research to assess the potential long-term health benefits and economic consequences of the intervention.

Funding

National Health and Medical Research Council (grants 1104231 and 2009326), Region O¨rebro Research Committee (grants Dnr OLL-970566 and OLL-942177), Medical Scientific Fund of the Mayor of Vienna (project 15,205 and project 23,026), South Western Sydney Local Health District Academic Unit (grant 2016), and Western Sydney University Ainsworth Trust Grant (2019).

Butyrate and iso-butyrate: a new perspective on nutrition prevention of gestational diabetes mellitus

BACKGROUND

Dietary imbalance, such as a lower proportion of complex carbohydrates and a higher protein diet, may contribute to gestational diabetes mellitus (GDM) risks through their metabolisms. However, there is a lack of knowledge regarding the association between butyrate, iso-butyrate, and GDM, which are metabolisms of the two primary nutrients above. This study aimed to clarify the association of butyrate and iso-butyrate with GDM.

METHODS

A nested case-control study was conducted based on the Beijing Birth Cohort Study (BBCS) from 2017 to 2018. Totally, 99 singleton women were involved (GDM: n = 49, control: n = 50). All participants provided blood samples twice (in their first and second trimesters). Gas chromatography-mass spectrometry (GC-MS) was used for butyrate and iso-butyrate detection. Unconditional logistic regression and receiver operating characteristic (ROC) curve analysis were used for statistical analysis.

RESULTS

The results showed that butyrate in the first trimester was negatively correlated with GDM (odds ratio (OR): 0.00, 95% confidential interval (CI): 0.00-0.21, P = 0.008), and iso-butyrate in the second trimester was positively related to GDM (OR: 627.68, 95% CI: 40.51-9724.56, P < 0.001). The ratio (butyrate/iso-butyrate) was negatively associated with GDM, both in the first trimester (OR: 0.00, 95%CI: 0.00-0.05, P < 0.001) and in the second trimester (OR: 0.52, 95% CI: 0.34-0.80, P = 0.003). The area under the curve (AUC) using the ratio in the first trimester combined with clinical risk factors achieved 0.89 (95% CI: 0.83-0.95). Iso-butyrate in the second trimester combined with clinical risk factors achieved an AUC of 0.97 (95% CI: 0.92-1.00).

CONCLUSIONS

High iso-butyrate and low butyrate levels may be associated with an increased risk of GDM. As they are produced through dietary nutrient formation by gut microbiota, further studies on the association of dietary intake and butyrate or iso-butyrate concentration in plasma may help find a novel approach to nutritional intervention for GDM.

The first International Association of Diabetes and Pregnancy Study Groups summit on the diagnosis of gestational diabetes in early pregnancy: TOBOGM Summit Report

The first International Association of Diabetes and Pregnancy Study Groups Summit on the diagnosis of gestational diabetes in early pregnancy (Treatment of Booking Gestational Diabetes Mellitus (TOBOGM) Summit) was held on the 17 November 2022 in Sydney, Australia. It sought to use the TOBOGM trial findings to scope the issues involved with early screening, to inform future discussions over possible approaches for diagnosing gestational diabetes mellitus (GDM) in early pregnancy. Most delegates supported testing for early GDM using a one-step 75 g oral glucose tolerance test approach with Canadian Diabetes Association criteria preferred, but highlighted the importance of considering resources, cost, consumer perspectives and equity in translating TOBOGM results into a clinical approach to screening for, and diagnosing, early GDM.

Neonatal outcomes according to different glucose threshold values in gestational diabetes: a register-based study

BACKGROUND

Mild hyperglycaemia is associated with increased birth weight but association with other neonatal outcomes is controversial. We aimed to study neonatal outcomes in untreated mild hyperglycaemia using different oral glucose tolerance test (OGTT) thresholds.

METHODS

This register-based study included all (n = 4,939) singleton pregnant women participating a 75 g 2-h OGTT in six delivery hospitals in Finland in 2009. Finnish diagnostic cut-offs for GDM were fasting ≥ 5.3, 1 h ≥ 10.0 or 2-h glucose ≥ 8.6 mmol/L. Women who did not meet these criteria but met the International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria (fasting 5.1-5.2 mmol/L and/or 2-h glucose 8.5 mmol/L, n = 509) or the National Institute for Health and Clinical Excellence (NICE) criteria (2-h glucose 7.8-8.5 mmol/L, n = 166) were considered as mild untreated hyperglycaemia. Women who met both the Finnish criteria and the IADPSG or the NICE criteria were considered as treated GDM groups (n = 1292 and n = 612, respectively). Controls were normoglycaemic according to all criteria (fasting glucose < 5.1 mmol/L, 1-h glucose < 10.0 mmol/L and 2-h glucose < 8.5 mmol/L, n = 3031). Untreated mild hyperglycemia groups were compared to controls and treated GDM groups. The primary outcome - a composite of adverse neonatal outcomes, including neonatal hypoglycaemia, hyperbilirubinaemia, birth trauma or perinatal mortality - was analysed using multivariate logistic regression.

RESULTS

The risk for the adverse neonatal outcome in untreated mild hyperglycemia was not increased compared to controls (adjusted odds ratio [aOR]: 1.01, 95% confidence interval [CI]: 0.71-1.44, using the IADPSG criteria; aOR: 1.05, 95% CI: 0.60-1.85, using the NICE criteria). The risk was lower compared to the treated IADPSG (aOR 0.38, 95% CI 0.27-0.53) or the treated NICE group (aOR 0.32, 95% CI 0.18-0.57).

DISCUSSION

The risk of adverse neonatal outcomes was not increased in mild untreated hyperglycaemia compared to normoglycaemic controls and was lower than in the treated GDM groups. The OGTT cut-offs of 5.3 mmol/L at fasting and 8.6 mmol/L at 2 h seem to sufficiently identify clinically relevant GDM, without excluding neonates with a risk of adverse outcomes.

Gestational diabetes mellitus is associated with in vivo platelet activation and platelet hyperreactivity

BACKGROUND

Gestational diabetes mellitus is associated with obstetrical and long-term cardiovascular complications. Although platelet hyperresponsiveness in type-2 diabetes mellitus has been well characterized and has been shown to play a crucial role in cardiovascular complications, this aspect has been little studied in gestational diabetes mellitus.

OBJECTIVE

We aimed to evaluate platelet reactivity, in vivo platelet activation, and endothelial function in gestational diabetes mellitus in comparison with normal pregnancy.

STUDY DESIGN

This was a prospective, case-control study of 23 women with gestational diabetes mellitus and 23 healthy pregnant women who were studied at 26 to 28 and 34 to 36 weeks of gestation and at 8 weeks postpartum. Platelet reactivity and in vivo platelet activation, including light transmission aggregometry, PFA-100, platelet activation antigen expression, platelet adhesion under flow, platelet nitric oxide and reactive oxygen species production, and endothelial dysfunction markers, were assessed.

RESULTS

The study of platelet function showed a condition of platelet hyperreactivity in cases with gestational diabetes mellitus when compared with healthy pregnant women at enrollment, which was further enhanced at the end of pregnancy and tended to decrease 2 months after delivery, although it still remained higher in gestational diabetes mellitus. In vivo platelet activation was also evident in gestational diabetes mellitus, especially at the end of pregnancy, in part persisting up to 8 weeks after delivery. Finally, women with gestational diabetes mellitus showed defective platelet nitric oxide production and endothelial dysfunction when compared with healthy pregnancies.

CONCLUSION

Our data showed that gestational diabetes mellitus generates a condition of platelet hyperreactivity that in part persists up to 2 months after delivery. Impaired platelet sensitivity to nitric oxide and reduced platelet and endothelial nitric oxide production may contribute to the platelet hyperreactivity condition. Platelet hyperreactivity may play a role in the long-term cardiovascular complications of gestational diabetes mellitus women.

Routine screening for gestational diabetes: a review

PURPOSE OF REVIEW

Rates of gestational diabetes mellitus (GDM) throughout the world continue to increase associated with the increasing rates of obesity. Given this epidemiologic burden, the importance of proper screening, diagnosis, and management cannot be understated. This review focuses on the current screening guidelines utilized throughout the world and new data recently published regarding the most optimal screening techniques and future directions for research.

RECENT FINDINGS

Despite unanimous opinion that GDM warrants screening, the optimal screening regimen remains controversial. Notably, in the United States per the consensus recommendation by the American College of Obstetrics and Gynecology and the Society for Maternal-Fetal Medicine, a 2-step screening approach is often used. Recently, there have been multiple studies published that have compared the 1-step and 2-step screening process with respect to GDM incidence and perinatal outcomes. These new findings are summarized below.

SUMMARY

Utilization of the 1-step screening as opposed to the 2-step screening results in an increased diagnosis of GDM without significant population level benefit in outcomes. However, these studies remain underpowered to allow for meaningful comparison of outcomes in those diagnosed with GDM.

Despite treatment, HbA1c ≥ 37 mmol/mol in the first trimester is associated with premature delivery among South Asian women with gestational diabetes mellitus: a retrospective cohort study

PURPOSE

To examine the effects of first-trimester HbA1c (HbA1c-FT) ≥ 37 mmol/mol on preterm birth (PTB) and large-for-gestational-age (LGA) babies in a retrospective cohort of South Asian pregnant women with gestational diabetes (GDM).

METHODS

The cohort (n = 686) was separated into two groups based on HbA1c-FT values: Group A (n = 97) and Group B (n = 589), with values of 37-46 mmol/mol (5.5-6.4%) and < 37 mmol/mol (5.5%), respectively. HbA1c-FT's independent influence on PTB and LGA babies was examined using multivariable logistic regression in groups A and B women. The reference group (Group C) included 2031 non-GDM women with HbA1c-FT < 37 mmol/mol (< 5.5%). The effects of HbA1c-FT on PTB and LGA babies in obese women in Groups A, B, and C (designated as A-ob, B-ob, and C-ob, respectively) were re-analyzed using multivariable logistic regression.

RESULTS

Group A GDM women with greater HbA1c-FT had a higher risk for PTB (aOR:1.86, 95% CI:1.10-3.14) but not LGA babies (aOR:1.13, 95%: 0.70-1.83). The risk of PTB was higher for obese women in Group A-ob: aOR 3.28 [95% CI 1.68-6.39]. However, GDM women with normal HbA1c-FT exhibited no elevated risk for PTB: Groups B and B-ob had aORs of 1.30 (95% CI 0.86-1.98) and 1.28 (95% CI 0.88-1.85) respectively.

CONCLUSIONS

South Asian GDM women with prediabetic HbA1c FT; 37-46 mmol/mol (5.5-6.4%) are more likely to deliver preterm babies despite treatment, while the risk for LGA babies was the same as non-GDM women.

Glucose tolerance test with a single abnormal value as a predictor of type 2 diabetes mellitus: a multicenter retrospective study

Clinical implication of a single abnormal value (SAV) in the 100 g oral glucose tolerance test during pregnancy has not been established. We aimed to evaluate the risk of postpartum type 2 diabetes mellitus (T2DM) and investigate adverse pregnancy outcomes in women with SAV, using a retrospective database, from seven medical centers of Korea. Based on the Carpenter-Coustan criteria using two-step approach, pregnancy and postpartum outcomes were compared, among normoglycemic, SAV, and gestational diabetes mellitus (GDM) groups. Among 9353 women, 342 (3.66%) and 418(4.47%) women were included in SAV and GDM groups, respectively. SAV and GDM groups showed significantly higher rates of postpartum T2DM than normoglycemic group (7.60%, 14.83%, and 1.82%, respectively, p < 0.001). And SAV group showed significantly higher rates of pregnancy associated hypertension, preterm birth, and neonatal hypoglycemia and sepsis, compared to normoglycemic group (neonatal sepsis, p = 0.008; the others, p < 0.001). In multivariate analysis, postpartum T2DM was associated with SAV, GDM (with/without insulin), nulliparity, pre-pregnancy BMI, chronic hypertension, hyperlipidemia, and DM family history. A scoring model to predict postpartum T2DM within 5 years, achieved an area under the curve of 0.74. This study demonstrated that not only GDM, but also SAV is a significant risk factor for postpartum T2DM.

Future clinical prospects of C-peptide testing in the early diagnosis of gestational diabetes

Gestational diabetes is typically diagnosed in the late second or third trimester of pregnancy. It is one of the most common metabolic disorders among expectant mothers, with potential serious short- and long-term complications for both maternal and offspring health. C-peptide is secreted from pancreatic beta-cells into circulation in equimolar amounts with insulin. It is a useful biomarker to estimate the beta-cell function because it undergoes negligible hepatic clearance and consequently it has a longer half-life compared to insulin. Pregnancy induces increased insulin resistance due to physiological changes in hormonal and metabolic homeostasis. Inadequate compensation by islet beta-cells results in hyperglycemia. The standard oral glucose tolerance test at 24-28 wk of gestation sets the diagnosis. Accumulated evidence from prospective studies indicates a link between early pregnancy C-peptide levels and the risk of subsequent gestational diabetes. Elevated C-peptide levels and surrogate glycemic indices at the beginning of pregnancy could prompt appropriate strategies for secondary prevention.

Gestational diabetes mellitus, hypertension, and dyslipidemia as the risk factors of preeclampsia

Gestational diabetes mellitus (GDM) is a known risk factor for gestational hypertension which further progress toward conditions like proteinuria, dyslipidemia, thrombocytopenia, pulmonary edema leading to Preeclampsia (PE). Pregnancy can be a challenging time for many women, especially those diagnosed with GDM and PE. Thus, the current prospective study investigates the association of OGTT glucose levels with systolic and diastolic blood pressure and lipid profile parameters in pregnant women diagnosed with GDM and PE. A total of 140 pregnant women were stratified into GDM (n = 50), PE (n = 40) and controls (n = 50). Two hour 75 g oral glucose tolerance test (OGTT) was performed for screening GDM. Biochemical parameters analysis of OGTT, total cholesterol (TC), triglyceride (Tg), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C), urinary albumin and creatinine were tested to find urinary albumin creatinine ratio (uACR). Statistical analysis was performed using ANOVA followed by post hoc test and regression analysis. Among the studied groups, GDM and PE groups showed no significant difference in age and increased BMI. Increased 2 h OGTT & TC in GDM group; elevated uACR, systolic/diastolic blood pressure, Tg, HDL-C, LDL-C in PE group was observed and differ significantly (p < 0.0001) with other groups. A significant positive effect of 2 h OGTT was observed on blood pressure (R2: GDM = 0.85, PE = 0.71) and lipid profile determinants (R2: GDM = 0.85, PE = 0.33) at p < 0.0001. The current study concludes that glucose intolerance during the later weeks of pregnancy is associated with gestational hypertension and hyperlipidemia as a risk factor for PE. Further research is needed for a detailed assessment of maternal glucose metabolism at various pregnancy stages, including the use of more sensitive markers such as C-peptide and their relation to pregnancy-related hypertensive disorders.

Maternal and neonatal outcomes according to the timing of diagnosis of hyperglycaemia in pregnancy: a nationwide cross-sectional study of 695,912 deliveries in France in 2018

AIMS/HYPOTHESIS

We aimed to assess maternal-fetal outcomes according to various subtypes of hyperglycaemia in pregnancy.

METHODS

We used data from the French National Health Data System (Système National des Données de Santé), which links individual data from the hospital discharge database and the French National Health Insurance information system. We included all deliveries after 22 gestational weeks (GW) in women without pre-existing diabetes recorded in 2018. Women with hyperglycaemia were classified as having overt diabetes in pregnancy or gestational diabetes mellitus (GDM), then categorised into three subgroups according to their gestational age at the time of GDM diagnosis: before 22 GW (GDM<22); between 22 and 30 GW (GDM22-30); and after 30 GW (GDM>30). Adjusted prevalence ratios (95% CI) for the outcomes were estimated after adjusting for maternal age, gestational age and socioeconomic status. Due to the multiple tests, we considered an association to be statistically significant according to the Holm-Bonferroni procedure. To take into account the potential immortal time bias, we performed analyses on deliveries at ≥31 GW and deliveries at ≥37 GW.

RESULTS

The study population of 695,912 women who gave birth in 2018 included 84,705 women (12.2%) with hyperglycaemia in pregnancy: overt diabetes in pregnancy, 0.4%; GDM<22, 36.8%; GDM22-30, 52.4%; and GDM>30, 10.4%. The following outcomes were statistically significant after Holm-Bonferroni adjustment for deliveries at ≥31 GW using GDM22-30 as the reference. Caesarean sections (1.54 [1.39, 1.72]), large-for-gestational-age (LGA) infants (2.00 [1.72, 2.32]), Erb's palsy or clavicle fracture (6.38 [2.42, 16.8]), preterm birth (1.84 [1.41, 2.40]) and neonatal hypoglycaemia (1.98 [1.39, 2.83]) were more frequent in women with overt diabetes. Similarly, LGA infants (1.10 [1.06, 1.14]) and Erb's palsy or clavicle fracture (1.55 [1.22, 1.99]) were more frequent in GDM<22. LGA infants (1.44 [1.37, 1.52]) were more frequent in GDM>30. Finally, women without hyperglycaemia in pregnancy were less likely to have preeclampsia or eclampsia (0.74 [0.69, 0.79]), Caesarean section (0.80 [0.79, 0.82]), pregnancy and postpartum haemorrhage (0.93 [0.89, 0.96]), LGA neonate (0.67 [0.65, 0.69]), premature neonate (0.80 [0.77, 0.83]) and neonate with neonatal hypoglycaemia (0.73 [0.66, 0.82]). Overall, the results were similar for deliveries at ≥37 GW. Although the estimation of the adjusted prevalence ratio of perinatal death was five times higher (5.06 [1.87, 13.7]) for women with overt diabetes, this result was non-significant after Holm-Bonferroni adjustment.

CONCLUSIONS/INTERPRETATION

Compared with GDM22-30, overt diabetes, GDM<22 and, to a lesser extent, GDM>30 were associated with poorer maternal-fetal outcomes.

First-trimester HbA1c in relation to plasma glucose concentrations in an oral glucose tolerance test at 12 to 16 weeks' gestation-a population-based study

BACKGROUND

Early-onset GDM often requires pharmacological treatment and is associated with adverse perinatal outcomes, but data is insufficient regarding the best methods to identify high-risk women requiring early GDM screening. The aim of this study was to analyze the diagnostic accuracy of HbA1c in the prediction of (1) plasma glucose concentrations > 90th percentile in an oral glucose tolerance test (OGTT) at 12-16 weeks' gestation; and (2) pharmacologically treated early- or late-onset GDM.

METHODS

HbA1c was measured at 8-14 weeks' gestation in a population-based cohort of 1394 Finnish women recruited for the Early Diagnosis of Diabetes in Pregnancy (EDDIE) study between 3/2013 and 12/2016. Information on maternal risk factors were collected at recruitment. Subsequently, a 2-hour 75 g OGTT was performed at 12-16 weeks' gestation (OGTT1), and if normal, repeated at 24-28 weeks' gestation (OGTT2). Early- and late-onset GDM were diagnosed using the same nationally endorsed cut-offs for fasting, 1 h- and 2 h-plasma glucose: ≥5.3, ≥ 10.0mmol/l, and/or ≥ 8.6mmol/l, respectively. In total, 52/1394 (3.7%) women required metformin or insulin treatment for GDM, including 39 women with early-onset GDM diagnosed at OGTT1 and 13 women with late-onset GDM diagnosed at OGTT2.

RESULTS

Maternal early-pregnancy HbA1c ≥ 35mmol/mol (≥ 5.4%) was the best cut-off to predict fasting or post-load plasma glucose > 90th percentile in OGTT1, but its diagnostic accuracy was low [AUC (95% CI) 0.65 (0.62 to 0.69), sensitivity 0.55 (0.49 to 0.60) and specificity 0.67 (0.64 to 0.70)] both alone and in combination with other maternal risk factors. However, HbA1c ≥ 35mmol/mol correlated positively with plasma glucose concentrations at all time points of OGTT1 and predicted pharmacologically treated GDM diagnosed at OGTT1 or OGTT2; AUC (95% CI) 0.75 (0.68 to 0.81), sensitivity 0.75 (0.61 to 0.86), specificity 0.64 (0.61 to 0.66).

CONCLUSIONS

In our population-based cohort, early-pregnancy HbA1c ≥ 35mmol/mol was positively associated with fasting and post-load plasma glucose concentrations in an OGTT at 12-16 weeks' gestation and predicted pharmacologically-treated early- and late-onset GDM, suggesting potential utility in first-trimester identification of women at high risk of severe GDM subtypes.

Promoting healthy eating in early pregnancy in individuals at risk of gestational diabetes mellitus: does it improve glucose homeostasis? A study protocol for a randomized control trial

Background

Healthy eating during pregnancy has favorable effects on glycemic control and is associated with a lower risk of gestational diabetes mellitus (GDM). According to Diabetes Canada, there is a need for an effective and acceptable intervention that could improve glucose homeostasis and support pregnant individuals at risk for GDM.

Aims

This unicentric randomized controlled trial (RCT) aims to evaluate the effects of a nutritional intervention initiated early in pregnancy, on glucose homeostasis in 150 pregnant individuals at risk for GDM, compared to usual care.

Methods

Population: 150 pregnant individuals ≥18 years old, at ≤14 weeks of pregnancy, and presenting ≥1 risk factor for GDM according to Diabetes Canada guidelines. Intervention: The nutritional intervention initiated in the first trimester is based on the health behavior change theory during pregnancy and on Canada's Food Guide recommendations. It includes (1) four individual counseling sessions with a registered dietitian using motivational interviewing (12, 18, 24, and 30 weeks), with post-interview phone call follow-ups, aiming to develop and achieve S.M.A.R.T. nutritional objectives (specific, measurable, attainable, relevant, and time-bound); (2) 10 informative video clips on healthy eating during pregnancy developed by our team and based on national guidelines, and (3) a virtual support community via a Facebook group. Control: Usual prenatal care. Protocol: This RCT includes three on-site visits (10-14, 24-26, and 34-36 weeks) during which a 2-h oral glucose tolerance test is done and blood samples are taken. At each trimester and 3 months postpartum, participants complete web-based questionnaires, including three validated 24-h dietary recalls to assess their diet quality using the Healthy Eating Food Index 2019. Primary outcome: Difference in the change in fasting blood glucose (from the first to the third trimester) between groups. This study has been approved by the Ethics Committee of the Centre de recherche du CHU de Québec-Université Laval.

Discussion

This RCT will determine whether a nutritional intervention initiated early in pregnancy can improve glucose homeostasis in individuals at risk for GDM and inform Canadian stakeholders on improving care trajectories and policies for pregnant individuals at risk for GDM.

Clinical trial registration

https://clinicaltrials.gov/study/NCT05299502, NCT05299502.

2. Diagnosis and Classification of Diabetes: Standards of Care in Diabetes-2024

The American Diabetes Association (ADA) "Standards of Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, an interprofessional expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations and a full list of Professional Practice Committee members, please refer to Introduction and Methodology. Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Metformin Plus Insulin for Preexisting Diabetes or Gestational Diabetes in Early Pregnancy: The MOMPOD Randomized Clinical Trial

Importance

Insulin is recommended for pregnant persons with preexisting type 2 diabetes or diabetes diagnosed early in pregnancy. The addition of metformin to insulin may improve neonatal outcomes.

Objective

To estimate the effect of metformin added to insulin for preexisting type 2 or diabetes diagnosed early in pregnancy on a composite adverse neonatal outcome.

Design, Setting, and Participants

This randomized clinical trial in 17 US centers enrolled pregnant adults aged 18 to 45 years with preexisting type 2 diabetes or diabetes diagnosed prior to 23 weeks' gestation between April 2019 and November 2021. Each participant was treated with insulin and was assigned to add either metformin or placebo. Follow-up was completed in May 2022.

Intervention

Metformin 1000 mg or placebo orally twice per day from enrollment (11 weeks -<23 weeks) through delivery.

Main Outcome and Measures

The primary outcome was a composite of neonatal complications including perinatal death, preterm birth, large or small for gestational age, and hyperbilirubinemia requiring phototherapy. Prespecified secondary outcomes included maternal hypoglycemia and neonatal fat mass at birth, and prespecified subgroup analyses by maternal body mass index less than 30 vs 30 or greater and those with preexisting vs diabetes early in pregnancy.

Results

Of the 831 participants randomized, 794 took at least 1 dose of the study agent and were included in the primary analysis (397 in the placebo group and 397 in the metformin group). Participants' mean (SD) age was 32.9 (5.6) years; 234 (29%) were Black, and 412 (52%) were Hispanic. The composite adverse neonatal outcome occurred in 280 (71%) of the metformin group and in 292 (74%) of the placebo group (adjusted odds ratio, 0.86 [95% CI 0.63-1.19]). The most commonly occurring events in the primary outcome in both groups were preterm birth, neonatal hypoglycemia, and delivery of a large-for-gestational-age infant. The study was halted at 75% accrual for futility in detecting a significant difference in the primary outcome. Prespecified secondary outcomes and subgroup analyses were similar between groups. Of individual components of the composite adverse neonatal outcome, metformin-exposed neonates had lower odds to be large for gestational age (adjusted odds ratio, 0.63 [95% CI, 0.46-0.86]) when compared with the placebo group.

Conclusions and Relevance

Using metformin plus insulin to treat preexisting type 2 or gestational diabetes diagnosed early in pregnancy did not reduce a composite neonatal adverse outcome. The effect of reduction in odds of a large-for-gestational-age infant observed after adding metformin to insulin warrants further investigation.

Trial Registration

ClinicalTrials.gov Identifier: NCT02932475.

Various screening and diagnosis approaches for gestational diabetes mellitus and adverse pregnancy outcomes: a secondary analysis of a randomized non-inferiority field trial

INTRODUCTION

We evaluate which screening and diagnostic approach resulted in the greatest reduction in adverse pregnancy outcomes due to increased treatment.

RESEARCH DESIGN AND METHODS

This study presents a secondary analysis of a randomized community non-inferiority trial conducted among pregnant women participating in the GULF Study in Iran. A total of 35 430 pregnant women were randomly assigned to one of the five prespecified gestational diabetes mellitus (GDM) screening protocols. The screening methods included fasting plasma glucose (FPG) in the first trimester and either a one-step or a two-step screening method in the second trimester of pregnancy. According to the results, participants were classified into 6 groups (1) First-trimester FPG: 100-126 mg/dL, GDM diagnosed at first trimester; (2) First trimester FPG: 92-99.9 mg/dL, GDM diagnosed at first trimester; (3) First trimester FPG: 92-99.9 mg/dL, GDM diagnosed at second trimester; (4) First trimester FPG: 92-99.9 mg/dL, healthy at second trimester; (5) First trimester FPG<92 mg/dL, GDM diagnosed at second trimester; (6) First trimester FPG<92 mg/dL, healthy at second trimester. For our analysis, we initially used group 6, as the reference and repeated the analysis using group 2, as the reference group. The main outcome of the study was major adverse maternal and neonatal outcomes.

RESULTS

Macrosomia and primary caesarean section occurred in 9.8% and 21.0% in group 1, 7.8% and 19.8% in group 2, 5.4% and 18.6% in group 3, 6.6% and 21.5% in group 4, 8.3% and 24.0% in group 5, and 5.4% and 20.0% in group 6, respectively. Compared with group 6 as the reference, there was a significant increase in the adjusted risk of neonatal intensive care unit (NICU) admission in groups 1, 3, and 5 and an increased risk of macrosomia in groups 1, 2, and 5. Compared with group 2 as the reference, there was a significant decrease in the adjusted risk of macrosomia in group 3, a decreased risk of NICU admission in group 6, and an increased risk of hyperglycemia in group 3.

CONCLUSIONS

We conclude that screening approaches for GDM reduced the risk of adverse pregnancy outcomes to the same or near the same risk level of healthy pregnant women, except for the risk of NICU admission that increased significantly in groups diagnosed with GDM compared with healthy pregnant women. Individuals with slight increase in FPG (92-100 mg/dL) at first trimester, who were diagnosed as GDM, had an even increased risk of macrosomia in comparison to those group of women with FPG 92-100 mg/dL in the first trimester, who were not diagnosed with GDM, and developed GDM in second trimester TRIAL REGISTRATION: IRCT138707081281N1 (registered: February 15, 2017).

Serum Vaspin Levels in Gestational Diabetes Mellitus: A Meta-Analysis

The objective of this study was to evaluate the potential relationship between serum vaspin levels and gestational diabetes mellitus (GDM). The PubMed, EBSCO, Web of Science, the Cochrane Library, and the China National Knowledge Infrastructure (CNKI) database were searched for articles published before December 2022. The publication language was restricted to English and Chinese. A meta-analysis was conducted by combining all studies that met the inclusion and exclusion criteria. Twenty-two studies (1990 women with GDM and 1597 pregnant women without GDM) were ultimately included in this meta-analysis. The meta-analysis showed that the serum vaspin levels are significantly higher in GDM compared with the controls (standardized mean difference: 0.720, 95% confidence interval: 0.440-1.000, Z = 5.041, P < 0.001). Subgroup analyses by stage of pregnancy and body mass index showed results similar to the overall outcome. No publication bias was identified, and the sensitivity analysis confirmed the robustness of the final result. Our results show that the serum vaspin levels are significantly higher in GDM. These findings suggest that high vaspin concentration is closely related to GDM and the serum vaspin levels might be a potential biomarker to indicate risk of GDM, more randomized control trials comparing the expression levels of vaspin between early and standard diagnosis of GDM are needed to strengthen our findings.

Employing fasting plasma glucose to safely limit the use of oral glucose tolerance tests in pregnancy: a pooled analysis of four Norwegian studies

Background/objective

There is no international consensus about the optimal approach to screening and diagnosis of gestational diabetes mellitus (GDM). Fasting plasma glucose (FPG) has been proposed as an alternative universal screening test to simplify the diagnosis of GDM. We investigate the ability of the FPG to predict a 2-hour glucose value below the cut-off for GDM, thereby "ruling out" the necessity of a full OGTT and assess the proportion of GDM-related complications associated with the identified FPG level.

Materials and methods

This study included secondary data from four Norwegian pregnancy cohorts (2002-2013), encompassing 2960 women universally screened with late mid-pregnancy 75g OGTT measuring FPG and 2-hour glucose. For a range of FPG thresholds, we calculated sensitivity to predict elevated 2-hour glucose, number of OGTTs needed and percentage of GDM cases missed, applying modified World Health Organization (WHO) 2013 criteria (2013WHO) and 2017 Norwegian criteria (2017Norwegian). We analyzed pregnancy outcomes for women above and below our selected threshold.

Results

The prevalence of GDM was 16.6% (2013WHO) and 10.1% (2017Norwegian). A FPG threshold of 4.7 mmol/L had a sensitivity of 76% (2013WHO) and 80% (2017Norwegian) for detecting elevated 2-hour glucose, with few missed GDM cases (2.0% of those ruled out and 7.5% of all GDM cases for 2013WHO, and 1.1% of those ruled out and 7% of all GDM cases for 2017Norwegian). When excluding women with FPG <4.7mmol/l and those with GDM based on FPG, only 24% (2013WHO) and 29% (2017Norwegian) would require OGTT. Women with FPG <4.7mmol/l, including missed GDM cases, had low risk of large-for-gestational-age newborns, cesarean section and operative vaginal delivery.

Conclusion

A FPG threshold of 4.7mmol/l as a first step when screening for GDM could potentially eliminate the need for OGTT in 70-77% of pregnancies. Women with FPG below this threshold appear to carry low risk of GDM-associated adverse pregnancy outcomes.

Free triiodothyronine (FT3)-to-free thyroxine (FT4) ratio identified as a risk factor for gestational diabetes in euthyroid pregnant women: insights from a Chinese population cohort study

Background

To explore the association between thyroid hormones and gestational diabetes mellitus in euthyroid pregnant women, with the aim of preventing the occurrence of gestational diabetes mellitus.

Methods

In this prospective study, a total of 1222 euthyroid pregnant women in their first trimester were recruited at Peking University International Hospital between December 2017 and March 2019. These participants underwent an oral glucose tolerance test during the 24-28 weeks of gestation.

Results

During early pregnancy, the gestational diabetes mellitus group displayed lower levels of free thyroxine when compared to the non-gestational diabetes mellitus group. Additionally, the ratio of free triiodothyronine to free thyroxine in the gestational diabetes mellitus group during early pregnancy was significantly higher (p<0.05). The ratio of free triiodothyronine to free thyroxine during early pregnancy showed a positive correlation with blood glucose levels at 0, 60, and 120 min both before and after glucose loading (all p<0.05). During early pregnancy, there was a negative relationship between free thyroxine levels and fasting blood glucose. The free triiodothyronine levels were positively correlated to blood glucose levels at 120 min following glucose loading (all p<0.05).

Conclusion

The ratio of free triiodothyronine-to-free thyroxine is an independent risk factor for gestational diabetes mellitus and has the potential to be a predictor for gestational diabetes mellitus in euthyroid pregnant women.

The CHANGED Score-A New Tool for the Prediction of Insulin Dependency in Gestational Diabetes

Gestational diabetes (GDM) is a frequent complication during pregnancy. We aimed to develop a score to predict future insulin dependency in gestational diabetes (GDM). Data from 1611 patients from Charité Berlins gestational diabetes clinic from 2015 to 2022 were utilized. A stepwise backwards regression, including patient characteristics obtained at the initial presentation, was performed. Predictors examined included age, fasting blood glucose level, blood glucose levels one and two hours after oral glucose tolerance test, pre-pregnancy BMI, number of previous pregnancies and births, and fetal sex. The ideal cutoff value between high and low risk for insulin dependency was assessed and the score was internally validated. There were 1249 (77.5%) women diagnosed with dietary GDM and 362 (22.5%) were diagnosed with insulin-dependent GDM. The CHarité AssessmeNt of GEstational Diabetes (CHANGED) Score achieved an area under the curve of 0.77 (95% confidence interval 0.75-0.80; 0.75 in internal validation). The optimal cutoff value was calculated at a score value of 9 (72% sensitivity, 69% specificity). We developed an easily applicable tool to accurately predict insulin dependency in gestational diabetes. The CHANGED Score is routinely available and can potentially improve maternal and fetal outcomes.

Roadmap to the Effective Use of Continuous Glucose Monitoring in Pregnancy

The landscape for managing type 1 diabetes during pregnancy has been transformed by increasing use of continuous glucose monitoring (CGM). Women are aiming for pregnancy-specific glucose targets or 70% time in range for pregnancy (TIRp; 63-140 mg/dL) as soon as possible, knowing that every extra 5% TIRp has benefits for reducing the risks of complications in their babies. Ongoing monitoring of maternal A1C (at pregnancy confirmation and at 20, 28, and 36 weeks' gestation) remains useful. Intensification of glycemic management and instruction in using CGM (if not already used) is recommended for individuals with an A1C >6.0% after 20 weeks. A better understanding of CGM-documented glycemic changes throughout pregnancy is needed to inform future management of gestational diabetes and pregnancy in people with type 2 diabetes. Research regarding overcoming barriers to CGM use and optimal TIRp targets for pregnant individuals with type 2 diabetes from diverse racial/ethnic groups is urgently needed.

Nutrients as Risk Factors and Treatments for Gestational Diabetes

Gestational diabetes (GDM), traditionally defined as any form of glucose intolerance first detected in pregnancy [...].

Sensitivity, specificity, and diagnostic accuracy of WHO 2013 criteria for diagnosis of gestational diabetes mellitus in low risk early pregnancies: international, prospective, multicentre cohort study

Objective

To evaluate the predictability of gestational diabetes mellitus wth a 75 g oral glucose tolerance test (OGTT) in early pregnancy, based on the 2013 criteria of the World Health Organization, and to test newly proposed cut-off values.

Design

International, prospective, multicentre cohort study.

Setting

Six university or cantonal departments in Austria, Germany, and Switzerland, from 1 May 2016 to 31 January 2019.

Participants

Low risk cohort of 829 participants aged 18-45 years with singleton pregnancies attending first trimester screening and consenting to have an early 75 g OGTT at 12-15 weeks of gestation. Participants and healthcare providers were blinded to the results.

Main outcome measures

Fasting, one hour, and two hour plasma glucose concentrations after an early 75 g OGTT (12-15 weeks of gestation) and a late 75 g OGTT (24-28 weeks of gestation).

Results

Of 636 participants, 74 (12%) developed gestational diabetes mellitus, according to World Health Organization 2013 criteria, at 24-28 weeks of gestation. Applying WHO 2013 criteria to the early OGTT with at least one abnormal value gave a low sensitivity of 0.35 (95% confidence interval 0.24 to 0.47), high specificity of 0.96 (0.95 to 0.98), positive predictive value of 0.57 (0.41 to 0.71), negative predictive value of 0.92 (0.89 to 0.94), positive likelihood ratio of 10.46 (6.21 to 17.63), negative likelihood ratio of 0.65 (0.55 to 0.78), and diagnostic odds ratio of 15.98 (8.38 to 30.47). Lowering the postload glucose values (75 g OGTT cut-off values of 5.1, 8.9, and 7.8 mmol/L) improved the detection rate (53%, 95% confidence interval 41% to 64%) and negative predictive value (0.94, 0.91 to 0.95), but decreased the specificity (0.91, 0.88 to 0.93) and positive predictive value (0.42, 0.32 to 0.53) at a false positive rate of 9% (positive likelihood ratio 5.59, 4.0 to 7.81; negative likelihood ratio 0.64, 0.52 to 0.77; and diagnostic odds ratio 10.07, 6.26 to 18.31).

Conclusions

The results of this prospective low risk cohort study indicated that the 75 g OGTT as a screening tool in early pregnancy is not sensitive enough when applying WHO 2013 criteria. Postload glucose values were higher in early pregnancy complicated by diabetes in pregnancy. Lowering the postload cut-off values identified a high risk group for later development of gestational diabetes mellitus or those who might benefit from earlier treatment. Results from randomised controlled trials showing a beneficial effect of early intervention are unclear.

Trial registration

ClinicalTrials.gov NCT02035059.

Timing of gestational diabetes diagnosis, gestational weight gains and offspring growth trajectory: a prospective birth cohort study

BACKGROUND

The evidence on the associations of the timing of maternal gestational diabetes mellitus (GDM) with the comprehensive growth trajectory from perinatal to early childhood in offspring is limited. The potential mechanism remains elusive. Our aim is to estimate the associations of the timing of GDM diagnosis and gestational weight gains (GWG) with the growth trajectory of children from perinatal to early childhood.

METHODS

A total of 7609 participants are included from the Maternal & Infants Health in Hefei cohort study. Primary predictors were the timing of maternal GDM diagnosis and GWG during pregnancy. The main outcomes included fetal ultrasonic measurements, birth size as well as BMI peak indicators during infancy within 48 months.

RESULTS

GDM diagnosed before 26 weeks was associated with increased risks of overgrowth for fetal abdominal circumference (OR 1.19, 95% CI 1.04-1.36) and birth weight (OR 1.51, 95% CI 1.19-1.91) when compared with unexposed. GDM diagnosis < 26 weeks was related to the higher BMI peak (β 0.16, 95%CI 0.03-0.28) within 48 months. The significantly additive impacts of maternal early GDM diagnosis and excessive gestational weight gains (EGWG) on offspring overgrowth were observed. Women in GDM < 26 weeks with early EGWG group had higher levels of hsCRP compared with GDM > 26 weeks (P < 0.001).

CONCLUSIONS

Exposure to maternal GDM diagnosed before 26 weeks with early EGWG could lead to shifts and/or disruptions from the typical growth trajectory from perinatal to early childhood in offspring.

Prevalence of gestational diabetes mellitus, maternal obesity and associated perinatal outcomes over 10 years in an Australian tertiary maternity provider

BACKGROUND

The International Association of Diabetes in Pregnancy Study Groups (IADPSG) gestational diabetes mellitus (GDM) criteria have been heavily scrutinised with concerns that the consequent GDM prevalence increase has not been associated with improved perinatal outcomes.

AIMS

At a tertiary hospital in Melbourne, Australia we aimed to evaluate prevalence trends for GDM, type 2 diabetes (T2DM), maternal obesity and large-for-gestational age (LGA) and assess changes in perinatal outcomes following IADPSG criteria uptake in 2015.

METHODS

A retrospective cohort study of singleton births from 20 weeks' gestation was conducted between 1st January 2011 and 31st December 2020. Maternal characteristics and perinatal outcomes were extracted from medical records.

RESULTS

52,795 pregnancies were included. GDM prevalence increased 2.7 times from 8.9% in 2011 to 23.7% in 2020 and increased annually by 8.59% (95%CI 7.77, 9.42). The rate of T2DM increased annually by 11.69% (95%CI 7.72, 16.67). Obesity prevalence increased annually by 3.18% (95%CI 2.58, 3.78). Induction of labour (IOL) prevalence increased annually by 8.35% (95%CI 5.69, 11.06). LGA prevalence remained unchanged. Increasing maternal obesity was the major contributing factor for LGA prevalence.

CONCLUSIONS

From 2011 to 2020 GDM, obesity and T2DM prevalence increased significantly, with associated increased IOL, without change in LGA rates. Prospective studies are required to explore interactions between GDM, obesity, LGA and obstetric interventions.

Pre-pregnancy weight, the rate of gestational weight gain, and the risk of early gestational diabetes mellitus among women registered in a tertiary care hospital in India

BACKGROUND

The impact of pre-pregnancy weight and the rate of gestational weight gain (GWG) together on the risk of early GDM (< 24 weeks gestation; eGDM) has not been studied in the Indian context. We aimed to study the influence of (1) pre-pregnancy weight on the risk of eGDM diagnosed in two time intervals; and (2) in addition, the rate of GWG by 12 weeks on the risk of eGDM diagnosed in 19-24 weeks.

METHOD

Our study utilized real-world clinical data on pregnant women routinely collected at an antenatal care clinic at a private tertiary hospital, in Pune, India. Women registering before 12 weeks of gestation (v1), with a singleton pregnancy, and having a follow-up visit between 19-24 weeks (v2) were included (n = 600). The oral glucose tolerance test was conducted universally as per Indian guidelines (DIPSI) at v1 and v2 for diagnosing eGDM. The data on the onset time of eGDM were interval censored; hence, we modeled the risk of eGDM using binomial regression to assess the influence of pre-pregnancy weight on the risk of eGDM in the two intervals. The rate of GWG by 12 weeks was added to assess its impact on the risk of eGDM diagnosed in v2.

RESULT

Overall, 89 (14.8%) women (age 32 ± 4 years) were diagnosed with eGDM by 24 weeks, of which 59 (9.8%) were diagnosed before 12 weeks and 30 of 541 (5.5%) women were diagnosed between 19-24 weeks. Two-thirds (66%) of eGDM were diagnosed before 12 weeks of gestation. Women's pre-pregnancy weight was positively associated with the risk of GDM in both time intervals though the lower confidence limit was below zero in v1. The rate of GWG by 12 weeks was not observed to be associated with the risk of eGDM diagnosed between 19-24 weeks of gestation. These associations were independent of age, height, and parity.

CONCLUSION

Health workers may focus on pre-pregnancy weight, a modifiable risk factor for eGDM. A larger community-based study measuring weight and GDM status more frequently may be warranted to deepen the understanding of the role of GWG as a risk factor for GDM.