Research Gaps in Gestational Diabetes Mellitus: Executive Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop

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.

Identification and validation of gestational diabetes subgroups by data-driven cluster analysis

AIMS/HYPOTHESIS

Gestational diabetes mellitus (GDM) is a heterogeneous condition. Given such variability among patients, the ability to recognise distinct GDM subgroups using routine clinical variables may guide more personalised treatments. Our main aim was to identify distinct GDM subtypes through cluster analysis using routine clinical variables, and analyse treatment needs and pregnancy outcomes across these subgroups.

METHODS

In this cohort study, we analysed datasets from a total of 2682 women with GDM treated at two central European hospitals (1865 participants from Charité University Hospital in Berlin and 817 participants from the Medical University of Vienna), collected between 2015 and 2022. We evaluated various clustering models, including k-means, k-medoids and agglomerative hierarchical clustering. Internal validation techniques were used to guide best model selection, while external validation on independent test sets was used to assess model generalisability. Clinical outcomes such as specific treatment needs and maternal and fetal complications were analysed across the identified clusters.

RESULTS

Our optimal model identified three clusters from routinely available variables, i.e. maternal age, pre-pregnancy BMI (BMIPG) and glucose levels at fasting and 60 and 120 min after the diagnostic OGTT (OGTT0, OGTT60 and OGTT120, respectively). Cluster 1 was characterised by the highest OGTT values and obesity prevalence. Cluster 2 displayed intermediate BMIPG and elevated OGTT0, while cluster 3 consisted mainly of participants with normal BMIPG and high values for OGTT60 and OGTT120. Treatment modalities and clinical outcomes varied among clusters. In particular, cluster 1 participants showed a much higher need for glucose-lowering medications (39.6% of participants, compared with 12.9% and 10.0% in clusters 2 and 3, respectively, p<0.0001). Cluster 1 participants were also at higher risk of delivering large-for-gestational-age infants. Differences in the type of insulin-based treatment between cluster 2 and cluster 3 were observed in the external validation cohort.

CONCLUSIONS/INTERPRETATION

Our findings confirm the heterogeneity of GDM. The identification of subgroups (clusters) has the potential to help clinicians define more tailored treatment approaches for improved maternal and neonatal outcomes.

Predictors and Trends in First-Trimester Hemoglobin A1c Screening in New York City, 2009 to 2017

Glycated hemoglobin is an adjunct tool in early pregnancy to assess glycemic control. We examined trends and maternal predictors for those who had A1c screening in early pregnancy using hospital discharge and vital registry data between 2009 and 2017 linked with the New York City A1C Registry (N = 798,312). First-trimester A1c screening increased from 2.3% in 2009 to 7.7% in 2017. The likelihood of screening became less targeted to high-risk patients over time, with a decrease in mean A1c values from 5.8% (95% confidence interval [CI]: 5.8, 5.9) to 5.3 (95% CI: 5.3, 5.4). The prevalence of gestational diabetes mellitus increased while testing became less discriminate for those with high-risk factors, including pregestational type 2 diabetes, chronic hypertension, obesity, age over 40 years, as well as Asian or Black non-Hispanic race/ethnicity. KEY POINTS: · First-trimester A1c screening increased from 2.3% in 2009 to 7.7% in 2017 in New York City.. · The likelihood of screening became less targeted to high-risk patients over time.. · The prevalence of gestational diabetes mellitus increased, while testing became less discriminate..

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.

Gestational diabetes: One size does not fit all-an observational study of maternal and neonatal outcomes by maternal glucose profile

OBJECTIVES

To examine obstetrical and neonatal outcomes across maternal glucose profiles at the population level and to explore insulin sensitivity and beta-cell function across profiles in an independent, well-phenotyped cohort for potential pathophysiologic explanation.

RESEARCH DESIGN AND METHODS

Observational cohort study of all pregnancies with gestational diabetes screening between October 2008 and December 2018 resulting in live singleton birth in Alberta, Canada (n = 436,773) were categorized into seven maternal glucose profiles: (1) normal 50 g-glucose challenge test (nGCT), (2) normal 75-g OGTT (nOGTT), (3) isolated elevated 1 h post-load glucose (ePLPG1), (4) isolated elevated 2 h post-load glucose (ePLPG2), (5) elevated 1 and 2 h post-load glucose (ePLPG12), (6) isolated elevated FPG (eFPG), and (7) elevated FPG + elevated 1-h and/or 2-h PLG (Combined). Primary outcomes were large for gestational age (LGA) and neonatal intensive care unit (NICU) admission rates. An independent observational cohort of 1451 women was examined for measures of beta-cell function (ISSI-2, insulinogenic index/HOMA-IR) and insulin sensitivity/resistance (Matsuda index, HOMA-IR) by similar maternal glucose profiles.

RESULTS

Pregnancies with elevated FPG, either isolated or combined, had higher adverse events and lower insulin sensitivity. The combination of elevated FPG + elevated 1-h and/or 2-h PLG had the highest rates of LGA(20.9%), NICU admissions (14.7%), and lowest insulin sensitivity as measured by Matsuda index and HOMA-IR, and beta-cell function as measured by ISSI-2 and Insulinogenic index/HOMA-IR.

CONCLUSIONS

Elevated fasting plasma glucose, either alone or combined with post-load glucose elevation is associated with worse outcomes than isolated post-load glucose elevation, possibly due to higher degrees of insulin resistance. Future work is needed to better understand these differences, and explore whether tailored treatment of GDM can improve neonatal outcomes.

Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

BACKGROUND

Numerous laboratory tests are used in the diagnosis and management of diabetes mellitus. The quality of the scientific evidence supporting the use of these assays varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for laboratory analysis in screening, diagnosis, or monitoring of diabetes. The overall quality of the evidence and the strength of the recommendations were evaluated. The draft consensus recommendations were evaluated by invited reviewers and presented for public comment. Suggestions were incorporated as deemed appropriate by the authors (see Acknowledgments). The guidelines were reviewed by the Evidence Based Laboratory Medicine Committee and the Board of Directors of the American Association for Clinical Chemistry and by the Professional Practice Committee of the American Diabetes Association.

CONTENT

Diabetes can be diagnosed by demonstrating increased concentrations of glucose in venous plasma or increased hemoglobin A1c (HbA1c) in the blood. Glycemic control is monitored by the people with diabetes measuring their own blood glucose with meters and/or with continuous interstitial glucose monitoring (CGM) devices and also by laboratory analysis of HbA1c. The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of ketones, autoantibodies, urine albumin, insulin, proinsulin, and C-peptide are addressed.

SUMMARY

The guidelines provide specific recommendations based on published data or derived from expert consensus. Several analytes are found to have minimal clinical value at the present time, and measurement of them is not recommended.

Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

BACKGROUND

Numerous laboratory tests are used in the diagnosis and management of diabetes mellitus. The quality of the scientific evidence supporting the use of these assays varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for laboratory analysis in screening, diagnosis, or monitoring of diabetes. The overall quality of the evidence and the strength of the recommendations were evaluated. The draft consensus recommendations were evaluated by invited reviewers and presented for public comment. Suggestions were incorporated as deemed appropriate by the authors (see Acknowledgments). The guidelines were reviewed by the Evidence Based Laboratory Medicine Committee and the Board of Directors of the American Association of Clinical Chemistry and by the Professional Practice Committee of the American Diabetes Association.

CONTENT

Diabetes can be diagnosed by demonstrating increased concentrations of glucose in venous plasma or increased hemoglobin A1c (Hb A1c) in the blood. Glycemic control is monitored by the people with diabetes measuring their own blood glucose with meters and/or with continuous interstitial glucose monitoring (CGM) devices and also by laboratory analysis of Hb A1c. The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of ketones, autoantibodies, urine albumin, insulin, proinsulin, and C-peptide are addressed.

SUMMARY

The guidelines provide specific recommendations based on published data or derived from expert consensus. Several analytes are found to have minimal clinical value at the present time, and measurement of them is not recommended.

Evaluating glucose variability through OGTT in early pregnancy and its association with hypertensive disorders of pregnancy in non-diabetic pregnancies: a large-scale multi-center retrospective study

BACKGROUND

Recent evidence suggests increased glucose variability (GV) causes endothelial dysfunction, a central pathology of hypertensive disorders of pregnancy (HDP). We aimed to investigate the association between GV in early pregnancy and subsequent HDP development among non-diabetes mellitus (DM) pregnancies.

METHODS

This multicenter retrospective study used data from singleton pregnancies between 2009 and 2019. Among individuals who had 75 g-OGTT before 20 weeks of gestation, we evaluated GV by 75 g-OGTT parameters and examined its relationship with HDP development, defining an initial-increase from fasting-plasma glucose (PG) to 1-h-PG and subsequent-decrease from 1-h-PG to 2-h-PG.

RESULTS

Approximately 3.0% pregnancies (802/26,995) had 75 g-OGTT before 20 weeks of gestation, and they had a higher prevalence of HDP (14.3% vs. 7.5%). The initial-increase was significantly associated with overall HDP (aOR 1.20, 95% CI 1.02-1.42), and the subsequent-decrease was associated with decreased and increased development of early-onset (EoHDP: aOR 0.56, 95% CI 0.38-0.82) and late-onset HDP (LoHDP: aOR 1.38, 95% CI 1.11-1.73), respectively.

CONCLUSIONS

A pattern of marked initial-increase and minor subsequent-decrease (i.e., sustained hyperglycemia) was associated with EoHDP. Contrarily, the pattern of marked initial-increase and subsequent-decrease (i.e., increased GV) was associated with LoHDP. This provides a new perspective for future study strategies.

Evaluating the effect of gestational diabetes mellitus on macrosomia based on the characteristics of oral glucose tolerance test

BACKGROUND

GDM is always treated as a homogenous disease ignoring the different metabolic characteristics in oral glucose tolerance test (OGTT). We assessed the effect of GDM on macrosomia based on the different characteristics of OGTT.

METHODS

We retrospectively divided 998 GDM pregnant women into 7 groups, Group A1: abnormal OGTT_0h; Group A2: abnormal OGTT_{1 h}; Group A3: abnormal OGTT_{2 h}; Group B1: abnormal OGTT_{0h+1 h}; Group B2: abnormal OGTT_{0h+2 h}; Group B3: abnormal OGTT_{1 h+2 h}; Group C: abnormal OGTT_{0h+1 h+2 h}; RESULTS: The incidence of macrosomia in group C (21.92%) was higher than other groups. The OR of OGTT_{0h+1 h+2 h} was significant (OGTT_{1 h}: OR=1.577, 95% CI: 0.791, 3.145; OGTT_{2 h}: OR=1.151, 95% CI: 0.572, 2.313; OGTT_{0h+1 h}: OR=1.346, 95% CI: 0.584, 3.101; OGTT_{0h+2 h}: OR=1.327, 95% CI: 0.517, 3.409; OGTT_{1 h+2 h}: OR=0.771, 95% CI: 0.256, 2.322; OGTT_{0h+1 h+2 h}: OR=4.164, 95% CI: 2.095, 8.278) when comparing with OGTT_0h. Subgroup analysis showed abnormal OGTT_{0h+1 h+2 h} might contribute more to macrosomia in pre-pregnancy BMI ≥ 24 kg/m² than those with BMI < 24 kg/m².

CONCLUSION

The effect of abnormal OGTT_{0h+1 h+2 h} on macrosomia was significantly greater than other OGTT characteristics, especially for those with pre-pregnancy BMI ≥ 24 kg/m². Individualized management of GDM based on OGTT characteristics and pre-pregnancy BMI might be needed.

Large maternal waist circumference in relation to height is associated with high glucose concentrations in an early-pregnancy oral glucose tolerance test: A population-based study

INTRODUCTION

To explore the role of maternal anthropometric characteristics in early-pregnancy glycemia, we analyzed the associations and interactions of maternal early-pregnancy waist circumference (WC), height and pre-pregnancy body mass index (BMI) with plasma glucose concentrations in an oral glucose tolerance test (OGTT) at 12-16 weeks' gestation.

MATERIAL AND METHODS

A population-based cohort of 1361 pregnant women was recruited in South Karelia, Finland, from March 2013 to December 2016. All participants had their WC, weight, height, HbA_1c , and blood pressure measured at 8-14 weeks' gestation and subsequently underwent a 2-h 75-g OGTT, including assessment of fasting insulin concentrations, at 12-16 weeks' gestation. BMI (kg/m² ) was calculated using self-reported pre-pregnancy weight. Maternal WC ≥80 cm was defined as large. Maternal height ≥166 cm was defined as tall. Data on gestational diabetes treatment was extracted from hospital records.

RESULTS

In the total cohort, 901 (66%) of women had an early-pregnancy WC ≥80 cm, which was associated with higher early-pregnancy HbA_1c, higher concentrations of  fasting plasma glucose and serum insulin, higher post-load plasma glucose concentrations, higher HOMA-IR indices, higher blood pressure levels, and higher frequencies of pharmacologically treated gestational diabetes, than early-pregnancy WC <80 cm. Maternal height ≥166 cm was negatively associated with 1- and 2-h post-load plasma glucose concentrations. Waist-to-height ratio (WHtR) >0.5 was positively associated with both fasting and post-load plasma glucose concentrations at 12-16 weeks' gestation, even when adjusted for age, smoking, nulliparity, and family history of type 2 diabetes. The best cut-offs for WHtR (0.58 for 1-h plasma glucose, and 0.54 for 2-h plasma glucose) were better predictors of post-load glucose concentrations >90th percentile than the best cut-offs for BMI (28.1 kg/m² for 1-h plasma glucose, and 26.6 kg/m² for 2-h plasma glucose), with areas-under-the-curve (95% confidence interval) 0.73 (0.68-0.79) and 0.73 (0.69-0.77), respectively, for WHtR, and 0.68 (0.63-0.74) and 0.69 (0.65-0.74), respectively, for BMI.

CONCLUSIONS

In our population-based cohort, early-pregnancy WHtR >0.5 was positively associated with both fasting and post-load glucose concentrations at 12-16 weeks' gestation and performed better than BMI in the prediction of post-load glucose concentrations >90th percentile. Overall, our results underline the importance of evaluating maternal abdominal adiposity in gestational diabetes risk assessment.

Mouse Models of Gestational Diabetes Mellitus and Its Subtypes: Recent Insights and Pitfalls

Gestational diabetes mellitus (GDM) is currently the most common complication of pregnancy and is defined as a glucose intolerance disorder with recognition during pregnancy. GDM is considered a uniform group of patients in conventional guidelines. In recent years, evidence of the disease's heterogeneity has led to a growing understanding of the value of dividing patients into different subpopulations. Furthermore, in view of the increasing incidence of hyperglycemia outside pregnancy, it is likely that many cases diagnosed as GDM are in fact patients with undiagnosed pre-pregnancy impaired glucose tolerance (IGT). Experimental models contribute significantly to the understanding of the pathogenesis of GDM and numerous animal models have been described in the literature. The aim of this review is to provide an overview of the existing mouse models of GDM, in particular those that have been obtained by genetic manipulation. However, these commonly used models have certain limitations in the study of the pathogenesis of GDM and cannot fully describe the heterogeneous spectrum of this polygenic disease. The polygenic New Zealand obese (NZO) mouse is introduced as a recently emerged model of a subpopulation of GDM. Although this strain lacks conventional GDM, it exhibits prediabetes and an IGT both preconceptionally and during gestation. In addition, it should be emphasized that the choice of an appropriate control strain is of great importance in metabolic studies. The commonly used control strain C57BL/6N, which exhibits IGT during gestation, is discussed in this review as a potential model of GDM.

Treatment of Gestational Diabetes Mellitus and Maternal Risk of Diabetes After Pregnancy

OBJECTIVE

To compare postpartum glucose tolerance between women treated for gestational diabetes mellitus (GDM) and those not treated.

RESEARCH DESIGN AND METHODS

Metabolic testing was performed at 3 and 12 months postpartum in 599 women comprising the following gestational glucose tolerance groups: 1) normal glucose challenge test (GCT) and oral glucose tolerance test (OGTT) during pregnancy, 2) abnormal GCT with normal OGTT, 3) gestational impaired glucose tolerance, 4) mild untreated GDM, and 5) severe treated GDM.

RESULTS

Birth weight progressively increased across groups 1-4 before falling steeply in treated GDM (P < 0.0001). In contrast, at 3 and 12 months, insulin sensitivity and β-cell function progressively decreased across the five groups, mirrored by rising fasting and 2-h glucose (all P < 0.0001). Accordingly, prevalence of prediabetes/diabetes at 12 months increased in a stepwise manner across groups 1-5 (2.8%, 9.6%, 13.5%, 21.5%, and 32.6%, respectively; P < 0.0001).

CONCLUSIONS

Treating GDM lowers birth weight but does not disrupt the association between gestational glycemia and maternal prediabetes/diabetes after pregnancy.

Prepregnancy body mass index and gestational diabetes mellitus across Asian and Pacific Islander subgroups in California

BACKGROUND

The American College of Obstetricians and Gynecologists recommends early screening for gestational diabetes mellitus among pregnant Asian people with a prepregnancy body mass index ≥23.0 kg/m2, in contrast with the recommended screening at a body mass index ≥25 kg/m2 for other races and ethnicities. However, there is significant heterogeneity within Asian and Pacific Islander populations, and gestational diabetes mellitus and its association with body mass index among Asian and Pacific Islander subgroups may not be uniform across all groups.

OBJECTIVE

This study aimed to analyze the association between body mass index and gestational diabetes mellitus among Asian and Pacific Islander subgroups in California, specifically gestational diabetes mellitus rates among those with a body mass index above vs below 23 kg/m2, which is the cutoff point for the designation of being overweight among Asians populations.

STUDY DESIGN

Using a linked delivery hospitalization discharge and vital records database, we identified patients who gave birth in California between 2007 and 2017 and who self-reported to be 1 of 13 Asian and Pacific Islander subgroups, which was collected from birth and fetal death certificates. In each subgroup, we evaluated the association between body mass index and gestational diabetes mellitus using multivariable logistic regression models adjusted for age, education, parity, payment method, the trimester in which prenatal care was initiated, and nativity. We fit body mass index nonlinearly with splines and categorized body mass index as being above or below 23 kg/m2. Predicted probabilities of gestational diabetes mellitus with 95% confidence intervals were calculated across body mass index values using the nonlinear regression models.

RESULTS

The overall prevalence of gestational diabetes mellitus was 14.3% (83,400/584,032), ranging between 8.4% and 17.1% across subgroups. The highest prevalence was among Indian (17.1%), Filipino (16.7%), and Vietnamese (15.5%) subgroups. In these subgroups, gestational diabetes mellitus was diagnosed in 10% to 13% of those with a body mass index <23.0 kg/m2 and in 22% of those with a body mass index ≥23 kg/m2. Gestational diabetes mellitus was least common among Korean (8.4%), Japanese (9.0%), and Samoan (9.8%) subgroups with a gestational diabetes mellitus rate of 5% to 7% among those with a body mass index <23.0 kg/m2 and in 10% to 15% among those with a body mass index ≥23 kg/m2. Although Samoan patients had the highest rate of obesity, defined as body mass index ≥30 kg/m2 (57.4%), they had the third lowest prevalence of gestational diabetes mellitus. Conversely, Vietnamese patients had the second lowest rate of obesity (2.4%) but the highest rate of gestational diabetes mellitus at a body mass index of ≥23 kg/m2 (22.3%).

CONCLUSION

Gestational diabetes mellitus and its association with body mass index varied among Asian subgroups but increased as body mass index increased. Subgroups with the lowest prevalence of obesity trended toward a higher prevalence of gestational diabetes mellitus and those with a higher prevalence of obesity trended toward a lower prevalence of gestational diabetes mellitus.

New Developments, Challenges and Open Questions in Diagnosis and Treatment of Gestational Diabetes Mellitus

The prevalence of gestational diabetes mellitus (GDM) is increasing alongside a rising maternal age at conception, an increasing number of people making unhealthy lifestyle choices and, especially, an increasing pregestational body weight [...].

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.

Impact of earlier gestational diabetes screening for pregnant people with obesity on maternal and perinatal outcomes

OBJECTIVES

Gestational diabetes (GDM) screening at 24-28 weeks' gestation reduces risk of adverse maternal and perinatal outcomes. While experts recommend first-trimester screening for high-risk patients, including those with obesity, data supporting this recommendation is limited.

METHODS

We implemented a systematic population intervention to encourage first-trimester GDM screening by oral glucose tolerance testing in a cohort of pregnant people with obesity in two integrated health systems from 2009 to 2013, and compared outcomes to the same population pre-intervention (2006-2009). Up to five years of postpartum glucose testing results (through 2018) were assessed among GDM cases in the post-intervention group. Primary outcomes were large-for-gestational-age birthweight (LGA); macrosomia; a perinatal composite outcome; gestational hypertension/preeclampsia; cesarean delivery; and medication treatment of GDM.

RESULTS

A total of 40,206 patients (9,156 with obesity) were screened for GDM; 2,672 (6.6%) were diagnosed with GDM. Overall, multivariate adjusted risk for LGA and cesarean delivery were lower following the intervention (LGA: aOR 0.89 [0.82, 0.96]; cesarean delivery: 0.89 [0.85, 0.93]). This difference was more pronounced in patients diagnosed with GDM (LGA: aOR 0.52 [0.39, 0.70]; cesarean delivery 0.78 [0.65, 0.94]); insulin/oral hypoglycemic treatment rates for GDM were also higher post-intervention than pre-intervention (22 vs. 29%; p<0.0001). There were no differences for the other primary outcomes. Only 20% of patients diagnosed with GDM early in pregnancy who had postpartum testing had results in the overt diabetes range, suggesting a spectrum of diabetes detected early in pregnancy.

CONCLUSIONS

First trimester GDM screening for pregnant people with obesity may improve GDM-associated outcomes.

Early pregnancy glycaemia predicts postpartum diabetes mellitus

OBJECTIVE

To determine the association between early pregnancy glycaemia, as measured by glycosylated haemoglobin A1c (HbA1c) at the first prenatal visit, and persistent postpartum diabetes mellitus (DM).

STUDY DESIGN

All women first diagnosed with DM during pregnancy who had both HbA1c prior to 24 weeks and postpartum DM testing were included. The proportions of women with normal (<5.7%), prediabetic (5.7-6.4%) and elevated (≥6.5%) early HbA1c who tested positive for postpartum DM were compared. Test characteristics of HbA1c to predict persistent postpartum DM were calculated.

RESULTS

One hundred and twenty-one women met the study inclusion criteria. HbA1c was obtained at a median gestational age of 9 weeks. Twenty-two women (18.2%) had persistent postpartum DM, which was highly correlated with early HbA1c: 16 (73%) women had an elevated HbA1c, five (22.7%) women had a prediabetic HbA1c and only one (4.5%) woman had a normal HbA1c. Of 65 women with gestational DM and a normal early HbA1c, only one (1.5%) had persistent DM within the first year (negative predictive value 98.5%). Sixteen of 18 women with an elevated early HbA1c had persistent postpartum DM (positive predictive value 88.9%). These percentages were significant overall and between groups (p < 0.001). No clinical or demographic factors were highly predictive of postpartum DM.

CONCLUSIONS

Early pregnancy glycaemia, as measured by HbA1c at the first prenatal visit, is highly predictive of persistent postpartum DM, and may allow clinically important risk stratification to prioritize postpartum testing and care. Postpartum DM is rare amongst women with gestational DM who begin the pregnancy with a normal HbA1c, while postpartum DM is highly likely for those with an elevated HbA1c in early pregnancy. Nearly three-quarters of women who tested positive for DM post partum had an elevated HbA1c in early pregnancy, indicating that they had undiagnosed DM prior to conception.

The utility of first trimester plasma glycated CD59 (pGCD59) in predicting gestational diabetes mellitus: A prospective study of non-diabetic pregnant women in Ireland

AIMS

To evaluate the ability of first trimester plasma glycated CD59 (pGCD59) to predict gestational diabetes mellitus (GDM) at 24-28 weeks of gestation.

METHODS

Prospectively, in 378 pregnant women, GDM was diagnosed using the one step 2 h 75 g oral glucose tolerance test adjudicated by the World Health Organisation (WHO) 2013 criteria. The ability of pGCD59 to predict GDM was assessed using receiver operating characteristic (ROC) curves adjusted for maternal age, body mass index (BMI), maternal ethnicity, parity, previous GDM, family history of diabetes mellitus and week of gestation at time of pGCD59 sampling.

RESULTS

pGCD59 generated an adjusted area under the curve (AUC) of (a) 0.63 (95 %CI:0.56-0.70, p < 0.001) for predicting GDM, and (b) 0.71 (95 %CI:0.62-0.79, p < 0.001 for GDM diagnosed with a fasting plasma glucose (FPG) ≥ 5.1 mmol/L. Sensitivity analysis of BMI subgroups showed that pGCD59 generated the highest AUC in the 35 kg/m² ≤ BMI < 40 kg/m² (AUC:0.85, 95 %CI:0.70-0.98) and BMI ≥ 40 kg/m² (AUC:0.88, 95 %CI:0.63-0.99) categories.

CONCLUSIONS

Early in pregnancy, pGCD59 may be a good predictor of GDM in women with a high BMI and a fair predictor of GDM diagnosed by an elevated FPG independent of BMI.

Risk of Adverse Pregnancy Outcomes Among Pregnant Individuals With Gestational Diabetes by Race and Ethnicity in the United States, 2014-2020

IMPORTANCE

Gestational diabetes, which increases the risk of adverse pregnancy outcomes, has been increasing in frequency across all racial and ethnic subgroups in the US.

OBJECTIVE

To assess whether the frequency of adverse pregnancy outcomes among those in the US with gestational diabetes changed over time and whether the risk of these outcomes differed by maternal race and ethnicity.

DESIGN, SETTING, AND PARTICIPANTS

Exploratory serial, cross-sectional, descriptive study using US National Center for Health Statistics natality data for 1 560 822 individuals with gestational diabetes aged 15 to 44 years with singleton nonanomalous live births from 2014 to 2020 in the US.

EXPOSURES

Year of delivery and race and ethnicity, as reported on the birth certificate, stratified as non-Hispanic American Indian, non-Hispanic Asian/Pacific Islander, non-Hispanic Black, Hispanic/Latina, and non-Hispanic White (reference group).

MAIN OUTCOMES AND MEASURES

Maternal outcomes of interest included cesarean delivery, primary cesarean delivery, preeclampsia or gestational hypertension, intensive care unit (ICU) admission, and transfusion; neonatal outcomes included large for gestational age (LGA), macrosomia (>4000 g at birth), small for gestational age (SGA), preterm birth, and neonatal ICU (NICU) admission, as measured by the frequency (per 1000 live births) with estimation of mean annual percentage change (APC), disparity ratios, and adjusted risk ratios.

RESULTS

Of 1 560 822 included pregnant individuals with gestational diabetes (mean [SD] age, 31 [5.5] years), 1% were American Indian, 13% were Asian/Pacific Islander, 12% were Black, 27% were Hispanic/Latina, and 48% were White. From 2014 to 2020, there was a statistically significant increase in the overall frequency (mean APC per year) of preeclampsia or gestational hypertension (4.2% [95% CI, 3.3% to 5.2%]), transfusion (8.0% [95% CI, 3.8% to 12.4%]), preterm birth at less than 37 weeks (0.9% [95% CI, 0.3% to 1.5%]), and NICU admission (1.0% [95% CI, 0.3% to 1.7%]). There was a significant decrease in cesarean delivery (-1.4% [95% CI, -1.7% to -1.1%]), primary cesarean delivery (-1.2% [95% CI, -1.5% to -0.9%]), LGA (-2.3% [95% CI, -2.8% to -1.8%]), and macrosomia (-4.7% [95% CI, -5.3% to -4.0%]). There was no significant change in maternal ICU admission and SGA. In comparison with White individuals, Black individuals were at significantly increased risk of all assessed outcomes, except LGA and macrosomia; American Indian individuals were at significantly increased risk of all assessed outcomes except cesarean delivery and SGA; and Hispanic/Latina and Asian/Pacific Islander individuals were at significantly increased risk of maternal ICU admission, preterm birth, NICU admission, and SGA. Differences in adverse outcomes by race and ethnicity persisted through these years.

CONCLUSIONS AND RELEVANCE

From 2014 through 2020, the frequency of multiple adverse pregnancy outcomes in the US increased among pregnant individuals with gestational diabetes. Differences in adverse outcomes by race and ethnicity persisted.

Longitudinal changes in glucose during pregnancy in women with gestational diabetes risk factors

AIMS/HYPOTHESIS

Despite recommendations to screen women with diabetes risk factors for hyperglycaemia in the first trimester, criteria for normal glucose values in early pregnancy have not been firmly established. We aimed to compare glucose levels in early pregnancy with those later in gestation and outside of pregnancy in women with diabetes risk factors.

METHODS

In pregnant women (N = 123) followed longitudinally through the postpartum period, and a separate cohort of non-pregnant women (N = 65), we performed 75 g oral glucose tolerance tests. All participants had one or more risk factors for diabetes. Using linear regression, we tested for differences in glucose levels between non-pregnant and pregnant women at early (7-15 weeks) and mid-late (24-32 weeks) gestation as well as postpartum, with adjustment for maternal age, parity, marital status and BMI. In a longitudinal analysis using mixed-effects models, we tested for differences in glucose levels across early and mid-late pregnancy compared with postpartum. Differences are expressed as β (95% CI).

RESULTS

Fasting glucose was lower in pregnant compared with non-pregnant women by 0.34 (0.18, 0.51) mmol/l (p < 0.0001) in early pregnancy and by 0.45 (0.29, 0.61) mmol/l (p < 0.0001) in mid-late pregnancy. In longitudinal models, fasting glucose was lower by 0.13 (0.04, 0.21) mmol/l (p = 0.003) in early pregnancy and by 0.16 (0.08, 0.25) mmol/l (p = 0.0003) in mid-late pregnancy compared with the same women postpartum. Early pregnancy post-load glucose levels did not differ from those in non-pregnant women or the same women postpartum. In mid-late pregnancy, compared with non-pregnant women, elevations in 1 h post-load glucose level (0.60 [-0.12, 1.33] mmol/l, p = 0.10) and 2 h post-load glucose (0.49 [-0.21, 1.19] mmol/l, p = 0.17) were not statistically significant. However, in longitudinal analyses, 1 h and 2 h post-load glucose levels were higher in mid-late pregnancy (by 0.78 [0.35, 1.21] mmol/l, p = 0.0004, and 0.67 [0.30, 1.04] mmol/l, p = 0.0005, respectively) when compared with postpartum.

CONCLUSIONS/INTERPRETATION

In women with diabetes risk factors, fasting glucose declines in the first trimester. Post-load glucose increases later in pregnancy. These findings may inform criteria for diagnosing hyperglycaemia early in pregnancy.

Impact Of Prepregnancy Overweight And Obesity On Treatment Modality And Pregnancy Outcome In Women With Gestational Diabetes Mellitus

BACKGROUND

We aim to evaluate the impact of prepregnancy overweight on treatment modalities of Gestational Diabetes Mellitus (GDM). We assessed the association of increased pregravid Body Mass Index (BMI) with dosing of basal and rapid acting insulin as well as pregnancy outcome.

METHODS

We included 509 gestational diabetic women (normal weight: 200, overweight: 157, obese: 152), attending the pregnancy outpatient clinic at the Department of Obstetrics and Gynecology, Medical University of Vienna, in this retrospective study. We used a prospectively compiled database to assess patient characteristics, treatment approaches - particularly maximum doses of basal and rapid acting insulin or metformin - and pregnancy outcome.

RESULTS

Increased BMI was associated with the need of glucose lowering medication (odds ratio (OR): 1.08 for the increase of 1 kg/m² BMI, 95%CI 1.05-1.11, p<0.001). Mothers with pregestational obesity received the highest amount of insulin. Metformin was more often used in patients with obesity who also required higher daily doses. Maternal BMI was associated with increased risk of cesarean section (OR 1.04, 95%CI 1.01-1.07, p<0.001) and delivering large for gestational age offspring (OR 1.09, 95%CI 1.04-1.13, p<0.001). Birthweight percentiles were highest in patients with obesity who required glucose lowering therapy.

CONCLUSIONS

Treatment modalities and outcome in GDM pregnancies are closely related to the extent of maternal BMI. Patients with obesity required glucose lowering medication more often and were at higher risk of adverse pregnancy outcomes. It is crucial to further explore the underlying pathophysiologic mechanisms to optimize clinical management and individual treatment approaches.

Characterizing and Evaluating Diurnal Salivary Uric Acid Across Pregnancy Among Healthy Women

Uric acid levels during pregnancy have been examined as a potential indicator of risk for gestational diabetes mellites, hypertension, and related adverse birth outcomes. However, evidence supporting the utility of serum uric acid levels in predicting poor maternal and fetal health has been mixed. The lack of consistent findings may be due to limitations inherent in serum-based biomeasure evaluations, such as minimal repeated assessments and variability in the timing of these assessments. To address these gaps, we examined repeated measurements of diurnal salivary uric acid (sUA) levels in a sample of 44 healthy women across early-mid and late pregnancy. We assessed potential covariates and confounds of sUA levels and diurnal trajectories, as well as associations between maternal weight gain and blood pressure during pregnancy and sUA concentrations. Using multilevel linear models, we found sUA increased across pregnancy and displayed a robust diurnal pattern with the highest concentrations at waking, a steep decline in the early morning, and decreasing levels across the day. Maternal pre-pregnancy BMI, age, prior-night sleep duration, and fetal sex were associated with sUA levels and/or diurnal slopes. Maternal blood pressure and gestational weight gain also showed significant associations with sUA levels across pregnancy. Our results expand upon those found with serum UA measurements. Further, they demonstrate the feasibility of using at-home, minimally-invasive saliva sampling procedures to track UA levels across pregnancy with potential applications for the long-term monitoring of maternal cardiometabolic risk.

The Use of Oral Hypoglycemic Agents during Pregnancy: An Alternative to Insulin?

OBJECTIVE

Gestational Diabetes Mellitus (GDM) and Type 2 Diabetes Mellitus (DM2) are metabolic disorders characterized by increased insulin resistance. Although insulin is the treatment of choice in pregnant patients with DM, the prescription of oral hypoglycemic agents (OHA) has been increasing among practitioners. This study aimed to evaluate the maternal and neonatal outcomes when oral hypoglycemic agents were used in diabetic pregnant women.

METHODS

Medical records from the Maternal-Infant Care Unit Clinics SoM-UPR (n=149) were reviewed. Patients that were treated with metformin, sulfonylurea or insulin were included. Maternal and neonatal outcomes were compared between groups.

RESULTS

Patient's mean age was 28 ± 6 years. The majority had GDM (91%). The most common comorbidity was hypertension (9.9%). Lifestyle modification was used as treatment in 77% of patients during the second trimester, but its use decreased to 33% during the third trimester. Insulin was the treatment of choice. Among the OHA, sulfonylurea was preferred. Postprandial glucose levels were lower in patients who used insulin as compared to those without medications.

CONCLUSION

No significant differences were found in maternal outcomes such as C-section, induction of labor, episiotomy or preterm labor, or neonatal outcomes such as macrosomia, neonatal hypoglycemia or congenital abnormalities among treatment groups. OHA can be considered as an alternative to insulin for the treatment of DM during pregnancy in selected cases.

Characteristics of gestational diabetes subtypes classified by oral glucose tolerance test values

BACKGROUND

In clinical practice, gestational diabetes mellitus (GDM) is treated as a homogenous disease but emerging evidence suggests that the diagnosis of GDM possibly comprises different metabolic entities. In this study, we aimed to assess early pregnancy characteristics of gestational diabetes mellitus entities classified according to the presence of fasting and/or post-load hyperglycaemia in the diagnostic oral glucose tolerance test performed at mid-gestation.

METHODS

In this prospective cohort study, 1087 pregnant women received a broad risk evaluation and laboratory examination at early gestation and were later classified as normal glucose tolerant (NGT), as having isolated fasting hyperglycaemia (GDM-IFH), isolated post-load hyperglycaemia (GDM-IPH) or combined hyperglycaemia (GDM-CH) according to oral glucose tolerance test results. Participants were followed up until delivery to assess data on pharmacotherapy and pregnancy outcomes.

RESULTS

Women affected by elevated fasting and post-load glucose concentrations (GDM-CH) showed adverse metabolic profiles already at beginning of pregnancy including a higher degree of insulin resistance as compared to women with normal glucose tolerance and those with isolated defects (especially GDM-IPH). The GDM-IPH subgroup had lower body mass index at early gestation and required glucose-lowering medications less often (28.9%) as compared to GDM-IFH (47.8%, P = .019) and GDM-CH (54.5%, P = .005). No differences were observed in pregnancy outcome data.

CONCLUSIONS

Women with fasting hyperglycaemia, especially those with combined hyperglycaemia, showed an unfavourable metabolic phenotype already at early gestation. Therefore, categorization based on abnormal oral glucose tolerance test values provides a practicable basis for clinical risk stratification.

Indian Research in Gestational Diabetes Mellitus during the Past Three Decades: A Scientometric Analysis

Background

India plays an important role in global research on gestational diabetes mellitus (GDM), but a bibliometric assessment of this research is lacking.

Objective

To provide a comprehensive analysis of Indian GDM research during the last 30 years using select bibliometric indicators.

Methods

The Scopus international database was used to retrieve publication data, using a defined search strategy. The analysis focused on research output of Indian authors and organizations and their collaborations. The qualitative performance was assessed in terms of relative citation index and citations per paper (CPP).

Results

Overall, 100 countries participated in GDM research producing 13,193 publications during 1990-2019. India ranked ninth in global output (1182 publications, 3.1% share) and CPP of 18.6. Only 21.3% of publications had international collaboration and 9.4% were funded. Of the 235 organizations and 544 authors that participated in India's research on GDM, the top 50 organizations and authors contributed 53.8 and 36.4% to national publication share, respectively. The leading productive organizations were AIIMS, New Delhi, KEMH, Pune and PGIMER, Chandigarh, whereas the most productive authors were S. Kalra, V. Seshiah and C.S. Yajnik. Indian Journal of Endocrinology and Metabolism, Journal of Clinical and Diagnostic Research, Journal of Obstetrics and Gynecology of India and Diabetes Research and Clinical Practice were the most productive journals.

Conclusions

Indian research on GDM is lagging behind other countries which have a similar disease burden. Increasing national and international collaborations, and active support of national and international funding agencies is urgently required to produce quality research on GDM.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13224-021-01444-7.

TIMER: A Clinical Study of Energy Restriction in Women with Gestational Diabetes Mellitus

Medical nutrition therapy is an integral part of gestational diabetes mellitus (GDM) management; however, the prescription of optimal energy intake is often a difficult task due to the limited available evidence. The present pilot, feasibility, parallel, open-label and non-randomized study aimed to evaluate the effect of a very low energy diet (VLED, 1600 kcal/day), or a low energy diet (LED, 1800 kcal/day), with or without personalized exercise sessions, among women with GDM in singleton pregnancies. A total of 43 women were allocated to one of four interventions at GDM diagnosis: (1) VLED (n = 15), (2) VLED + exercise (n = 4), (3) LED (n = 16) or (4) LED + exercise (n = 8). Primary outcomes were gestational weight gain (GWG), infant birth weight, complications at delivery and a composite outcomes score. Secondary outcomes included type of delivery, prematurity, small- for-gestational-age (SGA) or large-for-gestational-age (LGA) infants, macrosomia, Apgar score, insulin use, depression, respiratory quotient (RQ), resting metabolic rate (RMR) and middle-upper arm circumference (MUAC). GWG differed between intervention groups (LED median: 12.0 kg; VLED: 5.9 kg). No differences were noted in the type of delivery, infant birth weight, composite score, prevalence of prematurity, depression, RQ, Apgar score, MUAC, or insulin use among the four groups. Regarding components of the composite score, most infants (88.4%) were appropriate-for-gestational age (AGA) and born at a gestational age of 37–42 weeks (95.3%). With respect to the mothers, 9.3% experienced complications at delivery, with the majority being allocated at the VLED + exercise arm (p < 0.03). The composite score was low (range 0–2.5) for all mother-infant pairs, indicating a “risk-free” pregnancy outcome. The results indicate that adherence to a LED or VLED induces similar maternal, infant and obstetrics outcomes.

Hepatokine levels during the first or early second trimester of pregnancy and the subsequent risk of gestational diabetes mellitus: a systematic review and meta-analysis

PURPOSE

The relationship between hepatokine levels during the first or early second trimester of pregnancy and the subsequent risk of gestational diabetes mellitus (GDM) have been studied extensively. However, conclusions remain debateable whether hepatokines are potential markers of GDM. We conducted a meta-analysis of published articles to understand the association between circulating levels of selected hepatokines (including FGF21, fetuin-A, afamin, adropin, ficolin-3, selenoprotein P, ANGPTL4 and AGF) and the risk of GDM.

MATERIALS AND METHODS

We searched the PubMed, Embase, Cochrane Library and Web of Science databases for studies published before January 2021 that examined the association between hepatokines and GDM (Prospero Registration# CRD42020191408). The quality was assessed by the Newcastle-Ottawa Scale (NOS). Pooled standard mean differences (SMDs) and weighted mean differences (WMDs) with 95% confidence intervals (CIs) were used to compare the levels of hepatokines in different groups using fixed effects or random effects models. Meta-regression analysis and publication bias were conducted in accordance with standard methods. The trim-fill adjustment method was used to further assess the possible effect of publication bias. Sensitivity analysis was performed by omitting each study one at a time.

RESULTS

The meta-analysis included 31 observational studies relating hepatokine levels to GDM in 4729 participants (1908 GDM, 2821 non-GDM). Serum FGF21 levels in patients with GDM were higher than those in healthy pregnant women during the second trimester and after delivery (SMD 0.89, [95% CI] 0.01-1.78 for the second trimester; SMD 1.42, [95% CI] 0.86-1.98 for after delivery). The serum levels of afamin in patients with GDM were significantly higher than those in healthy pregnant women during the first trimester and before pregnancy (SMD 0.51, [95% CI] 0.15-0.86 for first trimester; SMD 0.97, [95% CI] 0.45-1.50 for before pregnancy). Serum adropin levels in patients with GDM were higher than those in healthy pregnant women during the first and third trimesters of pregnancy (SMD 4.26, [95% CI] 3.30-5.23 for the first trimester; SMD 4.02, [95% CI] 3.09-4.94 for the third trimester). The serum levels of ficolin-3 in GDM patients were higher than those in healthy pregnant women during the second and third trimesters of pregnancy (WMD 1.43, [95% CI] 0.91-1.96 for the second trimester; SMD 1.28, [95% CI] 0.72-1.84 for the third trimester). The serum AGF level of patients with GDM was higher than that of healthy pregnant women in the control group in the third trimester (WMD 61 [95% CI] 37.04-81.96). The serum levels of selenoprotein P in patients with GDM were higher than those in healthy pregnant women in the control group during the first trimester (WMD 7.09 [95% CI] 4.6-9.57).

CONCLUSIONS

Measurement of circulating hepatokines in the first or second trimester of pregnancy may improve the identification of women at risk of developing GDM later. Prospective evaluation of the combination of hepatokines and maternal characteristics for early identification of those who do and do not require OGTT is warranted. Additional well-designed prospective studies with longitudinal assessment of hepatokines during pregnancy are needed to understand the trajectories and dynamic associations of hepatokines with GDM risk.

Newborn Adiposity and Cord Blood C-Peptide as Mediators of the Maternal Metabolic Environment and Childhood Adiposity

OBJECTIVE

Excessive childhood adiposity is a risk factor for adverse metabolic health. The objective was to investigate associations of newborn body composition and cord C-peptide with childhood anthropometrics and explore whether these newborn measures mediate associations of maternal midpregnancy glucose and BMI with childhood adiposity.

RESEARCH DESIGN AND METHODS

Data on mother/offspring pairs (N = 4,832) from the epidemiological Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Study and HAPO Follow-up Study (HAPO FUS) were analyzed. Linear regression was used to study associations between newborn and childhood anthropometrics. Structural equation modeling was used to explore newborn anthropometric measures as potential mediators of the associations of maternal BMI and glucose during pregnancy with childhood anthropometric outcomes.

RESULTS

In models including maternal glucose and BMI adjustments, newborn adiposity as measured by the sum of skinfolds was associated with child outcomes (adjusted mean difference, 95% CI, P value) BMI (0.26, 0.12-0.39, <0.001), BMI z-score (0.072, 0.033-0.11, <0.001), fat mass (kg) (0.51, 0.26-0.76, <0.001), percentage of body fat (0.61, 0.27-0.95, <0.001), and sum of skinfolds (mm) (1.14, 0.43-1.86, 0.0017). Structural equation models demonstrated significant mediation by newborn sum of skinfolds and cord C-peptide of maternal BMI effects on childhood BMI (proportion of total effect 2.5% and 1%, respectively), fat mass (3.1%, 1.2%), percentage of body fat (3.6%, 1.8%), and sum of skinfolds (2.9%, 1.8%), and significant mediation by newborn sum of skinfolds and cord C-peptide of maternal glucose effects on child fat mass (proportion of total association 22.0% and 21.0%, respectively), percentage of body fat (15.0%, 18.0%), and sum of skinfolds (15.0%, 20.0%).

CONCLUSIONS

Newborn adiposity is independently associated with childhood adiposity and, along with fetal hyperinsulinemia, mediates, in part, associations of maternal glucose and BMI with childhood adiposity.

The Need for Personalized Risk-Stratified Approaches to Treatment for Gestational Diabetes: A Narrative Review

Gestational diabetes mellitus (GDM) is common and is associated with an increased risk of adverse pregnancy outcomes. However, the prevailing one-size-fits-all approach that treats all women with GDM as having equivalent risk needs revision, given the clinical heterogeneity of GDM, the limitations of a population-based approach to risk, and the need to move beyond a glucocentric focus to address other intersecting risk factors. To address these challenges, we propose using a clinical prediction model for adverse pregnancy outcomes to guide risk-stratified approaches to treatment tailored to the individual needs of women with GDM. This will allow preventative and therapeutic interventions to be delivered to those who will maximally benefit, sparing expense, and harm for those at a lower risk.

Attenuated early pregnancy weight gain by prenatal lifestyle interventions does not prevent gestational diabetes in the LIFE-Moms consortium

AIMS

To examine the effect of lifestyle (diet and physical activity) interventions on the prevalence of GDM, considering the method of GDM ascertainment and its association with early pregnancy characteristics and maternal and neonatal outcomes in the LIFE-Moms consortium.

METHODS

LIFE-Moms evaluated the effects of lifestyle interventions to optimize gestational weight gain in 1148 pregnant women with BMI ≥ 25 kg/m2 and without known diabetes at enrollment, compared with standard care. GDM was assessed between 24 and 31-weeks gestation by a 2-hour, 75-gram OGTT or by local clinical practice standards.

RESULTS

Lifestyle interventions initiated prior to 16 weeks reduced early excess GWG compared with standard care (0.35 ± 0.24 vs 0.43 ± 0.26 kg per week, p=<0.0001) but did not affect GDM diagnosis (11.1% vs 11.6%, p = 0.91). Using the 75-gram, 2-hour OGTT, 13. 0% of standard care and 11.0% of the intervention group had GDM by the IADPSG criteria (p = 0.45). The 'type of diagnostic test' did not change the result (p = 0.86). Women who developed GDM were significantly heavier, more likely to have obesity, and more likely to have dysglycemia at baseline.

CONCLUSION

Moderate-to-high intensity lifestyle interventions grounded in behavior change theory initiated between 9 and 16-weeks gestation did not affect the prevalence of GDM despite reducing early GWG. CLINICALTRIALS.GOV: NCT01545934, NCT01616147, NCT01771133, NCT01631747, NCT01768793, NCT01610752, NCT01812694.

Association of high maternal triglyceride levels early and late in pregnancy with adverse outcomes: A retrospective cohort study

BACKGROUND

Excess maternal triglyceride (mTG) exposure during early or late pregnancy increases risks of adverse pregnancy outcomes. However, it is inconclusive whether persistently high maternal triglyceride during whole pregnancy has more negative associations.

OBJECTIVE

To explore whether persistently high maternal triglyceride (mTG) levels from early to late pregnancy further increases the risk of adverse pregnancy outcomes.

METHODS

We included 12,715 women who had a singleton birth and who underwent routine serum lipid screenings in both early (9-13 weeks) and late (28-42 weeks) pregnancy during May 2018 to July 2019 in a university-based maternity center. Risks for gestational diabetes mellitus (GDM), preeclampsia, preterm delivery, small/large for gestational age (LGA) were estimated.

RESULTS

Elevated mTG levels during early pregnancy were associated with increased risks of preterm delivery (AOR, 1.52; 95% CI, 1.21 to 1.90), preeclampsia (1.75; 1.29 to 2.36), gestational diabetes mellitus (1.95; 1.69 to 2.25), and LGA (1.28; 1.12 to 1.46). Compared with those with low mTG levels both in the 1st and 3rd trimesters, persistently high mTG levels increased the risks of preeclampsia (2.53; 1.66 to 3.84), GDM (1.97; 1.57 to 2.47), and LGA (1.68; 1.37 to 2.07). However, persistently high mTG levels only slightly increased risk of LGA when compared with high mTG levels during the 1st trimester alone (1.34, 1.01 to 1.77).

CONCLUSIONS

Elevated mTG levels during early pregnancy not in late pregnancy could be the crucial risk factor associated with adverse pregnancy outcomes. These results suggest the importance of lipid screenings and preventions during early pregnancy, which may help to improve pregnancy outcomes.

A Review of the Pathophysiology and Management of Diabetes in Pregnancy

Diabetes is a common metabolic complication of pregnancy and affected women fall into two subgroups: women with pre-existing diabetes and those with gestational diabetes mellitus (GDM). When pregnancy is affected by diabetes, both mother and infant are at increased risk for multiple adverse outcomes. A multidisciplinary approach to care before, during, and after pregnancy is effective in reducing these risks. The PubMed database was searched for English language studies and guidelines relating to diabetes in pregnancy. The following search terms were used alone and in combination: diabetes, pregnancy, gestational diabetes, GDM, prepregnancy, and preconception. A date restriction was not applied. Results were reviewed by the authors and selected for inclusion based on relevance to the topic. Additional articles were identified by manually searching reference lists of included articles. Using data from this search we herein summarize the evidence relating to pathophysiology and management of diabetes in pregnancy. We discuss areas of controversy including the method and timing of diagnosis of GDM, and choice of pharmacologic agents to treat hyperglycemia during pregnancy. Therefore, this review is intended to serve as a practical guide for clinicians who are caring for women with diabetes and their infants.

Dysglycemia in Pregnancy and Maternal/Fetal Outcomes

Maternal dysglycemia-including diabetes, impaired glucose tolerance, and impaired fasting glucose-affects one in six pregnancies worldwide and represents a significant health risk to the mother and the fetus. Maternal dysglycemia is an independent risk factor for perinatal mortality, major congenital anomalies, and miscarriages. Furthermore, it increases the longer-term risk of type 2 diabetes mellitus, metabolic syndrome, cardiovascular morbidity, malignancies, and ophthalmic, psychiatric, and renal diseases in the mother. The most commonly encountered form of maternal dysglycemia is gestational diabetes. Currently, international consensus does not exist for diagnostic criteria defining gestational diabetes at 24-28 weeks gestation, and potential diagnostic glucose thresholds earlier in gestation require further investigation. Likewise, recommendations regarding the timing and modality (e.g., lifestyle or pharmacological) of treatment vary greatly. Because a precise diagnosis determines the appropriate treatment and outcome of the pregnancy, it is imperative that a better definition of maternal dysglycemia and its treatment be achieved. This article will address some of the controversies related to diagnosing and managing maternal dysglycemia. In addition, the article will discuss the impact of maternal dysglycemia on complications experienced by the mother and infant, both at birth and in later life.

HbA1c during early pregnancy reflects beta-cell dysfunction in women developing GDM

INTRODUCTION

It is of current interest to assess eligibility of hemoglobin A1c (HbA1c) as a screening tool for earlier identification of women with risk for more severe hyperglycemia in pregnancy but data regarding accuracy are controversial. We aimed to evaluate if HbA1c mirrors pathophysiological precursors of glucose intolerance in early pregnancy that characterize women who develop gestational diabetes mellitus (GDM).

RESEARCH DESIGN AND METHODS

220 pregnant women underwent an HbA1c measurement as well as an oral glucose tolerance test (OGTT) with multiple measurements of glucose, insulin and C-peptide for evaluation of insulin sensitivity and beta-cell function at 16th gestational week (IQR: 14-18). Clinical follow-ups were performed until end of pregnancy.

RESULTS

Increased maternal HbA1c ≥5.7% (39 mmol/mol) corresponding to pre-diabetes outside of pregnancy was associated with altered glucose dynamics during the OGTT. Pregnancies with early HbA1c ≥5.7% showed higher fasting (90.4±13.2 vs 79.7±7.2 mg/dL, p<0.001), mean (145.6±31.4 vs 116.2±21.4 mg/dL, p<0.001) as well as maximum glucose concentrations and tended to a delay in reaching the maximum glucose level compared with those with normal-range HbA1c (186.5±42.6 vs 147.8±30.1 mg/dL, p<0.001). Women with increased HbA1c showed impaired beta-cell function and differences in disposition index independent of body mass index status. We observed a high specificity for the HbA1c cut-off of 5.7% for GDM manifestation (0.96, 95% CI 0.91 to 0.98) or need of glucose-lowering medication (0.95, 95% CI 0.90 to 0.98) although overall predictive accuracy was moderate to fair. Further, elevated HbA1c was associated with higher risk for delivering large-for-gestational-age infants, also after adjustment for GDM status (OR 4.4, 95% CI 1.2 to 15.0, p=0.018).

CONCLUSIONS

HbA1c measured before recommended routine screening period reflects early pathophysiological derangements in beta-cell function and glucose disposal that are characteristic of GDM development and may be useful in early risk stratification.

Performance of early pregnancy HbA1c for predicting gestational diabetes mellitus and adverse pregnancy outcomes in obese European women

AIMS

To investigate the performance of early pregnancy HbA_1c for predicting gestational diabetes mellitus (GDM) and adverse pregnancy outcomes in obese women.

METHODS

Post hoc analysis using data from the Vitamin D And Lifestyle Intervention for GDM prevention trials conducted across 9 European countries (2012-2014). Pregnant women (BMI ≥ 29 kg/m²) underwent a baseline HbA_1c and oral glucose tolerance tests at < 20 weeks, 24-28 weeks, and 35-37 weeks. Women with GDM were referred for treatment.

RESULTS

Among the 869 women tested, the prevalence of GDM was 25.9% before 20 weeks, with a further 8.6% at 24-28 weeks. The areas under the curves for HbA_1c at the two time points were 0.55 (0.50-0.59) and 0.54 (0.47-0.61), respectively. An early HbA_1c ≥ 5.7% (39 mmol/mol) (N = 111) showed low sensitivity (18.2%) with 89.1% specificity for GDM before 20 weeks, at 24-28 weeks (sensitivity of 8.0% and specificity of 88.6% after excluding early GDM), and throughout gestation (sensitivity of 15.9% and specificity of 89.4%). The ≥ 5.7% (39 mmol/mol) threshold was significantly associated with concurrent GDM before 20 weeks (adjusted OR (aOR) 2.77(1.39-5.51)) and throughout gestation (aOR 1.72 (1.02-2.89)), but not adverse pregnancy outcomes.

CONCLUSIONS

Early pregnancy HbA_1c is of limited use for predicting either GDM or adverse outcomes in overweight/obese European women.

Fetal macrosomia in a Hispanic/Latinx predominant cohort and altered expressions of genes related to placental lipid transport and metabolism

Fetal overgrowth, termed fetal macrosomia when birth weight is greater than 4000 grams, is the major concern in the treatment of gestational diabetes mellitus (GDM). However, to date, the underlying mechanisms of fetal macrosomia have not been understood completely. Placental lipid metabolism is emerging as a critical player in fetal growth. In this study, we hypothesized that fatty acid transport and metabolism in the placental tissue was impaired in GDM women, dependent on fetal sex. To test this hypothesis, we analyzed the incidence of GDM, fetal macrosomia, and obesity in a large cohort consisting of 17995 pregnant subjects and majority of subjects being Hispanic/Latinx, and investigated expression of genes related to lipid transport and metabolism in placenta from obese women with or without GDM, and with or without fetal macrosomia. The main findings include: 1) There is a higher incidence of GDM and obesity in Hispanic subjects compared to non-Hispanic subjects, but not fetal macrosomia; 2) Expressions of most of genes related to placental lipid transport and metabolism are not altered by the presence of GDM, fetal macrosomia, or fetal sex; 3) Expression of FABP4 is increased in obese women with GDM and fetal macrosomia, and this occurred in male placentas; 4) Expression of LPL is decreased in obese women with GDM despite fetal macrosomia, and this occurred in male placentas; 5) Expression of ANGPTL3 is decreased in obese women with GDM and fetal macrosomia, but is not altered when fetal sex is included in the analysis. This study indicates that there is race disparity in GDM with higher incidence of GDM in obese Hispanic women, although fetal macrosomia disparity is not present. Moreover, altered placental lipid transport may contribute to fetal overgrowth in obese women with GDM.

Early gestational diabetes screening in obese women: a randomized controlled trial

BACKGROUND

Although in 2013 the American College of Obstetricians and Gynecologists recommended early screening for gestational diabetes in obese women, no studies demonstrate an improvement in perinatal outcomes with this strategy.

OBJECTIVE

We sought to determine whether early screening for gestational diabetes improves perinatal outcomes in obese women.

MATERIALS AND METHODS

Randomized controlled trial comparing early gestational diabetes screening (14-20 weeks) to routine screening (24-28 weeks) in obese women (body mass index ≥30 kg/m2) at 2 tertiary care centers in the United States. Screening was performed using a 50-g, 1-hour glucose challenge test followed by a 100-g, 3-hour glucose tolerance test if the initial screen was ≥135 mg/dL. Gestational diabetes was diagnosed using Carpenter-Coustan criteria. Women not diagnosed at 14 to 20 weeks were rescreened at 24 to 28 weeks. Exclusion criteria were pre-existing diabetes, major medical illness, bariatric surgery, and prior cesarean delivery. The primary outcome was a composite of macrosomia (>4000 g), primary cesarean delivery, hypertensive disease of pregnancy, shoulder dystocia, neonatal hyperbilirubinemia, and neonatal hypoglycemia (assessed within 48 hours of birth).

RESULTS

A total of 962 women were randomized, and outcomes were available for 922. Of these 922 women, 459 (49.8%) were assigned to early screen and 463 (50.2%) to routine screen. Baseline characteristics were balanced between groups. In the early screening group, 69 (15.0%; 95% confidence interval, 11.9-18.6%) were diagnosed with gestational diabetes: 29 (6.3%; 95% confidence interval, 4.3-8.9%) at <20 weeks and 40 (8.7%; 95% confidence interval, 6.3-11.7%) at >24 weeks. Of those randomized to routine screening, 56 (12.1%; 95% confidence interval, 9.3-15.4%) had gestational diabetes. Early screening did not reduce the incidence of the primary outcome (56.9% in the early screen versus 50.8% in the routine screen, P = .07; relative risk, 1.12; 95% confidence interval, 0.99-1.26).

CONCLUSION

Early screening for gestational diabetes in obese women did not reduce the composite perinatal outcome.

Timing of Gestational Diabetes Diagnosis by Maternal Obesity Status: Impact on Gestational Weight Gain in a Diverse Population

Background: We hypothesized that earlier gestational diabetes mellitus (GDM) diagnosis and treatment of high-risk women would reduce gestational weight gain (GWG) in the first trimester and overall. Materials and Methods: We evaluated timing of GDM diagnosis among 5,391 pregnant women who delivered singleton births 2010-2013 in a large diverse health maintenance organization (HMO). All GDM screening was by the same oral glucose tolerance testing protocol; GDM treatment protocols were also consistent irrespective of timing of diagnosis. Women without risk factors were universally screened at 24-28 weeks gestation (Usual). Early screening was recommended in obese and other high-risk women at the first prenatal visit; those who screened negative Early were rescreened at 24-28 weeks (Early+Usual). Results: Average GWG for all women was 12.8 kg; 10.7% of women were diagnosed with GDM. Average GWG for all women diagnosed with GDM was 10.7 kg, adjusted for gestational age. Women with EarlyGDM averaged 2.4 kg less GWG than women diagnosed with UsualGDM (p < 0.0001). Among obese women, only women diagnosed with EarlyGDM averaged overall GWG within Institute of Medicine (IOM) weight guidelines (mean 8.1 kg) and were weight neutral in the first trimester (-0.2 kg). Overall, 43% of all pregnant women exceeded IOM GWG guidelines (gained more total weight than recommended); 60% of obese women exceeded guidelines. Obese women diagnosed with GDM were less likely to exceed IOM guidelines if diagnosed earlier in pregnancy (35% EarlyGDM vs. 59% UsualGDM exceeded guidelines, p < 0.0001). Conclusion: Our results suggest that EarlyGDM diagnosis (and thus treatment) in high-risk women is beneficial for optimizing GWG.

Oral glucose tolerance test results in early pregnancy: A Finnish population-based cohort study

AIMS

To analyze early-pregnancy oral glucose tolerance test (OGTT) results and differences between early- and late-pregnancy OGTT results in a population-based cohort.

METHODS

From 3/2013 to 12/2016, pregnant women in South Karelia, Finland, were invited to undergo a 2-hour 75 g OGTT at 12-16 weeks' gestation (OGTT1) and, if normal, repeat testing at 24-28 weeks (OGTT2). Early and late gestational diabetes (GDM) were diagnosed using the same nationally endorsed criteria (fasting [FPG], 1- or 2-hour plasma glucose ≥5.3, ≥10.0 or ≥8.6 mmol/L, respectively).

RESULTS

In OGTT1 (n = 1401), the mean (SD) FPG, 1- and 2-hour values were 4.85 (0.34), 6.63 (1.73) and 5.60 (1.28) mmol/L, respectively. Early GDM was diagnosed in 209 (14.9%). In OGTT2 (n = 1067), late GDM was diagnosed in 114 (10.6%). In women without GDM (n = 953), the mean FPG values were higher and post-load values lower in OGTT1 vs. OGTT2. No interaction effects of gestational timepoint and maternal BMI on OGTT results were detected, except for the 2-hour value. In women with late GDM, both mean FPG and post-load values were lower in OGTT1 vs. OGTT2. Results were similar employing the IADPSG GDM criteria.

CONCLUSIONS

Our findings suggest that gestational-age specific OGTT thresholds for early GDM diagnosis need to be generated.

Plasma Glycated CD59 Predicts Early Gestational Diabetes and Large for Gestational Age Newborns

CONTEXT

Gestational diabetes mellitus (GDM) diagnosed in early pregnancy is a health care challenge because it increases the risk of adverse outcomes. Plasma-glycated CD59 (pGCD59) is an emerging biomarker for diabetes and GDM. The aim of this study was to assess the performance of pGCD59 as a biomarker of early GDM and its association with delivering a large for gestational age (LGA) infant.

OBJECTIVES

To assess the performance of pGCD59 to identify women with GDM in early pregnancy (GDM < 20) and assess the association of pGCD59 with LGA and potentially others adverse neonatal outcomes linked to GDM.

METHODS

Blood levels of pGCD59 were measured in samples from 693 obese women (body mass index > 29) undergoing a 75-g, 2-hour oral glucose tolerance test (OGTT) at <20 weeks' gestation in the Vitamin D and Lifestyle Intervention study: the main analyses included 486 subjects who had normal glucose tolerance throughout the pregnancy, 207 who met criteria for GDM at <20 weeks, and 77 diagnosed with GDM at pregnancy weeks 24 through 28. Reference tests were 75-g, 2-hour OGTT adjudicated based on International Association of Diabetes and Pregnancy Study Group criteria. The index test was a pGCD59 ELISA.

RESULTS

Mean pGCD59 levels were significantly higher (P < 0.001) in women with GDM < 20 (3.9 ± 1.1 standard peptide units [SPU]) than in those without (2.7 ± 0.7 SPU). pGCD59 accurately identified GDM in early pregnancy with an area under the curve receiver operating characteristic curves of 0.86 (95% confidence interval [CI], 0.83-0.90). One-unit increase in maternal pGCD59 level was associated with 36% increased odds of delivering an LGA infant (odds ratio for LGA vs non-LGA infant: 1.4; 95% CI, 1.1-1.8; P = 0.016).

CONCLUSION

Our results indicate that pGCD59 is a simple and accurate biomarker for detection of GDM in early pregnancy and risk assessment of LGA.

The Use of Non-insulin Agents in Gestational Diabetes: Clinical Considerations in Tailoring Therapy

PURPOSE OF REVIEW

To assess evidence to date for use of non-insulin agents in treatment of gestational diabetes mellitus.

RECENT FINDINGS

There has been increasing interest in the use of non-insulin agents, primarily metformin and glyburide (which both cross the placenta). Metformin has been associated with less maternal weight gain; however, recent studies have shown a trend toward increased weight in offspring exposed to metformin in utero. Glyburide has been associated with increased neonatal hypoglycemia. Glycemic control during pregnancy is essential to optimize both maternal and fetal outcomes. There are a myriad of factors to consider when designing treatment programs including patient preference, phenotype, and glucose patterns. While insulin is typically recommended as first-line, some women refuse or cannot afford insulin and in those cases, non-insulin agents may be used. Further studies are needed to assess treatment in pregnancy, perinatal outcomes, and particularly long-term metabolic profiles in mothers and offspring.

Hyperglycemia During Pregnancy and Long-Term Offspring Outcomes

PURPOSE OF REVIEW

This review will focus on the long-term outcomes in offspring exposed to in utero hyperglycemia and gestational diabetes (GDM), including obesity, adiposity, glucose metabolism, hypertension, hyperlipidemia, nonalcoholic fatty liver disease, and puberty.

RECENT FINDINGS

There is evidence, mostly from observational studies, that offspring of GDM mothers have increased risk of obesity, increased adiposity, disorders of glucose metabolism (insulin resistance and type 2 diabetes), and hypertension. In contrast, evidence from the two intervention studies of treatment of mild GDM and childhood measures of BMI, adiposity, and glucose tolerance do not demonstrate that GDM treatment significantly reduces adverse childhood metabolic outcomes. Thus, more evidence is needed to understand the impact of maternal GDM on offspring's adiposity, glucose metabolism, lipid metabolism, risk of fatty liver disease, and pubertal onset. Offspring of GDM mothers may have increased risk for metabolic and cardiovascular complications. Targeting this group for intervention studies to prevent obesity and disorders of glucose metabolism is one potential strategy to prevent adverse metabolic health outcomes.

A randomized pragmatic clinical trial of gestational diabetes screening (ScreenR2GDM): Study design, baseline characteristics, and protocol adherence

BACKGROUND

ScreenR2GDM is a pragmatic randomized clinical trial designed to investigate if one of two gestational diabetes (GDM) screening and treatment protocols results in improved outcomes in the context of standard clinical care.

METHODS

Pregnant women are randomized to one of two GDM screening strategies: 1-step: 2-h, 75 g, oral glucose tolerance test (OGTT) or 2-step: 1-h, 50 g glucose challenge test (GCT) followed by 3-h, 100 g OGTT if GCT-positive. Providers are prompted within the electronic medical record to order the assigned test but were given the option to order the alternate test. Collected data include maternal and pregnancy characteristics, GDM testing, and outcomes for mother and newborn. We describe the study design and baseline characteristics and evaluate characteristics associated with adhering to the randomized protocol.

RESULTS

Baseline characteristics of the 23,792 randomized pregnancies were comparable between the two groups. Adherence to assigned test differed between the two strategies: 66.1% for 1-step and 91.7% for 2-step (p < .0001). 27% of the women randomized to receive the 1-step completed the 2-step test vs 2% randomized to the 2-step who completed the 1-step (p < .0001). Patient characteristics related to adherence included obesity, age, prior GDM, Medicaid insurance, race and nulliparity. Clinician characteristics related to adherence included provider type, age and gender.

CONCLUSIONS

Both patient and provider characteristics were related to adherence to the randomized GDM screening protocol. Analytical techniques that incorporate these findings into the formal evaluation of the two protocols on GDM-associated outcomes will be necessary to account for potential biases introduced by non-adherence.

Intensive glycemic control in gestational diabetes mellitus: a randomized controlled clinical feasibility trial

BACKGROUND

Overweight and obese women with gestational diabetes mellitus are at increased risk for adverse perinatal outcomes, and they are also more likely to have suboptimal glycemic control. However, there is a paucity of data evaluating whether lower glycemic targets could improve outcomes.

OBJECTIVE

To evaluate the feasibility of intensive glycemic control in overweight and obese women with gestational diabetes mellitus.

MATERIALS AND METHODS

We randomized 60 overweight or obese women with gestational diabetes mellitus, diagnosed between 12 and 32 weeks' gestation to either intensive (fasting <90 mg/dL, 1 hour postprandial <120 mg/dL) or standard (fasting <95 mg/dL, 1 ho postprandial <140 mg/dL) glycemic targets. Maternal glucose was assessed in 2 ways: blinded continuous glucose monitors, worn for 5 days at 2 time points (at 12-32 weeks and again at 32-36 weeks), and self-monitored glucose measurement 4 times per day. All women underwent standardized dietary counseling, and medical therapy was prescribed as needed to achieve glycemic control.

RESULTS

Between December 2015 and December 2017, we randomized 60 women to either intensive (n = 30) or standard (n = 30) glycemic control. Baseline characteristics including maternal age, body mass index, and gestational age at diagnosis were similar between the intensive and standard groups. Medical therapy was more common in women in the intensive group than those in the standard group (83 vs 57%, P = .02). Women in the intensive glycemic control group had lower glucose values as assessed by continuous glucose monitors at including 24-hour mean (-8.1; 95% confidence interval, -12.0 to -4.3 mg/dL; P < .0001) and 1-h postprandial (-11.8; 95% confidence interval, -19.7 to -3.9 mg/dL, P = .004) values. Hypoglycemia <60 mg/dL was uncommon and did not differ between groups.

CONCLUSION

Intensive glycemic targets can be used in overweight and obese women with minimal hypoglycemia, and this approach results in improved glycemic control when compared to standard glycemic targets. Further studies are needed to determine whether intensive glycemic targets can improve maternal and neonatal outcomes in high-risk women with gestational diabetes mellitus.

CLINICAL TRIAL IDENTIFIER

NCT02530866; clinicaltrials.gov.

Optimal management of gestational diabetes

BACKGROUND

Gestational diabetes mellitus (GDM) is highly prevalent and has both short- and long-term implications for mother and infant.

SOURCES OF DATA

Literature search using PubMed with keywords 'Gestational diabetes' and 'diabetes in pregnancy' together with published papers known to the authors.

AREAS OF AGREEMENT

The cornerstone of management is medical nutrition therapy with regular self-monitoring of capillary blood glucose levels and intensification of therapy if glycaemic goals are not achieved. Post-partum, annual assessment for type 2 diabetes is recommended.

AREAS OF CONTROVERSY

Diagnostic criteria and new biomarkers for GDM and the clinical and economic benefits of treating women with milder levels of glucose intolerance during pregnancy.

GROWING POINTS

Women with GDM are a heterogeneous group with varying degrees of insulin resistance and beta cell dysfunction.

AREAS TIMELY FOR DEVELOPING RESEARCH

Development of alternative diagnostic markers and application of novel technologies for GDM management.

d-GDM: A mobile diagnostic decision support system for gestational diabetes

OBJECTIVE

The aim of the study is to describe a portable and convenient software to facilitate the diagnostics of gestational (GDM) and pre-gestational diabetes (PGDM).

MATERIALS AND METHODS

An open source software, d-GDM, was developed in Java. The integrated development environment Android Studio was used as the Android operational system. The software for GDM diagnosis uses the criteria endorsed by the International Association of Diabetes and Pregnancy Study Group, modified by the World Health Organization.

RESULTS

GDM diagnosis criteria is not simple to follow, therefore, errors or inconsistencies in diagnosis are expected and could delay the appropriate treatment. The d-GDM, was developed to assist GDM diagnosis with precision and consistency diagnostic reports. The open source software can be manipulated conveniently. The operator requires information regarding the gestational period and selects the appropriate glycaemic marker options from the menu. During operation, pressing the button "diagnosticar" on the screen will present the diagnosis and information for the follow up. d-GDM is available in Portuguese or English and can be downloaded from the Google PlayStore. A responsive web version of d-GDM is also available. The usefulness and accuracy of d-GDM was verify by field tests involving 22 subjects and 5 mobile phone brands. The approval regards user-friendliness and efficiency were 95% or higher. The GDM diagnosis were 100% correct, in this pilot test. d-GDM is a user-friendly, free software for diagnosis that was developed for mobile devices. It has the potential to contribute and facilitate the diagnosis of gestational diabetes for healthcare professionals.

Gestational Diabetes Mellitus

Although it has been accepted for decades that women with gestational diabetes mellitus (GDM) are at high risk for future development of type 2 diabetes, vigorous debate regarding the value of detecting and treating GDM has persisted into the twenty-first century. Although results from 2 randomized trials provide strong evidence that treating GDM reduces adverse perinatal outcomes, it remains to be determined whether treatment impacts long-term offspring outcomes. Insulin is the first-line pharmacologic treatment and is added when glycemic goals are not met with nutritional modifications. Oral agent use is controversial, as data on long-term offspring outcomes are lacking.