Lower versus Higher Glycemic Criteria for Diagnosis of Gestational Diabetes

Diagnosis and Treatment of Hyperglycemia in Pregnancy: Type 2 Diabetes Mellitus and Gestational Diabetes

Hyperglycemia in pregnancy due to pre-existing Type 2 diabetes mellitus (T2DM) and gestational diabetes mellitus (GDM) is rising globally with increasing rates of risk factors for metabolic disease. This review summarizes current evidence and recommendations from national and international guidelines for diagnosis and management of T2DM and GDM to optimize maternal and neonatal outcomes.

Effect of treatment for early gestational diabetes mellitus on neonatal respiratory distress: A secondary analysis of the TOBOGM study

OBJECTIVE

To identify factors associated with neonatal respiratory distress (NRD) in early Gestational diabetes mellitus (eGDM).

DESIGN

Nested case-control analysis of the TOBOGM trial.

SETTING

Seventeen hospitals: Australia, Sweden, Austria and India.

POPULATION

Pregnant women, <20 weeks' gestation, singleton, GDM risk factors.

METHODS

Women with GDM risk factors completed an oral glucose tolerance test (OGTT) before 20 weeks: those with eGDM (WHO-2013 criteria) were randomised to immediate or deferred GDM treatment. Logistic regression compared pregnancies with/without NRD, and in pregnancies with NRD, those with/without high-dependency nursery admission for ≤24 h with those admitted for >24 h. Comparisons were adjusted for age, pre-pregnancy body mass index, ethnicity, smoking, primigravity, education and site. Adjusted odds ratios (95% CI) are reported.

MAIN OUTCOME MEASURES

NRD definition: ≥4 h of respiratory support (supplemental oxygen or supported ventilation) postpartum. Respiratory distress syndrome (RDS): Supported ventilation and ≥24 h nursery stay.

RESULTS

Ninety-nine (12.5%) of 793 infants had NRD; incidence halved (0.50, 0.31-0.79) if GDM treatment was started early. NRD was associated with Caesarean section (2.31, 1.42-3.76), large for gestational age (LGA) (1.83, 1.09-3.08) and shorter gestation (0.95, 0.93-0.97 per day longer). Among NRD infants, >24 h nursery-stay was associated with higher OGTT 1-h glucose (1.38, 1.08-1.76 per mmol/L). Fifteen (2.0%) infants had RDS.

CONCLUSIONS

Identifying and treating eGDM reduces NRD risk. NRD is more likely with Caesarean section, LGA and shorter gestation. Further studies are needed to understand the mechanisms behind this eGDM complication and any long-term effects.

Metabolic factors and perinatal outcomes among pregnant individuals with mild glucose intolerance

AIMS

Metabolic characteristics and outcomes were compared among pregnant individuals with varying levels of glucose intolerance.

METHODS

827 participants from a randomized clinical trial comparing the IADPSG and Carpenter Coustan Criteria were grouped as follows: normal glucose tolerance, mild glucose intolerance (100 g OGTT with one abnormal value) and treated GDM (diagnosed by Carpenter Coustan or IADPSG criteria). Differences in metabolic characteristics and perinatal outcomes were assessed using inverse probability of treatment weighting.

RESULTS

Mild glucose intolerance had lower insulin sensitivity and beta cell response than normal glucose tolerance, and similar findings to treated GDM. Small for gestational age (SGA) (OR 0.13, 95% CI 0.08-0.24) and neonatal composite morbidity were lower (OR 0.53, 95% CI 0.38-0.74), and maternal composite morbidity higher (OR 2.03, 95% CI 1.57-2.62) when comparing mild intolerance to normal glucose tolerance. Large for gestational age (OR 3.42 95% CI 1.39-8.41) was higher while SGA (OR 0.21, 95% CI 0.05-0.81) and neonatal composite morbidity (OR 0.31, 95% CI 0.17-0.57) were lower with mild glucose intolerance compared to treated GDM.

CONCLUSIONS

Mild glucose intolerance has a similar metabolic profile to treated GDM, and outcome differences are likely related to knowledge of diagnosis and treatment.

CLINICAL TRIALS REGISTRY

NCT02309138.

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.

Changing diagnostic criteria for gestational diabetes (CDC4G) in Sweden: A stepped wedge cluster randomised trial

BACKGROUND

The World Health Organisation (WHO) 2013 diagnostic criteria for gestational diabetes mellitus (GDM) has been criticised due to the limited evidence of benefits on pregnancy outcomes in different populations when switching from previously higher glycemic thresholds to the lower WHO-2013 diagnostic criteria. The aim of this study was to determine whether the switch from previous Swedish (SWE-GDM) to the WHO-2013 GDM criteria in Sweden following risk factor-based screening improves pregnancy outcomes.

METHODS AND FINDINGS

A stepped wedge cluster randomised trial was performed between January 1 and December 31, 2018 in 11 clusters (17 delivery units) across Sweden, including all pregnancies under care and excluding preexisting diabetes, gastric bypass surgery, or multifetal pregnancies from the analysis. After implementation of uniform clinical and laboratory guidelines, a number of clusters were randomised to intervention (switch to WHO-2013 GDM criteria) each month from February to November 2018. The primary outcome was large for gestational age (LGA, defined as birth weight >90th percentile). Other secondary and prespecified outcomes included maternal and neonatal birth complications. Primary analysis was by modified intention to treat (mITT), excluding 3 clusters that were randomised before study start but were unable to implement the intervention. Prespecified subgroup analysis was undertaken among those discordant for the definition of GDM. Multilevel mixed regression models were used to compare outcome LGA between WHO-2013 and SWE-GDM groups adjusted for clusters, time periods, and potential confounders. Multiple imputation was used for missing potential confounding variables. In the mITT analysis, 47 080 pregnancies were included with 6 882 (14.6%) oral glucose tolerance tests (OGTTs) performed. The GDM prevalence increased from 595/22 797 (2.6%) to 1 591/24 283 (6.6%) after the intervention. In the mITT population, the switch was associated with no change in primary outcome LGA (2 790/24 209 (11.5%) versus 2 584/22 707 (11.4%)) producing an adjusted risk ratio (aRR) of 0.97 (95% confidence interval 0.91 to 1.02, p = 0.26). In the subgroup, the prevalence of LGA was 273/956 (28.8%) before and 278/1 239 (22.5%) after the switch, aRR 0.87 (95% CI 0.75 to 1.01, p = 0.076). No serious events were reported. Potential limitations of this trial are mainly due to the trial design, including failure to adhere to guidelines within and between the clusters and influences of unidentified temporal variations.

CONCLUSIONS

In this study, implementing the WHO-2013 criteria in Sweden with risk factor-based screening did not significantly reduce LGA prevalence defined as birth weight >90th percentile, in the total population, or in the subgroup discordant for the definition of GDM. Future studies are needed to evaluate the effects of treating different glucose thresholds during pregnancy in different populations, with different screening strategies and clinical management guidelines, to optimise women's and children's health in the short and long term.

TRIAL REGISTRATION

The trial is registered with ISRCTN (41918550).

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.

The WHO 2013 oral glucose tolerance test: The utility of isolated glucose measurements - A retrospective cohort study

OBJECTIVE

The WHO 2013 guidelines recommend screening for gestational diabetes mellitus (GDM) by 3-point oral glucose tolerance test (OGTT). The objective of this retrospective cohort study was to evaluate GDM diagnosed by an isolated high glucose.

STUDY DESIGN

We included pregnant women deemed at risk for GDM were offered GDM screening. We examined the records of 1939 consecutively screened pregnancies at two teaching hospitals in Amsterdam during 2016-2020. Using the WHO 2013 diagnostic criteria, we calculated the proportion of GDM cases diagnosed by isolated abnormal glucose values.

RESULTS

Among those screened in our high risk cohort, GDM incidence was 31.5%. Of the GDM diagnoses, 57.0% were based on an isolated fasting glucose value, 30.9% based on multiple raised glucose measurements, 7.4% on an isolated raised 2-hour glucose and 4.7% on an isolated raised 1-hour glucose. For 1-hour glucose, the number needed to screen was 67 persons for one additional GDM case.

CONCLUSION

The 1-hour glucose in the 3 point OGTT, as suggested by the WHO 2013 guidelines for GDM, contributes only small numbers of GDM cases and a high number needed to screen (67 for 1 additional case in a selective high risk GDM screening strategy), and is likely even less effective in universally screened populations.

Establishing novel diagnostic criteria for the glucose tolerance test for the diagnosis of gestational diabetes and gestational hyperglycemia

OBJECTIVE

To establish diagnostic criteria for the 75-g 2-h glucose tolerance test (GTT) to diagnose gestational diabetes and define the clinical entity of gestational hyperglycemia.

METHODS

A retrospective analysis was performed of the results from 500 patients who had a 75-g 1-h glucose challenge test (GCT) in early pregnancy as part of a two-step approach to screening and testing for gestational diabetes. The selected cohort was considered to have normal islet β-cell function, and upper glycemic levels of normal glucose tolerance in the third trimester were statistically calculated, taking the cutoff threshold values to be the diagnostic criteria for the 75-g 2-h GTT. Gestational hyperglycemia was diagnosed from the false-positive GCT result when ≥8.0 mmol/L (144 mg/dL).

RESULTS

The diagnostic criteria for the 75-g 2-h GTT were calculated as follows: fasting plasma glucose ≥5.4 mmol/L (97 mg/dL); 1-h plasma glucose ≥10.5 mmol/L (189 mg/dL); and 2-h plasma glucose ≥8.4 mmol/L (151 mg/dL). The new criteria confirmed a prevalence of gestational diabetes of 11.1% and gestational hyperglycemia of 13.6% in the study population.

CONCLUSION

Novel diagnostic criteria for the 75-g 2-h GTT were established by statistical analysis. This resulted in a more acceptable prevalence of gestational diabetes in our community and the false-positive GCT allowed the detection of gestational hyperglycemia.

Impact of Gestational Diabetes Detection Thresholds on Infant Growth and Body Composition: A Prospective Cohort Study Within a Randomized Trial

OBJECTIVE

Gestational diabetes mellitus (GDM) is associated with offspring metabolic disease, including childhood obesity, but causal mediators remain to be established. We assessed the impact of lower versus higher thresholds for detection and treatment of GDM on infant risk factors for obesity, including body composition, growth, nutrition, and appetite.

RESEARCH DESIGN AND METHODS

In this prospective cohort study within the Gestational Diabetes Mellitus Trial of Diagnostic Detection Thresholds (GEMS), pregnant women were randomly allocated to detection of GDM using the lower criteria of the International Association of Diabetes and Pregnancy Study Groups or higher New Zealand criteria (ACTRN12615000290594). Randomly selected control infants of women without GDM were compared with infants exposed to A) GDM by lower but not higher criteria, with usual treatment for diabetes in pregnancy; B) GDM by lower but not higher criteria, untreated; or C) GDM by higher criteria, treated. The primary outcome was whole-body fat mass at 5-6 months.

RESULTS

There were 760 infants enrolled, and 432 were assessed for the primary outcome. Fat mass was not significantly different between control infants (2.05 kg) and exposure groups: A) GDM by lower but not higher criteria, treated (1.96 kg), adjusted mean difference (aMD) -0.09 (95% CI -0.29, 0.10); B) GDM by lower but not higher criteria, untreated (1.94 kg), aMD -0.15 (95% CI -0.35, 0.06); and C) GDM detected and treated using higher thresholds (1.87 kg), aMD -0.17 (95% CI -0.37, 0.03).

CONCLUSIONS

GDM detected using lower but not higher criteria, was not associated with increased infant fat mass at 5-6 months, regardless of maternal treatment. GDM detected and treated using higher thresholds was also not associated with increased fat mass at 5-6 months.

Prevalence and treatment of gestational diabetes in Norway 2010-2020

AIMS

Estimate prevalence of gestational diabetes mellitus (GDM) and its treatment in Norway 2010-2020 and explore impact of new national GDM guidelines in 2017.

METHODS

We identified women giving birth in a nationwide cohort study using registers on births, prescriptions, education, primary and specialist care. For each year, we estimated prevalence of GDM overall, by BMI, age, education, and mother's birthplace; proportions of GDM pregnancies receiving pharmacological treatment; and distribution of the gestational week when GDM was diagnosed.

RESULTS

In 633,169 pregnancies, prevalence of GDM increased from 2.6 % in 2010 to 6.0 % in 2016, then stabilized. Similar patterns were seen across strata of BMI, age, education, and maternal birthplace, although prevalence was higher with higher BMI, higher age, lower education, and mothers born in Asia, Africa, or Middle East. The proportion of the GDM population pharmacologically treated increased from 11.6 % in 2010 to 13.6 % in 2016 and 31.6 % in 2020. GDM was diagnosed in recommended gestational week 24-28 in 19 % versus 45 % of GDM pregnancies in 2010 and 2020, respectively.

CONCLUSIONS

Both the proportion diagnosed with GDM within recommended time of screening, and who received pharmacological treatment, increased substantially following new guidelines in 2017. Prevalence of GDM increased from 2010 to 2016, then plateaued.

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).

Impact of COVID-19 mandatory lockdown on maternal gestational weight gain and neonatal macrosomia rate at an academic medical center in Israel

BACKGROUND

In an effort to prevent the spread of coronavirus disease 2019 (COVID-19), governments restricted outdoor activities and imposed lockdown quarantine. This change in lifestyle probably affected individuals' eating habits and physical activity.

OBJECTIVE

To examine the effect of lockdown due to the COVID-19 pandemic on maternal antenatal weight gain, neonatal macrosomia, and other maternal and neonatal outcomes of women delivering at an academic medical center in Israel.

METHOD

A retrospective, two-period cohort study conducted at a university teaching medical center in Afula, Israel. The study period was between April and September 2020. This period signifies worsening in pandemic situations, during which citizens experienced strict prolonged lockdown measures. The parallel unexposed period (control period) was between April and September 2019. Singleton pregnancies delivered at >24 weeks were eligible. Primary outcome was incidence of macrosomia. Secondary outcomes included gestational weight gain, body mass index (BMI) at delivery, rates of gestational diabetes mellitus (GDM), mode of delivery, postpartum hemorrhage (PPH), and neonatal outcomes reflecting neonatal birth weight and condition at delivery.

RESULTS

A total of 4,765 women were included, 2,442 in the study group and 2,323 in the control group. The incidence of macrosomia was significantly higher in 2020 (6.2%) than in 2019 (4.9%), (p = .048; OR: 1.29; 95% CI: 1.002- 1.65). Women gained significantly more weight (median 1 kg more), weighed more at delivery (median 1 kg), and had higher BMI at delivery in 2020 compared with those in 2019 (p < .01). The incidence of GDM was 9.5% and 8.5% in the study and control groups respectively (p = .26; OR: 1.12; 95% CI: 0.92-1.37). Greater percentage of women did not perform the glucose challenge test in 2020 (9.9%) compared with those in 2019 (7.5%) (p = .003, OR: 1.36; 95% CI: 1.11-1.67). The incidence of any hypertension related to pregnancy was significantly higher in 2020 compared to 2019 (5.8% vs 4.4% respectively, (p = .042; OR: 1.32; 95% CI: 1.02-1.71). The proportion of women who smoked during pregnancy was also significantly higher in 2020 than in 2019 (5.1% vs 3.7%, respectively, p = .02; OR: 1.40; 95% CI: 1.06-1.86). Delivery mode did not differ, while the incidence of PPH was significantly higher in 2020 than in 2019 (5.6% vs 3.4%, respectively, p = .001; OR: 1.65; 95% CI: 1.25-2.19). Neonatal condition at delivery was comparable.

CONCLUSION

COVID-19-related lockdown was associated with the increased rate of macrosomic infants. This indirect effect of the pandemic is probably related to poorer maternal antenatal metabolic health status. Long-term consequences should be further examined.

Applying WHO2013 diagnostic criteria for gestational diabetes mellitus reveals currently untreated women at increased risk

AIMS

To estimate the prevalence of gestational diabetes mellitus (GDM) in a Danish cohort comparing the current Danish versus the WHO2013 diagnostic criteria, and to evaluate adverse pregnancy outcomes among currently untreated women in the gap between the diagnostic thresholds.

METHODS

Diagnostic testing was performed by a 75 g oral glucose tolerance test (OGTT) at 24-28 weeks' gestation in a cohort of pregnant women. GDM diagnosis was based on the current Danish criterion (2-h glucose ≥ 9.0 mmol/L, GDMDK) and on the WHO2013 criteria (fasting ≥ 5.1, 1 h ≥ 10.0 or 2 h glucose ≥ 8.5 mmol/L, GDMWHO2013). Currently untreated women fulfilling the WHO2013 but not the Danish diagnostic criteria were defined as New-GDM-women (GDMWHO2013-positive and GDMDK-negative). Adverse outcomes risks were calculated using logistic regression.

RESULTS

OGTT was completed by 465 women at a median of 25.7 weeks' gestation. GDMDK prevalence was 2.2% (N = 10) and GDMWHO2013 21.5% (N = 100). New-GDM was present in 19.4% (N = 90), of whom 90.0% had elevated fasting glucose. Pregnancies complicated by New-GDM had higher frequencies of pregnancy-induced hypertension (13.3% vs 4.1%, p = 0.002), large-for-gestational-age infants (22.2% vs 9.9%, p = 0.004), neonatal hypoglycaemia (8.9% vs 1.9%, p = 0.004) and neonatal intensive care unit admission (16.7% vs 5.8%, p = 0.002) compared to pregnancies without GDM.

CONCLUSIONS

GDM prevalence increased tenfold when applying WHO2013 criteria in a Danish population, mainly driven by higher fasting glucose levels. Untreated GDM in the gap between the current Danish and the WHO2013 diagnostic criteria resulted in higher risks of adverse pregnancy outcomes.

Advanced maternal age (AMA) and 75 g oGTT glucose levels are pedictors for insulin therapy in women with gestational diabetes (GDM)

OBJECTIVES

Gestational diabetes (GDM) is a common complication during pregnancy that is strongly associated with adverse fetal and maternal outcomes. Advanced maternal age (≥35 years) is a known risk factor for GDM. Studies advocate that GDM comprises distinctive metabolic entities, suggesting an individualized approach based on early pregnancy characteristics (such as 75 g oGTT values, maternal age, obstetric history).

METHODS

The oGTT blood glucose levels of 1,664 women were categorized into isolated fasting hyperglycemia (GDM-IFH), isolated postprandial hyperglycemia (GDM-IPH) and combined hyperglycemia (GDM-CH), using the levels of the fasting, 1 h and 2 h values after glucose application. These three subtypes were analysed regarding baseline characteristics as well as fetal and maternal outcome in the context of maternal age.

RESULTS

This analysis reveals that the 75 g oGTT levels and maternal age can distinguish metabolic phenotypes in women with GDM. The overall rate of insulin therapy required was higher in women from the GDM-CH group and increased with maternal age (31.7 %, 38.2 %, <35 years, ≥35-39 years respectively, vs. total insulin rate 22.3 %, p-value <0.001). Women ≥35 years displayed a significantly higher caesarean delivery (CD) rate (<35 years 34.6 %, 38.4 %, 41.1 % vs. ≥35 years 54.8 %, 47.6 %, 46.5 %, GDM-IFH, GDM-IPH, GDM-CH respectively, p-value <0.001).

CONCLUSIONS

Women with fasting hyperglycemia, especially those with combined hyperglycemia and advanced maternal age (AMA) display a higher risk for unfavorable perinatal outcome. A categorization based on oGTT values and maternal age, as well as other characteristics can facilitate a basis for clinical risk stratification. Women at risk should receive an individualized and intensified perinatal care as well as interventional therapies.

Commentary from the Italian Association of Medical Diabetologists (AMD) and Italian Society of Diabetology (SID) Interassociative Diabetes and Pregnancy Study Group on the screening and diagnostic methods for gestational diabetes: An open debate

The current board of the interassociative Italian association of medical diabetologists (AMD)/Italian society of diabetology (SID) Diabetes and Pregnancy Italian Study Group commented about two recent papers published in the New England Journal of Medicine that investigated the screening and diagnostic methods for gestational diabetes mellitus (GDM). It is well recognized that effective screening and accurate, early diagnosis of GDM contributes to better management of these women in order to reduce adverse maternal and fetal/neonatal outcomes. However, there is worldwide controversy concerning which screening (selective or universal; one step or two steps) and which diagnostic criteria (glucose thresholds) are appropriate. The main findings of these papers are discussed along with their implications for the management of pregnant women.

Continuous glucose monitoring in individuals undergoing gestational diabetes screening

BACKGROUND

Among guidelines on gestational diabetes mellitus, there is an incongruity about the threshold of maternal hyperglycemia to diagnose gestational diabetes mellitus.

OBJECTIVE

This study aimed to ascertain the association between continuous glucose monitoring metrics and adverse outcomes among individuals undergoing gestational diabetes mellitus screening.

STUDY DESIGN

This was a prospective study (from June 2020 to January 2022) of individuals who underwent 2-step gestational diabetes mellitus screening at ≤30 weeks of gestation. The participants wore a blinded continuous glucose monitoring device (Dexcom G6 Pro; Dexcom, Inc, San Diego, CA) for 10 days starting when they took the 50-g glucose challenge test. The primary outcome was a composite of adverse neonatal outcomes (large for gestational age, shoulder dystocia or neonatal injury, respiratory distress, need for intravenous glucose treatment for hypoglycemia, or fetal or neonatal death). The secondary neonatal outcomes included preterm birth, neonatal intensive care unit admission, hypoglycemia, mechanical ventilation or continuous positive airway pressure, hyperbilirubinemia, and hospital length of stay. The secondary maternal outcomes included weight gain during pregnancy, hypertensive disorders of pregnancy, induction of labor, cesarean delivery, and postpartum complications. Time within the target range (63-140 mg/dL), time above the target range (>140 mg/dL) expressed as a percentage of all continuous glucose monitoring readings, and mean glucose level were analyzed. The Youden index was used to choose the threshold of ≥10% for the time above the target range and association with adverse outcomes.

RESULTS

Of 136 participants recruited, data were available from 92 individuals (67.6%). The 2-step method diagnosed gestational diabetes mellitus in 2 individuals (2.2%). Continuous glucose monitoring indicated that 17 individuals (18.5%) had time above the target range of ≥10%. Individuals with time above the target range of ≥10% had a significantly higher likelihood of composite adverse neonatal outcomes than individuals with time above the target range of <10% (63% vs 18%; P=.001). Furthermore, compared with neonates born to individuals with time above the target range of <10%, neonates born to individuals with time above the target range of ≥10% had an increased likelihood for hypoglycemia (14.5% vs 47%; P=.009) and had a longer length of stay (2 vs 4 days; P=.03). No difference in maternal outcomes was noted between the groups.

CONCLUSION

In this prospective study of individuals undergoing gestational diabetes mellitus screening, a cutoff of the time above the target range of ≥10% using continuous glucose monitoring was associated with a higher rate of neonatal adverse outcomes. A randomized trial of continuous glucose monitoring vs 2-step screening for gestational diabetes mellitus to lower the rate of adverse outcomes is underway (identification number: NCT05430204).

Metabolic and feeding adjustments during pregnancy

Eating behaviours are determined by the integration of interoceptive and environmental inputs. During pregnancy, numerous physiological adaptations take place in the maternal organism to provide an adequate environment for embryonic growth. Among them, whole-body physiological remodelling directly influences eating patterns, commonly causing notable taste perception alterations, food aversions and cravings. Recurrent food cravings for and compulsive eating of highly palatable food can contribute to the development and maintenance of gestational overweight and obesity with potential adverse health consequences for the offspring. Although much is known about how maternal eating habits influence offspring health, the mechanisms that underlie changes in taste perception and food preference during pregnancy (which guide and promote feeding) are only just starting to be elucidated. Given the limited and diffuse understanding of the neurobiology of gestational eating patterns, the aim of this Review is to compile, integrate and discuss the research conducted on this topic in both experimental models and humans. This article sheds light on the mechanisms that drive changes in female feeding behaviours during distinct physiological states. Understanding these processes is crucial to improve gestational parent health and decrease the burden of metabolic and food-related diseases in future generations.

Gestational Glucose Intolerance and Birth Weight-Related Complications

OBJECTIVE

To evaluate the risks of large-for-gestational-age birth weight (LGA) and birth weight-related complications in pregnant individuals with gestational glucose intolerance, an abnormal screening glucose loading test result without meeting gestational diabetes mellitus (GDM) criteria.

METHODS

In a retrospective cohort study of 46,989 individuals with singleton pregnancies who delivered after 28 weeks of gestation, those with glucose loading test results less than 140 mg/dL were classified as having normal glucose tolerance. Those with glucose loading test results of 140 mg/dL or higher and fewer than two abnormal values on a 3-hour 100-g oral glucose tolerance test (OGTT) were classified as having gestational glucose intolerance. Those with two or more abnormal OGTT values were classified as having GDM. We hypothesized that gestational glucose intolerance would be associated with higher odds of LGA (birth weight greater than the 90th percentile for gestational age and sex). We used generalized estimating equations to examine the odds of LGA in pregnant individuals with gestational glucose intolerance compared with those with normal glucose tolerance, after adjustment for age, body mass index, parity, health insurance, race and ethnicity, and marital status. In addition, we investigated differences in birth weight-related adverse pregnancy outcomes.

RESULTS

Large for gestational age was present in 7.8% of 39,685 pregnant individuals with normal glucose tolerance, 9.5% of 4,155 pregnant individuals with gestational glucose intolerance and normal OGTT, 14.5% of 1,438 pregnant individuals with gestational glucose intolerance and one abnormal OGTT value, and 16.0% of 1,711 pregnant individuals with GDM. The adjusted odds of LGA were higher in pregnant individuals with gestational glucose intolerance than in those with normal glucose tolerance overall (adjusted odds ratio [aOR] 1.35, 95% CI 1.23-1.49, P <.001). When compared separately with pregnant individuals with normal glucose tolerance, those with either gestational glucose intolerance subtype had higher adjusted LGA odds (gestational glucose intolerance with normal OGTT aOR 1.21, 95% CI 1.08-1.35, P <.001; gestational glucose intolerance with one abnormal OGTT value aOR 1.77, 95% CI 1.52-2.08, P <.001). The odds of birth weight-related adverse outcomes (including cesarean delivery, severe perineal lacerations, and shoulder dystocia or clavicular fracture) were higher in pregnant individuals with gestational glucose intolerance with one abnormal OGTT value than in those with normal glucose tolerance.

CONCLUSION

Gestational glucose intolerance in pregnancy is associated with birth weight-related adverse pregnancy outcomes. Glucose lowering should be investigated as a strategy for lowering the risk of these outcomes in this group.

Pregnancy outcomes of women with untreated 'mild' gestational diabetes (gestational diabetes by the WHO 2013 but not by the WHO-1999 diagnostic criteria) - A population-based cohort study

AIMS

We compared pregnancy outcomes of untreated 'mild' GDM (GDM by WHO 2013 but not by WHO-1999) to normal glucose tolerant women (NGT).

METHODS

In a universal screening program 4333 pregnant women had a 3-point 75 g OGTT in Hungary in 2009-2013. By WHO-2013 untreated NGT was diagnosed in n = 3303, 'mild' GDM in n = 336 cases.

RESULTS

'Mild' GDM women were older (mean difference, SE: 1.4, 0.3 yrs), had higher fasting (1.0, 0.02), 60-minute (1.0, 0.09), and 120-minute (0.4, 0.06 mmol/l) blood glucose, and blood pressure (2.6, 0.5/2.0, 0.5 mmHg). Weight gain was similar in both groups (-0.3, 0.3 kg). GDM newborns were heavier (142, 50 g) and were more frequently macrosomic (>4000 g, OR 1.85, 95 %CI 1.35-2.54). Hypertension during pregnancy was more prevalent in the GDM group (OR 1.55, 95 %CI 1.05-2.28), as well as induced (OR 1.38, 95 %CI 1.10-1.74) and instrumental delivery (OR 1.34, 95 %CI 1.07-1.68), and acute caesarean section (OR 1.32, 95 %CI 1.04-1.64). Most of these differences substantially attenuated or became non-significant after adjustment for pre-pregnancy BMI.

CONCLUSIONS

Pregnancy outcomes of 'mild' GDM were worse compared to normal glucose tolerant women however these differences were explained by the pre-pregnancy BMI difference between groups.

Hyperglycemia and Hyperlipidemia with Kidney or Liver Transplantation: A Review

Although solid organ transplantation in persons with diabetes mellitus is often associated with hyperglycemia, the risk of hyperlipidemia in all organ transplant recipients is often underestimated. The diagnosis of diabetes often predates transplantation; however, in a moderate percentage of allograft recipients, perioperative hyperglycemia occurs triggered by antirejection regimens. Post-transplant prescription of glucocorticoids, calcineurin inhibitors and mTOR inhibitors are associated with increased lipid concentrations. The existence of diabetes mellitus prior to or following a liver transplant is associated with shorter times of useful allograft function. A cycle involving Smad, TGF beta, m-TOR and toll-like receptors has been identified in the contribution of rejection and aging of allografts. Glucocorticoids (prednisone) and calcineurin inhibitors (cyclosporine and tacrolimus) induce hyperglycemia associated with insulin resistance. Azathioprine, mycophenolate and prednisone are associated with lipogenesis. mTOR inhibitors (rapamycin) are used to decrease doses of atherogenic agents used for immunosuppression. Post-transplant medication management must balance immune suppression and glucose and lipid control. Concerns regarding rejection often override those relative to systemic and organ vascular aging and survival. This review focuses attention on the underlying mechanism of relationships between glycemia/lipidemia control, transplant rejection and graft aging.

Dose-Response Relationship between Gestational Weight Gain and Neonatal Birthweight in Chinese Women with Excess Weight/Obesity and Gestational Diabetes Mellitus

Total gestational weight gain (GWG) is identified as a strong and potentially controllable predictor of long-term health outcomes in women with gestational diabetes mellitus (GDM) and infants. When the total GWG of women with excess weight/obesity and GDM does not exceed the Institute of Medicine (IOM) suggested range, neonatal birthweight outcomes may be favorable, but the evidence is limited. Therefore, the objective of this study was to evaluate the dose-response relationship between increased total GWG and the risk of neonatal birthweight in Chinese women with excess weight/obesity and GDM. This study obtained electronic medical records (EMR) from the hospital information system (HIS) of the Chongqing Health Center for Women and Children between July 2017, and June 2020. A retrospective study analyzed the effect of the total GWG of women with excess weight/obesity and GDM on neonatal birthweight. The dose-response relationship between total GWG and neonatal birthweight was studied using a generalized linear model and embedded restricted cubic splines (RCS). The average age of all women with GDM was 31.99 ± 4.47 years, and 27.61% were advanced maternal age (≥35 years). The total GWG among women with excess weight and obesity and GDM greater than the IOM recommendations were found in 42.96% and 58.62% of cases, respectively. Total GWG in women with excess weight and excessing the IOM recommended range is a risk factor for large gestational age (LGA) [adjusted odds ratio (aOR) 0.1.47, 1.08-2.01] and macrosomia (aOR 1.55, 1.04-2.31). In the obesity above group, excessive weight gain increased the risk of LGA (aOR 2.92, 1.33-6.41) and macrosomia (aOR 2.83, 1.03-7.72). We used an RCS to examine pregnant women with excess weight and GDM and discovered a linear dose-response relationship between total GWG and LGA/macrosomia. In women with excess weight and obesity, increases in total GWG above the lowest end of the IOM recommendations range (7 kg and 5 kg) were associated with an increased risk of LGA and macrosomia. Therefore, research is urgently needed to support maternal and newborn health to provide recommendations for the ideal weight increase in women with excess weight/obesity and GDM.

Long-term cost-effectiveness of implementing a lifestyle intervention during pregnancy to reduce the incidence of gestational diabetes and type 2 diabetes

AIMS/HYPOTHESIS

The aim of this study was to determine the long-term cost-effectiveness and return on investment of implementing a structured lifestyle intervention to reduce excessive gestational weight gain and associated incidence of gestational diabetes mellitus (GDM) and type 2 diabetes mellitus.

METHODS

A decision-analytic Markov model was used to compare the health and cost-effectiveness outcomes for (1) a structured lifestyle intervention during pregnancy to prevent GDM and subsequent type 2 diabetes; and (2) current usual antenatal care. Life table modelling was used to capture type 2 diabetes morbidity, mortality and quality-adjusted life years over a lifetime horizon for all women giving birth in Australia. Costs incorporated both healthcare and societal perspectives. The intervention effect was derived from published meta-analyses. Deterministic and probabilistic sensitivity analyses were used to capture the impact of uncertainty in the model.

RESULTS

The model projected a 10% reduction in the number of women subsequently diagnosed with type 2 diabetes through implementation of the lifestyle intervention compared with current usual care. The total net incremental cost of intervention was approximately AU$70 million, and the cost savings from the reduction in costs of antenatal care for GDM, birth complications and type 2 diabetes management were approximately AU$85 million. The intervention was dominant (cost-saving) compared with usual care from a healthcare perspective, and returned AU$1.22 (95% CI 0.53, 2.13) per dollar invested. The results were robust to sensitivity analysis, and remained cost-saving or highly cost-effective in each of the scenarios explored.

CONCLUSIONS/INTERPRETATION

This study demonstrates significant cost savings from implementation of a structured lifestyle intervention during pregnancy, due to a reduction in adverse health outcomes for women during both the perinatal period and over their lifetime.

Treatment of women with mild gestational diabetes mellitus decreases the risk of adverse perinatal outcomes

AIMS

Glycemic thresholds used to diagnose gestational diabetes mellitus (GDM) are a continued subject of debate. Lower glycemic thresholds identify women with milder GDM for whom treatment benefit is unclear. We compared adverse maternal and neonatal outcomes in treated and untreated women with mild hyperglycemia.

METHODS

We reviewed 11 553 patient charts from two tertiary care centers and included singleton pregnancies >32-week gestation. GDM was diagnosed using the one- or two-step 75 g oral glucose tolerance test (OGTT) depending on the center. All OGTT results were reviewed. Women with glycemic values falling between the thresholds of the two tests, referred to as intermediate hyperglycemic (IH), defined as FPG 5.1-5.2 mmol/L, 1 h PG 10.0-10.5 mmol/L, or 2 h PG 8.5-8.9 mmol/L at 75 g OGTT, were untreated at center A and treated at center B.

RESULTS

There were 630 women with IH, 334 were untreated (center A) and 296 who were treated (center B). After adjusting for covariates, untreated IH women had significantly higher rates of gestational hypertension (aOR 6.02, P = 0.002), large for gestational age (LGA) (aOR 3.73, P < 0.001) and birthweights > 4000 g (aOR 3.35, P = 0.001). Our results indicate that treating 11 women with IH would prevent one LGA birth and treating 13 would prevent 1 birthweight > 4000 g.

CONCLUSION

The diagnosis of GDM using the two-step OGTT fails to identify subgroups of women with mild hyperglycemia that would benefit from treatment to lower the risk for adverse maternal and neonatal outcomes. Treatment of women with mild hyperglycemia decreased the risk of LGA and birthweight >4000 g by 3-fold.

Non-efficacy of early intervention strategy for non-obese patients with early-onset gestational diabetes mellitus: solely based on the short-term outcomes

INTRODUCTION

To verify the effectiveness of intervention in early pregnancy for women with early-onset gestational diabetes mellitus (GDM).

RESEARCH DESIGN AND METHODS

This study included women with a singleton pregnancy who were diagnosed with early-onset GDM by 20 weeks of gestation according to the International Association of Diabetes and Pregnancy Study Group (IADPSG) threshold. We retrospectively evaluated the pregnancy outcomes in pregnant women with early-onset GDM. In the treatment from early pregnancy group (n=286), patients were diagnosed with early-onset GDM at the Yokohama City University Medical Center (YCU-MC) in 2015-2017 and were treated for GDM from early pregnancy. Concerning the treatment from mid-pregnancy group (n=248), participants were diagnosed with early-onset GDM at five sites, including the YCU-MC in 2018-2019, and were followed up without treatment until the second 75 g oral glucose tolerance test (OGTT) at 24-28 weeks of gestation. Treatment for GDM was given only if the GDM pattern was still present in the second OGTT.

RESULTS

There were no significant differences in maternal backgrounds, including GDM risk factors and gestational weight gain, between the groups. Among the treatment from mid-pregnancy group, the false-positive early GDM was 124/248 (50%). Regarding pregnancy outcome, the rate of large for gestational age (LGA) was 8.8% in the treatment from early pregnancy group and 10% in the treatment from mid-pregnancy group, with no significant difference, whereas small for gestational age (SGA) was significantly higher in the treatment from early pregnancy group (9.4%) than in the treatment from mid-pregnancy group (4.8%) (p=0.046). There were no significant differences in maternal adverse events and neonatal outcomes between the groups. In a subanalysis limited to body mass index >25 kg/m², LGA was significantly lower in the treatment from early pregnancy group than in the treatment from mid-pregnancy group.

CONCLUSIONS

The strategy for diagnosing GDM by IADPSG thresholds in early pregnancy and providing treatment to all patients from early pregnancy did not improve the pregnancy outcomes, but rather increased the SGA rate.

The impact of inter-laboratory glucose bias on the diagnosis of gestational diabetes mellitus: Comparison of common automated central laboratory methods

BACKGROUND AND AIMS

The diagnosis of gestational diabetes mellitus (GDM) is based exclusively on glucose measurements, which are highly influenced by pre-analytical and analytical factors. Therefore, poor agreement across laboratories may affect the prevalence of GDM. We aimed to determine the inter-laboratory bias of glucose measurements and the impact on GDM prevalence.

MATERIAL AND METHODS

A prospective cohort study of women (n=110) referred for second-trimester GDM diagnostics using a 75 g oral glucose tolerance test. Maternal glucose was assessed from venous plasma at fasting, 1 h and 2 h. Venous blood were collected in Fluoride Citrate tubes and frozen. Samples were analyzed at five central laboratories using four different automated glucose Hexokinase methods and GDM prevalence was evaluated according to WHO2013 diagnostic criteria.

RESULTS

Maximum inter-laboratory bias was 0.19, 0.30 and 0.27 mmol/L in fasting, 1 h and 2 h samples, respectively. GDM prevalence ranged 30.0-41.1% across laboratories.

CONCLUSION

Inter-laboratory bias for mean venous glucose was low and within desirable limits. Nonetheless, the impact on GDM prevalence was considerable, which may inappropriately affect clinical practice.

Benefits and harms associated with an increase in gestational diabetes diagnosis in Queensland, Australia: a retrospective cohort comparison of diagnosis rates, outcomes, interventions and medication use for two periods, 2011-2013 and 2016-2018, using a large perinatal database

OBJECTIVES

To assess benefits and harms arising from increasing gestational diabetes (GDM) diagnosis, including for women with normal-sized babies.

DESIGN, SETTING AND PARTICIPANTS

Diagnosis rates, outcomes, interventions and medication use are compared in a retrospective cohort study of 229 757 women birthing in public hospitals of the Australian State of Queensland during two periods, 2011-2013 and 2016-2018, using data from the Queensland Perinatal Data Collection.

OUTCOME MEASURES

Comparisons include hypertensive disorders, caesarean section, shoulder dystocia and associated harm, induction of labour (IOL), planned birth (PB), early planned birth <39 weeks (EPB), spontaneous labour onset with vaginal birth (SLVB) and medication use.

RESULTS

GDM diagnosis increased from 7.8% to 14.3%. There was no improvement in shoulder dystocia associated injuries, hypertensive disorders or caesarean sections. There was an increase in IOL (21.8%-30.0%; p<0.001), PB (36.3% to 46.0%; p<0.001) and EPB (13.5%-20.6%; p<0.001), and a decrease in SLVB (56.0%-47.3%; p<0.001). Women with GDM experienced an increase in IOL (40.9%-49.8%; p<0.001), PB (62.9% to 71.8%; p<0.001) and EPB (35.3%-45.7%; p<0.001), and a decrease in SLVB (30.01%-23.6%; p<0.001), with similar changes for mothers with normal-sized babies. Of women prescribed insulin in 2016-2018, 60.4% experienced IOL, 88.5% PB, 76.4% EPB and 8.0% SLVB. Medication use increased from 41.2% to 49.4% in women with GDM, from 3.2% to 7.1% in the antenatal population overall, from 3.3% to 7.5% in women with normal-sized babies and from 2.21% to 4.38% with babies less than the 10th percentile.

CONCLUSION

Outcomes were not apparently improved with increased GDM diagnosis. The merits of increased IOL or decreased SLVB depend on the views of individual women, but categorising more pregnancies as abnormal, and exposing more babies to the potential effects of early birth, medication effects and growth limitation may be harmful.

Bridging the Gap: Pregnancy-And Lactation-Associated Osteoporosis

Early diagnosis of pregnancy- and lactation-associated osteoporosis (PLO) is mandatory for a good outcome. Standard care is not a matter of conventional guidelines, rather it requires an individualized strategy while true overall incidence and pathogeny remain open issues. This is a narrative review based on full-length English articles, published between January 2021 and March 2023 and accessed via PubMed (no traumatic fractures or secondary osteoporosis are included). Our case-sample-based analysis included 836 females with PLO (the largest cohort based on published cases so far) through 12 studies and 24 single case reports. Except for one survey, these involved retrospective cohorts of small size (6-10 females/study) to medium size (23-47 women/study), and large cohorts with >50 subjects per study (a maximum of 379). Age of diagnosis: from 24 to 40 years for case reports (most subjects being over 30 and primigravida), while original studies indicated an average age between 31 and 34.18 years. Type of fractures underlined a most frequent vertebral phenotype (a mean of 2 to 5.8 vertebral fractures per patient) versus a most severe non-vertebral phenotype (hip and femoral neck fractures mostly requiring surgery). Potential contributors varied: smoking (1/3-1/2 of subjects), family history of osteoporosis (1/3), heparin and glucocorticoid use in pregnancy, low body mass index (majority of cases), hypovitaminosis D; and (with a low level of statistical significance) anti-psychotic medication, gestational diabetes, lupus, thrombophilia, anemia, in vitro fertilization (1/3 in one study), twin pregnancy, tocolysis with MgSO4, and postpartum thyroiditis. Most remarkably, up to 50% of PLO patients harbor mutations of LRP5, WNT1, and COL1A1/A2 (more damaged form with potential benefits from osteoanabolic drugs); gene testing might become the new norm in PLO. The low index of clinical suspicion should be supported by performing magnetic resonance imaging (gold standard in pregnancy) with DXA (in lactation). Low bone mineral density is expected (Z-score varying from -2.2 SD to -4 SD, unless normal which does not exclude PLO). Bone turnover markers might be useful in individuals with normal DXA, in pregnancy when DXA cannot be performed, and in following the response to anti-osteoporosis drugs. Alternatively, microarchitecture damage might be reflected by DXA-trabecular bone score and high-resolution peripheral quantitative computed tomography. Specific medical interventions are currently focused on teriparatide (TPT) use (3 studies; n = 99 females treated with TPT and an additional subgroup of 18 patients from the gene-analysis-based study, thus a total of 117 females) which seems to be the therapy of choice as reflected by these new data: 6-24 months, 20 µg/day, no sequential therapy needed; case selection based on high fracture risk is necessary). The first case using romosozumab was reported in 2022. PAO/LAO remains a challenging condition which is a battle for the wellbeing of two individuals, on one hand, considering maternal-fetal outcomes and taking care of the offspring, but it is a battle for a multidisciplinary team, on the other hand, since a standardized approach is lacking.

Combining HbA1c and insulin resistance to assess the risk of gestational diabetes mellitus: a prospective cohort study

OBJECTIVE

To investigate the association of glycated hemoglobin (HbA1c) and homeostasis model assessment insulin resistance (HOMA-IR) with gestational diabetes mellitus (GDM) risk.

METHODS

Data for this study were from a prospective cohort in Hangzhou, China. We included pregnant women with HbA1c, fasting insulin, and fasting glucose (FG) measured at 15-20 weeks of gestation and underwent oral glucose tolerance test (OGTT) at 24-28 weeks. Based on HbA1c and HOMA-IR, participants were divided into four groups. We estimated the odds ratios (OR) with 95% confidence intervals (CI) to assess the associations of HbA1c and HOMA-IR with GDM occurrence. Finally, we the potential additive interaction between HbA1c and HOMA-IR by calculating relative excess risk due to interaction (RERI) and the attributable proportion due to interaction (AP).

RESULT

462 pregnant women were included, of whom 136 (29.44%) developed GDM. Based on HbA1c and HOMA-IR, the study population was divided into four groups, with the percentages of each group being 51.30%, 15.58%, 20.56%, and 12.55%, respectively. The incidence of GDM increased with the increase of HOMA-IR and HbA1c, respectively, and the risk of GDM was significantly increased when both HOMA-IR and HbA1c were elevated. However, no such risk was observed in pregnant women < 35 years. Finally, we found significantly higher FG at 24-28 weeks in the high HOMA-IR and HbA1c group among GDM-positive pregnant women.

CONCLUSIONS

The incidence of GDM increased with increasing HbA1c and HOMA-IR, and the risk of GDM was significantly increased when both HbA1c and HOMA-IR were elevated. This finding may help to identify high-risk women for GDM early in pregnancy and provide timely interventions.

Exploring patients' perspectives of gestational diabetes mellitus screening and counselling in Ontario: A grounded theory study

INTRODUCTION

Gestational diabetes mellitus (GDM) is associated with adverse perinatal outcomes. Approaches to screening for GDM continue to evolve, introducing potential variability of care. This study explored the impact of these variations on GDM counselling and screening from the perspectives of pregnant individuals.

METHODS

Following a Corbin and Strauss approach to qualitative, grounded theory we recruited 28 individuals from three cities in Ontario, Canada who had a singleton pregnancy under the care of either a midwife, family physician or obstetrician. Convenience and purposive sampling techniques were used. Semi-structured telephone interviews were conducted and transcribed verbatim between March and December 2020. Transcripts were analysed inductively resulting in codes, categories and themes.

RESULTS

Three themes were derived from the data about GDM screening and counselling: 'informing oneself', 'deciding' and 'screening'. All participants, regardless of geographical region, or antenatal care provider, moved through these three steps during the GDM counselling and screening process. Differences in counselling approaches between pregnancy care providers were noted throughout the 'informing' and 'deciding' stages of care. Factors influencing these differences included communication, healthcare autonomy and patient motivation to engage with health services. No differences were noted within care provider groups across the three geographic regions. Participant experiences of GDM screening were influenced by logistical challenges and personal preferences towards testing.

CONCLUSION

Informing oneself about GDM may be a crucial step for facilitating decision-making and screening uptake, with an emphasis on information provision to facilitate patient autonomy and motivation.

PATIENT OR PUBLIC CONTRIBUTION

Participants of our study included patients and service users. Participants were actively involved in the study design due to the qualitative, patient-centred nature of the research methods employed. Analysis of results was structured according to the emergent themes of the data which were grounded in patient perspectives and experiences.

Comparison of diagnostic accuracy for diabetes diagnosis: A systematic review and network meta-analysis

Aim

Fasting Plasma Glucose (FPG) and Hemoglobin A1c (HbA1c) are used as diagnostic tests for diagnosing diabetes mellitus, but it is unclear which test has the best diagnostic accuracy. This systematic review and network meta-analysis aimed to estimate the diagnostic accuracy of HbA1c ≥ 6.5%, FPG ≥ 126 mg/dl, and the combination of HbA1c ≥ 6.5% or FPG ≥ 126 mg/dl (HbA1c| FPG), compared with Oral Glucose Tolerance Test (OGTT) ≥ 200 mg/dl for diagnosis diabetes.

Materials and methods

We performed a comprehensive search in PubMed, Embase, Cochrane Library, and Scopus from inception to September 24th, 2021. Inclusion criteria were any study design comparing HbA1c ≥ 6.5%, FPG ≥ 126 mg/dl, and HbA1c ≥ 6.5% or FPG ≥ 126 mg/dl with OGTT ≥ 200 mg/dl as the reference test. Data were independently extracted, risk of bias was assessed using QUADAS-2 by two reviewers. Network meta-analysis was done using a bivariate regression model using the Bayesian framework. The relative ranking of all tests was also assessed.

Results

Out of 5,026 studies, 73 were included. The sensitivities of HbA1c, FPG, and HbA1c| FPG were 0.51 [95% Credible Interval (CrI): 0.43, 0.58], 0.49 (95% CrI: 0.43, 0.55), and 0.64 (95% CrI: 0.51, 0.75), while the specificities were 0.96 (95% CrI: 0.94, 0.97), 0.98 (95% CrI: 0.97, 0.98), and 0.95 (95% CrI: 0.88, 0.98), respectively. The corresponding positive likelihood ratios (LR) were 13.36 (95% CrI: 8.91, 20.72), 21.94 (95% CrI: 15.04, 31.88), and 11.78 (95% CrI: 5.48, 26.56). HbA1c| FPG is superior based on sensitivity, whereas FPG is ranked best based on specificity and positive LR.

Conclusion

Our findings suggest that FPG ≥ 126 mg/dl should be recommended as the best diagnostic test for diabetes.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42021282856.

Utility of In Vivo Magnetic Resonance Imaging Is Predictive of Gestational Diabetes Mellitus During Early Pregnancy

CONTEXT

Gestational diabetes (GDM) imposes long-term adverse health effects on the mother and fetus. The role of magnetic resonance imaging (MRI) during early gestation in GDM has not been well-studied.

OBJECTIVE

To investigate the role of quantitative MRI measurements of placental volume and perfusion, with distribution of maternal adiposity, during early gestation in GDM.

METHODS

At UCLA outpatient antenatal obstetrics clinics, ∼200 pregnant women recruited in the first trimester were followed temporally through pregnancy until parturition. Two placental MRI scans were prospectively performed at 14 to 16 weeks and 19 to 24 weeks gestational age (GA). Placental volume and blood flow (PBF) were calculated from placental regions of interest; maternal adiposity distribution was assessed by subcutaneous fat area ratio (SFAR) and visceral fat area ratio (VFAR). Statistical comparisons were performed using the two-tailed t test. Predictive logistic regression modeling was evaluated by area under the curve (AUC).

RESULTS

Of a total 186 subjects, 21 subjects (11.3%) developed GDM. VFAR was higher in GDM vs the control group, at both time points (P < 0.001 each). Placental volume was greater in GDM vs the control group at 19 to 24 weeks GA (P = 0.01). Combining VFAR, placental volume and perfusion, improved the AUC to 0.83 at 14 to 16 weeks (positive predictive value [PPV] = 0.77, negative predictive value [NPV] = 0.83), and 0.81 at 19 to 24 weeks GA (PPV = 0.73, NPV = 0.86).

CONCLUSION

A combination of MRI-based placental volume, perfusion, and visceral adiposity during early pregnancy demonstrates significant changes in GDM and provides a proof of concept for predicting the subsequent development of GDM.

[Gestational diabetes mellitus (Update 2023)]

Gestational diabetes (GDM) is defined as any degree of glucose intolerance with onset during pregnancy and is associated with increased feto-maternal morbidity as well as long-term complications in mothers and the offspring. Women detected to have diabetes early in pregnancy receive the diagnosis of overt, non-gestational, diabetes (glucose: fasting ≥ 126 mg/dl, spontaneous ≥ 200 mg/dl or HbA_1c ≥ 6.5% before 20 weeks of gestation). GDM is diagnosed by an oral glucose tolerance test (oGTT) or increased fasting glucose (≥ 92 mg/dl). Screening for undiagnosed type 2 diabetes at the first prenatal visit is recommended in women at increased risk (history of GDM/pre-diabetes; malformation, stillbirth, successive abortions or birth weight > 4500 g previously; obesity, metabolic syndrome, age > 35 years, vascular disease; clinical symptoms of diabetes (e.g. glucosuria) or ethnic origin with increased risk for GDM/T2DM (Arab, South- and Southeast Asian, Latin American)) using standard diagnostic criteria. Performance of the oGTT (120 min; 75 g glucose) may already be indicated in the first trimester in high-risk women but is mandatory between gestational week 24-28 in all pregnant women with previous non-pathological glucose metabolism. Following WHO recommendations, which are based on the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study, GDM is defined, if fasting venous plasma glucose is ≥ 92 mg/dl or 1 h ≥ 180 mg/dl or 2 h ≥ 153 mg/dl after glucose loading (international consensus criteria). In case of one pathological value a strict metabolic control is mandatory. After bariatric surgery we do not recommend to perform an oGTT due to risk of postprandial hypoglycemia. All women with GDM should receive nutritional counseling, be instructed in blood glucose self-monitoring and motivated to increase physical activity to moderate intensity levels-if not contraindicated (Evidence level A). If blood glucose levels cannot be maintained in the therapeutic range (fasting < 95 mg/dl and 1 h after meals < 140 mg/dl, Evidence level B) insulin therapy should be initiated as first choice (Evidence level A). Maternal and fetal monitoring is required in order to minimize maternal and fetal/neonatal morbidity and perinatal mortality. Regular obstetric examinations including ultrasound examinations are recommended (Evidence level A). Neonatal care of GDM offspring at high risk for hypoglycaemia includes blood glucose measurements after birth and if necessary appropriate intervention. Monitoring the development of the children and recommendation of healthy lifestyle are important issues to be tackled for the whole family. After delivery all women with GDM have to be reevaluated as to their glucose tolerance by a 75 g oGTT (WHO criteria) 4-12 weeks postpartum. Assessment of glucose parameters (fasting glucose, random glucose, HbA_1c or optimally oGTT) are recommended every 2-3 years in case of normal glucose tolerance. All women have to be instructed about their increased risk of type 2 diabetes and cardiovascular disease at follow-up. Possible preventive meassures, in particular lifestyle changes as weight management and maintenance/increase of physical activity should be discussed (evidence level A).

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

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

The Effect of Bariatric Surgery upon Diabetes Mellitus: A Proof of Concept by Using the Case of the Mid-Term Effect of Lap Adjustable Gastric Banding (LAGB) on Patients with Diabetes

Obesity is a worldwide epidemic, with numbers on the rise in the world. Obesity is strongly correlated with increased morbidity and mortality. One of the major factors affecting this increase is comorbid diseases such as diabetes mellitus (DM), which is strongly associated with and dependent on the degree of obesity. Thus, it is not surprising that when efficient surgical treatments were found to battle obesity, researchers soon found them to be relevant and effective for battling DM as well. Laparoscopic Adjustable Gastric Banding (LAGB) is a common surgical treatment for morbid obesity. LAGB has the potential to improve control of the comorbidities of morbid obesity, primarily diabetes mellitus (DM). Our hypothesis was that patients treated with LAGB would have a long-term improvement in the control of DM and that due to its unique mechanism of action, this can lend us a better understanding of how to battle diabetes in an efficient and effective way. This was a cohort study based on patients who underwent LAGB surgery in our institution 4 to 7 years previously and had DM type 2 at the time of surgery. Data were collected from patient’s charts and a telephone interview-based questionnaire including demographics, health status, and quality-of-life assessment (Bariatric Analysis and Reporting Outcome System [BAROS]). Seventy patients participated in the current study. The average follow-up time was 5.1 ± 0.9 years post-surgery. The average weight prior to surgery was 122.0 ± 20.2 kg, and on the day of the interview it was 87.0 ± 17.6 kg (p < 0.001). The average body mass index before surgery was 43.8 ± 5.1, and on the day of the interview it was 31.2 ± 4.8 (p < 0.001). On the day of the interview, 47.1% of the participants were cured of DM (not receiving treatment, whether dietary or pharmacologic). The sum of ranks for diabetes was lower after the surgery (p < 0.001), as was HTN and its treatment (p < 0.001). We have shown in this study that LAGB is an effective treatment for morbid obesity, as well as two comorbidities that come with it—DM type 2 and Hypertension (HTN)—in a longer period than previously shown, and with a unique look at the underlying mechanism of action of this procedure. There is a need for further studies to consolidate our findings and characterize which patients are more prone to enjoy these remarkable surgical benefits.

Gestationsdiabetes: Welche Diagnoseschwelle ist die beste?

Die Behandlung eines Schwangerschaftsdiabetes verbessert die Gesundheit von Mutter und Kind, aber die diagnostischen Kriterien für den Gestationsdiabetes variieren weltweit. Ein Team neuseeländischer Forscher*innen untersuchten im Rahmen der „GEMS“-Studie, ob man bei Schwangeren mit Gestationsdiabetes mithilfe etwas höherer Grenzwerte die Folgen einschränken könne, ohne Mutter und Kind dadurch höheren Risiken auszusetzen.

Gestational Diabetes Mellitus—Recent Literature Review

Gestational diabetes mellitus (GDM), which is defined as a state of hyperglycemia that is first recognized during pregnancy, is currently the most common medical complication in pregnancy. GDM affects approximately 15% of pregnancies worldwide, accounting for approximately 18 million births annually. Mothers with GDM are at risk of developing gestational hypertension, pre-eclampsia and termination of pregnancy via Caesarean section. In addition, GDM increases the risk of complications, including cardiovascular disease, obesity and impaired carbohydrate metabolism, leading to the development of type 2 diabetes (T2DM) in both the mother and infant. The increase in the incidence of GDM also leads to a significant economic burden and deserves greater attention and awareness. A deeper understanding of the risk factors and pathogenesis becomes a necessity, with particular emphasis on the influence of SARS-CoV-2 and diagnostics, as well as an effective treatment, which may reduce perinatal and metabolic complications. The primary treatments for GDM are diet and increased exercise. Insulin, glibenclamide and metformin can be used to intensify the treatment. This paper provides an overview of the latest reports on the epidemiology, pathogenesis, diagnosis and treatment of GDM based on the literature.