Implications of the introduction of new criteria for the diagnosis of gestational diabetes: a health outcome and cost of care analysis

Insulin Use During Gestational and Pre-existing Diabetes in Pregnancy: A Systematic Review of Study Design

INTRODUCTION

Insulin is the first-line pharmacologic therapy for women with diabetes in pregnancy. However, conducting well-designed randomized clinical trials (RCTs) and achieving recommended glycemic targets remains a challenge for this unique population. This systematic literature review (SLR) aimed to understand the evidence for insulin use in pregnancy and the outcome metrics most often used to characterize its effect on glycemic, maternal and fetal outcomes in gestational diabetes mellitus (GDM) and in pregnant women with diabetes.

METHODS

An SLR was conducted using electronic databases in Medline, EMBASE via Ovid platform, evidence-based medicine reviews (2010-2020) and conference proceedings (2018-2019). Studies were included if they assessed the effect of insulin treatment on glycemic, maternal or fetal outcomes in women with diabetes in pregnancy. Studies on any type of diabetes other than gestational or pre-existing diabetes as well as non-human studies were excluded.

RESULTS

In women diagnosed with GDM or pre-existing diabetes, most studies compared treatment of insulin with metformin (n = 35) followed by diet along with lifestyle intervention (n = 24) and glibenclamide (n = 12). Most studies reporting on glycemic outcomes compared insulin with metformin (n = 22) and glibenclamide (n = 4). Fasting blood glucose was the most reported clinical outcome of interest. Among the studies reporting maternal outcomes, method of delivery and delivery complications were most commonly reported. Large for gestational age, stillbirth and perinatal mortality were the most common fetal outcomes reported.

CONCLUSION

This SLR included a total of 108 clinical trials and observational studies with diverse populations and treatment arms. Outcomes varied across the studies, and a lack of consistent outcome measures to manage diabetes in pregnant women was observed. This elucidates a need for global consensus on study design and standardized clinical, maternal and fetal outcomes metrics.

A cost-effectiveness evaluation of a dietitian-delivered telephone coaching program during pregnancy for preventing gestational diabetes mellitus

BACKGROUND

This study aimed to evaluate the cost-effectiveness of a telehealth coaching intervention to prevent gestational diabetes mellitus (GDM) and to calculate the breakeven point of preventing GDM.

METHODS

Data to inform the economic evaluation model was sourced directly from the large quaternary hospital in Brisbane, where the Living Well during Pregnancy (LWdP) program was implemented, and further supplemented with literature-based estimates where data had not been directly collected in the trial. A cost-effectiveness model was developed using a decision tree framework to estimate the potential for cost savings and quality of life improvement. A total of 1,315 pregnant women (49% with a BMI 25-29.9, and 51% with a BMI ≥ 30) were included in the analyses.

RESULTS

The costs of providing routine care and routine care plus LWdP coaching intervention to pregnant women were calculated to be AUD 20,933 and AUD 20,828, respectively. The effectiveness of the LWdP coaching program (0.894 utility) was slightly higher compared to routine care (0.893). Therefore, the value of the incremental cost-effectiveness ratio (ICER) was negative, and it indicates that the LWdP coaching program is a dominant strategy to prevent GDM in pregnant women. We also performed a probabilistic sensitivity analysis using Monte Carlo simulation through 1,000 simulations. The ICE scatter plot showed that the LWdP coaching intervention was dominant over routine care in 93.60% of the trials using a willingness to pay threshold of AUD 50,000.

CONCLUSION

Findings support consideration by healthcare policy and decision makers of telehealth and broad-reach delivery of structured lifestyle interventions during pregnancy to lower short-term costs associated with GDM to the health system.

Oral glucose tolerance test and continuous glucose monitoring for gestational diabetes diagnosis: a survey study of women and health care professionals

AIMS

The oral glucose tolerance test (OGTT), used for gestational diabetes mellitus (GDM) diagnosis for over 65 years, has poor acceptability and tolerability. Continuous glucose monitoring is being considered as potential alternative. The aim of our study was to formally assess women's and health care professionals' perception of both tests as diagnostic tools for GDM.

METHODS

Participants in a pilot study on continuous glucose monitoring for GDM diagnosis were invited to fill two questionnaires, each of 6 Likert-scale and one optional open-ended question. A range of healthcare practitioners were also invited to fill a questionnaire of 13 Likert-scale and 7 optional open-ended questions.

RESULTS

Sixty women completed the OGTT and 70 the continuous glucose monitoring questionnaire. OGTT was reported as poorly acceptable. Continuous glucose monitoring was described as significantly more tolerable (81% vs 27% 5/5 general acceptability rate, p < 0.001); ninety-three percent of the participants would recommend it for GDM diagnosis. Thirty health care professionals completed the survey. Most of them (73%) had confidence in OGTT as a diagnostic test for GDM with 66% raising some concerns. Doubts on continuous glucose monitoring were raised in terms of costs, accessibility and accuracy for GDM diagnosis due to "lack of evidence".

CONCLUSIONS

Continuous glucose monitoring was substantially better tolerated for women than OGTT. Current lack of evidence for diagnostic accuracy for GDM underlines the need for studies on correlation between continuous glucose monitoring parameters and pregnancy outcomes to strengthen evidence for its use as diagnostic test for GDM.

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.

Temporal validation and updating of a prediction model for the diagnosis of gestational diabetes mellitus

OBJECTIVE

The original Monash gestational diabetes mellitus (GDM) risk prediction in early pregnancy model is internationally externally validated and clinically implemented. We temporally validate and update this model in a contemporary population with a universal screening context and revised diagnostic criteria and ethnicity categories, thereby improving model performance and generalizability.

STUDY DESIGN AND SETTING

The updating dataset comprised of routinely collected health data for singleton pregnancies delivered in Melbourne, Australia from 2016 to 2018. Model predictors included age, body mass index, ethnicity, diabetes family history, GDM history, and poor obstetric outcome history. Model updating methods were recalibration-in-the-large (Model A), intercept and slope re-estimation (Model B), and coefficient revision using logistic regression (Model C1, original ethnicity categories; Model C2, revised ethnicity categories). Analysis included 10-fold cross-validation, assessment of performance measures (c-statistic, calibration-in-the-large, calibration slope, and expected-observed ratio), and a closed-loop testing procedure to compare models' log-likelihood and akaike information criterion scores.

RESULTS

In 26,474 singleton pregnancies (4,756, 18% with GDM), the original model demonstrated reasonable temporal validation (c-statistic = 0.698) but suboptimal calibration (expected-observed ratio = 0.485). Updated model C2 was preferred, with a high c-statistic (0.732) and significantly better performance in closed testing.

CONCLUSION

We demonstrated updating methods to sustain predictive performance in a contemporary population, highlighting the value and versatility of prediction models for guiding risk-stratified GDM care.

Predicting adverse perinatal outcomes among gestational diabetes complicated pregnancies using neural network algorithm

OBJECTIVE

The primary aim of this study is to utilize a neural network model to predict adverse neonatal outcomes in pregnancies complicated by gestational diabetes (GDM).

DESIGN

Our model, based on XGBoost, was implemented using Python 3.6 with the Keras framework built on TensorFlow by Google. We sourced data from medical records of GDM-diagnosed individuals who delivered at our tertiary medical center between 2012 and 2016. The model included simple pregnancy parameters, maternal age, body mass index (BMI), parity, gravity, results of oral glucose tests, treatment modality, and glycemic control. The composite neonatal adverse outcomes defined as one of the following: large or small for gestational age, shoulder dystocia, fetal umbilical pH less than 7.2, neonatal intensive care unit (NICU) admission, respiratory distress syndrome (RDS), hyperbilirubinemia, or polycythemia. For the machine training phase, 70% of the cohort was randomly chosen. Each sample in this set consisted of baseline parameters and the composite outcome. The remaining samples were then employed to assess the accuracy of our model.

RESULTS

The study encompassed a total of 452 participants. The composite adverse outcome occurred in 29% of cases. Our model exhibited prediction accuracies of 82% at the time of GDM diagnosis and 91% at delivery. The factors most contributing to the prediction model were maternal age, pre-pregnancy BMI, and the results of the single 3-h 100 g oral glucose tolerance test.

CONCLUSION

Our advanced neural network algorithm has significant potential in predicting adverse neonatal outcomes in GDM-diagnosed individuals.

Effectiveness of Lifestyle Interventions during Pregnancy on Preventing Gestational Diabetes Mellitus in High-Risk Women: A Systematic Review and Meta-Analyses of Published RCTs

BACKGROUND

Until now, it is uncertain whether lifestyle interventions during pregnancy can prevent gestational diabetes mellites (GDM) in high-risk pregnant women.

OBJECTIVE

This study aims at investigating the effectiveness of dietary interventions and/or exercise interventions during pregnancy for preventing GDM in high-risk pregnant women.

MATERIALS AND METHODS

Eligible randomized controlled trials (RCTs) were selected after a search in CENTRAL, Scopus, and PubMed. Synthesis was performed for the outcome of GDM in women with any identified GDM risk factor. Separate meta-analyses (MA) were performed to assess the efficacy of either nutrition or physical activity (PA) interventions or both combined compared with standard prenatal care for preventing GDM. Subgroup and sensitivity analyses, as well as meta-regressions against OR, were performed to assess potentional heterogeneity. Overall quality, the quality of RCTs, and publication bias were also evaluated.

RESULTS

A total of 13,524 participants comprising high-risk pregnant women in 41 eligible RCTs were analyzed for GDM. Women receiving only a nutrition intervention during pregnancy were less likely to experience GDM compared with women following standard prenatal care. Among 3109 high-risk pregnant women undergoing only dietary intervention for preventing GDM, 553 (17.8%) developed GDM; however, the result of the MA was marginally not significant (OR 0.73, 95%CI 0.51, 1.03; p-value 0.07), (Q 21.29, p-value 0.01; I2 58% (95%CI 10, 78%)). Subgroup analyses demonstrated an effect for studies that were conducted in Great Britain (OR 0.65, 95%CI 0.49, 0.81; p-value 0.003), and in Spain (OR 0.50, 95%CI 0.27, 0.94; p-value 0.03), for studies with forms of the Mediterranean diet as the intervention's component (OR 0.61; 95%CI 0.46, 0.81; p-value 0.0005), and for studies including a motivation arm in the intervention (OR 0.71, 95%CI 0.58, 0.87; p-value 0.0008). Among 2742 high-risk pregnant women being analyzed for GDM outcome after receiving only an exercise intervention, 461 (16.8%) were diagnosed with GDM. Women after receiving PA intervention were less likely to develop GDM (OR 0.64, 95%CI 0.51, 0.80; p-value < 0.0001), (Q 11.27, p-value 0.51; I2 0% (95%CI 0, 99%)). Finally, 1308 (17%) cases of GDM were diagnosed among 7673 high-risk pregnant women undergoing both diet and PA intervention. Women in the group of mixed lifestyle intervention had a significant reduction in incidence of GDM (OR 0.70, 95%CI 0.55, 0.90; p-value 0.005), (Q 50.32, p-value < 0.0001, I2 66%, (95% CI 44, 79%)).

CONCLUSIONS

The results of this study support the efficacy of lifestyle interventions during pregnancy for preventing GDM in high-risk women if an exercise component is included in the intervention arm, either alone, or combined with diet. A combined lifestyle intervention including physical exercise and a Mediterranean diet accompanied by motivation support may be considered the most effective way to prevent GDM among high-risk women during pregnancy. Future research is needed to strengthen these findings.

Associations of a current Australian model of dietetic care for women diagnosed with gestational diabetes and maternal and neonatal health outcomes

BACKGROUND

Gestational diabetes mellitus (GDM) is a significant public health burden in Australia. Subsequent strain on healthcare systems is widespread and current models of care may not be adequate to provide optimal healthcare delivery. This study aimed to assess a current model of dietetic care with maternal and neonatal outcomes.

METHODS

Hospital medical record data from The Women's Hospital, Melbourne, for women with GDM (n = 1,185) (July 2105-May 2017) was retrospectively analysed. Adjusted linear and logistic regression were used to analyse associations between the number of dietitian consultations and maternal and neonatal health outcomes.

RESULTS

Half of all women (50%) received two consultations with a dietitian. 19% of women received three or more consultations and of these women, almost twice as many were managed by medical nutrition therapy (MNT) and pharmacotherapy (66%) compared with MNT alone (34%). Higher odds of any maternal complication among women receiving 3 + consultations compared to those receiving zero (OR = 2.33 [95% CI: 1.23, 4.41], p = 0.009), one (OR = 1.80 [95% CI: 1.09, 2.98], p = 0.02), or two (OR = 1.65 [95% CI: 1.04, 2.60], p = 0.03) consultations were observed. Lower odds of infant admission to the Neonatal Intensive Care Unit (NICU) were observed among women receiving one (OR = 0.38 [95% CI: 0.18, 0.78], p = 0.008), two (OR = 0.37 [95% CI: 15 0.19, 0.71], p = 0.003), or three + consultations (OR = 0.43 [95% CI: 0.21, 0.88], p = 0.02), compared to no consultations.

CONCLUSION

The optimal schedule of dietitian consultations for women with GDM in Australia remains largely unclear. Alternate delivery of education for women with GDM such as telehealth and utilisation of digital platforms may assist relieving pressures on the healthcare system and ensure optimal care for women during pregnancy.

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

BACKGROUND

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Screening for MAFLD: who, when and how?

Metabolic-associated fatty liver disease (MAFLD) is a highly prevalent disease with increasing prevalence worldwide. Currently, no universal screening methods have been standardized, even when this disease poses a major health burden. MAFLD as a spectrum of diseases can range from simple steatosis, and steatohepatitis to fibrosis and hepatocellular carcinoma. Its extra-hepatic manifestations are vast and include cardiovascular diseases, extra-hepatic malignancies, cognitive and respiratory alterations. Given its extensive damage targets as well as its high prevalence, timely identification of the high-risk population presenting metabolic dysfunction should undergo universal non-invasive screening methods, which can be carried out through blood tests, easy and effective imaging techniques, such as ultrasound, score calculation and general clinical information brought together from primary patient-physician contact.

Medical nutrition therapy for gestational diabetes mellitus in Australia: What has changed in 10 years and how does current practice compare with best practice?

BACKGROUND

The present study aimed to report Australian dietetic practice regarding management of gestational diabetes mellitus (GDM) and to make comparisons with the findings from a 2009 survey of dietitians and with the Academy of Nutrition and Dietetics Evidence-Based Nutrition Practice Guidelines (NPG).

METHODS

Cross-sectional surveys were conducted in 2019 and 2009 of dietitians providing medical nutrition therapy (MNT) to women with GDM in Australia. The present study compares responses on demographics, dietetic assessment and interventions, and guideline use in 2019 vs. 2009.

RESULTS

In total, 149 dietitians (2019) and 220 (2009) met survey inclusion criteria. In both surveys >60% of respondents reported dietary interventions aiming for >45% energy from carbohydrate, 15%-25% energy from protein and 15%-30% energy from fat. Many variations in MNT found in 2009 continued to be evident in 2019, including the percentage of energy from carbohydrate aimed for (30%-65% in 2019 vs. 20%-75% in 2009) and the wide range in the recommended minimum daily carbohydrate intake (40-220 and 60-300 g). Few dietitians reported aiming for the NPG minimum of 175 g of carbohydrate daily in both surveys (32% in 2019 vs. 26% in 2009). There were, however, some significant increases in MNT consistent with NPG recommendations in 2019 vs. 2009, including the minimum frequency of visits provided (49%, n = 61 vs. 33%, n = 69; p < 0.001) and provision of gestational weight gain advice (59%, n = 95 vs. 40%, n = 195; p < 0.05).

CONCLUSIONS

Although many dietitians continue to provide MNT consistent with existing NPG, there is a need to support greater uptake, especially for recommendations regarding carbohydrate intake.

Development, validation and clinical utility of a risk prediction model for adverse pregnancy outcomes in women with gestational diabetes: The PeRSonal GDM model

BACKGROUND

The ability to calculate the absolute risk of adverse pregnancy outcomes for an individual woman with gestational diabetes mellitus (GDM) would allow preventative and therapeutic interventions to be delivered to women at high-risk, sparing women at low-risk from unnecessary care. We aimed to develop, validate and evaluate the clinical utility of a prediction model for adverse pregnancy outcomes in women with GDM.

METHODS

A prediction model development and validation study was conducted on data from a observational cohort. Participants included all women with GDM from three metropolitan tertiary teaching hospitals in Melbourne, Australia. The development cohort comprised those who delivered between 1 July 2017 to 30 June 2018 and the validation cohort those who delivered between 1 July 2018 to 31 December 2018. The main outcome was a composite of critically important maternal and perinatal complications (hypertensive disorders of pregnancy, large-for-gestational age neonate, neonatal hypoglycaemia requiring intravenous therapy, shoulder dystocia, perinatal death, neonatal bone fracture and nerve palsy). Model performance was measured in terms of discrimination and calibration and clinical utility evaluated using decision curve analysis.

FINDINGS

The final PeRSonal (Prediction for Risk Stratified care for women with GDM) model included body mass index, maternal age, fasting and 1-hour glucose values (75-g oral glucose tolerance test), gestational age at GDM diagnosis, Southern and Central Asian ethnicity, East Asian ethnicity, nulliparity, past delivery of an large-for-gestational age neonate, past pre-eclampsia, GWG until GDM diagnosis, and family history of diabetes. The composite adverse pregnancy outcome occurred in 27% (476/1747) of women in the development (1747 women) and in 26% (244/955) in the validation (955 women) cohorts. The model showed excellent calibration with slope of 0.99 (95% CI 0.75 to 1.23) and acceptable discrimination (c-statistic 0.68; 95% CI 0.64 to 0.72) when temporally validated. Decision curve analysis demonstrated that the model was useful across a range of predicted probability thresholds between 0.15 and 0.85 for adverse pregnancy outcomes compared to the alternatives of managing all women with GDM as if they will or will not have an adverse pregnancy outcome.

INTERPRETATION

The PeRSonal GDM model comprising of routinely available clinical data shows compelling performance, is transportable across time, and has clinical utility across a range of predicted probabilities. Further external validation of the model to a more disparate population is now needed to assess the generalisability to different centres, community based care and low resource settings, other healthcare systems and to different GDM diagnostic criteria.

FUNDING

This work is supported by the Mothers and Gestational Diabetes in Australia 2 NHMRC funded project #1170847.

Clinicians' perspectives on gestational diabetes screening during the global COVID-19 pandemic in Australia

AIM

There is no international consensus for the screening and diagnosis of gestational diabetes mellitus (GDM). In March 2020, modified screening and diagnostic recommendations were rapidly implemented in Queensland, Australia, in response to the COVID-19 pandemic. How clinicians perceived and used these changes can provide insights to support high-quality clinical practice and provide lessons for future policy changes. The aim of this study was to understand clinicians' perceptions and use of COVID-19 changes to GDM screening and diagnostic recommendations.

METHODS

Queensland healthcare professionals responsible for diagnosing or caring for women with GDM were recruited for semi-structured telephone interviews. Data analysis of transcribed interviews used inductive reflexive thematic analysis.

RESULTS

Seventeen interviews were conducted with the following participants: six midwives/nurses, three endocrinologists, two general practitioners, two general practitioners/obstetricians, two diabetes educators, one dietitian and one obstetrician. Three themes emerged: communication and implementation, perceptions and value of evidence and diversity in perceptions of GDM screening. Overall, clinicians welcomed the rapid changes during the initial uncertainty of the pandemic, but as COVID-19 became less of a threat to the Queensland healthcare system, some questioned the underlying evidence base. In areas where GDM was more prevalent, clinicians more frequently worried about missed diagnoses, whereas others who felt that overdiagnosis had occurred in the past continued to support the changes.

CONCLUSIONS

These findings highlight the challenges to changing policy when clinicians have diverse (and often strongly held) views.

Gestational diabetes screening from the perspective of consumers: Insights from early in the COVID-19 pandemic and opportunities to optimise experiences

BACKGROUND

Consumer perspectives are a cornerstone of value-based healthcare. Screening and diagnosis of gestational diabetes mellitus (GDM) were among many of the rapid changes to health care recommended during the COVID-19 pandemic. The changes provided a unique opportunity to add information about women's perspectives on the debate on GDM screening.

AIMS

The aim of this qualitative study was to explore women's perspectives and understanding of GDM screening and diagnosis comparing the modified COVID-19 recommendations to standard GDM screening and diagnostic practices.

METHODS

Women who had experienced both the standard and modified GDM screening and diagnostic processes were recruited for telephone interviews. Data analysis used inductive reflexive thematic analysis. Online surveys were disseminated to any registrant not included in interviews to provide an opportunity for all interested participants to provide their perspective.

RESULTS

Twenty-nine telephone interviews were conducted and 19 survey responses were received. Seven themes were determined: (1) information provision from clinicians; (2) acceptability of GDM screening; (3) individualisation of GDM screening methods; (4) safety nets to avoid a missed diagnosis; (5) informed decision making; (6) women want information and evidence; and (7) preferred GDM screening methods for the future.

CONCLUSIONS

Overall, women preferred the modified GDM screening recommendations put in place due to the COVID-19 pandemic. However, their preference was influenced by their prior screening experience and perception of personal risk profile. Women expressed a strong need for clear communication from health professionals and the opportunity to be active participants in decision making.

Impact of new diagnostic pathway for gestational diabetes in time of COVID-19

Background

In April 2020, the diagnostic criteria for gestational diabetes mellitus (GDM) changed in Queensland, with the goal of reducing exposure of pregnant women to COVID-19.

Methods

A retrospective clinical audit was conducted at a regional hospital to compare the incidence of GDM, and specific maternal and neonatal outcomes four months before and after the change in guidelines was implemented.

Results

Less than 50% of diagnostic tests were performed according to new guidelines. There was a non-significant increase in the incidence of GDM (13.3% to 15.3%), and pharmacological treatments. Instrumental deliveries (p = 0.01) and shoulder dystocia (p = 0.04) increased following the change in guidelines. There were no differences in the incidence of elective and emergency caesarean delivery, macrosomia and fetal weight. Maternal pre-pregnancy body mass index (BMI) was higher in the COVID-19 GDM cohort (p = 0.02).

Conclusions

Despite the change in guidelines, there was a non-significant increase in the incidence of diagnosis of gestational diabetes.

Risk stratification of women with gestational diabetes mellitus using mutually exclusive categories based on the International Association of Diabetes and Pregnancy Study Groups criteria for the development of postpartum dysglycaemia: a retrospective cohort study

OBJECTIVES

Women with gestational diabetes mellitus (GDM) are more predisposed to develop postpartum diabetes mellitus (DM). This study aimed to estimate the relative risk (RR) of postpartum dysglycaemia (prediabetes and DM) using mutually exclusive categories according to the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria cut-off points in patients with GDM, so as to establish a risk-stratification method for developing GDM management strategies.

DESIGN, SETTING AND PARTICIPANTS

In this retrospective cohort study, 942 women who had been diagnosed with GDM (IADPSG criteria) at 24-28 weeks of gestation from November 2016 to April 2018 underwent a 75 g oral glucose tolerance test (OGTT) at 6-12 weeks postpartum in a tertiary hospital of Singapore. Seven mutually exclusive categories (three one timepoint positive categories (fasting, 1 hour and 2 hours), three two timepoint positive categories (fasting+1 hour, fasting+2 hours and 1 hour+2 hours) and one three timepoint positive category (fasting+1 hour+2 hours)) were derived from the three timepoint antenatal OGTT according to the IADPSG criteria. To calculate the RRs of postpartum dysglyceamia of each mutually exclusive group, logistic regression was applied.

RESULTS

924 mothers with GDM, whose mean age was 32.7±4.7 years, were mainly composed of Chinese (45.4%), Malay (21.7%) and Indian (14.3%) ethnicity. The total prevalence of postnatal dysglycaemia was 16.7% at 6-12 weeks postpartum. Stratifying subjects into seven mutually exclusive categories, the RRs of the one-time, two-time and three-time positive groups of the antenatal OGTT test were 1.0 (Ref.), 2.0 (95% CI=1.3 to 3.1; p=0.001) and 6.7 (95% CI=4.1 to 10.9; p<0.001), respectively, which could be used to categorise patients with GDM into low-risk, intermediate-risk and high-risk group.

CONCLUSIONS

Mutually exclusive categories could be useful for risk stratification and early management of patients with prenatal GDM. It is plausible and can be easily translated into clinical practice.

Immunobiology of Gestational Diabetes Mellitus in Post-Medawar Era

Although the concepts related to fetal immune tolerance proposed by Sir Peter Medawar in the 1950s have not withstood the test of time, they revolutionized our current understanding of the immunity at the maternal-fetal interface. An important extension of the original Medawar paradigm is the investigation into the underlying mechanisms for adverse pregnancy outcomes, including recurrent spontaneous abortion, preterm birth, preeclampsia and gestational diabetes mellitus (GDM). Although a common pregnancy complication with systemic symptoms, GDM still lacks understanding of immunological perturbations associated with the pathological processes, particularly at the maternal-fetal interface. GDM has been characterized by low grade systemic inflammation that exacerbates maternal immune responses. In this regard, GDM may also entail mild autoimmune pathology by dysregulating circulating and uterine regulatory T cells (Tregs). The aim of this review article is to focus on maternal-fetal immunological tolerance phenomenon and discuss how local or systemic inflammation has been programmed in GDM. Specifically, this review addresses the following questions: Does the inflammatory or exhausted Treg population affecting the Th17:Treg ratio lead to the propensity of a pro-inflammatory environment? Do glycans and glycan-binding proteins (mainly galectins) contribute to the biology of immune responses in GDM? Our understanding of these important questions is still elementary as there are no well-defined animal models that mimic all the features of GDM or can be used to better understand the mechanistic underpinnings associated with this common pregnancy complication. In this review, we will leverage our preliminary studies and the literature to provide a conceptualized discussion on the immunobiology of GDM.

The Perspectives of Diabetes Educators and Dietitians on Diet and Lifestyle Management for Gestational Diabetes Mellitus: A Qualitative Study

This study explores the knowledge and practice of diabetes educators and dietitians on diet and lifestyle management in women with gestational diabetes mellitus (GDM). Diabetes educators and dietitians were recruited from three maternity hospitals in Adelaide (Australia), through snowball and purposive sampling. Thirteen semistructured interviews were conducted, audio recorded, transcribed verbatim, and analysed for codes and themes. Four themes emerged: guidelines and resources, dietary intervention, management delivery, and communication. Diabetes educators and dietitians demonstrated consistent knowledge of nutritional management for GDM and uniform delivery methods. However, a lack of culturally diverse resources was highlighted, along with a lack of continuity of care across the multidisciplinary team. Barriers towards uptake of dietary intervention were reflected by diabetes educators and dietitians as women showing signs of guilt and stress and disengaging from the service. Further exploration on the knowledge and practice of diabetes educators and dietitians for GDM to best inform implementation strategies for knowledge translation of nutritional management is needed. The indication of language and cultural barriers and resources highlight an ongoing key priority area to support the care of women of ethnic minorities.

Perinatal outcomes associated with the diagnosis of gestational diabetes: Systematic review and meta-analysis

OBJECTIVE

To compare perinatal outcomes in pregnant women diagnosed with gestational diabetes using the one-step and the two-step test.

METHODS

Meta-analysis of observational studies pregnancies women with gestational diabetes from January 2014 to February 2019. The outcomes studied were induction of labor and delivery, preterm delivery, fetal macrosomia, neonatal hypoglycemia, hyperbilirubinemia, low birth weight, and admission to the neonatal intensive care unit.

RESULTS

Eight studies were included with a population of 108,609 pregnancies. Statistical differences were obtained for fetal macrosomia RR0.9 (95%CI0.85-0.97; I²0%) and neonatal hypoglycemia RR1.1 (95%CI1.01-1.40; I²48.5%).

CONCLUSION

Neonatal macrosomia appears to be less present when the one-step diagnostic test is used and neonatal hypoglycemia was lower with the two-step test. Register PROSPERO CRD42020215062.

An Update on Screening Strategies for Gestational Diabetes Mellitus: A Narrative Review

Gestational diabetes mellitus (GDM) is a frequent medical complication during pregnancy. Screening and diagnostic practices for GDM are inconsistent across the world. This narrative review includes data from 87 observational studies and randomized controlled trials (RCTs), and aims to give an overview of the current evidence on screening strategies and diagnostic criteria for GDM. Screening in early pregnancy remains controversial and studies show conflicting results on the benefit of screening and treatment of GDM in early pregnancy. Implementing the one-step "International Association of Diabetes and Pregnancy Study Groups" (IADPSG) screening strategy at 24-28 weeks often leads to a substantial increase in the prevalence of GDM, without conclusive evidence regarding the benefits on pregnancy outcomes compared to a two-step screening strategy with a glucose challenge test (GCT). In addition, RCTs are needed to investigate the impact of treatment of GDM diagnosed with IADPSG criteria on long-term maternal and childhood outcomes. Selective screening using a risk-factor-based approach could be helpful in simplifying the screening algorithm but carries the risk of missing significant proportions of GDM cases. A two-step screening method with a 50g GCT and subsequently a 75g oral glucose tolerance test (OGTT) with IADPSG could be an alternative to reduce the need for an OGTT. However, to have an acceptable sensitivity to screen for GDM with the IADPSG criteria, the threshold of the GCT should be lowered from 7.8 to 7.2 mmol/L. A pragmatic approach to screen for GDM can be implemented during the COVID-19 pandemic, using fasting plasma glucose (FPG), HbA1c or even random plasma glucose (RPG) to reduce the number of OGTTs needed. However, usual guidelines and care should be resumed as soon as the COVID pandemic is controlled.

Estimated impact of introduction of new diagnostic criteria for gestational diabetes mellitus

BACKGROUND

Implementation of new diagnostic criteria for gestational diabetes mellitus (GDM) are still a subject of debate, mostly due to concerns regarding the effects on the number of women diagnosed with GDM and the risk profile of the women newly diagnosed.

AIM

To estimate the impact of the World Health Organization (WHO) 2013 criteria compared with the WHO 1999 criteria on the incidence of gestational diabetes mellitus as well as to determine the diagnostic accuracy for detecting adverse pregnancy outcomes.

METHODS

We retrospectively analyzed a single center Dutch cohort of 3338 women undergoing a 75 g oral glucose tolerance test where the WHO 1999 criteria to diagnose GDM were clinically applied. Women were categorized into four groups: non-GDM by both criteria, GDM by WHO 1999 only (excluded from GDM), GDM by WHO 2013 only (newly diagnosed) and GDM by both criteria. We compared maternal characteristics, pregnancy outcomes and likelihood ratios for adverse pregnancy outcomes.

RESULTS

Retrospectively applying the WHO 2013 criteria increased the cohort incidence by 13.1%, from 19.3% to 32.4%. Discordant diagnoses occurred in 21.3%; 4.1% would no longer be labelled as GDM, and 17.2% were newly diagnosed. Compared to the non-GDM group, women newly diagnosed were older, had higher rates of obesity, higher diastolic blood pressure and higher rates of caesarean deliveries. Their infants were more often delivered preterm, large-for-gestational-age and were at higher risk of a 5 min Apgar score < 7. Women excluded from GDM were older and had similar pregnancy outcomes compared to the non-GDM group, except for higher rates of shoulder dystocia (4.3% vs 1.3%, P = 0.015). Positive likelihood ratios for adverse outcomes in all groups were generally low, ranging from 0.54 to 2.95.

CONCLUSION

Applying the WHO 2013 criteria would result in a substantial increase in GDM diagnoses. Newly diagnosed women are at increased risk for pregnancy adverse outcomes. This risk, however, seems to be lower than those identified by the WHO 1999 criteria. This could potentially influence the treatment effect that can be achieved in this group. Evidence on treatment effects in newly diagnosed women is urgently needed.

Are newly introduced criteria for the diagnosis of gestational diabetes mellitus associated with improved pregnancy outcomes and/or increased interventions in New South Wales, Australia? A population-based data linkage study

INTRODUCTION

The incidence of gestational diabetes mellitus (GDM) is increasing in Australia, influenced by changed diagnostic criteria. We aimed to identify whether the diagnostic change was associated with improved outcomes and/or increased obstetric interventions using state-wide data in New South Wales (NSW), Australia.

RESEARCH DESIGN AND METHODS

Perinatal and hospital data were linked for singleton births, 33-41 weeks' gestation, 2006-2015, NSW. An adjusted Poisson model was used to split pregnancies from 2011 onwards into those that would have been diagnosed under the old criteria ('previous GDM') and newly diagnosed cases ('additional GDM'). We compared actual rates of total and early (<39 weeks) planned births, cesareans, and maternal and neonatal adverse outcomes for GDM-diagnosed pregnancies using three predicted scenarios, where the 'additional GDM' group was assumed to have the same rates as: the 'previous GDM' group <2011 (scenario A); the 'non-GDM' group <2011 (scenario B); or the 'non-GDM' group ≥2011 (scenario C).

RESULTS

GDM incidence more than doubled over the study period, with an inflection point observed at 2011. For those diagnosed with GDM since 2011, the actual incidence of interventions (planned births and cesareans) and macrosomia was consistent with scenario A, which meant higher intervention rates, but lower rates of macrosomia, than those with no GDM. Incidence of neonatal hypoglycemia was lower than scenario A and closer to the other scenarios. There was a reduction in perinatal deaths among those with GDM, lower than that predicted by all scenarios, indicating an improvement for all with GDM, not only women newly diagnosed. Incidence of maternal and neonatal morbidity indicators was within the confidence bounds for all three predicted scenarios.

CONCLUSIONS

Our study suggests that the widely adopted new diagnostic criteria for GDM are associated with increased obstetric intervention rates and lower rates of macrosomic babies, but with no clear impacts on maternal or neonatal morbidity.

Metabolomic Biomarkers in Gestational Diabetes Mellitus: A Review of the Evidence

Gestational diabetes mellitus (GDM) is the fastest growing type of diabetes, affecting between 2 to 38% of pregnancies worldwide, varying considerably depending on diagnostic criteria used and sample population studied. Adverse obstetric outcomes include an increased risk of macrosomia, and higher rates of stillbirth, instrumental delivery, and birth trauma. Metabolomics, which is a platform used to analyse and characterise a large number of metabolites, is increasingly used to explore the pathophysiology of cardiometabolic conditions such as GDM. This review aims to summarise metabolomics studies in GDM (from inception to January 2021) in order to highlight prospective biomarkers for diagnosis, and to better understand the dysfunctional metabolic pathways underlying the condition. We found that the most commonly deranged pathways in GDM include amino acids (glutathione, alanine, valine, and serine), carbohydrates (2-hydroxybutyrate and 1,5-anhydroglucitol), and lipids (phosphatidylcholines and lysophosphatidylcholines). We also highlight the possibility of using certain metabolites as predictive markers for developing GDM, with the use of highly stratified modelling techniques. Limitations for metabolomic research are evaluated, and future directions for the field are suggested to aid in the integration of these findings into clinical practice.

Trends and characteristics of women undergoing induction of labour in a tertiary hospital setting: A cross-sectional study

BACKGROUND

In many well-resourced countries, rising rates of intervention are being observed during pregnancy, labour and childbirth with induction of labour (IOL) fast becoming one of the most common. In Australia, the rate of induction of labour has increased by over 30% since 2007, and today one in three women have their labours induced. We do not however have a good understanding of the contribution of specific obstetric populations to this trend.

METHODS

We examine the contribution of specific obstetric populations to induction of labour over a six-year period at one tertiary maternity service, using the Nippita classification system. Average Annual Percentage Changes (AAPC) were calculated along with 95% confidence intervals and P values set at 0.05.

RESULTS

The overall rate of induction of labour increased from 21.3% in 2012 to 30.9% in 2017, representing an Average Annual Percent Change of 8.1, P<0.0001 (95% CI 7-9.6). The greatest AAPC was seen in group 5 (parous, no previous caesarean section, 39-40 weeks, single cephalic), followed by group 2 (nulliparous, 39-40 weeks, single cephalic) and 1 (nulliparous, 37-38 weeks, single cephalic).

CONCLUSIONS

The use of the Nippita classification system allowed for standardised comparison across timepoints, facilitating identification of the subpopulations driving changes in rates of induction of labour. Rates of induction of labour saw a year on year increase which in this maternity service, it is not being driven by post-dates pregnancies. Further work is required to understand the role of other potential contributors such as diabetes.

Resolving the Gestational Diabetes Diagnosis Conundrum: The Need for a Randomized Controlled Trial of Treatment

The diagnosis of and criteria for gestational diabetes mellitus (GDM) continue to divide the scientific and medical community, both between and within countries. Many argue for universal adoption of the International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria and feel that further clinical trials are unjustified and even unethical. However, there are concerns about the large increase in number of women who would be diagnosed with GDM using these criteria and the subsequent impact on health care resources and the individual. This Perspective reviews the origins of the IADPSG consensus and points out some of its less well-known limitations, particularly with respect to identifying women at risk for an adverse pregnancy outcome. It also questions the clinical and cost-effectiveness data often cited to support the IADPSG glycemic thresholds. We present the argument that adoption of diagnostic criteria defining GDM should be based on response to treatment at different diagnostic thresholds of maternal glycemia. This will likely require an international multicenter trial of treatment.

Economic Evaluations of Gestational Diabetes Mellitus Screening: A Systematic Review

BACKGROUND

This study aims to find evidence of the cost-effectiveness of gestational diabetes mellitus (GDM) screening and assess the quality of current economic evaluations, which have shown different conclusions with a variation in screening methods, data sources, outcome indicators, and implementation in diverse organizational contexts.

METHODS

Embase, Medline, Web of Science, Health Technology Assessment, database, and National Health Service Economic Evaluation Database databases were searched through June 2019. Studies on economic evaluation reporting both cost and health outcomes of GDM screening programs in English language were selected, and the quality of the studies was assessed using Drummond's checklist. The general characteristics, main assumptions, and results of the economic evaluations were summarized.

RESULTS

Our search yielded 10 eligible economic evaluations with different screening strategies compared in different settings and perspectives. The selected papers scored 81% (68-97%) on the items in Drummond's checklist on average. In general, a screening program is cost-effective or even dominant over no screening. The one-step screening, with more cases detected, is more likely to be cost-effective than the two-step screening. Universal screening is more likely to be cost-effective than screening targeting the high-risk population. Parameters affecting cost-effectiveness include: diagnosis criteria, epidemiological characteristics of the population, efficacy of screening and treatment, and costs.

CONCLUSIONS

Most studies found GDM screening to be cost-effective, though uncertainties remain due to many factors. The quality assessment identified weaknesses in the economic evaluations in terms of integrating existing data, measuring costs and consequences, analyzing perspectives, and adjusting for uncertainties.

Searching for Utopia, the Challenge of Standardized Medical Nutrition Therapy Prescription in Gestational Diabetes Mellitus Management: A Critical Review

Gestational diabetes mellitus (GDM) is a common pregnancy disorder and the incidence is increasing worldwide. GDM is associated with adverse maternal outcomes which may be reduced with proper management. Lifestyle modification in the form of medical nutrition therapy and physical activity, as well as self-monitoring of blood glucose levels, is the cornerstone of GDM management. Inevitably, the search for the "ultimate" diet prescription has been ongoing. Identifying the amount and type of carbohydrate to maintain blood glucose levels below targets while balancing the nutritional requirements of pregnancy and achieving gestational weight gain within recommendations is challenging. Recent developments in the area of the gut microbiota and its impact on glycemic response add another layer of complexity to the success of medical nutrition therapy. This review critically explores the challenges to dietary prescription for GDM and why utopia may never be found.

A Review of the Current Status of Gestational Diabetes Mellitus in Australia-The Clinical Impact of Changing Population Demographics and Diagnostic Criteria on Prevalence

The current status of gestational diabetes mellitus in Australia reveals an almost quadrupling prevalence over the last decade. A narrative review of the current Australian literature reveals unique challenges faced by Australian maternity clinicians when addressing this substantial disease burden in our diverse population. Rising rates of maternal overweight and obesity, increasing maternal age and the diversity of ethnicity are key epidemiological impactors, overlaid by the 2015 changes in screening and diagnostic parameters. Our vast land mass and the remote location of many at risk women requires innovative and novel ideas for pathways to diagnose and effectively manage women with gestational diabetes mellitus. By modifying and modernizing models of care for women with gestational diabetes mellitus, we have the ability to address accessibility, resource management and our acute response to global events such as the COVID 19 pandemic. With continuing research, education and robust discourse, Australia is well placed to meet current and future challenges in the management of gestational diabetes mellitus.

Effects of Changing Diagnostic Criteria for Gestational Diabetes Mellitus in Queensland, Australia

OBJECTIVE

To evaluate the effects of updated gestational diabetes mellitus (GDM) screening and diagnostic criteria on selected perinatal outcomes in Queensland, Australia.

METHODS

This was a pre-post comparison study using perinatal data the year before (2014) and after (2016) the screening and diagnostic criteria for GDM was changed in Queensland, Australia. In 2015, Queensland adopted the one-step screening and diagnostic criteria based on the International Association of the Diabetes and Pregnancy Study Groups' recommendations. The data from 62,517 women in 2014 and 61,600 women in 2016 who gave birth from 24 weeks of gestation were analyzed in three groups in each year: women with GDM; women without diagnosed GDM; and total population. The outcome measures were gestational hypertension, cesarean birth, gestational age at delivery, birth weight, preterm delivery, large-for-gestational age (LGA) neonates, small-for-gestational-age (SGA) neonates, neonatal hypoglycemia, and respiratory distress.

RESULTS

The diagnosis of GDM increased from 8.7% (n=5,462) to 11.9% (n=7,317). After changing the diagnostic criteria, the changes to outcomes, odds ratios (OR), and adjusted odds ratios (aOR) (95% CI) for outcomes with statistically significant differences for the total population were: gestational hypertension 4.6% vs 5.0%, OR 1.09 (1.03-1.15), aOR 1.07 (1.02-1.13); preterm birth 7.6% vs 8.0%, OR 1.05 (1.01-1.09), aOR 1.06 (1.02-1.10); neonatal hypoglycemia 5.3% vs 6.8%, OR 1.31 (1.25-1.37), aOR 1.32 (1.25-1.38); and respiratory distress 6.2% vs 6.0%, OR 0.96 (0.91-1.00), aOR 0.94 (0.89-0.99). There was no change to cesarean births or LGA or SGA neonates for women with or without diagnosed GDM or the total population.

CONCLUSION

Except for a very small decrease in respiratory distress, changing the diagnostic criteria has resulted in more GDM diagnoses with no observed changes to measured perinatal outcomes for women with and without diagnosed GDM.

ENDOCRINOLOGY IN THE TIME OF COVID-19: Diagnosis and management of gestational diabetes mellitus

The COVID-19 pandemic has required rapid transformation and adaptation of healthcare services. Women with gestational diabetes mellitus (GDM) are one of the largest high-risk groups accessing antenatal care. In reformulating the care offered to those with GDM, there is a need to balance the sometimes competing requirement of lowering the risk of direct viral transmission against the potential adverse impact of service changes. We suggest pragmatic options for screening of GDM in a pandemic setting based on blood tests, and risk calculators applied to underlying risk factors. Alternative models for antenatal care provision for women with GDM, including targeting high-risk groups, early lifestyle interventions and remote monitoring are provided. Testing options and their timing for postpartum screening in women who had GDM are also considered. Our suggestions are only applicable in a pandemic scenario, and usual guidelines and care pathways should be re-implemented as soon as possible and appropriate.

The diagnosis of gestational diabetes mellitus (GDM) using a 75 g oral glucose tolerance test: A prospective observational study

AIMS

Screening for Gestational Diabetes Mellitus (GDM) is controversial. This prospectivestudy compared different sets of diagnostic cut-off points for plasma glucose measurements following a 75 g Oral Glucose Tolerance Test (OGTT).

METHODS

Women who had maternal risk factors for GDM were recruited at their convenience attheir first prenatal visit and consented to a one-step OGTT at 26-28 weeks gestation.All women fulfilling the World Health Organization (WHO) 2013 diagnostic criteriareceived standard care for GDM.

RESULTS

Of the 202 women, 139 (69%) had one risk factor for GDM and 63 (31%) had > 1.Using the WHO criteria, 53% (n = 108) had GDM compared with 35% (n = 71) usingCanadian criteria and 18% (n=36) using National Institute for Health Care Excellencecriteria (NICE) criteria (both p<0.001). Of the 108 women, 50% (n = 54) requiredpharmacological treatment to control hyperglycaemia. If the Canadian criteria wereapplied, 11/54 (20.4%) women would not have received hypoglycaemics. If the NICEcriteria were applied, 36/54 (66.7%) women would not have received hypoglycaemics.Maternal insulin, HOMA-IR and C-peptide measured at the time of the OGTT showed evidence of increased insulin resistance in women who had GDM based on the WHOcriteria but who had a normal OGTT based on the Canadian or NICE criteria.

CONCLUSIONS

Under stringent research conditions, our study suggeststhat the Canadian and, in particular, the NICE criteria are not identifying women who may benefit fromimproved glycaemic control. These findings support the need for the planned review of the NICE guidelines on GDM in 2020.

Exploring women's priorities for the potential consequences of a gestational diabetes diagnosis: A pilot community jury

BACKGROUND

There is no international diagnostic agreement for gestational diabetes mellitus (GDM). In 2014, Australia adopted a new definition and testing procedure. Since then, significantly more women have been diagnosed with GDM but with little difference in health outcomes. We explored the priorities and preferences of women potentially impacted by a GDM diagnosis.

METHOD

We recruited 15 women from the Gold Coast, Australia, to participate in a pilot community jury (CJ). Over two days, the women deliberated on the following: (a) which important consequences of a diagnosis of GDM should be considered when defining GDM?; (b) what should Australian health practitioners call the condition known as GDM?

RESULTS

Eight women attended the pilot CJ, and their recommendations were a consensus. Women were surprised that the level of risk for physical harms was low but emotional harms were high. The final ranking of important consequences (high to low) was as follows: women's negative emotions; management burden of GDM; overmedicalized pregnancy; minimizing infant risks; improving lifestyle; and macrosomia. To describe the four different clinical states of GDM, the women chose three different labels. One was GDM.

CONCLUSIONS

The women from this pilot CJ prioritized the consequences of a diagnosis of GDM differently from clinicians. The current glucose threshold for GDM in Australia is set at a cut-point for adverse risks including macrosomia and neonatal hyperinsulinaemia. Definitions and guideline panels often fail to ask the affected public about their values and preferences. Community voices impacted by health policies should be embedded in the decision-making process.

Women's experiences of a diagnosis of gestational diabetes mellitus: a systematic review

Background

Gestational diabetes mellitus (GDM) - a transitory form of diabetes induced by pregnancy - has potentially important short and long-term health consequences for both the mother and her baby. There is no globally agreed definition of GDM, but definition changes have increased the incidence in some countries in recent years, with some research suggesting minimal clinical improvement in outcomes. The aim of this qualitative systematic review was to identify the psychosocial experiences a diagnosis of GDM has on women during pregnancy and the postpartum period.

Methods

We searched CINAHL, EMBASE, MEDLINE and PsycINFO databases for studies that provided qualitative data on the psychosocial experiences of a diagnosis of GDM on women across any stage of pregnancy and/or the postpartum period. We appraised the methodological quality of the included studies using the Critical Appraisal Skills Programme Checklist for Qualitative Studies and used thematic analysis to synthesis the data.

Results

Of 840 studies identified, 41 studies of diverse populations met the selection criteria. The synthesis revealed eight key themes: initial psychological impact; communicating the diagnosis; knowledge of GDM; risk perception; management of GDM; burden of GDM; social support; and gaining control. The identified benefits of a GDM diagnosis were largely behavioural and included an opportunity to make healthy eating changes. The identified harms were emotional, financial and cultural. Women commented about the added responsibility (eating regimens, appointments), financial constraints (expensive food, medical bills) and conflicts with their cultural practices (alternative eating, lack of information about traditional food). Some women reported living in fear of risking the health of their baby and conducted extreme behaviours such as purging and starving themselves.

Conclusion

A diagnosis of GDM has wide reaching consequences that are common to a diverse group of women. Threshold cut-offs for blood glucose levels have been determined using the risk of physiological harms to mother and baby. It may also be advantageous to consider the harms and benefits from a psychosocial and a physiological perspective. This may avoid unnecessary burden to an already vulnerable population.

Diagnostic Strategies for Gestational Diabetes Mellitus: Review of Current Evidence

PURPOSE OF REVIEW

Currently, the diagnosis of gestational diabetes mellitus (GDM) lacks uniformity. Several controversies are still under debate, especially on the method of screening and diagnosis. This review focuses on recent literature and provides current evidence for the screening and diagnosis of GDM.

RECENT FINDINGS

Selective screening would miss a significant number of women with GDM. In contrast, universal screening has been shown to be cost-effective, compared with selective screening, and is recommended by many medical societies. For the diagnostic methods for GDM, most observational cohort studies reported that the one-step method is associated with improved pregnancy outcomes and is cost-saving or cost-effective, compared with the two-step method, although these findings should be confirmed in the upcoming randomized controlled trials which compare the performance of one-step and two-step methods. On the other hand, the methods of early screening or diagnosis of GDM are varied, and current evidence does not justify their use during early pregnancy. In conclusion, current evidence favors universal screening for GDM using the one-step method. Early screening for GDM is not favorably supported by the literature.

Prognostic prediction models for pregnancy complications in women with gestational diabetes: a protocol for systematic review, critical appraisal and meta-analysis

BACKGROUND

Gestational diabetes (GDM) is increasingly common and has significant implications during pregnancy and for the long-term health of the mother and offspring. However, it is a heterogeneous condition with inter-related factors including ethnicity, body mass index and gestational weight gain significantly modifying the absolute risk of complications at an individual level. Predicting the risk of pregnancy complications for an individual woman with GDM presents a useful adjunct to therapeutic decision-making and patient education. Diagnostic prediction models for GDM are prevalent. In contrast, prediction models for risk of complications in those with GDM are relatively novel. This study will systematically review published prognostic prediction models for pregnancy complications in women with GDM, describe their characteristics, compare performance and assess methodological quality and applicability.

METHODS

Studies will be identified by searching MEDLINE and Embase electronic databases. Title and abstract screening, full-text review and data extraction will be completed independently by two reviewers. The included studies will be systematically assessed for risk of bias and applicability using appropriate tools designed for prediction modelling studies. Extracted data will be tabulated to facilitate qualitative comparison of published prediction models. Quantitative data on predictive performance of these models will be synthesised with meta-analyses if appropriate.

DISCUSSION

This review will identify and summarise all published prognostic prediction models for pregnancy complications in women with GDM. We will compare model performance across different settings and populations with meta-analysis if appropriate. This work will guide subsequent phases in the prognosis research framework: further model development, external validation and model updating, and impact assessment. The ultimate model will estimate the absolute risk of pregnancy complications for women with GDM and will be implemented into routine care as an evidence-based GDM complication risk prediction model. It is anticipated to offer value to women and their clinicians with individualised risk assessment and may assist decision-making. Ultimately, this systematic review is an important step towards a personalised risk-stratified model-of-care for GDM to allow preventative and therapeutic interventions for the maximal benefit to women and their offspring, whilst sparing expense and harm for those at low risk.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number CRD42019115223.

Detection, treatment and prevention programs for gestational diabetes mellitus: The St Carlos experience

Gestational diabetes mellitus (GDM) increases the risk of adverse events in pregnancy and jeopardizes long-term health of the mother and offspring. There is currently no consensus as to what screening strategies improve the efficiency of GDM diagnosis. Which criteria should be used? Is the one-step or two-step procedure better? There is no agreement as to what the best dietary approach in the treatment of GDM is. In addition, different nutritional interventions have been studied in the prevention of GDM. The Mediterranean diet seems to be effective in preventing GDM and other maternofoetal outcomes. We review herein our experience using the one-step criteria for GDM screening; the treatment and prevention strategies used; and the overall impact of nutrition on maternofoetal health.