Change in prevalence of gestational diabetes and obstetric complications when applying IADPSG screening criteria in a Belgian French speaking University Hospital. A retrospective cohort study

Predicting insulin use among women with gestational diabetes diagnosed in oral glucose tolerance test

BACKGROUND

Gestational diabetes mellitus (GDM) is one of the most common complications affecting pregnant women. While most women will achieve adequate glycemic levels with diet and exercise, some will require pharmacological treatment to reach and maintain glucose levels between the desired thresholds. Identifying these patients early in pregnancy could help direct resources and interventions.

METHODS

This retrospective cohort of women with GDM diagnosed with an abnormal 75g-OGTT presents data from 869 patients (724 in the diet group and 145 in the insulin group). Univariate logistic regression was used to compare the groups, and multivariable logistic regression was used to identify independent factors associated with the need for insulin. A log-linear function was used to estimate the probability of requiring pharmacological treatment.

RESULTS

Women in the insulin group had higher pre-pregnancy BMI index (29.8 vs 27.8 kg/m², odds ratio [OR] 1.06, 95% confidence interval [CI] 1.03-1.09), more frequent history of previous GDM (19.4% vs. 7.8%, OR 2.84, 95% CI 1.59-5.05), were more likely to have chronic hypertension (31.7% vs. 23.2%, OR 1.54, 95% CI 1.04-2.27), and had higher glucose levels at all three OGTT points. Multivariable logistic regression final model included age, BMI, previous GDM status, and the three OGTT values as predictors of insulin requirement.

CONCLUSIONS

We can use regularly collected data from patients (age, BMI, previous GDM status, and the three OGTT values) to calculate the risk of a woman with GDM diagnosed in OGTT needing insulin. Identifying patients with a greater risk of requiring pharmacological treatment could help healthcare services to better allocate resources and offer closer follow-up to high-risk patients.

Evolution of Gestational Diabetes Mellitus across Continents in 21st Century

Over the last few decades, several definitions of gestational diabetes mellitus (GDM) have been described. There is currently not enough research to show which way is the best to diagnose GDM. Opinions differ in terms of the optimal screening and diagnostic measures, in part due to the differences in the population risks, the cost-effectiveness considerations, and the lack of an evidence base to support large national screening programs. The basic method for identifying the disease is the measurement of glucose plasma levels which may be determined when fasting, two hours after a meal, or simply at any random time. The currently increasing incidence of diabetes in the whole population, the altering demographics and the presence of lifestyle changes still require better methods of screening for hyperglycemia, especially during pregnancy. The main aim of this review is to focus on the prevalence and modifications to the screening criteria for GDM across all continents in the 21st century. We would like to show the differences in the above issues and correlate them with the geographical situation. Looking at the history of diabetes, we are sure that more than one evolution in GDM diagnosis will occur, due to the development of medicine, appearance of modern technologies, and the dynamic continuation of research.

One-Step Compared With Two-Step Gestational Diabetes Screening and Pregnancy Outcomes: A Systematic Review and Meta-analysis

OBJECTIVE

To estimate short-term maternal and neonatal outcomes with one-compared with two-step testing for gestational diabetes mellitus (GDM).

DATA SOURCES

A systematic review of randomized controlled trials (RCTs) and observational studies comparing one-step and two-step GDM testing strategies before September 2021 was conducted. We searched Ovid Medline (1946-), EMBASE (1947-), Scopus (1960-), Cochrane Central, and ClinicalTrials.gov . The primary outcome was rate of large-for-gestational age (LGA) neonates. Secondary outcomes were clinically relevant outcomes for GDM that were selected a priori.

METHODS OF STUDY SELECTION

Titles, abstracts, and manuscripts were screened, selected, and reviewed by the first two authors. Four RCTs (24,966 patients) and 13 observational studies (710,677 patients) were analyzed.

TABULATION, INTEGRATION, AND RESULTS

Pooled relative risks (RRs) were calculated with 95% CIs using random-effects models and were plotted graphically with forest plots. Study heterogeneity was evaluated using Cochran Q and Higgins I 2 tests. The quality of studies that met the inclusion criteria was evaluated with the Downs and Black checklist. Publication bias was assessed by using asymmetry of funnel plots and Harbord's test. There was no difference in the rate of LGA neonates (pooled RR 0.95; 95% CI 0.88-1.04) by testing strategy among RCTs, but patients who underwent one-step testing were more likely to be diagnosed with GDM (pooled RR 2.13; 95% CI 1.61-2.82) and treated with diabetes medications (pooled RR 2.24; 95% CI 1.21-4.15). One-step testing was associated with higher rates of neonatal intensive care unit (NICU) admission (pooled RR 1.12; 95% CI 1.00-1.26) and neonatal hypoglycemia (pooled RR 1.23; 95% CI 1.13-1.34). In analysis of high-quality RCTs and observational studies, one-step testing was associated with a lower rate of LGA neonates (pooled RR 0.97; 95% CI 0.95-0.98), but higher rates of GDM diagnosis, treatment, NICU admission, and neonatal hypoglycemia.

CONCLUSION

Despite a significant increase in GDM diagnosis and treatment with one-step testing, there is no difference in rate of LGA neonates compared with two-step testing among RCTs.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42021252703.

Evolution of maternal and neonatal outcomes before and after the adoption of the IADPSG/WHO guidelines in Belgium: A descriptive study of 444,228 pregnancies

Objectives

To appraise adverse pregnancy outcomes after the adoption of IADPSG/WHO guidelines in Belgium.

Methods

A retrospective study of the Center for Perinatal Epidemiology registry was conducted. Demographic changes and adverse pregnancy outcomes were compared between a pre- and post-guideline period in women with and without hyperglycemia in pregnancy (HIP). Adjusted odds ratios with a 95% confidence interval (CI) were used to compare maternal and neonatal outcomes controlling for potential confounders (maternal age, body mass index (BMI), hypertension, parity, and multiple births).

Results

The prevalence of HIP increased (6.0%–9.2%). In the overall population regardless of glycemic status, gestational weight gain (12.3 ± 5.7 vs 11.9 ± 5.8; p < 0.001), hypertension (0.92; 95% CI, 0.89–0.94; p < 0.001), and neonatal intensive care unit/special care nursery (0.89; 95% CI, 0.87–0.91; p < 0.001) decreased despite increasing maternal age and pre-pregnancy BMI. Emergency cesarean section rates (1.07; 95% CI, 1.05–1.09; p < 0.001) increased, but not in the HIP population (1.02; 95% CI, 0.95–1.10; ns). The overall incidence of preterm birth (1.09; 95% CI, 1.06–1.12; p < 0.001), stillbirth (1.10; 95% CI, 1.01–1.21; p < 0.05), and perinatal mortality (1.10; 95% CI, 1.01–1.19; p < 0.05) increased, except in the HIP population (1.03; 95% CI, 0.95–1.11; ns), (1.04; 95% CI, 0.74–1.47; ns) and (1.09; 95% CI, 0.80–1.49; ns), respectively. The overall incidence of small- for-gestational-age remained unchanged (0.99; 95%CI, 0.97–1.01; ns) regardless of glycemic status. In the HIP population, large-for-gestational age (0.90; 95% CI, 0.84–0.95; p < 0.001) and macrosomia (0.84; 95% CI, 0.78–0.92; p < 0.001) decreased.

Conclusion

After the implementation of IADPSG/WHO guidelines, the prevalence of HIP increased by 53.7% and the incidence of major HIP-related pregnancy complications appears to be lower. However, we cannot conclude that the reduction of LGA-macrosomia is due to a better management of diabetes or due to greater recruitment of women with mild HIP associated with a lower risk of obstetrical complications.

A Prospective Study to Determine if Management of Cases of Gestational Diabetes Mellitus (GDM) can be Modified

Background

To study maternal-fetal outcomes in patients of GDM diagnosed by International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria but subsequently using a twenty-four-hour seven-value sugar profile to evaluate patients before instituting management.

Methods

This prospective observational study was conducted at a tertiary hospital in New Delhi, India, over a period of one year. During this period, women diagnosed as GDM between 24 and 28 weeks of gestation using IADPSG criteria underwent seven-value sugar profile in twenty-four hours before initiating any therapy. Those with normal profile were kept on observation only, whereas others were managed by Medical Nutrition Therapy (MNT) with or without pharmacotherapy as required to maintain euglycemia. Maternal and fetal outcomes were documented and analysed to detect differences between the groups.

Results

Out of 2279 pregnant women, 201 (8.8%) were diagnosed as GDM. The twenty-four-hour seven-value sugar profile was normal in 78 (38.8%) patients, who were managed only by close observation. Treatment was given to other patients; 93 (46.2%) patients were managed with MNT only, whereas pharmacotherapy by way of metformin was added to 22 (10.9%) patients and 8 (3.9%) patients required insulin. Differences in maternal-fetal outcomes between the treated and untreated groups were not found to be statistically significant.

Conclusions

The policy of evaluating patients with twenty-four-hour seven-value sugar profile after an abnormal Oral Glucose Tolerance Test eliminated over one-third women from receiving treatment and interventions for GDM without compromising maternal-fetal outcomes.

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.

Effect of the IADPSG screening strategy for gestational diabetes on perinatal outcomes in Switzerland

AIMS

To evaluate the impact adoption of the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria on prevalence of gestational diabetes mellitus (GDM) and risks of perinatal outcomes.

METHODS

Retrospectively, 155,103 women screened with selective two step criteria in Switzerland in period 1 (2005-2010) were compared to 170,427 women screened with IADPSG criteria in period 2 (2012-2017). GDM prevalence over time was established and multivariable regression used to assess variation in risks for GDM related events and perinatal outcomes.

RESULTS

GDM prevalence increased steadily over both study periods from 1.8% to 9.0%. A risk reduction of GDM-related events was shown only for women with one or two risk factors for GDM present (relative risk (95% confidence interval)): (0.93 (0.90,0.97), 0.90 (0.83,0.96)). The comparison of perinatal outcomes between the two study periods revealed a significant lower risk for newborns large for gestational age (LGA) (0.93 (0.91-0.95)), pre-term delivery (0.94 (0.92-0.97)) and neonatal hypoglycemia (0.83 (0.77-0.90)) in period 2.

CONCLUSION

The introduction of the IADPSG criteria for the screening of GDM increased prevalence by threefold with no substantial improvements in GDM related events for women without risk factors but reduced the risks for LGA, neonatal hypoglycemia and preterm birth.

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.

What is known and what remains unresolved regarding gestational diabetes mellitus (GDM)

Gestational diabetes mellitus (GDM) has become a major public health issue and one of the most discussed topics in contemporary obstetrics. Due to rising prevalence of GDM worldwide impact and importance of this medical condition in good quality antenatal care is growing. GDM is associated with serious adverse perinatal outcomes and unfavorable long-term health consequences for both, mother and her child. Despite a great amount of knowledge accumulated regarding GDM, medical community remains indecisive and still debates the most appropriate diagnostic strategy, screening policy, and treatment options for pregnancies complicated with GDM. These unresolved issues generate controversies, motivate further research and contribute to the growing interest surrounding GDM. In this review we will discuss and try to explain some of them.

Gestational diabetes mellitus diagnosed at 24 to 28 weeks of gestation in older and obese Women: Is it too late?

Aim/Background

The prevalence of elderly pregnancy and maternal obesity is increasing worldwide. In old and obese women, metabolic derangement affecting fetal growth might be present earlier than the diagnosis of gestational diabetes mellitus (GDM) or even before pregnancy. We thus investigated whether GDM diagnosed at 24–28 weeks of gestation had already affected fetal abdominal growth and, if so, whether elderly pregnancy and/or maternal obesity aggravate fetal abdominal obesity.

Methods

We retrospectively reviewed the medical records of 7820 singleton pregnant women who had been universally screened using a 50-g glucose challenge test (GCT) at 24–28 weeks of gestation, and underwent a 3-h 100-g oral glucose tolerance test (OGTT) if GCT were ≥140mg/dl. GDM and normal glucose tolerance (NGT) were diagnosed using the Carpenter-Coustan criteria. Fetal abdominal obesity was investigated by assessing the fetal abdominal overgrowth ratios (FAORs) of the ultrasonographically estimated gestational age (GA) of abdominal circumference per actual GA by the last menstruation period, biparietal diameter or femur length, respectively. Fetal abdominal overgrowth was defined as FAOR ≥ 90^th percentile. The subjects were divided into four study groups: group 1 (age < 35 years and pre-pregnancy body mass index [BMI] < 25 kg/m²), group 2 (age < 35 years and ≥ 25), group 3 (age ≥ 35 years and BMI < 25), and group 4 (age ≥ 35 years and ≥ 25).

Results

The overall prevalence of GDM was 5.1%, with old and obese group 4 exhibiting the highest prevalence (22.4%). FAORs were significantly higher in the fetus of those with GDM than in the NGT subjects. But, in the subgroup analysis, only old and nonobese group 3 and old and obese group 4 with GDM exhibited significantly higher FAORs than the NGT subjects. Also, risk of fetal abdominal overgrowth was increased in group 3 and 4 subjects with GDM but not in young and nonobese group 1 GDM. The risk of fetal abdominal overgrowth significantly increased with maternal age >35 years, pre-pregnancy BMI >20kg/m², and HbA1c >37.7 mmol/mol (5.6%). In multivariate analyses, maternal age and HbA1c were significantly associated with FAORs.

Conclusion

GDM diagnosed at 24–28 weeks of gestation already affected fetal abdominal obesity in older and/or obese women, but not in younger and nonobese women. Our data suggest that selective screening and appropriate intervention of GDM earlier than 24–28 weeks of gestation might be necessary for high-risk old and/or obese women.

Projections of the prevalence of hyperglycaemia in pregnancy in 2019 and beyond: Results from the International Diabetes Federation Diabetes Atlas, 9th edition

AIM

Hyperglycaemia in pregnancy (HIP) is one of the most common complications of pregnancy. This study aims to examine the projected HIP prevalence in 2030 and 2045 using multiple methods.

METHODS

The International Diabetes Federation Diabetes Atlas 2019 prevalence was projected to 2030 and 2045 by: (1) carrying forward the 2019 age-adjusted prevalence rates; (2) applying a linear regression of the past four editions of the IDF Diabetes Atlas; (3) applying a regression of the previous editions with the most consistent trend, followed by extrapolation from the 9th edition HIP estimate.

RESULTS

Respectively, for 2030 and 2045, Method 1 projected a declining HIP rate with prevalences of 14.0% and 13.3%, Method 2 projected an increasing HIP prevalence at 16.5% and 18.3%, Method 3 predicted stabilisation of the rate from 16.0% to 15.8%.

CONCLUSION

Assuming other factors remain unchanged, our best estimation of age-adjusted HIP will show stabilisation between 2019 and 2045 of 15.8% to 16.0%. However, this estimate is confounded by the heterogeneity of studies and the influence of different gestational diabetes mellitus diagnostic criteria. To provide accurate future comparisons we recommend standardising the diagnostic criteria to the International Association of Diabetes in Pregnancy Study Groups.