Toward universal criteria for gestational diabetes: the 75-gram glucose tolerance test in pregnancy

Impact of the COVID-19 lockdown on the O'Sullivan test and gestational diabetes mellitus diagnosis in pregnant Spanish women

OBJECTIVE

To analyze the impact of COVID-19 lockdown on serum glucose levels of pregnant women.

DESIGN

A retrospective analysis of O'Sullivan test in pregnant women who underwent COVID-19 lockdown compared to controls. SITE: Poniente Primary Health Care center in Córdoba (Spain).

PARTICIPANTS

235 pregnant women from 23+0 to 25+0 weeks of gestation without diabetes mellitus.

INTERVENTIONS

Gestational diabetes mellitus screening with O'Sullivan test and 3-h oral glucose tolerance test.

MAIN MEASUREMENTS

Pregnant women who underwent gestational diabetes mellitus screening with O'Sullivan test before (control group) and during COVID-19 Lockdown (Lockdown group) in Córdoba (Spain) were investigated. Lockdown group was divided in early and late lockdown. An additional, control group from data of the same months of the Lockdown in the previous year were recorded to discarded seasonally (adjusted seasonally control) this group was also divided in early and late seasonally adjusted. A logistic regression model for O'Sullivan test has been performed to analyze potential cofounders. Kolgomorov-Smirnov and Kruskal-Wallis test comparing pregnant women who underwent COVID-19 lockdown with the two types of controls.

RESULTS

Statistically significant differences were found in serum glucose after O'Sullivan test between lockdown group and control group (123.51±26.02mg/dL and 112.86±31.28mg/dL; p=0.017). When early lockdown group and control group were compared no differences were found (119.64±26.18mg/dL vs. 112.86±31.28mg/dL; p>0.05) whereas differences were observed in late lockdown group and control group (127.22±25.59mg/dL vs. 112.86±31.28mg/dL; p=0.009). Statistical trends were also found between lockdown group and seasonally adjusted group and between lockdown and late seasonally adjusted group (p=0.089). A higher proportion of positive O'Suvillan pregnant women who were subsequently diagnosed with GDM were found in lockdown group compared to the seasonally adjusted control group (60% vs. 26.06% respectively; p<0.05).

CONCLUSIONS

The COVID-19 lockdown was associated with an increase in serum glucose levels after the O'Sullivan test as well as a higher GDM diagnosis risk in pregnant women. The findings of our study emphasize the essential requirement for comprehensive maternal services and the accessibility to community's health assets during future lockdown scenarios to pregnant women.

Genetic variants in epoxyeicosatrienoic acid processing and degradation pathways are associated with gestational diabetes mellitus

AIM

To explore the genetic effects of CYP2C8, CYP2C9, CYP2J2, and EPHX2, the key genes involved in epoxyeicosatrienoic acid processing and degradation pathways in gestational diabetes mellitus (GDM) and metabolic traits in Chinese pregnant women.

METHODS

A total of 2548 unrelated pregnant women were included, of which 938 had GDM and 1610 were considered as controls. Common variants were genotyped using the Infinium Asian Screening Array. Association studies of single nucleotide polymorphisms (SNPs) with GDM and related traits were performed using logistic regression and multivariable linear regression analyses. A genetic risk score (GRS) model based on 12 independent target SNPs associated with GDM was constructed. Logistic regression was used to estimate odds ratios and 95% confidence intervals, adjusting for potential confounders including age, pre-pregnancy body mass index, history of polycystic ovarian syndrome, history of GDM, and family history of diabetes, with GRS entered both as a continuous variable and categorized groups. The relationship between GRS and quantitative traits was also evaluated.

RESULTS

The 12 SNPs in CYP2C8, CYP2C9, CYP2J2, and EPHX2 were significantly associated with GDM after adjusting for covariates (all P < 0.05). The GRS generated from these SNPs significantly correlated with GDM. Furthermore, a significant interaction between CYP2J2 and CYP2C8 in GDM (P_Interaction = 0.014, OR_Interaction= 0.61, 95%CI 0.41-0.90) was observed.

CONCLUSION

We found significant associations between GDM susceptibility and 12 SNPs of the four genes involved in epoxyeicosatrienoic acid processing and degradation pathways in a Chinese population. Subjects with a higher GRS showed higher GDM susceptibility with higher fasting plasma glucose and area under the curve of glucose and poorer β-cell function.

Impact of gestational diabetes mellitus treatment on medium/long-term outcomes after pregnancy: A systematic review and meta-analysis

AIM

We aimed to evaluate the effect of gestational diabetes mellitus (GDM) treatment on medium/long-term outcomes both the mother and offspring.

METHODS

We performed a systematic review on randomized clinical trials addressing specific treatment of women with GDM versus usual care and its impact on maternal and offspring outcomes at medium/long-term. MEDLINE, EMBASE and CENTRAL were searched from inception to 8 October 2021.

OUTCOME VARIABLES

maternal (diabetes, metabolic syndrome, 12 secondary); offspring (diabetes, impaired fasting glucose, impaired glucose tolerance, high body mass index, 15 secondary). Risk of bias was assessed with Cochrane tool and aggregation performed with Revman 5.4.

RESULTS

We included five studies (1140 women, 767 offspring) with follow-up ranging 4-16 years after delivery. GDM treatment likely does not reduce risk of maternal diabetes (RR 1.00; [95% CI 0.82-1.23]) and may not reduce that of metabolic syndrome (RR 0.93; [95% CI 0.71-1.22]). We obtained very uncertain evidence that treatment may increase maternal HDL-cholesterol. Findings showed that GDM treatment may not have an impact on infants' outcomes (RRs 0.79; [95% CI 0.39-1.69] for impaired fasting glucose; RR 0.91; [95% CI 0.74-1.12] for body mass index >85th centile and 0.89; [95% CI 0.65-1.22] for body mass index >95th centile respectively).

CONCLUSIONS

With current evidence is uncertain if specific treatment of women with GDM has an impact on medium/long-term metabolic outcomes either in the mother or in the offspring. These results add evidence to the recommendation of systematically reevaluating mother and offspring after delivery.

REGISTRATION

OSF, DOI 10.17605/OSF.IO/KFN79.

Oral glucose tolerance test to diagnose gestational diabetes mellitus: Impact of variations in specimen handling

To improve birth outcomes, all pregnant women without known diabetes are recommended for an oral glucose tolerance test (OGTT) to screen for hyperglycaemia in pregnancy (diabetes in pregnancy or gestational diabetes mellitus (GDM)). This narrative review presents contemporary approaches to minimise preanalytical glycolysis in OGTT samples with a focus on GDM diagnosis using criteria derived from the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study. The challenges of implementing each approach across a diverse Australian healthcare setting were explored. Many Australian sites currently collect and transport OGTT samples at ambient temperature in sodium fluoride (NaF) tubes which is likely to lead to missed diagnosis of GDM in a significant proportion of cases. Alternative preanalytical solutions should be pragmatic and tailored to individual settings and as close as possible to the preanalytical conditions of the HAPO study for correct interpretation of OGTT results. Rapid centrifugation of barrier tubes to separate plasma could be suitable in urban settings provided time to centrifugation is strictly controlled. Tubes containing NaF and citrate could be useful for remote or resource poor settings with long delays to analysis but the impact on the interpretation of OGTT results should be carefully considered. Testing venous blood glucose at the point-of-care bypasses the need for glycolytic inhibition but requires careful selection of devices with robust analytical performance. Studies to evaluate the potential error of each solution compared to the HAPO protocol are required to assess the magnitude of misdiagnosis and inform clinicians regarding the potential impact on patient safety and healthcare costs.

One-step or 2-step testing for gestational diabetes: which is better?

In the United States, the common approach to detecting gestational diabetes mellitus is the 2-step protocol recommended by the American College of Obstetricians and Gynecologists. A 50 g, 1-hour glucose challenge at 24 to 28 weeks' gestation is followed by a 100 g, 3-hour oral glucose tolerance test when a screening test threshold is exceeded. Notably, 2 or more elevated values diagnose gestational diabetes mellitus. The 2-step screening test is administered without regard to the time of the last meal, providing convenience by eliminating the requirement for fasting. However, depending upon the cutoff used and population risk factors, approximately 15% to 20% of screened women require the 100 g, 3-hour oral glucose tolerance test. The International Association of Diabetes and Pregnancy Study Groups recommends a protocol of no screening test but rather a diagnostic 75 g, 2-hour oral glucose tolerance test. One or more values above threshold diagnose gestational diabetes mellitus. The 1-step approach requires that women be fasting for the test but does not require a second visit and lasts 2 hours rather than 3. Primarily because of needing only a single elevated value, the 1-step approach identifies 18% to 20% of pregnant women as having gestational diabetes mellitus, 2 to 3 times the rate with the 2-step procedure, but lower than the current United States prediabetes rate of 24% in reproductive aged women. The resources needed for the increase in gestational diabetes mellitus are parallel to the resources needed for the increased prediabetes and diabetes in the nonpregnant population. A recent randomized controlled trial sought to assess the relative population benefits of the above 2 approaches to gestational diabetes mellitus screening and diagnosis. The investigators concluded that there was no significant difference between the 2-step screening protocol and 1-step diagnostic testing protocol in their impact on population adverse short-term pregnancy outcomes. An accompanying editorial concluded that perinatal benefits of the 1-step approach to diagnosing gestational diabetes mellitus "appear to be insufficient to justify the associated patient and healthcare costs of broadening the diagnosis." We raise several concerns about this conclusion. The investigators posited that a 20% improvement in adverse outcomes among the entire pregnancy cohort would be necessary to demonstrate an advantage to the 1-step approach and estimated the sample size based on that presumption, which we believe to be unlikely given the number of cases that would be identified. In addition, 27% of the women randomized to the 1-step protocol underwent 2-step testing; 6% of the study cohort had no testing at all. A subset of women assigned to 2-step testing did not meet the criteria for gestational diabetes mellitus but were treated as such because of elevated fasting plasma glucose levels, presumably contributing to the reduction in adverse outcomes but not to the number of gestational diabetes mellitus identified, increasing the apparent efficacy of the 2-step approach. No consideration was given to long-term benefits for mothers and offspring. All these factors may have contributed to obscuring the benefits of 1-step testing; most importantly, the study was not powered to identify what we understand to be the likely impact of 1-step testing on population health.

Perinatal Outcomes of Two Screening Strategies for Gestational Diabetes Mellitus: A Randomized Controlled Trial

OBJECTIVE

To evaluate differences in short-term perinatal outcomes between the two prominent screening strategies for gestational diabetes mellitus, the International Association of Diabetes and Pregnancy Study Groups (IADPSG) and Carpenter-Coustan.

METHODS

In this single-site, blinded, randomized, comparative effectiveness trial, participants received a nonfasting 50-g oral glucose tolerance test and, if less than 200 mg/dL (less than 11.1 mmol/L), were randomized to further screening with either IADPSG or Carpenter-Coustan criteria. Gestational diabetes treatment occurred per routine clinical care. The primary outcome was incidence of large-for-gestational-age (LGA) neonates. Prespecified secondary outcomes included small-for-gestational-age (SGA) neonates, cesarean birth, and neonatal and maternal composites of adverse perinatal outcomes. Assuming a 15% incidence of LGA neonates in the Carpenter-Coustan group, 782 participants provided more than 80% power to detect a 7% absolute risk reduction with the use of IADPSG; planned recruitment was 920 for anticipated attrition.

RESULTS

From June 2015 to February 2019, 1,016 participants were enrolled and 921 were randomized to IADPSG (n=461) or Carpenter-Coustan (n=460) groups. Gestational diabetes incidence (14.4% vs 4.5%, P<.001) and diabetes medication use (9.3% vs 2.4%; P<.001) were more common in the IADPSG group; there were no differences in LGA neonates, either overall (risk reduction 0.90, 97.5% CI 0.53-1.52) or among women without gestational diabetes (risk reduction 0.85, 97.5% CI 0.49-1.48). Those screened with IADPSG had higher rates of neonatal morbidity but fewer study-related adverse events. Rates of SGA neonates, cesarean birth, and maternal morbidity composite did not differ significantly between study groups.

CONCLUSIONS

The IADPSG screening criteria resulted in more women diagnosed and treated for gestational diabetes than Carpenter-Coustan without reducing the incidence of LGA birth weight or maternal or neonatal morbidity.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT02309138.

Trends in National Canadian Guideline Recommendations for the Screening and Diagnosis of Gestational Diabetes Mellitus over the Years: A Scoping Review

Canada's largest national obstetric and diabetology organizations have recommended various algorithms for the screening of gestational diabetes mellitus (GDM) over the years. Though uniformity across recommendations from clinical practice guidelines (CPGs) is desirable, historically, national guidelines from Diabetes Canada (DC) and the Society of Obstetricians and Gynaecologists of Canada (SOGC) have differed. Lack of consensus has led to variation in screening approaches, rendering precise ascertainment of GDM prevalence challenging. To highlight the reason and level of disparity in Canada, we conducted a scoping review of CPGs released by DC and the SOGC over the last thirty years and distributed a survey on screening practices among Canadian physicians. Earlier CPGs were based on expert opinion, leading to different recommendations from these organizations. However, as a result of the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study, disparities between DC and the SOGC no longer exist and many Canadian physicians have adopted their recent recommendations. Given that Canadian guidelines now recommend two different screening programs (one step vs. two step), lack of consensus on a single diagnostic threshold continues to exist, resulting in differing estimates of GDM prevalence. Our scoping review highlights these disparities and provides a step forward towards reaching a consensus on one unified threshold.

Glycemic profile of women with normoglycemia and gestational diabetes mellitus during early pregnancy using continuous glucose monitoring system

AIM

We studied women between 8 and 20 weeks of gestation with the aim of evaluating and comparing those having normoglycemia and GDM according to WHO 2013 criteria.

METHODS

In this cross-sectional study (2017-2019), eligible pregnant women underwent a 75-g OGTT, followed by placement of a CGMS.

RESULTS

Women (n = 96, 58 with normoglycemia and 38 with GDM) were enrolled at 14.0 ± 3.2 weeks of gestation. Mean preprandial, 1-h and 2-h postprandial and peak glucose values were significantly higher in women with GDM. Peak glucose value was achieved 60.0 ± 12.3 and 64.3 ± 11.6 min after meal in the normoglycemia and GDM group, respectively. 24-h mean glucose (5.8 ± 0.6 vs. 5.3 ± 0.4 mmol/L), mean daytime glucose (6.0 ± 0.6 vs. 5.5 ± 0.4 mmol/L) and mean nocturnal glucose (5.4 ± 0.7 vs. 5.0 0 ± 0.5 mmol/L) were significantly higher in women with GDM. Total time spent in range was significantly lower in the GDM group compared to the normoglycemia group (92.1 vs. 98.2%).

CONCLUSIONS

This study highlights differences in glycemic patterns between women with normoglycemia and GDM in the context of a South Asian population where burden of GDM is high but good quality data in early pregnancy are limited.

The influence of gestational diabetes mellitus (GDM) and gestational hypertension (GH) on placental morphological changes

Gestational diabetes mellitus (GDM) and gestational hypertension (GH) are some of the most common medical conditions associated with pregnancy. These can be correlated with placental morphopathological changes and implicitly can influence good fetal development. The age and weight of the mother can be correlated directly proportionally with those of the fetus but also with histoarchitecture and placental vascularization. The placental appearance associated with GDM and GH reveals macroscopic features, such as calcifications, fibrin deposits and placental infarcts, but the most relevant pathological features are the microscopic ones, highlighted by the classical staining techniques: Hematoxylin-Eosin (HE), Periodic Acid-Schiff (PAS)-Hematoxylin and Masson's trichrome (MT), but also by immunohistochemical technique with the help of the anti-cluster of differentiation 34 (CD34) antibody that labeled the capital endothelium in the structure of the placental terminal villi and thus we were able to quantify the vascular density according to the associated medical pathology. The microscopic changes identified were represented by intravillous and extravillous fibrin depositions, massive placental infarctions caused by vascular suppression due to various causes, such as thrombosis, but also placental calcifications. All these macroscopic and microscopic morphopathological changes, together with the clinical data of the mother and the newborn, we have demonstrated that they are interconnected and that they can vary depending on the pathology, GH or GDM.

Real-World Gestational Diabetes Screening: Problems with the Oral Glucose Tolerance Test in Rural and Remote Australia

Gestational diabetes mellitus (GDM) is the most common antenatal complication in Australia. All pregnant women are recommended for screening by 75 g oral glucose tolerance test (OGTT). As part of a study to improve screening, 694 women from 27 regional, rural and remote clinics were recruited from 2015–2018 into the Optimisation of Rural Clinical and Haematological Indicators for Diabetes in pregnancy (ORCHID) study. Most routine OGTT samples were analysed more than four hours post fasting collection (median 5.0 h, range 2.3 to 124 h), potentially reducing glucose levels due to glycolysis. In 2019, to assess pre-analytical plasma glucose (PG) instability over time, we evaluated alternative sample handling protocols in a sample of participants. Four extra samples were collected alongside routine room temperature (RT) fluoride-oxalate samples (FLOX^RT): study FLOX^RT; ice slurry (FLOX^ICE); RT fluoride-citrate-EDTA (FC Mix), and RT lithium-heparin plasma separation tubes (PST). Time course glucose measurements were then used to estimate glycolysis from ORCHID participants who completed routine OGTT after 24 weeks gestation (n = 501). Adjusting for glycolysis using FLOX^ICE measurements estimated 62% under-diagnosis of GDM (FLOX^RT 10.8% v FLOX^ICE 28.5% (95% CI, 20.8–29.5%), p < 0.001). FC Mix tubes provided excellent glucose stability but gave slightly higher results (Fasting PG: +0.20 ± 0.05 mmol/L). While providing a realistic alternative to the impractical FLOX^ICE protocol, direct substitution of FC Mix tubes in clinical practice may require revision of GDM diagnostic thresholds.

Gestational diabetes mellitus

Hyperglycaemia that develops during pregnancy and resolves after birth has been recognized for over 50 years, but uniform worldwide consensus is lacking about threshold hyperglycaemic levels that merit a diagnosis of 'gestational diabetes mellitus' (GDM) and thus treatment during pregnancy. GDM is currently the most common medical complication of pregnancy, and prevalence of undiagnosed hyperglycaemia and even overt diabetes in young women is increasing. Maternal overweight and obesity, later age at childbearing, previous history of GDM, family history of type 2 diabetes mellitus and ethnicity are major GDM risk factors. Diagnosis is usually performed using an oral glucose tolerance test (OGTT), although a non-fasting, glucose challenge test (GCT) is used in some parts of the world to screen women for those requiring a full OGTT. Dietary modification and increased physical activity are the primary treatments for GDM, but pharmacotherapy, usually insulin, is used when normoglycaemia is not achieved. Oral hypoglycaemic agents, principally metformin and glibenclamide (glyburide), are also used in some countries. Treatment improves immediate pregnancy outcomes, reducing excess fetal growth and adiposity and pregnancy-related hypertensive disorders. GDM increases the risk of long-term complications, including obesity, impaired glucose metabolism and cardiovascular disease, in both the mother and infant. Optimal management of mother and infant during long-term follow-up remains challenging, with very limited implementation of preventive strategies in most parts of the world.

Gestational Diabetes: Diagnosis, Classification, and Clinical Care

Gestational diabetes mellitus (GDM) affects approximately 6% of pregnant women, and prevalence is increasing in parallel with the obesity epidemic. Protocols for screening/diagnosing GDM are controversial with several guidelines available. Treatment of GDM results in a reduction in the incidence of preeclampsia, shoulder dystocia, and macrosomia. If diet and lifestyle changes do not result in target glucose levels, then treatment with metformin, glyburide, or insulin should begin. It is generally recommended that pregnancies complicated by GDM do not go beyond term. For women identified to have prediabetes, intensive lifestyle intervention and metformin have been shown to prevent or delay progression to type 2 diabetes.

Impact of new International Association of Diabetes and Pregnancy Study Groups (IADPSG) diagnostic criteria on perinatal outcomes in a regional tertiary hospital in New South Wales, Australia

AIMS

We compared the impact of new gestational diabetes (GDM) diagnostic criteria by IADPSG with previous criteria to ascertain concordance between the two criteria; and whether women discordant for GDM between the old and new criteria had increased pregnancy complications.

METHODS

Oral glucose tolerance tests of pregnant women across time periods using old criteria and new criteria were collected. Maternal data and perinatal outcomes were compared between diagnostic concordant and discordant women.

RESULTS

In total, 666/5178 (12.9%) women were diagnosed and treated for GDM. There was a significant increase in odds of any complication in concordant positive women (OR 3.91 95%CI 2.71-5.63, p<.0001); in women only positive by new GDM criteria (OR 2.06, 95% CI 1.41-2.99, p=.0002); and women only positive by old GDM criteria (OR 2.28, 95% CI 1.42-3.66, p=.0006); compared to concordant negative women. This is mainly due to macrosomia and nursery admissions.

CONCLUSION

This study confirms that women diagnosed with GDM on both old and new criteria have a higher rate of birth complications than women without GDM. Women who have been missed out due to new criteria may still be at risk. Therefore, combination of both old and new criteria may be optimal for identifying high-risk pregnancies.

A Simple Index for Detection of Gestational Diabetes Mellitus

The conventional screening test for gestational diabetes mellitus is measurement of plasma glucose 1 hour after 50 g glucose by mouth. The sensitivity and specificity of this test are lower than desirable; we therefore developed an index including other plasma constituents. In a preliminary study, 138 pregnant women had the standard oral glucose load screening test, and plasma fructosamine and total proteins were measured, in addition to glucose, in the 1-hour samples. An index value (I) was calculated as [fructosamine (μmol/L)÷total proteins (g/L)]×[glucose (mmol/L)÷100]. Cut-off values for I were then assessed in a second prospective study, of 642 pregnant women. Definitive diagnosis of gestational diabetes was by oral glucose tolerance test (OGTT). The index was also assessed in terms of fetal macrosomia (birthweight ≥ 4000 g).

With a cut-off value of I=27.2, sensitivity was 98%, specificity 89%, diagnostic efficiency 90%, positive likelihood ratio 8.76. Application of the index would have avoided 42% of the OGTTs demanded by the standard screening test, reducing false positives from about 24% to 10%. Predictive efficacy for macrosomia was 10.3% versus 7.9%.

Our index offers an efficient screening test for gestational diabetes, and with more stringent cut-off points may be applicable as a single-step diagnostic procedure.

Prenatal, Obstetric and Perinatal Aspects in Pregnancy Associated with Pregestational Diabetes

ABSTRACT: We report the case of a 37-year old primigesta, primipara (IGIP) patient with a singleton, naturally obtained pregnancy, diagnosed with type I diabetes mellitus from the age of three, carrier of an insulin pump for 11 years. The patient was diagnosed in adolescence with with a tumor of the ischio-rectal fossa with multiple attempts of excision which failed due to the particular situation of the tumor. Ultrasound examination diagnosed in the first trimester of pregnancy a voluminous right ovarian cystic tumor. The patient presented pregnancy-induced hypertension starting with 28 gestational weeks. Maternal-fetal and obstetric management assumed sequential ultrasound examination, ovarian tumor and maternal blood pressure drug control, and also the surgical management of the ischio-rectal tumor. Cesarean section was performed at 38 gestational weeks, outcoming with a live fetus, normal weight, good neonatal progression and favorable postoperative progression of the mother. In this case report, we emphasize the fact that in pregestational diabetes mellitus and pregnancy-induced hypertension, constant glycemic control, performed by the insulin pump, prior and during gestation, and the maternal blood pressure control are essential for maternal-fetal outcome.

Application of One-Step IADPSG Versus Two-Step Diagnostic Criteria for Gestational Diabetes in the Real World: Impact on Health Services, Clinical Care, and Outcomes

PURPOSE OF REVIEW

This paper seeks to summarize the impact of the one-step International Association of Diabetes and Pregnancy Study Groups (IADPSG) versus the two-step gestational diabetes mellitus (GDM) criteria with regard to prevalence, outcomes, healthcare delivery, and long-term maternal metabolic risk.

RECENT FINDINGS

Studies demonstrate a 1.03-3.78-fold rise in the prevalence of GDM with IADPSG criteria versus baseline criteria. Women with GDM by IADPSG criteria have more adverse pregnancy outcomes than women with normal glucose tolerance (NGT). Treatment of GDM by IADPSG criteria may be cost effective. Use of the fasting glucose as a screen before the 75-g oral glucose tolerance test to rule out GDM with fasting plasma glucose (FPG) < 4.4 (80 mg/dl) and rule in GDM with FPG ≥ 5.1 mmol/l (92 mg/dl) reduces the need for OGTT by 50% and its cost and inconvenience. The prevalence of postpartum abnormal glucose metabolism is higher for women with GDM diagnosed by IADPSG criteria versus that for women with NGT. Data support the use of IADPSG criteria, if the cost of diagnosis and treatment can be controlled and if lifestyle can be optimized to reduce the risk of future diabetes.

Population-Level Outcomes with a 2-Step Approach for Gestational Diabetes Screening and Diagnosis

OBJECTIVES

To examine outcomes associated with alternative glucose thresholds in a 2-step approach for screening and diagnosing gestational diabetes mellitus (GDM).

METHODS

We studied 178,527 pregnancies between 2008 and 2012 in Alberta, Canada. They were categorized retrospectively as normal 50 g screen (n=144,191); normal 75 g oral glucose tolerance test (OGTT) (n=21,248); abnormal at glucose thresholds suggested by the International Association of Diabetes and Pregnancy Group (IADPSG) (HAPO 1.75, n=4308); abnormal at glucose thresholds associated with an odds ratio of 2.0 for adverse events in the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study. This latter group, which would have been treated for GDM based on customary care, was further divided into those with 1 (HAPO 2-1 n=5528) or 2 or more abnormal glucose values (HAPO 2-2 n=3252). Main outcomes were large for gestational age (LGA), induced labour and Cesarean-section rates.

RESULTS

LGA rates were 8.2%, 10.5%, 14.2%, 11.8% and 16.5% among normal 50 g, normal 75 g OGTT, HAPO 1.75, HAPO 2-1, and HAPO 2-2 groups, respectively. Labour induction and caesarean-section rates were 29.6% and 36.2% in the IADPSG, 38.2% and 36.8% in the HAPO 2-1 group, and 42.3% and 41.1% in the HAPO 2-2 groups, respectively. Excessive maternal weight (≥91 kg) was associated with a higher risk for all adverse outcomes.

CONCLUSIONS

The 2-step approach effectively identifies pregnancies at low risk for adverse outcomes. Labelling influences induction practice. Any glucose intolerance increases risk for adverse outcomes, and pregnancies with highest (2 or higher) abnormal glucose values remain at greatest risk. Further research is needed to determine whether glycemic thresholds for GDM diagnosis should incorporate information about maternal weight.

What we have learned about treating mild gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is associated with adverse perinatal outcomes, with risks not only associated with more severe forms of GDM, but milder forms of GDM as well. Treatment of mild GDM with dietary intervention and insulin when necessary has proven to be effective in reducing the risks of several, but not all, adverse perinatal outcomes. Less is known about the long-term benefits of mild GDM treatment. This article will review the benefits of mild GDM treatment, and related risk factors, on short-term and long-term maternal and neonatal/child outcomes, with an emphasis on research conducted by the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network.

Are There Benefits for Gestational Diabetes Mellitus in Treating Lower Levels of Hyperglycemia Than Standard Recommendations?

OBJECTIVES

The new International Association of Diabetes and Pregnancy Study Groups (IADPSG) recommendations for diagnosis of gestational diabetes mellitus (GDM) are generating discussion regarding their universal adoption. Our centre is currently using stricter GDM diagnostic criteria than those proposed by the IADPSG. Evaluation of complication rates and their predictors in our cohort may provide insight for the care of this high-risk population. Therefore, we determined complication rates and identified antepartum maternal predictors of adverse outcomes in our cohort with mild GDM.

METHODS

A retrospective cohort study was performed between 2005 and 2011. It included women with and without GDM, which was diagnosed if fasting plasma glucose levels were 5.0 or above or 2-hour post 75 gram oral glucose tolerance test (OGTT) were 7.8 mmol/L or higher.

RESULTS

A total of 3712 women, with and without diabetes, were included. Rates of macrosomia and pre-eclampsia were significantly higher in the group with GDM but were lower than the rates usually reported. Macrosomia, the need for insulin therapy or caesarean section and postpartum glucose intolerance predictors included prepregnancy body mass index, excessive gestational weight gain and OGTT screening results, although no specific threshold was found.

CONCLUSIONS

This study provides insight into GDM-related complications rates and the benefits of intervention in a large cohort of women with levels of hyperglycemia lower than those currently recommended for diagnosis of GDM. These findings suggest a continuous association between adverse outcomes and maternal hyperglycemia and highlight the important role of maternal risk factors other than glycemic results in the development of pregnancy-related complications. Milder forms of hyperglycemia that would not be identified by IADPSG guidelines may benefit from treatment.

Comparison of maternal and fetal outcomes among Asian Indian pregnant women with or without gestational diabetes mellitus: A situational analysis study (WINGS-3)

AIM

To compare the existing maternal and fetal outcomes in Asian Indian women with or without gestational diabetes mellitus (GDM) before the development of the Women in India with GDM Strategy (WINGS) GDM model of care (MOC).

MATERIALS AND METHODS

Records of pregnant women were extracted retrospectively from three maternity centers in Chennai. GDM was diagnosed using the International Association for Pregnancy Study Groups criteria or the Carpenter and Coustan criteria. Demographic details, obstetric history, antenatal follow-up, treatment for GDM, and outcomes of delivery were collected from the electronic medical records.

RESULTS

Of the 3642 records analyzed, 799 (21.9%) had GDM, of whom 456 (57.1%) were treated with insulin and medical nutrition therapy (MNT), 339 (42.4%) with MNT alone, and 4 (0.5%) with metformin. Women with GDM were older than those without (28.5 ± 4.5 vs. 27.1 ± 4.5 years; P < 0.001) and had higher mean body mass index at first booking (26.4 ± 5.2 kg/m(2) vs. 25.2 ± 5.1 kg/m(2); P < 0.001). Rates of cesarean section (26.2% vs. 18.7%; P < 0.001), preeclampsia (1.8% vs. 0.8%; P = 0.04), and macrosomia (13.9% vs. 10.8%; P = 0.02) were significantly higher among women with GDM. In women with GDM treated with insulin and MNT, emergency cesarean section (16.2% vs. 36.6%; P < 0.0001), preeclampsia (0.7% vs. 3.2%; P = 0.015), and macrosomia (9.9% vs. 18.6%; P = 0.0006) were significantly lesser compared to those treated with MNT alone.

CONCLUSION

Pregnancy outcomes were in general worse in GDM women. Treatment with insulin was associated with a significantly lower risk of complications. However, in countries with limited access to insulin and other medicines may lead to poor follow-up and management of GDM. Data from this retrospective study will form the basis for the development of the WINGS GDM MOC, which will address these gaps in GDM care in low-resource settings.

Gestational diabetes: Glycaemic predictors for fetal macrosomia and maternal risk of future diabetes

AIMS

To investigate how glucose levels at diagnosis of gestational diabetes (GDM) are associated with infant birth weight and long-term risk of manifest diabetes mellitus in the mother.

METHODS

In a case control study GDM pregnancies (n=2085) were compared with non-GDM pregnancies matched for day of delivery and obstetric unit (n=3792). GDM was defined as capillary blood glucose (cB-glucose) ≥9.0mmol/l (plasma glucose ≥10.0mmol/l) after a 75g oral glucose tolerance test (OGTT). The GDM cohort were followed up 8.5-13.5yrs after initial diagnosis with a questionnaire, answered by 1324 GDM women (65%).

RESULTS

GDM women had higher mean infant birth-weight compared with controls (3682g vs. 3541g, P<0.001). In multiple linear regression analysis, birth weight was positively correlated to fasting cB-glucose at GDM diagnosis (P<0.001), increased week of gestation (P<0.001) and BMI before pregnancy (P<0.003), while 2h OGTT cB-glucose values ≥9.0mmol/l were not related. Infants born to mothers with fasting cB-glucose ≤4.5mmol/l had no increased mean birth-weight or macrosomia (≥4500g) compared to controls. In the follow up 334/1324 women (25%) of the GDM women had developed diabetes, 215 type 2 diabetes, 46 type 1 diabetes and 72 unclassified diabetes. In logistic regression fasting cB-glucose and 2h OGTT cB-glucose at diagnosis of GDM as well as BMI >25 and origin outside Europe were risk factors for manifest diabetes.

CONCLUSIONS

Fasting blood glucose at diagnosis of GDM gives important information besides 2h OGTT glucose about pregnancy outcome and future risk for maternal diabetes.

GESTATIONAL DIABETES. OBSTETRICAL PERSPECTIVE

This review discusses current international recommendations for GDM diagnosis and management and argues whether it would be worth considering first, universal screening for GDM in our country, second, updating of management guidelines and third, organized follow-up of women diagnosed with GDM and adoption of lifestyle interventions after delivery that could reduce the onset and prevalence of type 2 DM.

Comparison of the effects of gestational weight gain on pregnancy outcomes between non-diabetic and diabetic women

OBJECTIVE

Appropriate gestational weight gain (GWG) is important in diabetic women. Current GWG guideline is for US general population, but not specific for diabetic women. We compared the effect of GWG on perinatal outcomes between diabetic and non-diabetic women.

METHODS

Fifty two hundred and twelve women who delivered live singleton infants at Korea University Medical Center from January 2009 to December 2013 were included. One hundred twenty-nine overt diabetes women and 322 gestational diabetes women were categorized as diabetic women, and the others were categorized as none-diabetic women. 5,212 women were categorized by GWG (low 1,081; adequate 2,102; or high 2,029; according to the 2009 Institute of Medicine guidelines), and each of the 3 GWG groups was categorized into 2 groups; diabetic or non-diabetic women. And then, we compared perinatal outcomes between diabetic and non-diabetic groups.

RESULTS

In each 3 GWG groups, primary cesarean section delivery, high birth weight, and large for gestational age rates were significantly higher in diabetic women than non-diabetic women. Only in adequate GWG group, preterm birth rate was significantly higher in diabetic women than non-diabetic women.

CONCLUSION

Our study shows that diabetic women had higher rates of adverse perinatal outcomes than non-diabetic women, although they achieved same GWG. It suggests that current GWG guideline may not be adequate for diabetic women, and that diabetic women may need more strict GWG control than normal population.

Odds, risks and appropriate diagnosis of gestational diabetes

The International Association of the Diabetes and Pregnancy Study Groups (IADPSG) diagnostic process and criteria for gestational diabetes mellitus (GDM) have been recommended by the World Health Organization for adoption and were widely introduced into clinical practice in Australia from January 2015 - in Queensland, the Australian Capital Territory and variably across other states. The IADPSG criteria identify women at increased risk of a range of adverse pregnancy outcomes related to maternal hyperglycaemia. The relationship between maternal hyperglycaemia and adverse outcomes is continuous; however, one elevated glucose value is sufficient to impart a higher risk of pregnancy complications. We outline the background and statistical foundations of the IADPSG approach and refute the inference that invalid statistical reasoning underlies the IADPSG approach. The prevalence of GDM diagnosed by IADPSG criteria may be higher or lower than with other criteria, depending on the underlying population prevalence of fasting and post-glucose load hyperglycaemia, which in turn vary with ethnicity. Studies comparing previous Australian criteria to the IADPSG criteria suggest GDM prevalence may decrease or may increase by up to 35% in specific populations with the planned change in criteria. Pregnancy complications have multiple potential underlying causes. No set of glucose criteria will ever be able to fully separate women and babies at risk of pregnancy complications from those who are not.

Diagnosis of GDM: a suggested consensus

Despite recent attempts at building consensus, an internationally consistent definition of gestational diabetes mellitus (GDM) remains elusive. Within and between countries, there is disagreement between obstetric, medical, and endocrine groups as to the diagnosis and management of GDM. The current article aims to discuss the background to the controversy of GDM diagnosis and to address issues related to the detection and treatment of GDM in low-, middle-, and high-resource settings. The criteria recommended by the International Association of the Diabetes and Pregnancy Study Groups (IADPSG), the American Diabetes Association (ADA), and the World Health Organization (WHO) are endorsed. We also wish to put into perspective the importance of GDM, both during and after pregnancy, in terms of its relationship to overall women's health.

Counterpoint: Establishing consensus in the diagnosis of GDM following the HAPO study

The International Association of Diabetes in Pregnancy Study Groups (IADPSG) recommended a new protocol of 1-step testing with a 75 g oral glucose tolerance test for gestational diabetes in 2010. Since that time, these recommendations have been carefully scrutinized and accepted by a variety of organizations, but challenged or rejected by others. In the current review, we present more details regarding the background to the development of the IADPSG recommendations and seek to place them in context with the available epidemiologic and randomized controlled trial data. In this "counterpoint," we also provide specific rebuttal for errors of fact and disputed contentions provided by Long and Cundy in their 2013 article in Current Diabetes Reports.

Diagnostic thresholds for gestational diabetes and their impact on pregnancy outcomes: a systematic review

AIMS

To assess different diagnostic thresholds for gestational diabetes on outcomes for mothers and their offspring in the absence of treatment for gestational diabetes. This information was used to inform a National Institutes of Health consensus conference on diagnosing gestational diabetes.

METHODS

We searched 15 electronic databases from 1995 to May 2012. Study selection was conducted independently by two reviewers. Randomized controlled trials or cohort studies were eligible if they involved women without known pre-existing diabetes mellitus and who did not undergo treatment for gestational diabetes. One reviewer extracted, and a second reviewer verified, data for accuracy. Two reviewers independently assessed methodological quality.

RESULTS

Thirty-eight studies were included. Three large, methodologically strong studies showed a continuous positive relationship between increasing glucose levels and the incidence of Caesarean section and macrosomia. When data were examined categorically (i.e. women meeting or not meeting specific diagnostic thresholds), women with gestational diabetes across all glucose criteria had significantly more Caesarean sections, shoulder dystocia, macrosomia (except for International Association of Diabetes in Pregnancy Study Groups' criteria) and large for gestational age. Higher glucose thresholds did not consistently demonstrate greater risk for all outcomes.

CONCLUSIONS

Higher glucose thresholds did not consistently demonstrate greater risk, possibly because studies did not compare mutually exclusive groups of women. A pragmatic approach for diagnosis of gestational diabetes using Hyperglycemia and Adverse Pregnancy Outcome Study odds ratio 2.0 thresholds warrants further consideration until additional analysis of the data comparing mutually exclusive groups of women is provided and large randomized controlled trials investigating different diagnostic and treatment thresholds are completed.

Response to fifty grams oral glucose challenge test and pattern of preceding fasting plasma glucose in normal pregnant Nigerians

BACKGROUND

Diabetes mellitus in pregnancy has profound implications for the baby and mother and thus active screening for this is desirable.

METHOD

Fifty grams oral glucose challenge test was administered after obtaining consent to 222 women in good health with singleton pregnancies without diabetes mellitus at 24 to 28 weeks gestation after an overnight fast. Venous blood sample was obtained before and 1 hour after the glucose load. A diagnostic 3-hour 100 g oral glucose tolerance test was subsequently performed in all.

RESULTS

Two hundred and ten women had a normal response to oral glucose tolerance test i.e. venous plasma glucose below these cut-off levels: fasting 95 mg/dl (5.3 mmol/l), 1 hour 180 mg/dl (10.0 mmol/l), 2 hours 155 mg/dl (8.6 mmol/l) and 3 hours 140 mg/dl (7.8 mmol/l), while 12 were found to have gestational diabetes mellitus and were subsequently excluded from the study. They were appropriately managed. The mean maternal age was 30.9 ± 4.1 years (range 19 to 45 years) and the mean parity was 1.2 ± 1.1 (range 0 to 5). The mean fasting plasma glucose was 74.5 ± 11.5 mg/dl (range 42 to 117 mg/dl), while the mean plasma glucose 1 hour after 50 g glucose challenge test was 115.3 ± 19.1 mg/dl (range 56 to 180 mg/dl).

CONCLUSIONS

The mean fasting plasma glucose in normal pregnant Nigerians was 74.5 ± 11.5 mg/dl (range 42 to 117 mg/dl). There is a need to re-appraise and possibly review downwards the World Health Organization fasting plasma glucose diagnostic criteria in pregnant Nigerians for better detection of gestational diabetes mellitus. Pregnant women with venous plasma glucose greater than 153.5 mg/dl (8.5 mmol/l) 1 hour after 50 g glucose challenge test are strongly recommended for diagnostic test of gestational diabetes mellitus.

Diabetes and pregnancy: an endocrine society clinical practice guideline

OBJECTIVE

Our objective was to formulate a clinical practice guideline for the management of the pregnant woman with diabetes.

PARTICIPANTS

The Task Force was composed of a chair, selected by the Clinical Guidelines Subcommittee of The Endocrine Society, 5 additional experts, a methodologist, and a medical writer.

EVIDENCE

This evidence-based guideline was developed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to describe both the strength of recommendations and the quality of evidence.

CONSENSUS PROCESS

One group meeting, several conference calls, and innumerable e-mail communications enabled consensus for all recommendations save one with a majority decision being employed for this single exception.

CONCLUSIONS

Using an evidence-based approach, this Diabetes and Pregnancy Clinical Practice Guideline addresses important clinical issues in the contemporary management of women with type 1 or type 2 diabetes preconceptionally, during pregnancy, and in the postpartum setting and in the diagnosis and management of women with gestational diabetes during and after pregnancy.

2-Hour postload serum glucose levels and maternal blood pressure as independent predictors of birth weight in "appropriate for gestational age" neonates in healthy nondiabetic pregnancies

INTRODUCTION

Increased neonatal birth weight (NBW), often associated with diabetic pregnancies, is a recognized indicator of childhood obesity and future metabolic risk. Predictors of NBW in healthy non-diabetic pregnancies are not yet established. Here, we investigated the association of maternal parameters of healthy non-diabetic mothers with NBW of their "appropriate-for-gestational age" neonates.

METHODS

The study involved 36 healthy mother/infant pairs. Examined parameters included NBW, maternal age, first and last trimester (BMI), weight gain, fasting serum lipids and glucose, 2-hour postload glucose levels and blood pressure.

RESULTS

Postload-glucose levels were significantly higher in mothers of heavier neonates. ANOVA results indicated that 15% increase in postload-glucose levels corresponded to more than 0.5 Kg increase in NBW in the third tertile. NBW correlated positively with postload glucose levels, and negatively with systolic blood pressure. Regression analysis showed that the main predictors of NBW were postload-glucose levels (B = 0.455, P = 0.003), followed by systolic blood pressure (B = -0.447, P = 0.004), together predicting 31.7% NBW variation.

CONCLUSION

This study highlights that increased maternal postload sugar levels and blood pressure, within the normal range, highly predicts NBW of healthy mothers. These findings may provide focus for early dietary intervention measures to avoid future risks to the mother and baby.

The relative contribution of prepregnancy overweight and obesity, gestational weight gain, and IADPSG-defined gestational diabetes mellitus to fetal overgrowth

OBJECTIVE

The International Association of Diabetes in Pregnancy Study Groups (IADPSG) criteria for diagnosis of gestational diabetes mellitus (GDM) identifies women and infants at risk for adverse outcomes, which are also strongly associated with maternal overweight, obesity, and excess gestational weight gain.

RESEARCH DESIGN AND METHODS

We conducted a retrospective study of 9,835 women who delivered at ≥20 weeks' gestation; had a prenatal, 2-h, 75-g oral glucose tolerance test; and were not treated with diet, exercise, or antidiabetic medications during pregnancy. Women were classified as having GDM based on IADPSG criteria and were categorized into six mutually exclusive prepregnancy BMI/GDM groups: normal weight ± GDM, overweight ± GDM, and obese ± GDM.

RESULTS

Overall, 5,851 (59.5%) women were overweight or obese and 1,892 (19.2%) had GDM. Of those with GDM, 1,443 (76.3%) were overweight or obese. The prevalence of large-for-gestational-age (LGA) infants was significantly higher for overweight and obese women without GDM compared with their normal-weight counterparts. Among women without GDM, 21.6% of LGA infants were attributable to maternal overweight and obesity, and the combination of being overweight or obese and having GDM accounted for 23.3% of LGA infants. Increasing gestational weight gain was associated with a higher prevalence of LGA in all groups.

CONCLUSIONS

Prepregnancy overweight and obesity account for a high proportion of LGA, even in the absence of GDM. Interventions that focus on maternal overweight/obesity and gestational weight gain, regardless of GDM status, have the potential to reach far more women at risk for having an LGA infant.

Controversies on how diabetes is diagnosed

PURPOSE OF REVIEW

To evaluate the controversial aspects of diabetes diagnosis.

RECENT FINDINGS

Within the past 2 years, revised guidelines for the diagnosis of diabetes have been issued which endorse the use of the hemoglobin A1C as a diagnostic test, in addition to the previously recommended tests. Updated diagnostic criteria for gestational diabetes were also published in the same period. Recent publications on the current role of oral glucose tolerance tests and diagnosis of diabetes in the acutely ill are sparse. There are new recommendations regarding the use of genetic testing and antibody testing in establishing the cause of diabetes.

SUMMARY

The inclusion of A1C as a diagnostic test has many advantages including reproducibility of the test and convenience, but there are situations where the test is unreliable and it misses many individuals who would have been diagnosed by plasma glucose testing. The diagnostic threshold of 6.5% for the A1C remains controversial. There is still no consensus on the best approach to diagnose gestational diabetes. The role of the oral glucose tolerance test seems to be diminishing. Diagnosis of diabetes in acute illness is aided by A1C testing. Genetic and autoantibody testing in specific situations offer diagnostic and therapeutic utility.

Lesser than diabetes hyperglycemia in pregnancy is related to perinatal mortality: a cohort study in Brazil

BACKGROUND

Gestational diabetes related morbidity increases along the continuum of the glycemic spectrum. Perinatal mortality, as a complication of gestational diabetes, has been little investigated. In early studies, an association was found, but in more recent ones it has not been confirmed. The Brazilian Study of Gestational Diabetes, a cohort of untreated pregnant women enrolled in the early 1990's, offers a unique opportunity to investigate this question. Thus, our objective is to evaluate whether perinatal mortality increases in a continuum across the maternal glycemic spectrum.

METHODS

We prospectively enrolled and followed 4401 pregnant women attending general prenatal care clinics in six Brazilian state capitals, without history of diabetes outside of pregnancy, through to birth, and their offspring through the early neonatal period. Women answered a structured questionnaire and underwent a standardized 2-hour 75-g oral glucose tolerance test (OGTT). Obstetric care was maintained according to local protocols. We obtained antenatal, delivery and neonatal data from hospital records. Odds ratios (OR) were estimated using logistic regression.

RESULTS

We ascertained 97 perinatal deaths (67 fetal and 31 early neonatal). Odds of dying increased according to glucose levels, statistically significantly so only for women delivering at gestational age ≥34 weeks (p < 0.05 for glycemia-gestational age interaction). ORs for a 1 standard deviation difference in glucose, when analyzed continuously, were for fasting 1.47 (95% CI 1.12, 1.92); 1-h 1.55 (95% CI 1.15, 2.07); and 2-h 1.53 (95% CI 1.15, 2.02). The adjusted OR for IADPSG criteria gestational diabetes was 2.21 (95% CI 1.15, 4.27); and for WHO criteria gestational diabetes, 3.10 (95% CI 1.39, 6.88).

CONCLUSIONS

In settings of limited detection and treatment of gestational diabetes mellitus, women across a spectrum of lesser than diabetes hyperglycemia, experienced a continuous rise in perinatal death with increasing levels of glycemia after 34 weeks of pregnancy. Current GDM diagnostic criteria identified this increased risk of mortality.

Gestational diabetes mellitus: Get, set, go From diabetes capital of the world to diabetes care capital of the world

Screening and diagnosis for gestational diabetes mellitus (GDM) as well as interventions for its management evoke considerable controversy. There are different types of screening methods: universal or risk-based, one step or two step. Different thresholds for diagnosis of GDM have been in vogue. Previous definition and diagnostic criteria had no place for diagnosis of overt diabetes in pregnancy. Following Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study and International Association of Diabetes and Pregnancy Study Groups (IADPSG) recommendations, new screening and diagnostic criteria around the world seem to be gaining consensus. The present recommendation given by IADPSG for screening and diagnosis of diabetes mellitus in pregnancy has two discrete phases. The first is detection of women with overt diabetes not previously diagnosed or treated outside of pregnancy. Universal early testing in populations is recommended at the first prenatal visit. The second phase is a 75-g OGTT at 24-28 week gestation in all women not previously found to have overt diabetes or GDM. ACHOIS and MFMU Network trails have proven benefit in treating hyperglycemias less than what is diagnostic for diabetes. DIPSI has shown the alternative way for resource-challenged communities. Efforts from all stake holders with interest in GDM are required to make the diabetes capital of the world into the diabetes care capital of the world.

Maternal outcome of gestational diabetes mellitus

OBJECTIVE

To estimate maternal outcome of treated or untreated gestational diabetes mellitus (GDM).

METHODS

French and English publications were searched using PubMed and the Cochrane library.

RESULTS

The diagnosis of GDM includes a high risk population for preeclampsia and Caesarean sections (EL3). The risks are positively correlated with the level of hyperglycaemia in a linear way (EL2). Intensive treatment of mild GDM compared with routine care reduces the risk of pregnancy-induced hypertension (preeclampsia, gestational hypertension). Moreover, it does not increase the risk of operative vaginal delivery, Caesarean section and postpartum haemorrhage (EL1). Being overweight, obesity and maternal hyperglycaemia are independent risk factors for preeclampsia (EL2). Their association with GDM increases the risk of preeclampsia and Caesarean section compared to diabetic women with a normal body mass index (EL3). The association of several risk factors (such as advanced maternal age, pre-existing chronic hypertension, pre-existing nephropathy, obesity, suboptimal glycaemic control) increases the risk of preeclampsia. In that case, the classic follow-up (blood pressure measurement, proteinuria) should be more frequent than monthly (professional consensus). The risk of Caesarean section is increased by macrosomia, whether suspected prenatally or not, but this increased risk remains whatever the birth weight (EL3). Diagnosis and treatment of GDM do not reduce the risk of severe perineal lesions, operative vaginal delivery and postpartum haemorrhage (EL2). Some psychological symptoms, such as anxiety and alteration of self-perception, can occur upon diagnosis of GDM (EL3). The treatment of GDM appears to reduce the risk of postpartum depression symptoms (EL2).

CONCLUSION

Most of the information published on GDM covers the risks of preeclampsia and Caesarean section; intensive care of GDM reduces these risks. Pregnancy care should be adjusted to the risk factors.

Normal fasting plasma glucose levels during pregnancy: a hospital-based study

OBJECTIVE

Recently, the International Association of Diabetes and Pregnancy Study Groups have suggested new criteria for the diagnosis of gestational diabetes including a fasting glucose level of ≥92 mg/dL. We determined reference levels for normal fasting plasma glucose levels throughout pregnancy and evaluated the new normal cut-off for fasting glucose level.

METHODS

Charts of patients who delivered in our hospital between June 2001 and June 2006 were reviewed. Women with pregestational diabetes, fasting glucose level >105 mg/dL or delivery at <24 weeks were excluded. Fasting glucose levels were assessed in 11 time categories between three months prior and four months postpartum in 7946 women.

RESULTS

Compared to preconception levels, fasting glucose levels decreased by a median of 3 mg/dL in the first trimester (81-78 mg/dL). During the third trimester a slight further glucose reduction was observed (median 76 mg/dL). After delivery fasting glucose levels increased sharply (84 mg/dL in the puerperium and 81 mg/dL by three months postpartum). Throughout pregnancy 5.2-9.0% of pregnant women had a fasting glucose level of ≥92 mg/dL [compared to 8.2% in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study].

CONCLUSION

Fasting glucose levels decrease early in pregnancy with only slight further decrease later on. It seems that the same fasting glucose cut-off can be used throughout pregnancy for the diagnosis of gestational diabetes mellitus.

Pregnancy and Diabetes Management: Advances and Controversies

BACKGROUND

The treatment of diabetes in pregnancy has potentially far-reaching benefits for both pregnant women with diabetes and their children and may provide a cost-effective approach to the prevention of obesity, type 2 diabetes mellitus, and metabolic syndrome. Early and accurate diagnosis of diabetes in pregnancy is necessary for optimizing maternal and fetal outcomes.

CONTENT

Optimal control of diabetes in pregnancy requires achieving normoglycemia at all stages of a woman's pregnancy, including preconception and the postpartum period. In this review we focus on new universal guidelines for the screening and diagnosis of diabetes in pregnancy, including the 75-g oral glucose tolerance test, as well as the controversy surrounding the guidelines. We review the best diagnostic and treatment strategies for the pregestational and intrapartum periods, labor and delivery, and the postpartum period, and discuss management algorithms as well as the safety and efficacy of diabetic medications for use in pregnancy.

SUMMARY

Global guidelines for screening, diagnosis, and classification have been established, and offer the potential to stop the cycle of diabetes and obesity caused by hyperglycemia in pregnancy. Normoglycemia is the goal in all aspects of pregnancy and offers the benefits of decreased short-term and long-term complications of diabetes.

Gestational diabetes: costs and consequences

Important new evidence regarding the relationships of maternal glucose to fetal growth and pregnancy complications have emerged in the last 5 years. Major international efforts are underway to translate this evidence into clinical practice and create international norms for the diagnosis of gestational diabetes. Consideration of the costs and benefits of the screening, diagnosis and treatment of gestational diabetes is complex but likely to be central to this translational programme.

Effect of photobleaching on calibration model development in biological Raman spectroscopy

A major challenge in performing quantitative biological studies using Raman spectroscopy lies in overcoming the influence of the dominant sample fluorescence background. Moreover, the prediction accuracy of a calibration model can be severely compromised by the quenching of the endogenous fluorophores due to the introduction of spurious correlations between analyte concentrations and fluorescence levels. Apparently, functional models can be obtained from such correlated samples, which cannot be used successfully for prospective prediction. This work investigates the deleterious effects of photobleaching on prediction accuracy of implicit calibration algorithms, particularly for transcutaneous glucose detection using Raman spectroscopy. Using numerical simulations and experiments on physical tissue models, we show that the prospective prediction error can be substantially larger when the calibration model is developed on a photobleaching correlated dataset compared to an uncorrelated one. Furthermore, we demonstrate that the application of shifted subtracted Raman spectroscopy (SSRS) reduces the prediction errors obtained with photobleaching correlated calibration datasets compared to those obtained with uncorrelated ones.