Attitudes and practices of healthcare providers regarding gestational diabetes: results of a survey conducted at the 2010 meeting of the International Association of Diabetes in Pregnancy Study Group (IADPSG)

Gestational diabetes mellitus: The optimal time of delivery

Gestational diabetes mellitus (GDM) is a common pregnancy complication strongly associated with poor maternal-fetal outcomes. Its incidence and prevalence have been increasing in recent years. Women with GDM typically give birth through either vaginal delivery or cesarean section, and the maternal-fetal outcomes are related to several factors such as cervical level, fetal lung maturity, the level of glycemic control still present, and the mode of treatment for the condition. We categorized women with GDM based on the latter two factors. GDM that is managed without medication when it is responsive to nutrition- and exercise-based therapy is considered diet- and exercise-controlled GDM, or class A1 GDM, and GDM managed with medication to achieve adequate glycemic control is considered class A2 GDM. The remaining cases in which neither medical nor nutritional treatment can control glucose levels or patients who do not control their blood sugar are categorized as class A3 GDM. We investigated the optimal time of delivery for women with GDM according to the classification of the condition. This review aimed to address the benefits and harms of giving birth at different weeks of gestation for women with different classes of GDM and attempted to provide an analytical framework and clearer advice on the optimal time for labor.

Analysis and Intervention of Factors Affecting Abnormal Postpartum Glucose Tolerance and Gestational Recurrence in Gestational Diabetes

ObjectiveTo investigate the influencing factors of abnormal postpartum glucose tolerance and pregnancy recurrence in gestational diabetes mellitus (GDM) and to develop reasonable interventions to prevent postpartum glucose tolerance and recurrence of pregnancy. Methods. Retrospective analysis of clinical data of 238 GDM patients during pregnancy, including age, body mass index (BMI) before and after pregnancy, regular exercise during pregnancy, insulin use, family history of diabetes, fasting blood glucose (FPG) during pregnancy, oral glucose tolerance test (OGTT) 2 h time value, blood lipid index, and whether pregnant again. At the same time, the women were followed up by telephone or home visits to understand and guide the patient's diet and exercise. The clinical characteristics of the two groups of patients were compared. According to the OGTT test, the recovery of glucose tolerance in pregnant women 6–8 weeks postpartum was divided into the normal postpartum glucose tolerance group and the abnormal group. Logistic multivariate analysis was used to find the influencing factors of postpartum glucose tolerance and recurrence of pregnancy. Results. Between 238 patients of followed-up, 150 pregnant women had abnormal postpartum glucose tolerance, accounting for 63.03%. There were 115 repregnants, of whom 37 (32.17%) had a recurrence of postpartum glucose tolerance. Pre and postpregnancy BMI, insulin use during pregnancy, family history of diabetes, FPG during pregnancy, OGTT 2 h values, and triglyceride (TG) were independent risk factors for abnormal postpartum diabetes and recurrence of pregnancy in GDM patients. Conclusions. Patients with GDM are at high risk of postpartum abnormal glucose tolerance and pregnancy recurrence, which may be influenced by the pregnant woman's prepregnancy and postpartum BMI, insulin use during pregnancy, family history of diabetes, FPG, OGGT 2 h values during pregnancy, and TG levels. Therefore, health education for pregnant women should be strengthened in the clinic, with guidance on proper diet for weight control, increased exercise, and regular blood glucose screening and monitoring for those at risk.

Provider-based initiation and management of pharmacologic therapy for gestational diabetes mellitus

OBJECTIVE

After failure of diet and exercise prescribed for gestational diabetes mellitus (GDM), pharmacotherapy initiation is recommended. The objective of this study was to examine the association between provider type and timing of pharmacotherapy initiation.

METHODS

This was a retrospective cohort study of women with a singleton pregnancy and diagnosis of A2GDM (GDM requiring pharmacotherapy) delivering in a tertiary care center between 2009 and 2019. Variables including maternal demographics, GDM characteristics, and provider type (general obstetrician/gynecologists (OBGYN), maternal-fetal medicine (MFM), or endocrinology) were assessed. The percent of abnormal glucose values at pharmacotherapy initiation was compared among provider types via univariable and multivariable analyses.

RESULTS

A total of 428 women were included in the analysis. Eighteen percent were managed by MFM, 54% by general OBGYN, and 28% by endocrinology. Insulin was prescribed in 45.8% of women. In univariable analysis, the percent of abnormal glucose values was higher in women managed by MFMs, compared with general OBGYN and endocrinology (58.0%±25.1, 50.0%±23.1, and 50.3%±26.8, respectively, p = .041). Women started on insulin as first-line pharmacotherapy were more likely to be managed by endocrinology (p < .001). After adjusting for confounding variables, provider type was not significantly associated with percent of abnormal glucose values at pharmacotherapy initiation, but endocrinology was more likely to initiate insulin (aOR = 9.33, 95% CI 4.27-20.39).

CONCLUSIONS

Provider type was not associated with percent of elevated glucose values at the time of pharmacotherapy initiation for A2GDM, but it was associated with insulin usage as first-line pharmacotherapy.

Timing of delivery in women with diabetes: A population-based study

Introduction

Women with diabetes, and their infants, have an increased risk of adverse events due to excess fetal growth. Earlier delivery, when fetuses are smaller, may reduce these risks. This study aimed to evaluate the week‐specific risks of maternal and neonatal morbidity/mortality to assist with obstetrical decision making.

Material and methods

In this population‐based cohort study, women with type 1 diabetes (n = 5889), type 2 diabetes (n = 9422) and gestational diabetes (n = 138 917) and a comparison group without diabetes (n = 2 553 243) who delivered a singleton infant at ≥36 completed weeks of gestation between 2004 and 2014 were identified from the Canadian Institute of Health Information Discharge Abstract Database. Multivariate logistic regression was used to determine the week‐specific rates of severe maternal and neonatal morbidity/mortality among women delivered iatrogenically vs those undergoing expectant management.

Results

For all women, the absolute risk of severe maternal morbidity/mortality was low, typically impacting less than 1% of women, and there was no significant difference in gestational age‐specific severe maternal morbidity/mortality between iatrogenic delivery and expectant management among women with any form of diabetes. Among women with gestational diabetes, iatrogenic delivery was associated with an increased risk of neonatal morbidity/mortality compared with expectant management at 36 and 37 weeks’ gestation (76.7 and 27.8 excess cases per 1000 deliveries, respectively) and a lower risk of neonatal morbidity/mortality at 38, 39 and 40 weeks’ gestation (7.9, 27.3 and 15.9 fewer cases per 1000 deliveries, respectively). Increased risks of severe neonatal morbidity following iatrogenic delivery compared with expectant management were also observed for women with type 1 diabetes at 36 (98.3 excess cases per 1000 deliveries) and 37 weeks’ gestation (44.5 excess cases per 1000 deliveries) and for women with type 2 diabetes at 36 weeks’ gestation (77.9 excess cases per 1000 deliveries) weeks.

Conclusions

The clinical decision regarding timing of delivery is complex and contingent on maternal‐fetal wellbeing, including adequate glycemic control. This study suggests that delivery at 38, 39 or 40 weeks’ gestation may optimize neonatal outcomes among women with diabetes.

Guideline No. 393-Diabetes in Pregnancy

OBJECTIVES

This guideline reviews the evidence relating to the diagnosis and obstetrical management of diabetes in pregnancy.

OUTCOMES

The outcomes evaluated were short and long-term maternal outcomes including pre-eclampsia, Caesarean section, future diabetes and other cardiovascular complications; and fetal outcomes including congenital anomalies, stillbirth, macrosomia, birth trauma, hypoglycemia and long-term effects.

EVIDENCE

Published literature was retrieved through searches of PubMed and The Cochrane Library using appropriate controlled vocabulary (MeSH terms "diabetes" and "pregnancy"). Where appropriate, results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date limits but results were limited to English or French language materials.

VALUES

The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care.

SUMMARY STATEMENTS

RECOMMENDATIONS.

Treatments for women with gestational diabetes mellitus: an overview of Cochrane systematic reviews

BACKGROUND

Successful treatments for gestational diabetes mellitus (GDM) have the potential to improve health outcomes for women with GDM and their babies.

OBJECTIVES

To provide a comprehensive synthesis of evidence from Cochrane systematic reviews of the benefits and harms associated with interventions for treating GDM on women and their babies.

METHODS

We searched the Cochrane Database of Systematic Reviews (5 January 2018) for reviews of treatment/management for women with GDM. Reviews of pregnant women with pre-existing diabetes were excluded.Two overview authors independently assessed reviews for inclusion, quality (AMSTAR; ROBIS), quality of evidence (GRADE), and extracted data.

MAIN RESULTS

We included 14 reviews. Of these, 10 provided relevant high-quality and low-risk of bias data (AMSTAR and ROBIS) from 128 randomised controlled trials (RCTs), 27 comparisons, 17,984 women, 16,305 babies, and 1441 children. Evidence ranged from high- to very low-quality (GRADE). Only one effective intervention was found for treating women with GDM.EffectiveLifestyle versus usual careLifestyle intervention versus usual care probably reduces large-for-gestational age (risk ratio (RR) 0.60, 95% confidence interval (CI) 0.50 to 0.71; 6 RCTs, N = 2994; GRADE moderate-quality).PromisingNo evidence for any outcome for any comparison could be classified to this category.Ineffective or possibly harmful Lifestyle versus usual careLifestyle intervention versus usual care probably increases the risk of induction of labour (IOL) suggesting possible harm (average RR 1.20, 95% CI 0.99 to 1.46; 4 RCTs, N = 2699; GRADE moderate-quality).Exercise versus controlExercise intervention versus control for return to pre-pregnancy weight suggested ineffectiveness (body mass index, BMI) MD 0.11 kg/m², 95% CI -1.04 to 1.26; 3 RCTs, N = 254; GRADE moderate-quality).Insulin versus oral therapyInsulin intervention versus oral therapy probably increases the risk of IOL suggesting possible harm (RR 1.3, 95% CI 0.96 to 1.75; 3 RCTs, N = 348; GRADE moderate-quality).Probably ineffective or harmful interventionsInsulin versus oral therapyFor insulin compared to oral therapy there is probably an increased risk of the hypertensive disorders of pregnancy (RR 1.89, 95% CI 1.14 to 3.12; 4 RCTs, N = 1214; GRADE moderate-quality).InconclusiveLifestyle versus usual careThe evidence for childhood adiposity kg/m² (RR 0.91, 95% CI 0.75 to 1.11; 3 RCTs, N = 767; GRADE moderate-quality) and hypoglycaemia was inconclusive (average RR 0.99, 95% CI 0.65 to 1.52; 6 RCTs, N = 3000; GRADE moderate-quality).Exercise versus controlThe evidence for caesarean section (RR 0.86, 95% CI 0.63 to 1.16; 5 RCTs, N = 316; GRADE moderate quality) and perinatal death or serious morbidity composite was inconclusive (RR 0.56, 95% CI 0.12 to 2.61; 2 RCTs, N = 169; GRADE moderate-quality).Insulin versus oral therapyThe evidence for the following outcomes was inconclusive: pre-eclampsia (RR 1.14, 95% CI 0.86 to 1.52; 10 RCTs, N = 2060), caesarean section (RR 1.03, 95% CI 0.93 to 1.14; 17 RCTs, N = 1988), large-for-gestational age (average RR 1.01, 95% CI 0.76 to 1.35; 13 RCTs, N = 2352), and perinatal death or serious morbidity composite (RR 1.03; 95% CI 0.84 to 1.26; 2 RCTs, N = 760). GRADE assessment was moderate-quality for these outcomes.Insulin versus dietThe evidence for perinatal mortality was inconclusive (RR 0.74, 95% CI 0.41 to 1.33; 4 RCTs, N = 1137; GRADE moderate-quality).Insulin versus insulinThe evidence for insulin aspart versus lispro for risk of caesarean section was inconclusive (RR 1.00, 95% CI 0.91 to 1.09; 3 RCTs, N = 410; GRADE moderate quality).No conclusions possibleNo conclusions were possible for: lifestyle versus usual care (perineal trauma, postnatal depression, neonatal adiposity, number of antenatal visits/admissions); diet versus control (pre-eclampsia, caesarean section); myo-inositol versus placebo (hypoglycaemia); metformin versus glibenclamide (hypertensive disorders of pregnancy, pregnancy-induced hypertension, death or serious morbidity composite, insulin versus oral therapy (development of type 2 diabetes); intensive management versus routine care (IOL, large-for-gestational age); post- versus pre-prandial glucose monitoring (large-for-gestational age). The evidence ranged from moderate-, low- and very low-quality.

AUTHORS' CONCLUSIONS

Currently there is insufficient high-quality evidence about the effects on health outcomes of relevance for women with GDM and their babies for many of the comparisons in this overview comparing treatment interventions for women with GDM. Lifestyle changes (including as a minimum healthy eating, physical activity and self-monitoring of blood sugar levels) was the only intervention that showed possible health improvements for women and their babies. Lifestyle interventions may result in fewer babies being large. Conversely, in terms of harms, lifestyle interventions may also increase the number of inductions. Taking insulin was also associated with an increase in hypertensive disorders, when compared to oral therapy. There was very limited information on long-term health and health services costs. Further high-quality research is needed.

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.

Oral anti-diabetic pharmacological therapies for the treatment of women with gestational diabetes

BACKGROUND

Gestational diabetes mellitus (GDM) is a major public health issue with rates increasing globally. Gestational diabetes, glucose intolerance first recognised during pregnancy, usually resolves after birth and is associated with short- and long-term complications for the mother and her infant. Treatment options can include oral anti-diabetic pharmacological therapies.

OBJECTIVES

To evaluate the effects of oral anti-diabetic pharmacological therapies for treating women with GDM.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register (14 May 2016), ClinicalTrials.gov, WHO ICTRP (14 May 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

We included published and unpublished randomised controlled trials assessing the effects of oral anti-diabetic pharmacological therapies for treating pregnant women with GDM. We included studies comparing oral anti-diabetic pharmacological therapies with 1) placebo/standard care, 2) another oral anti-diabetic pharmacological therapy, 3) combined oral anti-diabetic pharmacological therapies. Trials using insulin as the comparator were excluded as they are the subject of a separate Cochrane systematic review.Women with pre-existing type 1 or type 2 diabetes were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and trial quality. Two review authors independently extracted data and data were checked for accuracy.

MAIN RESULTS

We included 11 studies (19 publications) (1487 women and their babies). Eight studies had data that could be included in meta-analyses. Studies were conducted in Brazil, India, Israel, UK, South Africa and USA. The studies varied in diagnostic criteria and treatment targets for glycaemic control for GDM. The overall risk of bias was 'unclear' due to inadequate reporting of methodology. Using GRADE the quality of the evidence ranged from moderate to very low quality. Evidence was downgraded for risk of bias (reporting bias, lack of blinding), inconsistency, indirectness, imprecision and for oral anti-diabetic therapy versus placebo for generalisability. Oral anti-diabetic pharmacological therapies versus placebo/standard careThere was no evidence of a difference between glibenclamide and placebo groups for hypertensive disorders of pregnancy (risk ratio (RR) 1.24, 95% confidence interval (CI) 0.81 to 1.90; one study, 375 women, very low-quality evidence), birth by caesarean section (RR 1.03, 95% CI 0.79 to 1.34; one study, 375 women, very low-quality evidence), perineal trauma (RR 0.98, 95% CI 0.06 to 15.62; one study, 375 women, very low-quality evidence) or induction of labour (RR 1.18, 95% CI 0.79 to 1.76; one study, 375 women; very low-quality evidence). No data were reported for development of type 2 diabetes or other pre-specified GRADE maternal outcomes (return to pre-pregnancy weight, postnatal depression). For the infant, there was no evidence of a difference in the risk of being born large-for-gestational age (LGA) between infants whose mothers had been treated with glibenclamide and those in the placebo group (RR 0.89, 95% CI 0.51 to 1.58; one study, 375, low-quality evidence). No data were reported for other infant primary or GRADE outcomes (perinatal mortality, death or serious morbidity composite, neurosensory disability in later childhood, neonatal hypoglycaemia, adiposity, diabetes). Metformin versus glibenclamideThere was no evidence of a difference between metformin- and glibenclamide-treated groups for the risk of hypertensive disorders of pregnancy (RR 0.70, 95% CI 0.38 to 1.30; three studies, 508 women, moderate-quality evidence), birth by caesarean section (average RR 1.20, 95% CI 1.20; 95% CI 0.83 to 1.72, four studies, 554 women, I2 = 61%, Tau2 = 0.07 low-quality evidence), induction of labour (0.81, 95% CI 0.61 to 1.07; one study, 159 women; low-quality evidence) or perineal trauma (RR 1.67, 95% CI 0.22 to 12.52; two studies, 158 women; low-quality evidence). No data were reported for development of type 2 diabetes or other pre-specified GRADE maternal outcomes (return to pre-pregnancy weight, postnatal depression). For the infant there was no evidence of a difference between the metformin- and glibenclamide-exposed groups for the risk of being born LGA (average RR 0.67, 95% CI 0.24 to 1.83; two studies, 246 infants, I2 = 54%, Tau2 = 0.30 low-quality evidence). Metformin was associated with a decrease in a death or serious morbidity composite (RR 0.54, 95% CI 0.31 to 0.94; one study, 159 infants, low-quality evidence). There was no clear difference between groups for neonatal hypoglycaemia (RR 0.86, 95% CI 0.42 to 1.77; four studies, 554 infants, low-quality evidence) or perinatal mortality (RR 0.92, 95% CI 0.06 to 14.55, two studies, 359 infants). No data were reported for neurosensory disability in later childhood or for adiposity or diabetes. Glibenclamide versus acarboseThere was no evidence of a difference between glibenclamide and acarbose from one study (43 women) for any of their maternal or infant primary outcomes (caesarean section, RR 0.95, 95% CI 0.53 to 1.70; low-quality evidence; perinatal mortality - no events; low-quality evidence; LGA , RR 2.38, 95% CI 0.54 to 10.46; low-quality evidence). There was no evidence of a difference between glibenclamide and acarbose for neonatal hypoglycaemia (RR 6.33, 95% CI 0.87 to 46.32; low-quality evidence). There were no data reported for other pre-specified GRADE or primary maternal outcomes (hypertensive disorders of pregnancy, development of type 2 diabetes, perineal trauma, return to pre-pregnancy weight, postnatal depression, induction of labour) or neonatal outcomes (death or serious morbidity composite, adiposity or diabetes).

AUTHORS' CONCLUSIONS

There were insufficient data comparing oral anti-diabetic pharmacological therapies with placebo/standard care (lifestyle advice) to inform clinical practice. There was insufficient high-quality evidence to be able to draw any meaningful conclusions as to the benefits of one oral anti-diabetic pharmacological therapy over another due to limited reporting of data for the primary and secondary outcomes in this review. Short- and long-term clinical outcomes for this review were inadequately reported or not reported. Current choice of oral anti-diabetic pharmacological therapy appears to be based on clinical preference, availability and national clinical practice guidelines.The benefits and potential harms of one oral anti-diabetic pharmacological therapy compared with another, or compared with placebo/standard care remains unclear and requires further research. Future trials should attempt to report on the core outcomes suggested in this review, in particular long-term outcomes for the woman and the infant that have been poorly reported to date, women's experiences and cost benefit.

Pharmacokinetics, efficacy and safety of glyburide for treatment of gestational diabetes mellitus

INTRODUCTION

Gestational diabetes mellitus (GDM) complicates 10% of all pregnancies and is defined as hyperglycemia first noted during pregnancy. Rates of GDM are rising and untreated GDM results in complications for both mother and fetus. GDM is often managed by diet and exercise but 30-40% of women will require pharmacological intervention. Insulin has traditionally been the treatment of choice but since 2007, glyburide, a second generation sulfonylurea has become the most prescribed medication for GDM.

AREAS COVERED

This review will cover the pharmacokinetics, efficacy, and safety of glyburide for the management of GDM.

EXPERT OPINION

Management of GDM is challenging secondary to the stringent glycemic goals that mimic the lower glucose levels in pregnancy. Glyburide is generally effective in treating hyperglycemia. However, several studies have raised safety concerns showing higher neonatal intensive care unit (NICU) admissions, higher rates of macrosomia, large for gestational age and pre-eclampsia in the mother. For this reason, insulin should be first-line therapy for GDM. In areas of limited resources where the self-monitoring needed for accurate insulin dosing is not possible, where access to refrigeration for insulin storage is not universal, or severe needle phobia then the benefits of glyburide (controlling hyperglycemia) outweighs the harm of NICU admissions and macrosomia.

Diabetes in Pregnancy

OBJECTIVE

This guideline reviews the evidence relating to the diagnosis and obstetrical management of diabetes in pregnancy.

OUTCOMES

The outcomes evaluated were short- and long-term maternal outcomes, including preeclampsia, Caesarean section, future diabetes, and other cardiovascular complications, and fetal outcomes, including congenital anomalies, stillbirth, macrosomia, birth trauma, hypoglycemia, and long-term effects.

EVIDENCE

Published literature was retrieved through searches of PubMed and the Cochrane Library using appropriate controlled vocabulary (MeSH terms "diabetes" and "pregnancy"). Where appropriate, results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date limits, but results were limited to English or French language materials.

VALUES

The quality of evidence was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table 1).

SUMMARY STATEMENTS

Recommendations It is recognized that the use of different diagnostic thresholds for the "preferred" and "alternative" strategies could cause confusion in certain settings. Despite this, the committee has identified the importance of remaining aligned with the current Canadian Diabetes Association 2013 guidelines as being a priority. It is thus recommended that each care centre strategically align with 1 of the 2 strategies and implement protocols to ensure consistent and uniform reporting of test results.

Induction of labor before 40 weeks is associated with lower rate of cesarean delivery in women with gestational diabetes mellitus

BACKGROUND

In women with gestational diabetes mellitus, it is not clear whether routine induction of labor at <40 weeks of gestation is beneficial to mother and newborn infant.

OBJECTIVE

The purpose of this study was to compare outcomes among women with gestational diabetes mellitus who had induction of labor at either 38 or 39 weeks with those whose pregnancy was managed expectantly.

STUDY DESIGN

We included all women in Ontario, Canada, with diagnosed gestational diabetes mellitus who had a singleton hospital birth at ≥38 + 0 weeks of gestation between April 2012 and March 2014. Data were obtained from the Better Outcomes Registry & Network Ontario, which is a province-wide registry of all births in Ontario, Canada. Women who underwent induction of labor at 38 + 0 to 38 + 6 weeks of gestation (38-IOL; n = 1188) were compared with those who remained undelivered until 39 + 0 weeks of gestation (38-Expectant; n = 5229). Separately, those women who underwent induction of labor at 39 + 0 to 39 + 6 weeks of gestation (39-IOL; n = 1036) were compared with women who remained undelivered until 40 + 0 weeks of gestation (39-Expectant; n = 2162). Odds ratios and 95% confidence intervals were adjusted for maternal age, parity, insulin treatment, and prepregnancy body mass index.

RESULTS

Of 281,480 women who gave birth during the study period, 14,600 women (5.2%) had gestational diabetes mellitus; of these, 8392 women (57.5%) met all inclusion criteria. Compared with the 38-Expectant group, those women in the 38-IOL group had lower odds for cesarean delivery (adjusted odds ratio, 0.73; 95% confidence interval, 0.52-0.90), higher odds for neonatal intensive care unit admission (adjusted odds ratio, 1.36; 95% confidence interval, 1.09-1.69), and no difference in other maternal-newborn infant outcomes. Compared with the 39-Expectant group, women in the 39-IOL group likewise had lower odds for cesarean delivery (adjusted odds ratio, 0.73; 95% confidence interval, 0.58-0.93) but no difference in neonatal intensive care unit admission (adjusted odds ratio, 0.83; 95% confidence interval, 0.61-1.11).

CONCLUSION

In women with gestational diabetes mellitus, the routine induction of labor at 38 or 39 weeks is associated with a lower risk of cesarean delivery compared with expectant management but may increase the risk of neonatal intensive care unit admission when done at <39 weeks of gestation.

Safety considerations with pharmacological treatment of gestational diabetes mellitus

The number of women with gestational diabetes mellitus (GDM: diabetes first diagnosed in pregnancy) continues to grow, as do the associated risks of antenatal and postnatal complications and the chance of future diabetes and obesity in both mother and offspring. Recent randomised controlled trials have demonstrated clear benefits for intensive management of GDM using lifestyle modification, self blood glucose monitoring, close clinical supervision and, where glycaemia remains inadequately controlled, insulin therapy. More recently, metformin and glibenclamide have been shown to adequately reduce hyperglycaemia as part of a stepped approach to GDM management, with a switch to insulin therapy where necessary. Other oral medications have not been shown to be safe in pregnancy. Human insulin therapy is safe within the limits of hypoglycaemia and weight gain. Most insulin analogues are also now considered safe for use in pregnancy (insulin lispro, aspart and detemir). Metformin therapy is oral, and therefore preferred to insulin, but is associated with more gastrointestinal adverse effects, although not hypoglycaemia or weight gain. Conversely, glibenclamide is also an oral therapy but is associated with hypoglycaemia and weight gain. However, metformin crosses the placenta and it remains unclear whether glibenclamide crosses the placenta or not: long-term risks have not been shown, and are thought to be minimal, but further studies are needed. Metformin is seen by some as the treatment of choice where weight gain is an issue, providing that the unanswered questions over the long-term safety of oral agents have been discussed.

Using oral agents to manage gestational diabetes: what have we learned?

Insulin has been the mainstay of treatment of diabetes during pregnancy for decades. Although glyburide and metformin are classified as category B during pregnancy, recent research has suggested that these oral agents alone or in conjunction with insulin may be safe for the treatment of gestational diabetes (GDM). This paper summarizes the data on the use of glyburide and metformin for treatment of GDM.

Trends in glyburide compared with insulin use for gestational diabetes treatment in the United States, 2000-2011

OBJECTIVE

To describe trends and identify factors associated with choice of pharmacotherapy for gestational diabetes (GDM) from 2000-2011 using a healthcare claims database.

METHODS

This was a retrospective cohort study of a large nationwide population of commercially insured women with GDM and pharmacy claims for glyburide or insulin before delivery, 2000-2011. We excluded women younger than 15 years or older than 50 years, those with prior noninsulin-dependent diabetes mellitus, or those who had multiple gestations. We estimated trends over time in the use of glyburide compared with insulin and prevalence ratios and 95% confidence intervals (CIs) for the association between covariates of interest and treatment with glyburide compared with insulin.

RESULTS

We identified 10,778 women with GDM treated with glyburide (n=5,873) or insulin (n=4,905). From 2000 to 2011, glyburide use increased from 7.4% to 64.5%, becoming the more common treatment in 2007. Women less likely to be treated with glyburide were those with metabolic syndrome (prevalence ratio 0.71, 95% CI 0.50-0.99), hyperandrogenism (prevalence ratio 0.77, 95% CI 0.62-0.97), polycystic ovarian syndrome (prevalence ratio 0.88, 95% CI 0.78-0.99), hypothyroidism (prevalence ratio 0.89, 95% CI 0.83-0.96), or undergoing infertility treatment (prevalence ratio 0.93, 95% CI 0.86-1.02). The probability of receiving glyburide decreased by 5% for every 10-year increase in maternal age (prevalence ratio 0.95, 95% CI 0.91-0.99). Among women prescribed with glyburide, 7.8% switched or augmented to a different drug class compared with 1.1% of insulin initiators.

CONCLUSION

Glyburide has replaced insulin as the more common pharmacotherapy for GDM over the past decade among those privately insured. Given its rapid uptake and the potential implications of suboptimal glucose control on maternal and neonatal health, robust evaluation of glyburide's relative effectiveness is warranted to inform treatment decisions for women with gestational diabetes.

LEVEL OF EVIDENCE

II.

Screening for pregestational and gestational diabetes in pregnancy: a survey of obstetrical centers in the northern part of Belgium

BACKGROUND

There is lack of consensus concerning the best screening strategy for gestational diabetes (GDM). The aim of our survey was therefore to investigate attitudes and practices of all obstetrical centers in the northern part of Belgium regarding screening for pregestational diabetes in early pregnancy and screening for GDM. We also aimed to identify the penetrance of the 'International Association of Diabetes in Pregnancy Study Groups' (IADPSG) screening strategy for GDM.

METHODS

The survey was conducted from May 2012 till January 2013. The survey was distributed to every obstetrical center in the northern part of Belgium by email and/or mail with reminders by phone and personal contact.

RESULTS

From the 65 obstetrical centers, 69% responded. Of all centers, 27% had a structured database on the number of women with GDM. Of all centers, 82% screened for pregestational diabetes in early pregnancy and 56% of centers screened for GDM before 24 weeks. Screening before 24 weeks was mostly based on risk factors. Screening for GDM after 24 weeks, was done universally in 87% of centers. The mean estimated prevalence of GDM was 7 ± 5%. The most commonly used screening strategy was a two-step approach with a glucose challenge test (GCT) and 100 g oral glucose tolerance test (OGTT), used by 56% of centers, with 23 centers using the Carpenter & Coustan criteria. The 75 g OGTT with the IADPSG criteria was used by 33% of centers but 4 of these centers still used a GCT before proceeding to the full OGTT.

CONCLUSIONS

This survey demonstrates that in the northern part of Belgium, there still is a large variation in screening strategy for pregestational diabetes in early pregnancy and GDM. Only 25% of centers have already implemented the one-step IADPSG screening strategy.

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.