Metformin compared with glyburide for the management of gestational diabetes

15. Management of Diabetes in Pregnancy: Standards of Care in Diabetes-2024

The American Diabetes Association (ADA) "Standards of Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, an interprofessional expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations and a full list of Professional Practice Committee members, please refer to Introduction and Methodology. Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Medications for Managing Preexisting and Gestational Diabetes in Pregnancy

Persons with gestational and pregestational diabetes during pregnancy may require pharmacologic agents to achieve pregnancy glycemic targets, and the available medications for use in pregnancy are limited. Insulin is the only FDA-approved medication for use in pregnancy and has the greatest evidence for safety and efficacy. Metformin and glyburide are the most commonly used oral agents in pregnancy. Understanding each medication's unique pharmacokinetics, potential side effects, fetal or childhood risks, gestational age of medication initiation and patient's diabetes care barriers are important aspects of shared decision-making and choosing a regimen that will achieve glycemic and pregnancy goals.

15. Management of Diabetes in Pregnancy: Standards of Care in Diabetes-2023

The American Diabetes Association (ADA) "Standards of Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations and a full list of Professional Practice Committee members, please refer to Introduction and Methodology. Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Comparison of the effectiveness and safety of insulin and oral hypoglycemic drugs in the treatment of gestational diabetes mellitus: a meta-analysis of 26 randomized controlled trials

OBJECTIVE

Oral hypoglycemic drugs for the treatment of gestational diabetes mellitus (GDM) are still controversial because they can pass through the placenta. The purpose of this meta-analysis is to evaluate the safety and effectiveness of oral hypoglycemic drugs.

METHODS

PubMed, Ovid Embase, Web of Science, and Cochrane databases were systematically searched (inception to 20 April 2021). Rev Man 5.0 was used to analyze the data. A random-effects model was used to compute the summary risk estimates.

RESULTS

There were 26 randomized controlled trials (RCTs) involving 4921 GDM patients which were included in this meta-analysis. Compared with metformin, insulin had a significant increase in the risk of preeclampsia (odds ratio [OR], 1.61; 95% confidence interval [CI], 1.06 to 2.45; I²=40%; p < .05), hypertension (OR, 1.42; 95% CI, 1.02 to 1.99; I²=0%; p < .05), hypoglycemia (OR, 3.93; 95% CI, 1.27 to 12.19; I²=0%; p < .05), neonatal hypoglycemia (OR, 1.92; 95% CI, 1.34 to 2.76; I²=41%; p < .0001), neonatal jaundice (OR, 2.70; 95% CI, 1.12 to 6.52; I²=0%; p < .05), and Neonatal Intensive Care Unit Admission (OR, 1.46; 95% CI, 1.09 to 1.95; I²=39%; p < .05), but the risk of neonatal macrosomia (OR, 1.67; 95% CI, 1.12 to 2.40; I²=0%; p < .05) and neonatal injury (OR, 0.70; 95% CI, 0.55 to 0.89; I²=0%; p < .01) is lower.

CONCLUSIONS

Metformin is comparable with insulin in glycemic control and neonatal outcomes and has the potential to replace insulin therapy in clinical practice. Glyburide is behind metformin and insulin, and more RCTs are needed to verify its safety.

Controversies in Gestational Diabetes

Gestational diabetes mellitus (GDM) complicates approximately 7% of pregnancies in the USA. Despite recognition of the benefits of diagnosing and treating GDM, there are several areas of controversy that remain unresolved. There is debate as to whether to screen for GDM with the one-step versus the two-step approach. While the former identifies more pregnancies with potential adverse outcomes, data are lacking as to whether treatment of these pregnancies will improve outcomes, while increasing costs by diagnosing more women. Though it is well established that the diagnosis of even mild GDM, and treatment with lifestyle recommendations and insulin, improves pregnancy outcomes, it is controversial as to which type and regimen of insulin is optimal, and whether oral agents can be used safely and effectively to control glucose levels. Finally, it is recommended that women with GDM get tested for type 2 diabetes within several months of delivery; however, many women do not undergo this testing and alternative approaches are needed. These controversies are discussed with data from both sides of the debate to enable clinicians to make patient-centered decisions until more definitive data are available.

Metformin versus glyburide in treatment and control of gestational diabetes mellitus: a systematic review with meta-analysis

Objective

Methods

Results

Conclusion

15. Management of Diabetes in Pregnancy: Standards of Medical Care in Diabetes-2022

The American Diabetes Association (ADA) "Standards of Medical Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee (https://doi.org/10.2337/dc22-SPPC), are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations, please refer to the Standards of Care Introduction (https://doi.org/10.2337/dc22-SINT). Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Effects of Different Glucose-Lowering Measures on Maternal and Infant Outcomes in Pregnant Women with Gestational Diabetes: A Network Meta-analysis

INTRODUCTION

A network meta-analysis was conducted to compare and rank the effects of different glucose-lowering measures on maternal and infant outcomes in pregnant women with gestational diabetes mellitus (GDM).

METHODS

We searched the PubMed, CNKI, Embase, Cochrane Library, Wanfang, and Weipu databases for relevant studies published between database establishment and June 2021. Study retrieval involved subject-heading and keyword searches. Randomized controlled trials (RCTs) with different glucose-lowering treatments for GDM patients were included. The Cochrane tool was used to assess bias risk. Pairwise and network meta-analyses were used to compare and rank the effects of different hypoglycemic measures on maternal and infant outcomes in pregnant women with GDM.

RESULTS

We included 41 RCTs involving 6245 pregnant women with GDM. Patients treated with insulin had a higher incidence of neonatal intensive care unit (NICU) occupancy (1.3, 95% CI 1.0-1.7) than those treated with metformin. The insulin (1.5, 95% CI 1.1-2.1 and 1.8, 95% CI 1.0-3.3) and glyburide (2.0, 95% CI 1.2-3.2 and 2.5, 95% CI 1.1-8.4) groups exhibited higher incidences of neonatal hypoglycemia and large for gestational age (LGA) newborns than the metformin group. The glyburide group exhibited a lower probability of cesarean section than the metformin (0.76, 95% CI 0.55-1.0) and insulin (0.71, 95% CI 0.52-0.96) groups. Preeclampsia incidence in the diet and exercise groups was significantly lower than in the metformin (0.19, 95% CI 0.043-0.72) and insulin (0.15, 95% CI 0.032-0.52) groups. No intervention significantly reduced the incidences of macrosomia, preterm birth, gestational hypertension, or respiratory distress syndrome (RDS). The ranking results showed that the metformin group had the lowest rates of neonatal hypoglycemia, macrosomia, LGA, and NICU occupancy. The glyburide group had the lowest NICU occupancy and cesarean section rates and the highest neonatal hypoglycemia, LGA, preeclampsia, and gestational hypertension rates. The diet and exercise group had the lowest preterm delivery and preeclampsia rates and the highest NICU occupancy rate.

CONCLUSION

Metformin is a potentially superior choice for GDM treatment because it is associated with minimal incidences of multiple adverse pregnancy outcome indicators and does not lead to high values of certain adverse outcome indices. Other hypoglycemic agent or diet groups exhibit high incidences of certain adverse outcomes. Therefore, when selecting a GDM treatment strategy, the efficacies and risks of different treatment programs should be evaluated according to the scenario in hand.

Impact of metformin treatment during pregnancy on maternal outcomes: a systematic review/meta-analysis

We systematically assessed the impact of metformin treatment on maternal pregnancy outcomes. PubMed, Ovid Embase, Medline, Web of Science, ClinicalTrials.gov and Cochrane databases were systematically searched (inception-1st February 2021). Randomised controlled trials reporting pregnancy outcomes in women randomised to metformin versus any other treatment for any indication were included. Outcomes included gestational weight gain (GWG), pre-eclampsia, gestational hypertension, preterm birth, gestational age at delivery, caesarean section, gestational diabetes, glycaemic control, and gastrointestinal side-effects. Two independent reviewers conducted screening, with a third available to evaluate disagreements. Risk-of-bias and GRADE assessments were conducted using Cochrane Risk-of-Bias and GRADE-pro software. Thirty-five studies (n = 8033 pregnancies) met eligibility criteria. GWG was lower in pregnancies randomised to metformin versus other treatments (1.57 kg ± 0.60 kg; I₂ = 86%, p < 0.0001), as was likelihood of pre-eclampsia (OR 0.69, 95% CI 0.50-0.95; I₂ = 55%, p = 0.02). The risk of gastrointestinal side-effects was greater in metformin-exposed versus other treatment groups (OR 2.43, 95% CI 1.53-3.84; I₂ = 76%, p = 0.0002). The risk of other maternal outcomes assessed was not significantly different between metformin-exposed versus other treatment groups. Metformin for any indication during pregnancy is associated with lower GWG and a modest reduced risk of pre-eclampsia, but increased gastrointestinal side-effects compared to other treatments.

Metformin is comparable to insulin for pharmacotherapy in gestational diabetes mellitus: A network meta-analysis evaluating 6046 women

CONTEXT

The comparative efficacy of gestational diabetes (GDM) treatments lack conclusive evidence for choice of first-line treatment.

OBJECTIVES

The aim of this study was to compare the efficacy of metformin and glibenclamide to insulin using a core outcome set (COS) to unify outcomes across trials investigating the treatment of gestational diabetes mellitus.

STUDY DESIGN

A network meta-analysis (NMA) was conducted.

DATA-SOURCE

PubMed, Embase, and Cochrane Controlled Register of Trials were searched from inception to January 2020.

STUDY SELECTION

RCTs that enrolled pregnant women who were diagnosed with GDM and that compared the efficacy of different pharmacological interventions for the treatment of GDM were included.

META-ANALYSIS

A generalized pairwise modelling framework was employed.

RESULTS

A total of 38 RCTs with 6046 participants were included in the network meta-analysis. Compared to insulin, the estimated effect of metformin indicated improvements for weight gain (WMD -2·39 kg; 95% CI -3·31 to -1·46), maternal hypoglycemia (OR 0.34; 95% CI 0.12 to 0·97) and LGA (OR 0.61; 95% CI 0.38 to 0·98). There were also improvements in estimated effects for neonatal hypoglycemia (OR 0.48; 95% CI 0.19 to 1·25), pregnancy induced hypertension (OR 0.63; 95% CI 0.37 to 1·06), and preeclampsia (OR 0.74; 95% CI 0.538 to 1·04), though with limited evidence against our model hypothesis of equivalence with insulin for these outcomes.

CONCLUSION

Metformin is, at least, comparable to insulin for the treatment of GDM. Glibenclamide appears less favorable, in comparison to insulin, than metformin.

14. Management of Diabetes in Pregnancy: Standards of Medical Care in Diabetes-2021

The American Diabetes Association (ADA) "Standards of Medical Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee (https://doi.org/10.2337/dc21-SPPC), are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations, please refer to the Standards of Care Introduction (https://doi.org/10.2337/dc21-SINT). Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

A Comparison of Apgar Scores and Changes in the Neonates of Gestational Diabetes Mellitus Patients Treated with Metformin versus Glyburide: A Systematic Review

<b>Aims</b>: This study aims to compare the Apgar scores (at different time points after birth) and their changes between the newborns of gestational diabetes mellitus (GDM) patients treated with metformin and glyburide, respectively. <b>Methods:</b> Electronic databases were searched for randomized controlled trials that compared these outcomes between the above-depicted intervention groups. The data about the study design, the population characteristics, the interventions compared, and the outcomes of interest were extracted from the eligible trials. Then, these trials were critically appraised by the Cochrane tool. After that, the effect of the tested interventions on the respective outcomes of interest was reported narratively. <b><i>Results:</i></b> The literature search produced 4 single-center trials sourcing data from about 538 participants in the USA, Brazil, and Israel. The risk of detection and performance bias was unclear in the respective trials. The trials primarily reported about the Apgar scores at 1 and 5 min after birth. These scores were not different between glyburide- and metformin-treated GDM patients in any trial. No trial reported the Apgar score at 10 min after birth or the changes in Apgar score between 1, 5, or 10 min after birth. <b><i>Conclusion:</i></b> In all trials, the Apgar scores at 1 and 5 min after birth did not vary between the newborns of GDM mothers treated with metformin and glyburide, respectively.

Comparative impact of pharmacological treatments for gestational diabetes on neonatal anthropometry independent of maternal glycaemic control: A systematic review and meta-analysis

BACKGROUND

Fetal growth in gestational diabetes mellitus (GDM) is directly linked to maternal glycaemic control; however, this relationship may be altered by oral anti-hyperglycaemic agents. Unlike insulin, such drugs cross the placenta and may thus have independent effects on fetal or placental tissues. We investigated the association between GDM treatment and fetal, neonatal, and childhood growth.

METHODS AND FINDINGS

PubMed, Ovid Embase, Medline, Web of Science, ClinicalTrials.gov, and Cochrane databases were systematically searched (inception to 12 February 2020). Outcomes of GDM-affected pregnancies randomised to treatment with metformin, glyburide, or insulin were included. Studies including preexisting diabetes or nondiabetic women were excluded. Two reviewers independently assessed eligibility and risk of bias, with conflicts resolved by a third reviewer. Maternal outcome measures were glycaemic control, weight gain, and treatment failure. Offspring anthropometric parameters included fetal, neonatal, and childhood weight and body composition data. Thirty-three studies (n = 4,944), from geographical locations including Europe, North Africa, the Middle East, Asia, Australia/New Zealand, and the United States/Latin America, met eligibility criteria. Twenty-two studies (n = 2,801) randomised women to metformin versus insulin, 8 studies (n = 1,722) to glyburide versus insulin, and 3 studies (n = 421) to metformin versus glyburide. Eleven studies (n = 2,204) reported maternal outcomes. No differences in fasting blood glucose (FBS), random blood glucose (RBS), or glycated haemoglobin (HbA1c) were reported. No studies reported fetal growth parameters. Thirty-three studies (n = 4,733) reported birth weight. Glyburide-exposed neonates were heavier at birth (58.20 g, 95% confidence interval [CI] 10.10-106.31, p = 0.02) with increased risk of macrosomia (odds ratio [OR] 1.38, 95% CI 1.01-1.89, p = 0.04) versus neonates of insulin-treated mothers. Metformin-exposed neonates were born lighter (-73.92 g, 95% CI -114.79 to -33.06 g, p < 0.001) with reduced risk of macrosomia (OR 0.60, 95% CI 0.45-0.79, p < 0.001) than insulin-exposed neonates. Metformin-exposed neonates were born lighter (-191.73 g, 95% CI -288.01 to -94.74, p < 0.001) with a nonsignificant reduction in macrosomia risk (OR 0.32, 95% CI 0.08-1.19, I2 = 0%, p = 0.09) versus glyburide-exposed neonates. Glyburide-exposed neonates had a nonsignificant increase in total fat mass (103.2 g, 95% CI -3.91 to 210.31, p = 0.06) and increased abdominal (0.90 cm, 95% CI 0.03-1.77, p = 0.04) and chest circumferences (0.80 cm, 95% CI 0.07-1.53, p = 0.03) versus insulin-exposed neonates. Metformin-exposed neonates had decreased ponderal index (-0.13 kg/m3, 95% CI -0.26 to -0.00, p = 0.04) and reduced head (-0.21, 95% CI -0.39 to -0.03, p = 0.03) and chest circumferences (-0.34 cm, 95% CI -0.62 to -0.05, p = 0.02) versus the insulin-treated group. Metformin-exposed neonates had decreased ponderal index (-0.09 kg/m3, 95% CI -0.17 to -0.01, p = 0.03) versus glyburide-exposed neonates. Study limitations include heterogeneity in dosing, heterogeneity in GDM diagnostic criteria, and few studies reporting longitudinal growth outcomes.

CONCLUSIONS

Maternal randomisation to glyburide resulted in heavier neonates with a propensity to increased adiposity versus insulin- or metformin-exposed groups. Metformin-exposed neonates were lighter with reduced lean mass versus insulin- or glyburide-exposed groups, independent of maternal glycaemic control. Oral anti-hyperglycaemics cross the placenta, so effects on fetal anthropometry could result from direct actions on the fetus and/or placenta. We highlight a need for further studies examining the effects of intrauterine exposure to antidiabetic agents on longitudinal growth, and the importance of monitoring fetal growth and maternal glycaemic control when treating GDM. This review protocol was registered with PROSPERO (CRD42019134664/CRD42018117503).

14. Management of Diabetes in Pregnancy: Standards of Medical Care in Diabetes-2020

The American Diabetes Association (ADA) "Standards of Medical Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee (https://doi.org/10.2337/dc20-SPPC), are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations, please refer to the Standards of Care Introduction (https://doi.org/10.2337/dc20-SINT). Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Gut microbiota and probiotic intervention as a promising therapeutic for pregnant women with cardiometabolic disorders: Present and future directions

Maternal cardiometabolic disorders, such as gestational diabetes mellitus, pre-eclampsia, obesity, and dyslipidemia, are the most common conditions that predispose offspring to risk for future cardiometabolic diseases, needing appropriate therapeutic approach. The implications of microbiota in the pathophysiology of maternal cardiometabolic disorders are progressively emerging and probiotics may be a simple and safe therapeutic strategy for maternal cardiometabolic management. In this review, we argue the importance of cardiometabolic dysfunction during pregnancy and/or lactation on the offspring risk for cardiometabolic disease in later life. In addition, we comprehensively discuss the microbial diversity observed in maternal cardiometabolic disorders and we present the main findings on probiotic intervention as a potential strategy for management of maternal cardiometabolic disorders. Current data reveal that gut microbiota may be transmitted from mother to offspring. Whether targeting microbiota with probiotic intervention during the periconceptional period prevents or delays the onset of cardiometabolic disorders in adult offspring should be tested in future clinical trials.

Comparative Efficacy and Safety of Metformin, Glyburide, and Insulin in Treating Gestational Diabetes Mellitus: A Meta-Analysis

To compare the efficacy and safety of metformin, glyburide, and insulin in treating gestational diabetes mellitus (GDM), a meta-analysis of randomized controlled trials (RCTs) was conducted. PubMed, Embase, CINAHL, Web of Science, and Cochrane Library to November 13, 2018, were searched for RCT adjusted estimates of the efficacy and safety of metformin, glyburide, and insulin treatments in GDM patients. There were 41 studies involving 7703 GDM patients which were included in this meta-analysis; 12 primary outcomes and 24 secondary outcomes were detected and analyzed. Compared with metformin, insulin had a significant increase in the risk of preeclampsia (RR, 0.57; 95% CI, 0.45 to 0.72; P < 0.001), NICU admission (RR, 0.75; 95% CI, 0.64 to 0.87; P < 0.001), neonatal hypoglycemia (RR, 0.57; 95% CI, 0.49 to 0.66; P < 0.001), and macrosomia (RR, 0.68; 95% CI, 0.55 to 0.86; P < 0.05). To the outcomes of birth weight and gestational age at delivery, insulin had a significant increase when compared with metformin (MD, 114.48; 95% CI, 37.32 to 191.64; P < 0.01; MD, 0.23; 95% CI, 0.12 to 0.34; P < 0.001; respectively). Of the two groups between glyburide and metformin, metformin had lower gestational weight gain compared with glyburide (MD, 1.67; 95% CI, 0.26 to 3.07; P < 0.05). Glyburide had a higher risk of neonatal hypoglycemia compared with insulin (RR, 1.76; 95% CI, 1.32 to 2.36; P < 0.001). This meta-analysis found that metformin could be a safe and effective treatment for GDM. However, clinicians should pay attention on the long-term offspring outcomes of the relative data with GDM patients treated with metformin. Compared with insulin, glyburide had a higher increase of neonatal hypoglycemia. The use of glyburide in pregnancy for GDM women appears to be unclear.

Metformin for prevention of hypertensive disorders of pregnancy in women with gestational diabetes or obesity: systematic review and meta-analysis of randomized trials

OBJECTIVE

Metformin has been reported to reduce the risk of pre-eclampsia. It is also known to influence soluble fms-like tyrosine kinase-1 level, which correlates significantly with the gestational age at onset and severity of pre-eclampsia. The main aim of this systematic review and meta-analysis of randomized trials was to determine whether metformin use is associated with the incidence of hypertensive disorders of pregnancy (HDP).

METHODS

MEDLINE (1947 to September 2017), Scopus (1970 to September 2017) and the Cochrane Library (inception to September 2017) were searched for relevant citations in the English language. Only randomized controlled trials on metformin use, reporting the incidence of pre-eclampsia or pregnancy-induced hypertension, were included. Studies on populations with a high probability of metformin use prior to randomization (those with type II diabetes or polycystic ovary syndrome) were excluded. Random-effects models with the Mantel-Haenszel method were used for subgroup analyses. Bayesian random-effects meta-regression was used to summarize the evidence.

RESULTS

In total, 3337 citations matched the search criteria. After evaluating 2536 abstracts and performing full-text review of 52 studies, 15 were included in the review. In women with gestational diabetes, metformin use was associated with a reduced risk of pregnancy-induced hypertension when compared with insulin (relative risk (RR), 0.56; 95% CI, 0.37-0.85; I²  = 0%; 1260 women) and a non-significantly reduced risk of pre-eclampsia (RR, 0.83; 95% CI, 0.60-1.14; I²  = 0%; 1724 women). In obese women, when compared with placebo, metformin use was associated with a non-significant reduction in risk of pre-eclampsia (RR, 0.74; 95% CI, 0.09-6.28; I²  = 86%; 840 women). In women with gestational diabetes, metformin use was also associated with a non-significant reduction in risk of any HDP (RR, 0.71; 95% CI, 0.41-1.25; I²  = 0%; 556 women) when compared with glyburide. When studies were combined using Bayesian random-effects meta-regression, with treatment type as a covariate, the posterior probabilities of metformin having a beneficial effect on the prevention of pre-eclampsia, pregnancy-induced hypertension and any HDP were 92.7%, 92.8% and 99.2%, respectively, when compared with any other treatment or placebo.

CONCLUSIONS

There is a high probability that metformin use is associated with reduced HDP incidence when compared with other treatments or placebo. The small number of studies included in the analysis, the low quality of evidence and the clinical heterogeneity preclude generalization of these results to broader populations. Given the clinical importance of this topic and the magnitude of effect observed in this meta-analysis, further prospective trials are urgently needed. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Attenuation of maternal weight gain impacts infant birthweight: systematic review and meta-analysis

Despite many interventions aiming to reduce excessive gestational weight gain (GWG), it is currently unclear the impact on infant anthropometric outcomes. The aim of this review was to evaluate offspring anthropometric outcomes in studies designed to reduce GWG. A systematic search of seven international databases, one clinical trial registry and three Chinese databases was conducted without date limits. Studies were categorised by intervention type: diet, physical activity (PA), lifestyle (diet + PA), other, gestational diabetes mellitus (GDM) (diet, PA, lifestyle, metformin and other). Meta-analyses were reported as weighted mean difference (WMD) for birthweight and birth length, and risk ratio (RR) for small for gestational age (SGA), large for gestational age (LGA), macrosomia and low birth weight (LBW). Collectively, interventions reduced birthweight, risk of macrosomia and LGA by 71 g (WMD: -70.67, 95% CI -101.90 to -39.43, P&lt;0.001), 16% (RR: 0.84, 95% CI 0.73-0.98, P=0.026) and 19% (RR: 0.81, 95% CI 0.69-0.96, P=0.015), respectively. Diet interventions decreased birthweight and LGA by 99 g (WMD -98.80, 95% CI -178.85 to -18.76, P=0.016) and 65% (RR: 0.35, 95% CI 0.17-0.72, P=0.004). PA interventions reduced the risk of macrosomia by 51% (RR: 0.49, 95% CI 0.26-0.92, P=0.036). In women with GDM, diet and lifestyle interventions reduced birthweight by 211 and 296 g, respectively (WMD: -210.93, 95% CI -374.77 to -46.71, P=0.012 and WMD:-295.93, 95% CI -501.76 to -90.10, P=0.005, respectively). Interventions designed to reduce excessive GWG lead to a small reduction in infant birthweight and risk of macrosomia and LGA, without influencing the risk of adverse outcomes including LBW and SGA.

Oral Agents for the Treatment of Gestational Diabetes

PURPOSE OF REVIEW

To review the current evidence of the safety and efficacy of the use of oral agents for treatment of gestational diabetes (GDM).

RECENT FINDINGS

The use of metformin and glyburide in pregnancy for treatment of GDM has dramatically increased since the early 2000s. Meta-analyses suggest that glyburide may increase the risk for large for gestational (LGA) infants and neonatal hypoglycemia. Conversely, metformin may potentially decrease rates of pregnancy-induced hypertension, LGA, neonatal hypoglycemia, and maternal weight gain. However, recent long-term offspring studies indicate a potential detrimental effect of metformin on fat mass that suggests an effect of such medication on fetal programming. While there have been several novel oral anti-diabetes medications brought to market in the past decade, there is minimal data to guide use and in particular data regarding long-term safety for the exposed offspring of treated women. Most professional societies recommend insulin as first-line treatment of gestational diabetes after failure of lifestyle modification. Both metformin and glyburide cross the placenta and long-term safety data is limited. However, patient satisfaction is substantially higher with use of oral agents, and the current literatures suggest that metformin may reduce several common short-term adverse outcomes related to GDM.

Metformin in the management of diabetes during pregnancy and lactation

This review explores the current place of metformin in the management of gestational diabetes (GDM) and type 2 diabetes during pregnancy and lactation. The rationale and basic pharmacology of metformin usage in pregnancy is discussed along with the evidence from observational and randomized controlled trials in women with GDM or overt diabetes. There seems to be adequate evidence of efficacy and short-term safety of metformin in relation to maternal and neonatal outcomes in GDM, with possible benefits related to lower maternal weight gain and lower risk of neonatal hypoglycemia and macrosomia. Additionally, metformin offers the advantages of oral administration, convenience, less cost and greater acceptability. Metformin may, therefore, be considered in milder forms of GDM where glycemic goals are not attained by lifestyle modification. However, failure rate is likely to be higher in those with an earlier diagnosis of GDM, higher blood glucose, higher body mass index (BMI) or previous history of GDM, and insulin remains the cornerstone of pharmacological treatment in such cases. The use of metformin in type 2 diabetes has been assessed in observational and small randomized trials. Metformin monotherapy in women with overt diabetes is highly unlikely to achieve glycemic targets. Hence, the use should be restricted as adjunct to insulin and may be considered in women with high insulin dose requirements or rapid weight gain. There is clearly a need for more clinical trials to assess the effect of combined insulin plus metformin therapy in pregnancy with type 2 diabetes. Additionally, there is a paucity of data on long-term effects in offspring exposed to metformin in utero. It is imperative to further explore its impact on offspring as metformin has significant transplacental transfer and has the potential to impact the programming of the epigenome. Therefore, caution must be exercised when prescribing metformin in pregnant women. More research is clearly needed before metformin can be considered as standard of care in the management of diabetes during pregnancy.

Pharmacological treatment of gestational diabetes mellitus: point/counterpoint

Controversies persist over the most efficacious pharmacologic treatment for gestational diabetes mellitus. For purposes of accuracy in this article, the individual American College of Obstetricians and Gynecologists Practice Bulletin and American Diabetes Association Standards of Medical Care positions on each issue are quoted and then deliberated with evidence of counter claims presented in point/counterpoint. This is a review of all the relevant evidence for the most holistic picture possible. The main issues are (1) which diabetic drugs cross the placenta, (2) the quality of evidence and data source validity, (3) the rationale for the designation of glucose control as the primary outcome in gestational diabetes mellitus, and (4) which drugs (metformin, glyburide, or insulin) are most effective in improving secondary outcomes. The concept that 1 drug fits all, whether it be insulin, glyburide, or metformin, is a fallacy. Different drugs provide certain benefits but not all the benefits and not to all patients. In addition, the steps in the gestational diabetes mellitus management decision path and the current cost of the use of insulin, glyburide, or metformin are addressed. In the future, we must consider studying the potential of diabetic drugs that currently are used in nonpregnancy and incorporating the concept of precision medicine in the decision tree to maximize pregnancy outcomes.

The identification and treatment of women with hyperglycaemia in pregnancy: an analysis of individual participant data, systematic reviews, meta-analyses and an economic evaluation

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with a higher risk of important adverse outcomes. Practice varies and the best strategy for identifying and treating GDM is unclear.

AIM

To estimate the clinical effectiveness and cost-effectiveness of strategies for identifying and treating women with GDM.

METHODS

We analysed individual participant data (IPD) from birth cohorts and conducted systematic reviews to estimate the association of maternal glucose levels with adverse perinatal outcomes; GDM prevalence; maternal characteristics/risk factors for GDM; and the effectiveness and costs of treatments. The cost-effectiveness of various strategies was estimated using a decision tree model, along with a value of information analysis to assess where future research might be worthwhile. Detailed systematic searches of MEDLINE^® and MEDLINE In-Process & Other Non-Indexed Citations^®, EMBASE, Cumulative Index to Nursing and Allied Health Literature Plus, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Health Technology Assessment database, NHS Economic Evaluation Database, Maternity and Infant Care database and the Cochrane Methodology Register were undertaken from inception up to October 2014.

RESULTS

We identified 58 studies examining maternal glucose levels and outcome associations. Analyses using IPD alone and the systematic review demonstrated continuous linear associations of fasting and post-load glucose levels with adverse perinatal outcomes, with no clear threshold below which there is no increased risk. Using IPD, we estimated glucose thresholds to identify infants at high risk of being born large for gestational age or with high adiposity; for South Asian (SA) women these thresholds were fasting and post-load glucose levels of 5.2 mmol/l and 7.2 mmol/l, respectively and for white British (WB) women they were 5.4 and 7.5 mmol/l, respectively. Prevalence using IPD and published data varied from 1.2% to 24.2% (depending on criteria and population) and was consistently two to three times higher in SA women than in WB women. Lowering thresholds to identify GDM, particularly in women of SA origin, identifies more women at risk, but increases costs. Maternal characteristics did not accurately identify women with GDM; there was limited evidence that in some populations risk factors may be useful for identifying low-risk women. Dietary modification additional to routine care reduced the risk of most adverse perinatal outcomes. Metformin (Glucophage,^® Teva UK Ltd, Eastbourne, UK) and insulin were more effective than glibenclamide (Aurobindo Pharma - Milpharm Ltd, South Ruislip, Middlesex, UK). For all strategies to identify and treat GDM, the costs exceeded the health benefits. A policy of no screening/testing or treatment offered the maximum expected net monetary benefit (NMB) of £1184 at a cost-effectiveness threshold of £20,000 per quality-adjusted life-year (QALY). The NMB for the three best-performing strategies in each category (screen only, then treat; screen, test, then treat; and test all, then treat) ranged between -£1197 and -£1210. Further research to reduce uncertainty around potential longer-term benefits for the mothers and offspring, find ways of improving the accuracy of identifying women with GDM, and reduce costs of identification and treatment would be worthwhile.

LIMITATIONS

We did not have access to IPD from populations in the UK outside of England. Few observational studies reported longer-term associations, and treatment trials have generally reported only perinatal outcomes.

CONCLUSIONS

Using the national standard cost-effectiveness threshold of £20,000 per QALY it is not cost-effective to routinely identify pregnant women for treatment of hyperglycaemia. Further research to provide evidence on longer-term outcomes, and more cost-effective ways to detect and treat GDM, would be valuable.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013004608.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Use of a clinical-laboratory score to guide treatment of gestational diabetes

OBJECTIVE

To assess the outcomes of implementing a clinical-laboratory score in the treatment of pregnant women with gestational diabetes.

METHODS

A retrospective before-and-after implementation analysis was undertaken using data and neonatal outcomes for pregnant women with gestational diabetes treated before (January 2011-December 2012; control group) and after (January 2013-December 2014; score group) introduction of a newly developed score. To evaluate the effects of score adoption, odds ratios with 95% confidence intervals were calculated after adjustment for confounding factors.

RESULTS

The control group included a greater proportion of women treated with diet alone (170/312 [54.5%]) than the study group did (122/391 [31.2%]; P<0.001). By contrast, more women in the study group received metformin (172 [44.0%] vs 77 [24.7%]; P<0.001). The neonatal outcomes, including low Apgar scores at 1 minute and at 5 minutes and neonatal intensive care unit admission, were similar in both groups. Multivariate logistic regression analysis showed that the adoption of the score did not significantly affect the choice of treatment or the birth weight rating.

CONCLUSION

The score served well as an orientation tool in therapeutic decision making and had no negative effect on the treatment choice and perinatal outcomes.

Comparative efficacy and safety of oral antidiabetic drugs and insulin in treating gestational diabetes mellitus: An updated PRISMA-compliant network meta-analysis

BACKGROUND

The safety and efficacy of different drugs in treatment of gestational diabetes mellitus (GDM) patients who could not maintain normal glucose level only through diet and exercise remains to be debated. We performed this network meta-analysis (NAM) to compare and rank different antidiabetic drugs in glucose level control and pregnancy outcomes in GDM patients.

METHODS

We searched PubMed, Cochrane Library, Web of Science, and Embase up to December 31, 2016. Randomized controlled trials (RCTs) related to different drugs in the treatment of GDM patients were enrolled. We extracted the relevant information and assessed the risk of bias with the Cochrane risk of bias tool. We did pair-wise meta-analyses using the fixed-effects model or random-effects model and then adopted random-effects NAM combining both direct and indirect evidence within a Bayesian framework, to calculate the odds ratio (OR) or standardized mean difference (SMD) and to draw a surface under the cumulative ranking curve of the neonatal and maternal outcomes of different treatments in GDM patients.

RESULTS

Thirty-two randomized controlled trials (RCTs) were included in this NAM, including 6 kinds of treatments (metformin, metformin plus insulin, insulin, glyburide, acarbose, and placebo). The results of the NAM showed that regarding the incidence of macrosomia and LGA, metformin had lower incidence than glyburide (OR, 0.5411 and 0.4177). In terms of the incidence of admission to the NICU, insulin had higher incidence compared with glyburide (OR, 1.844). As for the incidence of neonatal hypoglycemia, metformin had lower incidence than insulin and glyburide (OR, 0.6331 and 0.3898), and insulin was lower than glyburide (OR, 0.6236). For mean birth weight, metformin plus insulin was lower than insulin (SMD, -0.5806), glyburide (SMD, -0.7388), and placebo (SMD, -0.6649). Besides, metformin was observed to have lower birth weight than glyburide (SMD, 0.2591). As for weight gain, metformin and metformin plus insulin were lower than insulin (SMD, -0.9166, -1.53). Ranking results showed that glyburide might be the optimum treatment regarding average glucose control, and metformin is the fastest in glucose control for GDM patients; glyburide have the highest incidence of macrosomia, preeclampsia, hyperbilirubinemia, neonatal hypoglycemia, shortest gestational age at delivery, and lowest mean birth weight; metformin (plus insulin when required) have the lowest incidence of macrosomia, PIH, LGA, RDS, low gestational age at delivery, and low birth weight. Besides, insulin had the highest incidence of NICU admission, acarbose had the lowest risk of neonatal hypoglycemia.

CONCLUSION

Our study concluded that metformin is fastest in glucose control, with a more favorable pregnancy outcomes-would be a better option, but its rate of glucose control is the lowest.However, glyburide is the optimumtreatment regarding the rate of glucose control, but withmore adverse outcomes. This NAMbased on 32 RCTs will strongly help to guide further development of management for GDM patients, clinicians should carefully balance the risk-benefit profile of different treatments according to various situations.

Patterns of glucose-lowering therapies and neonatal outcomes in the treatment of gestational diabetes in Canada, 2009-2014

AIM

To examine patterns of use of different glycaemic control agents for treating gestational diabetes mellitus.

METHODS

This was a large, retrospective, population-based cohort study of pregnant women with gestational diabetes from Alberta, Canada. We linked data from the Alberta Vital Statistics - Birth database with administrative claims data. Alberta Vital Statistics - Birth data were used to identify births that occurred between 1 January 2009 and 31 December 2014. We used International Classification of Diseases version 9/10 codes to identify women with gestational diabetes, and we excluded women with pre-existing diabetes.

RESULTS

Our cohort consisted of 16 857 women with gestational diabetes, with a total of 18 761 birth events between 2009 and 2014. Over the study period, the proportion of women with gestational diabetes who were treated with glycaemic control therapies increased from 25.0% to 31.4% (P<0.0001). The number of pregnancies treated with insulin only increased (from 23.6% to 28.3%; P<0.0001), as did the number treated with metformin, +/- insulin (from 1.4% to 3.2%; P<0.0001). Rates of large-for-gestational-age infants were significantly higher among pregnancies treated with insulin only (17%) or metformin (16.5%) than among pregnancies that did not receive any pharmacological treatment (12.8%).

CONCLUSIONS

Our findings show increasing use of insulin and metformin in women with gestational diabetes. Rates of large-for-gestational-age infants were similar among pregnant women receiving either pharmacological treatment, and higher than among pregnant women who did not receive any pharmacological treatment. Future research should explore the long-term outcomes and safety of metformin as an alternative for treating gestational diabetes.

Comparison of glyburide and insulin in the management of gestational diabetes: A meta-analysis

Objective

The aim of this meta-analysis was to determine the efficacy and safety of glyburide as a treatment for gestational diabetes mellitus (GDM) compared to insulin.

Methods

A meta-analysis was conducted to compare the management of gestational diabetes with glyburide and insulin. Studies fulfilling all of the following inclusion criteria were included in this meta-analysis: subjects were women with gestational diabetes requiring drug treatment; the comparison treatment included glyburide vs insulin; one or more outcomes (maternal or neonatal) should be provided in the individual study; the study design should be a randomized control trial. Exclusion criteria: non-RCT studies; non-human data. PubMed, Embase and CENTRAL databases were searched from inception until 10 October 2016.

Results

Ten randomized control trials involving 1194 participants met the inclusion criteria and were included. 13 primary outcomes (6 maternal, 7 neonatal) and 26 secondary outcomes (9 maternal, 17 neonatal) were detected and analyzed in this study. Glyburide significantly increased the risk of any neonatal hypoglycemia [risk ratio (RR), 1.89; 95% confidence interval (95%CI), 1.26 to 2.82; p = 0.002]. Sensitivity analysis confirmed robustness of this result [RR, 2.29; 95%CI, 1.49 to 3.54; p = 0.0002]. No differences were observed between the two groups with respect to birth weights [mean difference (MD), 79; 95%CI, -64 to 221.99; p = 0.28] and the risk of macrosomia [RR, 1.69; 95%CI, 0.57 to 5.08; p = 0.35].

Conclusion

For women with gestational diabetes, no differences in maternal short term outcomes were observed in those treated with glyburide or insulin. However, the incidence of neonatal hypoglycemia was higher in the glyburide group compared to the insulin group.

Lifestyle interventions for the treatment of women with gestational diabetes

BACKGROUND

Gestational diabetes (GDM) is glucose intolerance, first recognised in pregnancy and usually resolving after birth. GDM is associated with both short- and long-term adverse effects for the mother and her infant. Lifestyle interventions are the primary therapeutic strategy for many women with GDM.

OBJECTIVES

To evaluate the effects of combined lifestyle interventions with or without pharmacotherapy in treating women with gestational diabetes.

SEARCH METHODS

We searched the Pregnancy and Childbirth Group's Trials Register (14 May 2016), ClinicalTrials.gov, WHO International Clinical Trials Registry Platform (ICTRP) (14th May 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

We included only randomised controlled trials comparing a lifestyle intervention with usual care or another intervention for the treatment of pregnant women with GDM. Quasi-randomised trials were excluded. Cross-over trials were not eligible for inclusion. Women with pre-existing type 1 or type 2 diabetes were excluded.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by the Cochrane Collaboration. All selection of studies, data extraction was conducted independently by two review authors.

MAIN RESULTS

Fifteen trials (in 45 reports) are included in this review (4501 women, 3768 infants). None of the trials were funded by a conditional grant from a pharmaceutical company. The lifestyle interventions included a wide variety of components such as education, diet, exercise and self-monitoring of blood glucose. The control group included usual antenatal care or diet alone. Using GRADE methodology, the quality of the evidence ranged from high to very low quality. The main reasons for downgrading evidence were inconsistency and risk of bias. We summarised the following data from the important outcomes of this review. Lifestyle intervention versus control groupFor the mother:There was no clear evidence of a difference between lifestyle intervention and control groups for the risk of hypertensive disorders of pregnancy (pre-eclampsia) (average risk ratio (RR) 0.70; 95% confidence interval (CI) 0.40 to 1.22; four trials, 2796 women; I2 = 79%, Tau2 = 0.23; low-quality evidence); caesarean section (average RR 0.90; 95% CI 0.78 to 1.05; 10 trials, 3545 women; I2 = 48%, Tau2 = 0.02; low-quality evidence); development of type 2 diabetes (up to a maximum of 10 years follow-up) (RR 0.98, 95% CI 0.54 to 1.76; two trials, 486 women; I2 = 16%; low-quality evidence); perineal trauma/tearing (RR 1.04, 95% CI 0.93 to 1.18; one trial, n = 1000 women; moderate-quality evidence) or induction of labour (average RR 1.20, 95% CI 0.99 to 1.46; four trials, n = 2699 women; I2 = 37%; high-quality evidence).More women in the lifestyle intervention group had met postpartum weight goals one year after birth than in the control group (RR 1.75, 95% CI 1.05 to 2.90; 156 women; one trial, low-quality evidence). Lifestyle interventions were associated with a decrease in the risk of postnatal depression compared with the control group (RR 0.49, 95% CI 0.31 to 0.78; one trial, n = 573 women; low-quality evidence).For the infant/child/adult:Lifestyle interventions were associated with a reduction in the risk of being born large-for-gestational age (LGA) (RR 0.60, 95% CI 0.50 to 0.71; six trials, 2994 infants; I2 = 4%; moderate-quality evidence). Birthweight and the incidence of macrosomia were lower in the lifestyle intervention group.Exposure to the lifestyle intervention was associated with decreased neonatal fat mass compared with the control group (mean difference (MD) -37.30 g, 95% CI -63.97 to -10.63; one trial, 958 infants; low-quality evidence). In childhood, there was no clear evidence of a difference between groups for body mass index (BMI) ≥ 85th percentile (RR 0.91, 95% CI 0.75 to 1.11; three trials, 767 children; I2 = 4%; moderate-quality evidence).There was no clear evidence of a difference between lifestyle intervention and control groups for the risk of perinatal death (RR 0.09, 95% CI 0.01 to 1.70; two trials, 1988 infants; low-quality evidence). Of 1988 infants, only five events were reported in total in the control group and there were no events in the lifestyle group. There was no clear evidence of a difference between lifestyle intervention and control groups for a composite of serious infant outcome/s (average RR 0.57, 95% CI 0.21 to 1.55; two trials, 1930 infants; I2 = 82%, Tau2 = 0.44; very low-quality evidence) or neonatal hypoglycaemia (average RR 0.99, 95% CI 0.65 to 1.52; six trials, 3000 infants; I2 = 48%, Tau2 = 0.12; moderate-quality evidence). Diabetes and adiposity in adulthood and neurosensory disability in later childhoodwere not prespecified or reported as outcomes for any of the trials included in this review.

AUTHORS' CONCLUSIONS

Lifestyle interventions are the primary therapeutic strategy for women with GDM. Women receiving lifestyle interventions were less likely to have postnatal depression and were more likely to achieve postpartum weight goals. Exposure to lifestyle interventions was associated with a decreased risk of the baby being born LGA and decreased neonatal adiposity. Long-term maternal and childhood/adulthood outcomes were poorly reported.The value of lifestyle interventions in low-and middle-income countries or for different ethnicities remains unclear. The longer-term benefits or harms of lifestyle interventions remains unclear due to limited reporting.The contribution of individual components of lifestyle interventions could not be assessed. Ten per cent of participants also received some form of pharmacological therapy. Lifestyle interventions are useful as the primary therapeutic strategy and most commonly include healthy eating, physical activity and self-monitoring of blood glucose concentrations.Future research could focus on which specific interventions are most useful (as the sole intervention without pharmacological treatment), which health professionals should give them and the optimal format for providing the information. Evaluation of long-term outcomes for the mother and her child should be a priority when planning future trials. There has been no in-depth exploration of the costs 'saved' from reduction in risk of LGA/macrosomia and potential longer-term risks for the infants.

Scientific Evidence for Different Options for GDM Screening and Management: Controversies and Review of the Literature

Background. Gestational diabetes (GDM) affects up to 7% of pregnant women and is associated with several maternal and perinatal morbidities. International organizations suggest several different recommendations regarding how to screen and to manage GDM. Objective. We aimed to analyze the most important and employed guidelines about screening and management of GDM and we investigated existing related literature. Results. We found several different criteria for screening for GDM, for monitoring GDM, and for starting pharmacological therapy. When using IADPSG criteria, GDM rate increased, perinatal outcomes improved, and screening became cost-effective. Compared to no treatment, treatment of women meeting criteria for GDM by IADPSG criteria but not by other less strict criteria has limited evidence for an effect on adverse pregnancy outcomes.

Glyburide Versus Metformin and Their Combination for the Treatment of Gestational Diabetes Mellitus: A Randomized Controlled Study

OBJECTIVE

To compare the efficacy and safety of glyburide versus metformin and their combination for the treatment of gestational diabetes mellitus (GDM).

RESEARCH DESIGN AND METHODS

In this prospective randomized controlled study, we randomly assigned patients with GDM at 13-33 weeks gestation and whose blood glucose was poorly controlled by diet to receive either glyburide or metformin. If optimal glycemic control was not achieved, the other drug was added. If adverse effects occurred, the drug was replaced. If both failed, insulin was given. The primary outcomes were the rate of treatment failure and glycemic control after the first-line medication according to mean daily glucose charts.

RESULTS

Glyburide was started in 53 patients and metformin in 51. In the glyburide group, the drug failed in 18 (34%) patients due to adverse effects (hypoglycemia) in 6 (11%) and lack of glycemic control in 12 (23%). In the metformin group, the drug failed in 15 (29%) patients, due to adverse effects (gastrointestinal) in 1 (2%) and lack of glycemic control in 14 (28%). Treatment success after second-line therapy was higher in the metformin group than in the glyburide group (13 of 15 [87%] vs. 9 of 18 [50%], respectively; P = 0.03). In the glyburide group, nine (17%) patients were eventually treated with insulin compared with two (4%) in the metformin group (P = 0.03). The combination of the drugs reduced the need for insulin from 33 (32%) to 11 (11%) patients (P = 0.0002). Mean daily blood glucose and other obstetrical and neonatal outcomes were comparable between groups, including macrosomia, neonatal hypoglycemia, and electrolyte imbalance.

CONCLUSIONS

Glyburide and metformin are comparable oral treatments for GDM regarding glucose control and adverse effects. Their combination demonstrates a high efficacy rate with a significantly reduced need for insulin, with a possible advantage for metformin over glyburide as first-line therapy.

Different types of dietary advice for women with gestational diabetes mellitus

BACKGROUND

Dietary advice is the main strategy for managing gestational diabetes mellitus (GDM). It remains unclear what type of advice is best.

OBJECTIVES

To assess the effects of different types of dietary advice for women with GDM for improving health outcomes for women and babies.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register (8 March 2016), PSANZ's Trials Registry (22 March 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials comparing the effects of different types of dietary advice for women with GDM.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility, risk of bias, and extracted data. Evidence quality for two comparisons was assessed using GRADE, for primary outcomes for the mother: hypertensive disorders of pregnancy; caesarean section; type 2 diabetes mellitus; and child: large-for-gestational age; perinatal mortality; neonatal mortality or morbidity composite; neurosensory disability; secondary outcomes for the mother: induction of labour; perineal trauma; postnatal depression; postnatal weight retention or return to pre-pregnancy weight; and child: hypoglycaemia; childhood/adulthood adiposity; childhood/adulthood type 2 diabetes mellitus.

MAIN RESULTS

In this update, we included 19 trials randomising 1398 women with GDM, at an overall unclear to moderate risk of bias (10 comparisons). For outcomes assessed using GRADE, downgrading was based on study limitations, imprecision and inconsistency. Where no findings are reported below for primary outcomes or pre-specified GRADE outcomes, no data were provided by included trials. Primary outcomes Low-moderate glycaemic index (GI) versus moderate-high GI diet (four trials): no clear differences observed for: large-for-gestational age (risk ratio (RR) 0.71, 95% confidence interval (CI) 0.22 to 2.34; two trials, 89 infants; low-quality evidence); severe hypertension or pre-eclampsia (RR 1.02, 95% CI 0.07 to 15.86; one trial, 95 women; very low-quality evidence); eclampsia (RR 0.34, 95% CI 0.01 to 8.14; one trial, 83 women; very low-quality evidence) or caesarean section (RR 0.66, 95% CI 0.29 to 1.47; one trial, 63 women; low-quality evidence). Energy-restricted versus no energy-restricted diet (three trials): no clear differences seen for: large-for-gestational age (RR 1.17, 95% CI 0.65 to 2.12; one trial, 123 infants; low-quality evidence); perinatal mortality (no events; two trials, 423 infants; low-quality evidence); pre-eclampsia (RR 1.00, 95% CI 0.51 to 1.97; one trial, 117 women; low-quality evidence); or caesarean section (RR 1.12, 95% CI 0.80 to 1.56; two trials, 420 women; low-quality evidence). DASH (Dietary Approaches to Stop Hypertension) diet versus control diet (three trials): no clear differences observed for: pre-eclampsia (RR 1.00, 95% CI 0.31 to 3.26; three trials, 136 women); however there were fewer caesarean sections in the DASH diet group (RR 0.53, 95% CI 0.37 to 0.76; two trials, 86 women). Low-carbohydrate versus high-carbohydrate diet (two trials): no clear differences seen for: large-for-gestational age (RR 0.51, 95% CI 0.13 to 1.95; one trial, 149 infants); perinatal mortality (RR 3.00, 95% CI 0.12 to 72.49; one trial, 150 infants); maternal hypertension (RR 0.40, 95% CI 0.13 to 1.22; one trial, 150 women); or caesarean section (RR 1.29, 95% CI 0.84 to 1.99; two trials, 179 women). High unsaturated fat versus low unsaturated fat diet (two trials): no clear differences observed for: large-for-gestational age (RR 0.54, 95% CI 0.21 to 1.37; one trial, 27 infants); pre-eclampsia (no cases; one trial, 27 women); hypertension in pregnancy (RR 0.54, 95% CI 0.06 to 5.26; one trial, 27 women); caesarean section (RR 1.08, 95% CI 0.07 to 15.50; one trial, 27 women); diabetes at one to two weeks (RR 2.00, 95% CI 0.45 to 8.94; one trial, 24 women) or four to 13 months postpartum (RR 1.00, 95% CI 0.10 to 9.61; one trial, six women). Low-GI versus high-fibre moderate-GI diet (one trial): no clear differences seen for: large-for-gestational age (RR 2.87, 95% CI 0.61 to 13.50; 92 infants); caesarean section (RR 1.91, 95% CI 0.91 to 4.03; 92 women); or type 2 diabetes at three months postpartum (RR 0.76, 95% CI 0.11 to 5.01; 58 women). Diet recommendation plus diet-related behavioural advice versus diet recommendation only (one trial): no clear differences observed for: large-for-gestational age (RR 0.73, 95% CI 0.25 to 2.14; 99 infants); or caesarean section (RR 0.78, 95% CI 0.38 to 1.62; 99 women). Soy protein-enriched versus no soy protein diet (one trial): no clear differences seen for: pre-eclampsia (RR 2.00, 95% CI 0.19 to 21.03; 68 women); or caesarean section (RR 1.00, 95% CI 0.57 to 1.77; 68 women). High-fibre versus standard-fibre diet (one trial): no primary outcomes reported. Ethnic-specific versus standard healthy diet (one trial): no clear differences observed for: large-for-gestational age (RR 0.14, 95% CI 0.01 to 2.45; 20 infants); neonatal composite adverse outcome (no events; 20 infants); gestational hypertension (RR 0.33, 95% CI 0.02 to 7.32; 20 women); or caesarean birth (RR 1.20, 95% CI 0.54 to 2.67; 20 women). Secondary outcomes For secondary outcomes assessed using GRADE no differences were observed: between a low-moderate and moderate-high GI diet for induction of labour (RR 0.88, 95% CI 0.33 to 2.34; one trial, 63 women; low-quality evidence); or an energy-restricted and no energy-restricted diet for induction of labour (RR 1.02, 95% CI 0.68 to 1.53; one trial, 114 women, low-quality evidence) and neonatal hypoglycaemia (average RR 1.06, 95% CI 0.48 to 2.32; two trials, 408 infants; very low-quality evidence).Few other clear differences were observed for reported outcomes. Longer-term health outcomes and health services use and costs were largely not reported.

AUTHORS' CONCLUSIONS

Evidence from 19 trials assessing different types of dietary advice for women with GDM suggests no clear differences for primary outcomes and secondary outcomes assessed using GRADE, except for a possible reduction in caesarean section for women receiving a DASH diet compared with a control diet. Few differences were observed for secondary outcomes.Current evidence is limited by the small number of trials in each comparison, small sample sizes, and variable methodological quality. More evidence is needed to assess the effects of different types of dietary advice for women with GDM. Future trials should be adequately powered to evaluate short- and long-term outcomes.

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.

Pharmacological Management of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is one of the most common morbidities complicating pregnancy, with short- and long-term consequences to the mothers, fetuses, and newborns. Management and treatment are aimed to achieve best possible glycemic control, while avoiding hypoglycemia and ensuring maternal and fetal safety. It involves behavioral modifications, nutrition and medications, if needed; concurrent with maternal and fetal surveillance for possible adverse outcomes. This review aims to elaborate on the pharmacological options for GDM therapy. We performed an extensive literature review of different available studies, published during the last 50 years, concerning pharmacological therapy for GDM, dealing with safety and efficacy, for both fetal and maternal morbidity consequences; as well as failure and success in establishing appropriate metabolic and glucose control. Oral medication therapy is a safe and effective treatment modality for GDM and in some circumstances may serve as first-line therapy when nutritional modifications fail. When oral agents fail to establish glucose control then insulin injections should be added. Determining the best oral therapy in inconclusive, although it seems that metformin is slightly superior to glyburide, in some aspects. As for parenteral therapy, all insulins listed in this article are considered both safe and effective for treatment of hyperglycemia during pregnancy. Importantly, a better safety profile, with similar efficacy is documented for most analogues. As GDM prevalence rises, there is a need for successful monitoring and treatment for patients. Caregivers should know the possible and available therapeutic options.

Efficacy and safety of metformin for the treatment of gestational diabetes: a new approach to the problem

Historically, the following two methods were used to treat gestational diabetes mellitus: non-medical life-style interventions (diet and increased physical activity) and insulin treatment when other interventions were not effective. The possibility of alternative types of treatment such as oral anti-diabetic drugs has been the source of debate in recent years. Metformin is an oral anti-diabetic drug that reduces insulin resistance, which is common during gestation and is considered one of the main pathways of glucose metabolism alteration during pregnancy. The main concern is that metformin can cross the placenta and is found unchanged in foetal blood. This is the reason why oral anti-diabetic drugs are contraindicated during pregnancy in many countries, including Russia (according to the 2012 Russian recommendations for gestational diabetes treatment). In recent years, many studies investigating the safety and efficacy of metformin for maternal and foetal health have been published. We will review recent randomized clinical trials and discuss new international clinical recommendations (FIGO, 2015) and new opportunities for gestational diabetes mellitus treatment. 

Oral hypoglycemic agents: do the ends justify the means?

BACKGROUND

Glyburide has replaced insulin as the first line of therapy in the treatment of gestational diabetes in the United States. Glyburide and metformin therapies were reported to be comparable to insulin yet also cost-effective, patient-friendly, and potentially compliance-enhancing. Recently, the efficacy of the use of these oral hypoglycemic drugs has been questioned. In this review, the questionable concerns will be addressed: Which diabetic drug(s) cross the placenta? What is the quality of evidence and the data source validity? Which treatment modalities are most effective in reducing the primary outcome in GDM? Which drug is most effective in improving secondary outcomes?

FINDINGS

This review documents the methodological issues in study design that have impacted the results for the provision of health care interventions in GDM. The review summarizes the contents of the articles qualitatively and assesses the theoretical and empirical evidence. Multiple types of studies exist and every study design serves a specific purpose. Different study designs addressing the same question can yield varying results. The risk of presenting uncertain results without categorically knowing the direction and magnitude of the effect holds true for both randomized and nonrandomized controlled trials. The review further emphasizes the importance of achieving the targeted levels of glycemic control.

CONCLUSION

The implications of this review are critical to addressing the current gaps in the literature on the efficacy of the use of oral hypoglycemic agents in GDM. The emphasis needs to be placed on patient treatment in order to manage hyperglycemia to reduce fetal and maternal morbidity. In this regard, we need to delineate proper outcome criteria that will reflect disease severity and treat using appropriate pharmacological therapy.

A review of current treatment strategies for gestational diabetes mellitus

Approximately 90% of diabetes cases in pregnant women are considered gestational diabetes mellitus (GDM). It is well known that uncontrolled glucose results in poor pregnancy outcomes in both the mother and fetus. Worldwide there are many guidelines with recommendations for appropriate management strategies for GDM once lifestyle modifications have been instituted and failed to achieve control. The efficacy and particularly the safety of other treatment modalities for GDM has been the source of much debate in recent years. Studies that have demonstrated the safety and efficacy of both glyburide and metformin in the management of patients with GDM will be reviewed. There is a lack of evidence with other oral and injectable non-insulin agents to control blood glucose in GDM. The role of insulin will be discussed, with emphasis on insulin analogs. Ideal patient characteristics for each treatment modality will be reviewed. In addition, recommendations for postpartum screening of patients will be described as well as recommendations for use of agents to manage subsequent type 2 diabetes in patients who are breastfeeding.

Recognition and Management of Individuals With Hyperglycemia Because of a Heterozygous Glucokinase Mutation

Glucokinase-maturity-onset diabetes of the young (GCK-MODY), also known as MODY2, is caused by heterozygous inactivating mutations in the GCK gene. GCK gene mutations are present in ∼1 in 1,000 of the population, but most are not diagnosed. They are common causes of MODY (10-60%): persistent incidental childhood hyperglycemia (10-60%) and gestational diabetes mellitus (1-2%). GCK-MODY has a unique pathophysiology and clinical characteristics, so it is best considered as a discrete genetic subgroup. People with GCK-MODY have a defect in glucose sensing; hence, glucose homeostasis is maintained at a higher set point resulting in mild, asymptomatic fasting hyperglycemia (5.4-8.3 mmol/L, HbA1c range 5.8-7.6% [40-60 mmol/mol]), which is present from birth and shows slight deterioration with age. Even after 50 years of mild hyperglycemia, people with GCK-MODY do not develop significant microvascular complications, and the prevalence of macrovascular complications is probably similar to that in the general population. Treatment is not recommended outside pregnancy because glucose-lowering therapy is ineffective in people with GCK-MODY and there is a lack of long-term complications. In pregnancy, fetal growth is primarily determined by whether the fetus inherits the GCK gene mutation from their mother. Insulin treatment of the mother is only appropriate when increased fetal abdominal growth on scanning suggests the fetus is unaffected. The impact on outcome of maternal insulin treatment is limited owing to the difficulty in altering maternal glycemia in these patients. Making the diagnosis of GCK-MODY through genetic testing is essential to avoid unnecessary treatment and investigations, especially when patients are misdiagnosed with type 1 or type 2 diabetes.

Evidence-based strategies for managing gestational diabetes in women with obesity

Pregnancies complicated by both obesity and gestational diabetes mellitus (GDM) increase the risk of maternal and fetal complications, including but not limited to gestational hypertension, cesarean surgical birth, fetal macrosomia and postpartum hemorrhage. Because of the increased maternal and fetal risks associated with maternal obesity and GDM, the development of evidence-based strategies for screening for and management of GDM and for timing of birth will provide a comprehensive approach needed to optimize outcomes for both women and newborns.

Changing trends in management of gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is on the rise globally. In view of the increasing prevalence of GDM and fetal and neonatal complications associated with it, there is a splurge of research in this field and management of GDM is undergoing a sea change. Trends are changing in prevention, screening, diagnosis, treatment and future follow up. There is emerging evidence regarding use of moderate exercise, probiotics and vitamin D in the prevention of GDM. Regarding treatment, newer insulin analogs like aspart, lispro and detemir are associated with better glycemic control than older insulins. Continuous glucose monitoring systems and continuous subcutaneous insulin systems may play a role in those who require higher doses of insulin for sugar control. Evidence exists that favors metformin as a safer alternative to insulin in view of good glycemic control and better perinatal outcomes. As the risk of developing GDM in subsequent pregnancies and also the risk of overt diabetes in later life is high, regular assessment of these women is required in future. Lifestyle interventions or metformin should be offered to women with a history of GDM who develop pre-diabetes. Further studies are required in the field of prevention of GDM for optimizing obstetric outcome.

Metformin in gestational diabetes: An emerging contender

Gestational diabetes mellitus (GDM) is defined as any degree of glucose intolerance occurring first time during pregnancy. Its prevalence is simultaneously increasing with the global rise of diabesity. GDM commonly develops, when maternal glucose metabolism is unable to compensate for the progressive development of insulin resistance, arising primarily from the consistently rising diabetogenic placental hormones. It classically develops during the second or third trimester. Theoretically, insulin sensitizers should have been the ideal agent in its treatment, given the insulin resistance, the major culprit in its pathogenesis. Fortunately, majority of women can be treated satisfactorily with lifestyle modification, and approximately 20% requires more intensive treatment. For several decades, insulin has been the most reliable treatment strategy and the gold standard in GDM. Metformin is effective insulin sensitizing agent and an established first line drug in type 2 diabetes currently. As it crosses the placenta, a safety issue remains an obstacle and, therefore, metformin is currently not recommended in the treatment of GDM. Nevertheless, given the emerging clinically equivalent safety and efficacy data of metformin compared to insulin, it appears that it may perhaps open a rather new door in managing GDM. The aim of this review is to critically analyze, the safety and efficacy data of metformin regarding its use in GDM and pregnant mothers with polycystic ovarian disease, which has emerged in past decades.

Oral antidiabetic agents in gestational diabetes: a narrative review of current evidence

Gestational diabetes mellitus (GDM) classically occurs when maternal glucose metabolism is unable to compensate the progressive development of insulin resistance that arises from the continuously rising diabetogenic placental hormones. Although most women can be treated satisfactorily with diet alone, some require more intensive treatment. Insulin has been the most reliable treatment strategy in GDM over several decades. Although a long time has passed since the publication of two randomized controlled trials suggesting comparable efficacy and safety of metformin and glibenclamide, international bodies have not yet approved these oral agents. However, with the consistently emerging efficacy and safety data of these two drugs in the past decade, they may perhaps open a rather new door. The aim of this narrative review is to critically evaluate the existing evidence regarding safety and efficacy of oral drugs in GDM accumulated since the first publication in year 2000, suggesting clinical equivalency of glibenclamide (glyburide).

Use of oral anti-diabetic agents in pregnancy: a pragmatic approach

Insulin is the gold standard for treatment of hyperglycemia during pregnancy, when lifestyle measures do not maintain glycemic control during pregnancy. However, recent studies have suggested that certain oral hypoglycemic agents (metformin and glyburide) may be safe and be acceptable alternatives. There are no serious safety concerns with metformin, despite it crossing the placenta. Neonatal outcomes are also comparable, with benefit of reductions in neonatal hypoglycemia, maternal hypoglycemia and weight gain, and improved treatment satisfaction. Glibenclamide is more effective in lowering blood glucose in women with gestational diabetes, and with a lower treatment failure rate than metformin. Although generally well-tolerated, some studies have reported higher rates of pre-eclampsia, neonatal jaundice, longer stay in the neonatal care unit, macrosomia, and neonatal hypoglycaemia. There is also paucity of long-term follow-up data on children exposed to oral agents in utero. This review aims to provide an evidence-based approach, concordant with basic and clinical pharmacological knowledge, which will help medical practitioners use oral anti-diabetic agents in a rational and pragmatic manner. Pubmed search was made using Medical Subject Headings (MESH) terms “Diabetes” and “Pregnancy” and “Glyburide”; “Diabetes” and “Pregnancy” and “Metformin”. Limits were randomized controlled trials (RCTs) and meta-analysis. The expert reviews on the topic were also used for discussion. Additional information (studies/review) pertaining to discussion under sub-headings like safety during breastfeeding; placental transport; long-term safety data were searched (pubmed/cross-references/expert reviews).

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.