Pregnancy outcomes in women with gestational diabetes treated with metformin or insulin: a case-control study

Achievement of Target Glycemic Goal with Simple Basal Insulin Regimen in Women with Gestational Diabetes: A Prospective Cohort Study

There is little evidence concerning the need to treat gestational diabetes (GDM) in the same way as pregestational diabetes. We evaluated the efficacy of the simple insulin injection (SII) regimen for achieving the target glucose goal without increasing adverse perinatal outcomes in singleton pregnant women with GDM. All subjects underwent self-monitoring of blood glucose (SMBG), and insulin therapy was indicated according to the SMBG profile. Insulin was initially started with the SII regimen, in which one daily injection of NPH insulin before breakfast was used, and another NPH injection was added at bedtime, if necessary. We used the target glucose as <95 mg/dL at fasting and <120 mg/dL postprandial and accepted <130 mg/dL for the latter. If the target glucose did not reach with the regimen, we switched to the multiple daily injection (MDI) with additional prandial insulin aspart. We compared the SMBG profile before delivery as well as the perinatal outcomes between the SII and MDI groups. Among 361 women (age 33.7 years, nullipara 41%, prepregnancy body mass index 23.2 kg/m²) with GDM, 59%, 18%, and 23% were in the diet-alone, SII, and MDI groups, respectively. Consequently, regarding women requiring insulin therapy, 43% were treated with the SII regimen throughout pregnancy. The severity of baseline hyperglycemia according to the SMBG data at baseline was the MDI>the SII>the diet group. The rate of achieving target glucose levels before delivery in the SII group at fasting, postprandial < 120 mg/dL and <130 mg/dL were 93%, 54% and 87%, respectively, which were similar to that in the MDI group (93%, 57%, and 93%, respectively), with no significant differences in perinatal outcomes. In conclusion, more than 40% of women with GDM requiring insulin therapy achieved the target glucose goal with this simple insulin regimen without any increase in adverse effects.

Pregnancy Outcomes: Effects of Metformin (POEM) study: a protocol for a long-term, multicentre, open-label, randomised controlled trial in gestational diabetes mellitus

INTRODUCTION

Gestational diabetes mellitus (GDM) is a common disorder of pregnancy with health risks for mother and child during pregnancy, delivery and further lifetime, possibly leading to type 2 diabetes mellitus (T2DM). Current treatment is focused on reducing hyperglycaemia, by dietary and lifestyle intervention and, if glycaemic targets are not reached, insulin. Metformin is an oral blood glucose lowering drug and considered safe during pregnancy. It improves insulin sensitivity and has shown advantages, specifically regarding pregnancy-related outcomes and patient satisfaction, compared with insulin therapy. However, the role of metformin in addition to usual care is inconclusive and long-term outcome of metformin exposure in utero are lacking. The primary aim of this study is to investigate the early addition of metformin on pregnancy and long-term outcomes in GDM.

METHODS AND ANALYSIS

The Pregnancy Outcomes: Effects of Metformin study is a multicentre, open-label, randomised, controlled trial. Participants include women with GDM, between 16 and 32 weeks of gestation, who are randomised to either usual care or metformin added to usual care, with insulin rescue in both groups. Metformin is given up to 1 year after delivery. The study consists of three phases (A-C): A-until 6 weeks after delivery; B-until 1 year after delivery; C-observational study until 20 years after delivery. During phase A, the primary outcome is a composite score consisting of: (1) pregnancy-related hypertension, (2) large for gestational age neonate, (3) preterm delivery, (4) instrumental delivery, (5) caesarean delivery, (6) birth trauma, (7) neonatal hypoglycaemia, (8) neonatal intensive care admission. During phase B and C the primary outcome is the incidence of T2DM and (weight) development in mother and child.

ETHICS AND DISSEMINATION

The study was approved by the Central Committee on Research Involving Human Subjects in the Netherlands. Results will be submitted for publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT02947503.

Gestational Diabetes Mellitus and Preeclampsia: Correlation and Influencing Factors

Gestational diabetes mellitus (GDM) and preeclampsia (PE) are common pregnancy complications with similar risk factors and pathophysiological changes. Evidence from previous studies suggests that the incidence of PE is significantly increased in women with GDM, but whether GDM is independently related to the occurrence of PE has remained controversial. GDM complicated by PE further increases perinatal adverse events with greater impact on the future maternal and offspring health. Identify factors associated with PE in women with GDM women, specifically those that are controllable, is important for improving pregnancy outcomes. This paper provides the findings of a review on the correlation between GDM and PE, factors associated with PE in women with GDM, possible mechanisms, and predictive markers. Most studies concluded that GDM is independently associated with PE in singleton pregnancy, and optimizing the treatment and management of GDM can reduce the incidence of PE, which is very helpful to improve pregnancy outcomes.

Associations between maternal characteristics and pharmaceutical treatment of gestational diabetes: an analysis of the UK Born in Bradford (BiB) cohort study

OBJECTIVES

To identify the maternal characteristics associated with pharmaceutical treatment of gestational diabetes mellitus (GDM).

DESIGN

Prospective birth cohort study.

SETTING

Bradford, UK.

PARTICIPANTS

762 women from the Born in Bradford (BiB) cohort who were treated for GDM in a singleton pregnancy. BiB cohort participants were recruited from 2007 to 2010. All women booked for delivery were screened for GDM between 26 and 28 weeks of gestation using a 75 g 2-hour oral glucose tolerance test (OGTT).

OUTCOME MEASURE

GDM treatment type: lifestyle changes advice (lifestyle changes), lifestyle changes advice with supplementary insulin (insulin) and lifestyle changes advice with supplementary metformin (metformin).

RESULTS

244 (32%) women were prescribed lifestyle changes advice alone while 518 (68%) were offered supplemental pharmaceutical treatment. The odds of receiving pharmaceutical treatment relative to lifestyle changes advice alone were increased for mothers who were obese (OR 4.6, 95% CI 2.8 to 7.5), those who smoked (OR 2.6, 95% CI 1.2 to 5.5) and had higher fasting glucose levels at OGTT (OR 2.1, 95% CI 1.6 to 2.7). The odds of being prescribed pharmaceutical treatment rather than lifestyle changes advice were lower for Pakistani women (OR 0.7, 95% CI 0.4 to 1.0)) than White British women. Relative to insulin treatment, metformin was more likely to be offered to obese women than normal weight women (relative risk ratio, RRR 3.2, 95% CI 1.3 to 7.8) and less likely to be prescribed to women with higher fasting glucose concentrations at OGTT (RRR 0.3, 95% CI 0.2 to 0.6).

CONCLUSIONS

In the BiB cohort, GDM pharmaceutical treatment tended to be prescribed to women who were obese, White British, who smoked and had more severe hyperglycaemia. The characteristics of metformin-treated mothers differed from those of insulin-treated mothers as they were more likely to be obese but had lower glucose concentrations at diagnosis.

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.

The risk of small and large for gestational age newborns in women with gestational diabetes according to pre-gestational body mass index and weight gain

AIM

To explore the effects of pregestational body mass index (BMI) and gestational weight gain (GWG) on maternal and neonatal outcomes of women with gestational diabetes mellitus (GDM).

METHODS

We conducted retrospective cohort analyses of outcomes among women with GDM who delivered at Shamir Medical Center, Israel (2017-2018).

RESULTS

We included 673 women with GDM in our analysis, 217 (32.24%) with appropriate GWG (aGWG), 247 (36.7%) with excessive GWG (eGWG), and 209 (31%) with insufficient GWG (iGWG). Cesarean section (CS) was less prevalent among women with iGWG (19.6%), compared with women with eGWG (31.2%) and aGWG (31.1%) (p = .008). Small for gestational weight (SGA) newborns were more prevalent in women with iGWG 9.1%, compared with 2% and 0.9% for women with eGWG and aGWG, respectively (p<.001). Large for gestational age (LGA) newborns were significantly more prevalent in women with eGWG 17.4% compared with 4.8% and 9.7% in patients with iGWG and aGWG women, respectively (p<.001). SGA and LGA newborns were more prevalent in women with iGWG and e-GWG across all pre-gestational BMI groups >18.5 kg/m².

CONCLUSIONS

A complex interplay exists between pregestational weight, GWG, and GDM and pregnancy outcomes, specifically SGA and LGA newborns. A strict follow-up considering the pregestational BMI, GWG, blood glucose levels, treatment modality, and fetal abdominal circumference could assist in managing the complex interplay of patients with GDM for better neonatal outcomes.

Health Care Providers' Utilization of and Perspectives on Mobile Health Technology for Diabetes and Pregnancy Support

OBJECTIVE

Mobile health (mHealth) technology can be an effective tool to deliver behavioral interventions to improve health outcomes for individuals with diabetes. However, there is limited evidence on mHealth for pregnant women managing diabetes or for the role of health care providers (HCPs) in delivering mHealth tools. To prepare for the development of a pregnancy-specific mHealth intervention for diabetes, we sought to understand HCPs' acceptance, utilization, and design recommendations for how mHealth technology can best be used to support the management of diabetes during pregnancy.

METHODS

Focus groups and individual interviews were conducted with clinical HCPs (obstetricians, nurses, diabetes educators, dietitians, and lactation counselors) who care for low-income pregnant women with diabetes. Data were analyzed using the constant comparative method.

RESULTS

Participants (n = 29) generated five themes and 14 subthemes. Knowledge and acceptance themes included utilization of mobile resources and barriers to HCPs' adoption. Knowledge of popular pregnancy applications (apps) dominated, while familiarity with and use of diabetes apps varied by profession and proximity to continued education. Technology adoption barriers included lack of credibility, dependence on Internet resources, and reliance on knowledge networks. Design themes addressed user-centered design, responsive and practical education, and clinical integration. Clinicians recommended patient-participatory design, customizable features, data-tracking features, motivational feedback, and bidirectional communication capabilities.

CONCLUSION

Although HCPs strongly embraced mHealth tools as an adjunct to obstetric care for women with diabetes, they also expressed limited knowledge and apprehension about patient engagement. HCP recommendations and concerns must critically inform the development of meaningful tools for this population.

Interaction between Metformin, Folate and Vitamin B12 and the Potential Impact on Fetal Growth and Long-Term Metabolic Health in Diabetic Pregnancies

Metformin is the first-line treatment for many people with type 2 diabetes mellitus (T2DM) and gestational diabetes mellitus (GDM) to maintain glycaemic control. Recent evidence suggests metformin can cross the placenta during pregnancy, thereby exposing the fetus to high concentrations of metformin and potentially restricting placental and fetal growth. Offspring exposed to metformin during gestation are at increased risk of being born small for gestational age (SGA) and show signs of ‘catch up’ growth and obesity during childhood which increases their risk of future cardiometabolic diseases. The mechanisms by which metformin impacts on the fetal growth and long-term health of the offspring remain to be established. Metformin is associated with maternal vitamin B₁₂ deficiency and antifolate like activity. Vitamin B₁₂ and folate balance is vital for one carbon metabolism, which is essential for DNA methylation and purine/pyrimidine synthesis of nucleic acids. Folate:vitamin B₁₂ imbalance induced by metformin may lead to genomic instability and aberrant gene expression, thus promoting fetal programming. Mitochondrial aerobic respiration may also be affected, thereby inhibiting placental and fetal growth, and suppressing mammalian target of rapamycin (mTOR) activity for cellular nutrient transport. Vitamin supplementation, before or during metformin treatment in pregnancy, could be a promising strategy to improve maternal vitamin B₁₂ and folate levels and reduce the incidence of SGA births and childhood obesity. Heterogeneous diagnostic and screening criteria for GDM and the transient nature of nutrient biomarkers have led to inconsistencies in clinical study designs to investigate the effects of metformin on folate:vitamin B₁₂ balance and child development. As rates of diabetes in pregnancy continue to escalate, more women are likely to be prescribed metformin; thus, it is of paramount importance to improve our understanding of metformin’s transgenerational effects to develop prophylactic strategies for the prevention of adverse fetal outcomes.

Current Researches, Rationale, Plausibility, and Evidence Gaps on Metformin for the Management of Hypertensive Disorders of Pregnancy

Hypertensive disorders of pregnancy (HDP) are a group of morbid pregnancy complications, with preeclampsia (PE) being the most common subclassification among them. PE affects 2%–8% of pregnancies globally and threatens maternal and fetal health seriously. However, the only effective treatment of PE to date is the timely termination of pregnancy, albeit with increased perinatal risks. Hence, more emerging therapies for PE management are in urgent need. Originally introduced as the first-line therapy for type 2 diabetes mellitus, metformin (MET) has now been found in clinical trials to significantly reduce the incidence of gestational hypertension and PE in pregnant women with PE-related risks, including but not limited to pregestational diabetes mellitus, gestational diabetes mellitus, polycystic ovary syndrome, or obesity. Additionally, existing clinical data have preliminarily ensured the safety of taking MET during human pregnancies. Relevant lab studies have indicated that the underlying mechanism includes angiogenesis promotion, endothelial protection, anti-inflammatory effects, and particularly protective effects on trophoblast cells against the risk factors, which are beneficial to placental development. Together with its global availability, easy administration, and low cost, MET is expected to be a promising option for the prevention and treatment of PE. Nevertheless, there are still some limitations in current studies, and the design of the relevant research scheme is supposed to be further improved in the future. Herein, we summarize the relevant clinical and experimental researches to discuss the rationale, safety, and feasibility of MET for the management of HDP. At the end of the article, gaps in current researches are proposed. Concretely, experimental MET concentration and PE models should be chosen cautiously. Besides, the clinical trial protocol should be further optimized to evaluate the reduction in the prevalence of PE as a primary endpoint. All of those evidence gaps may be of guiding significance to improve the design of relevant experiments and clinical trials in the future.

Oral anti-diabetic drugs as endocrine disruptors in vitro - No evidence for additive effects in binary mixtures

Diabetes is one of the World's most concerning health problems and millions of patients are using anti-diabetic drugs (ADDs) in order to control blood glucose. The in vitro H295R steroidogenesis assay was implemented to investigate endocrine effects of three ADDs, metformin (MET), glimepiride (GLIM), sitagliptin (SIT) and the cholesterol-lowering drug simvastatin (SIM) individually and in three binary mixtures. Steroid hormones were analyzed using LC-MS/MS. Mixture effects were assessed by applying the Concentration Addition (CA) model. All tested drugs and binary mixtures interrupted the H295R steroidogenesis with different potency. The effects of MET:GLIM on the steroidogenesis were overall similar to the steroidogenic profile of GLIM, however effects were less pronounced. The binary mixture of MET:SIT showed overall minor effects on steroid production and only at very high concentrations. The SIM:SIT mixture showed inhibition downstream from cholesterol, which was attributed to the effects of SIM. The CA model partly predicted the effect of MET:SIT on some steroids but significantly overestimated the effects of MET:GLIM and SIM:SIT. Thus, the applicability of the CA model was limited and cocktail effects appeared to be intermediate responses of individual drugs, rather than additive. The complexity of dynamic pathways such as steroidogenesis appears to significantly reduce the use of the CA model. In conclusion, more dynamic models are needed to predict mixture effects in complex systems.

Impact of comorbid polycystic ovarian syndrome and gestational diabetes mellitus on pregnancy outcomes: a retrospective cohort study

BACKGROUND

Gestational diabetes mellitus (GDM) and polycystic ovarian syndrome (PCOS) have been associated with adverse maternal and neonatal outcomes, but the evidence on the impact of coexistent PCOS and GDM is rather limited and inconclusive. We investigated the impact of comorbid PCOS on pregnancy outcomes among women with GDM.

METHODS

This retrospective cohort study included women diagnosed with GDM on 75 g oral glucose tolerance test on routine antenatal screening tests at Liverpool Hospital between February 2015 and January 2019. Women were then grouped into those with and without PCOS based on the Rotterdam criteria. The demographic details, clinical data and pregnancy outcomes were compared between the two groups.

RESULTS

Among the 1545 women with GDM included in the study, there were 326 women with PCOS. Women with GDM and PCOS (GDM⁺PCOS⁺) were younger (29.5 years vs 31.5 years, p < 0.001), more likely to be primigravidae (31.9% vs 20%, p < 0.001), as well as of Caucasian descent (37.4% vs 21.7%, p < 0.001). PCOS was an independent risk factor for the development of preeclampsia on regression analysis (OR 2.06, p = 0.021). Women with PCOS and GDM had a higher body mass index (31.5 kg/m² vs 27.7 kg/m², p < 0.001), significant gestational weight gain (12.6 kg vs 11.5 kg, p = 0.016), and more frequent use of pharmacotherapies to manage their GDM (57.7% vs 45.2%, p < 0.001). There was no statistically significant difference in the rates of adverse neonatal outcomes in both the groups.

CONCLUSION

Among women with GDM, PCOS was an independent risk factor for the development of preeclampsia and significant gestational weight gain, warranting vigilant monitoring of blood pressure, blood glucose levels and body weight, and implementing timely interventions to improve obstetric and neonatal outcomes.

Can maternal treatment with metformin during gestation and lactation cause metabolic and cardiovascular disorders in rat offspring?

Objective: The aim was to evaluate if maternal treatment with metformin (MET) during pregnancy and lactation could be safe for metabolic and cardiovascular parameters of adult male and female offspring.Materials and methods: Wistar female rats were treated with MET (293 mg/kg/d) or tap water, by gavage during gestation (METG or CTRG) or gestation and lactation (METGL or CTRGL).Results: At 75 days of life, male and female MET offspring presented similar blood pressure when compared with their CTR. The heart rate of female METGL was higher than in the CTRGL. The insulin sensitivity, basal glycaemia, body weight, Lee index of obesity, plasmatic concentration of triglycerides, total cholesterol and fat acid of male and female MET were similar to CTR groups. Lower fat pad deposition was observed in female METG and METGL.Conclusion: MET exposure during gestational and lactation does not program cardiovascular and metabolic alterations in adult offspring life.

Predictors of very early postpartum weight loss in women with recent gestational diabetes mellitus

Objective: Women with gestational diabetes (GDM) have a 7-12-fold increased risk for developing type 2 diabetes later in life. Postpartum weight retention is highly predictive for future obesity, and further increases risk for type 2 diabetes. We sought to identify predictors of losing at least 75% of gestational weight gain by very early postpartum in women with recent GDM.Methods: We recruited women with GDM during pregnancy or just after delivery. Prepregnancy weight was self-reported at recruitment; gestational weight gain, mode of delivery, and insulin use were extracted from medical records. At a mean of 7.2 (±2.1) weeks postpartum we measured weight and height and administered questionnaires, including demographics, breastfeeding, Edinburgh Postnatal Depression Scale, sleep, Harvard Food Frequency, and the International Physical Activity Questionnaire. We modeled the odds of 75% loss of gestational weight gain at the study visit using multivariable logistic regression models and selected the model with the lowest Akaike information criterion (AIC) as our final model. Analyses were conducted using JMP 10-13 Pro (SAS Institute Inc.)Results: Seventy-five women with recent GDM were included in the study. The mean age of study participants was 33 (SD ±5) years old, of whom 57% were white, 30% were African American, and 20% of the women identified as Hispanic. The mean prepregnancy BMI was 31.4 kg/m2 (SD ±5.6) and the mean pregnancy weight gain was 12.5 kg (SD ±7.8). Fifty-two percent of participants lost at least 75% of their pregnancy weight gain by the early postpartum study visit. Thirty-seven women (49%) exceeded Institute of Medicine (IOM) guidelines for gestational weight gain. In a multivariate model adjusting for weeks postpartum at the time of the study visit, less gestational weight gain (OR 0.56; 95% CI 0.39-0.73), increased age (OR 1.48; 95% CI 1.13-2.20), and lack of insulin use during pregnancy (OR 0.08 for use of insulin; 95% CI 0.00-0.73) were associated with at least 75% postpartum weight loss. Prepregnancy BMI and sleep were not retained in the model. Race/ethnicity, education, breastfeeding, nulliparity, cesarean section, depressive symptoms, dietary composition, glycemic index, and physical activity did not meet criteria for inclusion in the model.Conclusions: A substantial proportion of women with recent GDM lost at least 75% of their gestational weight gain by early postpartum. Older women, those who did not use insulin during pregnancy and those who gained less weight during pregnancy were significantly more likely to have lost 75% of gestational weight by very early postpartum.

Effects of insulin and metformin on fetal kidney development of streptozotocin-induced gestational diabetic albino rats

Gestational diabetes mellitus is one of common medical complications of pregnancy. Hyperglycemia in utero impairs renal development and produces renal anomalies. Metformin has antioxidant properties and better glycemic control. Aim: assessment insulin and metformin effects on renal development of streptozotocin-induced gestational diabetic albino rats. Sixty virgin female albino rats were used. Once pregnancy confirmed, animals were randomly assigned into control, metformin, diabetic, diabetic plus insulin, diabetic plus metformin and diabetic plus insulin and metformin treated groups. Rats were sacrificed on the 20th day of gestation; fetuses were extracted and weighted. Fetal kidneys were extracted prepared for light, morphometric and electron microscopic examination. Diabetic followed by diabetic plus metformin treated groups revealed retardation of glomerular development in the cortical and Juxtaglomerular zones with a significant increase in the early immature glomerular stages and immature to mature glomerular ratio compared to other groups. Diabetic group also showed morphometric changes, shrunken and empty glomeruli, vacuolar degeneration and hemorrhage. Diabetic plus metformin group showed minimal improvement while diabetic plus insulin and diabetic plus insulin and metformin groups showed developmental, histopathological and morphometric improvement with best results in the combination group. Gestational diabetes mellitus (GDM) possess deleterious effects on fetal kidney development. Insulin improves the glycemic state and decreases GDM effects on fetal kidneys. Metformin produces mild protection while the combination of insulin and metformin produces the best glycemic control and protect fetal kidneys.

Prenatal metformin exposure or organic cation transporter 3 knock-out curbs social interaction preference in male mice

Poorly managed gestational diabetes can lead to severe complications for mother and child including fetal overgrowth, neonatal hypoglycemia and increased autism risk. Use of metformin to control it is relatively new and promising. Yet safety concerns regarding gestational metformin use remain, as its long-term effects in offspring are unclear. In light of beneficial findings with metformin for adult mouse social behavior, we hypothesized gestational metformin treatment might also promote offspring sociability. To test this, metformin was administered to non-diabetic, lean C57BL/6 J female mice at mating, with treatment discontinued at birth or wean. Male offspring exposed to metformin through birth lost social interaction preference relative to controls by time in chambers, but not by sniffing measures. Further, prenatal metformin exposure appeared to enhance social novelty preference only in females. However due to unbalanced litters and lack of statistical power, firm establishment of any sex-dependency of metformin's effects on sociability was not possible. Since organic cation transporter 3 (OCT3) transports metformin and is dense in placenta, social preferences of OCT3 knock-out males were measured. Relative to wild-type, OCT3 knock-outs had reduced interaction preference. Our data indicate gestational metformin exposure under non-diabetic conditions, or lack of OCT3, can impair social behavior in male C57BL6/J mice. Since OCT3 transports serotonin and tryptophan, impaired placental OCT3 function is one common mechanism that could persistently impact central serotonin systems and social behavior. Yet no gross alterations in serotonergic function were evident by measure of serotonin transporter density in OCT3, or serotonin turnover in metformin-exposed offspring brains. Mechanisms underlying the behavioral outcomes, and if with gestational diabetes the same would occur, remain unclear. Metformin's impacts on placental transporters and serotonin metabolism or AMPK activity in fetal brain need further investigation to clarify benefits and risks to offspring sociability from use of metformin to treat gestational diabetes.

The efficacy of metformin compared with insulin in regulating blood glucose levels during gestational diabetes mellitus: A randomized clinical trial

BACKGROUND

Insulin has been a conventional medication in the treatment of female patients suffering from gestational diabetes mellitus (GDM). However, the need for a large number of insulin injections in these patients causes them a lot of discomforts. Recently, an alternative medication, metformin, has received considerable attention in the treatment of GDM. The aim of this study was to compare the efficacy of metformin and insulin in regulating blood glucose levels and fetal outcomes in GDM.

METHODS

This randomized clinical trial included 286 pregnant women diagnosed with positive GDM at 24-28 weeks of pregnancy. The subjects were randomly divided into two groups of 143 patients, with one group receiving insulin and the other undergoing a treatment plan using metformin. Fasting plasma glucose (FPG), 2-hr plasma glucose (PG) and glycated hemoglobin (HbA1c) were recorded twice a month until delivery. Other variables, including birth delivery method, cause of cesarean section, gestational age at the delivery time, birth trauma, Apgar score, birth weight, admission at neonatal intensive care unit (NICU), and neonatal hypoglycemia were also registered.

RESULTS

Age of mother, body mass index, history of diabetes in the family, previous history of GDM, parity, FPG, 1- and 2-hr PG after meals, and 75-g glucose tolerance test before treatment were not statistically different between the two groups. FPG, PG, and HbA1c did not show significant differences between the two groups after completing the course of treatment. There was also no significant difference between two groups regarding the birth delivery method, the cause of cesarean section, birth trauma, Apgar score, birth weight, admission at NICU, and neonatal hypoglycemia.

CONCLUSION

As mean FPG and 2-hr PG were not significantly different between the two groups, it seems that metformin can be recommended as an effective substitute for insulin in the treatment of GDM. However, there are still some undesirable risk factors with both treatments that may threaten the mother and the newborn.

A preclinical overview of metformin for the treatment of type 2 diabetes

Type 2 diabetes (T2D) is the most common type of diabetes mellitus and is mainly characterized by insulin resistance, β-cell dysfunction, and elevated hepatic glucose output. Metformin is a first-line antihyperglycemic agent that works mainly by regulating hepatic glucose production and peripheral insulin sensitivity. Metformin has been clinically applied for more than half a century, although the underlying pharmacological mechanisms remain elusive. This current review mainly focused on the development history of metformin and related preclinical studies on structural modification, pharmacological mechanisms for treatment of T2D, toxicology, pharmacokinetics, and pharmaceutics. The pharmacological function of metformin in lowering hyperglycemia suggests that multi-targeting could be an effective strategy for the discovery of new anti-diabetic drugs. A number of discoveries have revealed the pharmacologic mechanisms of metformin; however, precise mechanisms remain unclear. Deeper investigations on the biological features of metformin are expected to provide more rational applications and indications of this evergreen anti-T2D agent, which will in turn help to better understand the complicated pathogenesis of T2D.

Metformin in Pregnancy: Mechanisms and Clinical Applications

Metformin use in pregnancy is increasing worldwide as randomised controlled trial (RCT) evidence is emerging demonstrating its safety and efficacy. The Metformin in Gestational Diabetes (MiG) RCT changed practice in many countries demonstrating that metformin had similar pregnancy outcomes to insulin therapy with less maternal weight gain and a high degree of patient acceptability. A multicentre RCT is currently assessing the addition of metformin to insulin in pregnant women with type 2 diabetes. RCT evidence is also available for the use of metformin in pregnancy for women with Polycystic Ovarian Syndrome and for nondiabetic women with obesity. No evidence of an increase in congenital malformations or miscarriages has been observed even when metformin is started before pregnancy and continued to term. Body composition and metabolic outcomes at two, seven, and nine years have now been reported for the offspring of mothers treated in the MiG study. In this review, we will briefly discuss the action of metformin and then consider the evidence from the key clinical trials.

Metformin or insulin: logical treatment in women with gestational diabetes in the Middle East, our experience

OBJECTIVE

The debate still continues about the preferred modality of treatment of gestational diabetes requiring pharmacological treatment. Insulin was previously considered as the gold standard, but the National Institute of Health and Care Excellence now recommend metformin as the first line drug of choice. The pharmacological management of gestational diabetes mellitus in the Middle East with its high risk population has not been widely published. We aim to evaluate the safety and efficacy of using metformin in comparison to insulin, in our group of patients, and to study key associated morbidities.

RESULTS

A total of 291 women registered in the clinic during the study period. One hundred and twenty-one (121) were women with gestational diabetes Mellitus requiring medical therapy. Among them, 107 delivered at term. Ninety (84%) women received metformin. Additional insulin was required in 32% of these patients. There was a significant difference in the birth weight of babies in the metformin with insulin group of 207 g (p value 0.04) in favour of metformin. There was no significant difference in maternal or neonatal morbidities between the groups. Metformin was thus found to be a safe, practical and cost effective medication to be offered to our population.

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.

Intrauterine exposure to metformin: Evaluation of endothelial and perivascular adipose tissue function in abdominal aorta of adult offspring

The biguanide metformin (MET) has been used during pregnancy for treatment of polycystic ovary syndrome and gestational diabetes. MET crosses the placenta and maternal treatment can expose the progeny to this drug during important phases of body development. Direct vascular protective effects have been described with the treatment of metformin. Nevertheless, it is unclear whether intrauterine exposure to metformin is safe for the vascular system of offspring. Thus, the present study aimed to investigate the intrinsic effects of metformin exposure in utero in the offspring abdominal aorta reactivity, in the presence and absence of perivascular adipose tissue (PVAT) and endothelium. For this, Wistar rats were treated with metformin 293 mg/kg/day (MET) or water (CTR) by gavage during the gestational period. The abdominal aorta reactivity to phenylephrine, acetylcholine, and sodium nitroprusside was evaluated in male adult offspring. It was observed that abdominal aorta relaxation was similar between MET and CTR groups in the presence or absence of PVAT. In addition, the contraction to phenylephrine was similar between MET and CTR groups in the presence and absence of PVAT and endothelium. Therefore, metformin exposure during pregnancy had no intrinsic effect on the offspring abdominal aorta PVAT and endothelial function, demonstrating it to be safe to the vascular system of the offspring.

Maternal and Neonatal Outcomes in Pregnant Women with Gestational Diabetes Mellitus Treated with Diet, Metformin or Insulin

AIM:

Aim of the study was to compare outcomes of pregnancy in gestational diabetes mellitus (GDM) treated with metformin, insulin, or diet.

MATERIAL AND METHODS:

The study included 48 women with GDM treated with metformin, 101 with insulin, and 200 women on a diet from the Outpatient Department of Endocrinology and University Clinic of Obstetrics and Gynecology in Skopje.

RESULTS:

The groups were comparable in age, smoking cigarettes and positive family history of diabetes. Mean glycosylated haemoglobin (HbA1c) at 37 gestation week, mean fasting, postprandial glycaemia, and gestational age at delivery were lower in diet and metformin than insulin group. No differences in mode of delivery were observed between the metformin and insulin group. Women in metformin group had a significantly lower incidence of LGA newborns than diet and insulin groups. The percent of SGA new-borns was higher in insulin group than diet and metformin groups. The incidence of neonatal hypoglycemia was statistically significantly higher in the insulin group than in the metformin and diet group.

CONCLUSION:

Metformin in women with GDM can improve maternal and neonatal outcomes compared with those treated with diet or insulin.

Outcomes for Women with Gestational Diabetes Treated with Metformin: A Retrospective, Case-Control Study

Metformin is increasingly being used a therapeutic option for the management of gestational diabetes mellitus (GDM). The aim of this study was to compare the maternal characteristics and perinatal outcomes of women with GDM treated with metformin (with or without supplemental insulin) with those receiving other management approaches. A retrospective, case-control study was carried out and 83 women taking metformin were matched 1:1 with women receiving insulin or diet and lifestyle modification alone. Women managed with diet and lifestyle modification had a significantly lower fasting plasma glucose (p < 0.001) and HbA1c (p < 0.01) at diagnosis of GDM. Furthermore, women managed with metformin had a higher early pregnancy body mass index (BMI) compared to those receiving insulin or diet and lifestyle modification (p < 0.001). There was no difference in mode of delivery, birth weight or incidence of large- or small-for-gestational-age neonates between groups. Women receiving glucose lowering therapies had a higher rate of neonatal hypoglycaemia (p < 0.05). The incidence of other adverse perinatal outcomes was similar between groups. Despite their greater BMI, women with metformin-treated GDM did not have an increased risk of adverse perinatal outcomes. Metformin is a useful alternative to insulin in the management of GDM.

How safe is metformin when initiated in early pregnancy? A retrospective 5-year study of pregnant women with gestational diabetes mellitus from India

BACKGROUND

The initiation of metformin in early pregnancy in Gestational Diabetes mellitus (GDM) remains controversial. The aim of our study was to assess the influence of Metformin on maternal and fetal outcomes when initiated within the first trimester of pregnancy in GDM.

METHODS AND MATERIALS

A retrospective analysis of 540 women with diabetes complicating pregnancy (IADPSG criteria) over five years (January 2011 to May 2016) was done. The study population comprised of patients initiated on (a) metformin within the first trimester (Group A:n = 186), (b) metformin after the first trimester (Group B:n = 203) and (c) insulin at any time during their pregnancy (Group C:n = 151). The primary outcomes compared were prematurity, respiratory distress, birth trauma, 5-min APGAR score, neonatal hypoglycaemia and need for phototherapy, while secondary outcomes compared were neonatal anthropometric measurements, maternal glycemic control, maternal hypertensive complications, postpartum glucose tolerance.

RESULTS

Individual and composite primary or secondary outcomes in group A were similar to Groups B and C, though numerically higher premature births were seen in Group A. There was a 1.3% overall incidence of stillbirths/IUD, while 1.11% congenital anomalies were noted of which 2.15% were in group A and 1.32% were in Group C (p = .16).

CONCLUSIONS

The initiation of metformin within the first trimester of pregnancy has no significant adverse maternal or fetal outcomes. However, vigilance for premature births is recommended in women exposed to metformin in early pregnancy.

Metformin in gestational diabetes mellitus: predictors of poor response

OBJECTIVE

Metformin can be regarded as a first-line treatment in gestational diabetes mellitus (GDM) due to its safety and effectiveness. However, a proportion of women do not achieve adequate glycemic control with metformin alone. We aim to identify predictors of this poor response to metformin.

DESIGN AND METHODS

Retrospective multicentre cohort study of women with GDM who started metformin as first-line treatment. The assessed cohort was divided into a metformin group and metformin plus insulin group. Biometric and demographic characteristics, glycemic control data, obstetric, neonatal and postpartum outcomes were compared between groups and analysed in order to identify predictors of poor response to metformin. Data were analysed using STATA, version 13.1.

RESULTS

Of the 388 women enrolled in the study, 135 (34.8%) required additional insulin therapy to achieve the glycemic targets. Higher age (aOR: 1.08 (1.03-1.13), P = 0.003), higher pre-pregnancy body mass index (BMI) (1.06 (1.02-1.10), P = 0.003) and earlier introduction of metformin (0.89 (0.85-0.94), P < 0.001) were independent predictors for insulin supplementation. Regarding all the analysed outcomes, only cesarean delivery rates and postpartum glucose levels were higher in women requiring insulin supplementation.

CONCLUSIONS

Although almost 35% of women did not achieve adequate glycemic control with metformin, insulin supplementation was not associated with poor neonatal outcomes. Higher age, higher pre-pregnancy BMI and earlier introduction of metformin could be used as predictors of poor response to metformin.

Feto-maternal outcomes and Glycemic control in Metformin versus insulin treated Gestational Diabetics

Objective:

To evaluate and compare feto-maternal outcomes and glycemic control in metformin versus insulin treated gestational diabetics.

Methods:

The study was conducted in 2010- 2012 as a part of M. Phil at Civil hospital, Lyari General Hospital and Mamji Hospital in Karachi. After written informed consent, 71 GDM diagnosed females with WHO criteria were enrolled. They were divided into two groups. Group-A, 32 females were given oral metformin 500 mg TDS while Group-B, 39 females were given insulin 0.8-0.9 mg/kg/day in two divided doses subcutaneously. Patients were followed till term. Feto-maternal outcomes were evaluated in 25 patients in each group who completed the study.

Results:

When groups were compared, newborns in Group-B were significantly more in weight (p=0.01). Significant numbers of babies were delivered after 38 weeks of pregnancy in Group-B (P=0.021). There were two intrauterine deaths and significantly higher HbA₁C at term in Group-B. (P=0.03). FBS at term was non-significant (p=0.079) and there was more number of cesarean sections due to feto-maternal disproportion in Group-B (28% vs.2%). Results analyzed for glycemic control before and after the treatment revealed that FBS was statistically less in Group-A (p=0.00) whereas for Group-B the value of FBS and HbA₁C was statistically high. (p=0.002 & 0.04 respectively).

Conclusion:

Metformin has produced better effects on feto-maternal outcomes and glycemic control in comparison to Insulin in GDM.

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.

Efficacy of metformin in improving glycaemic control & perinatal outcome in gestational diabetes mellitus: A non-randomized study

BACKGROUND & OBJECTIVES

Gestational diabetes mellitus (GDM) can cause adverse perinatal outcome if not treated. Although insulin therapy has been the main treatment modality over decades but considering its cost and parenteral mode of administration, it does not seem to be appropriate, especially in low-resource settings. The objective of this study was to evaluate the role of metformin in GDM and know its efficacy as well as adverse effect on foetus and mother.

METHODS

All pregnant women with GDM who were not controlled on medical nutrition therapy and required metformin therapy were included in the study. Careful monitoring of blood sugar was done. Development of any maternal or foetal complications and adverse effect were recorded.

RESULTS

A total of 2797 pregnant women were screened, of whom 233 (8.3%) were found to have GDM. Of the 64 women with GDM (28.7%) who required metformin therapy, majority (93.8%) achieved blood sugar control, whereas three (4.7%) women failed. Caesarean section rate was 54 per cent, and 15.6 per cent neonates were large for gestational age. Only two (3.1%) women had gastrointestinal side effects which were minor and got resolved with time. No case of hypoglycaemia or perinatal mortality was reported.

INTERPRETATION & CONCLUSIONS

Our findings indicate that metformin may be used as a safe and effective oral hypoglycaemic agent in GDM, especially in low-resource settings where cost, storage and compliance are logistic issues. However, long-term follow up studies are needed to solve issues related to its safety in pregnancy.

Neonatal outcomes according to different therapies for gestational diabetes mellitus

OBJECTIVES

To compare different neonatal outcomes according to the different types of treatments used in the management of gestational diabetes mellitus.

METHODS

This was a retrospective cohort study. The study population comprised pregnant women with gestational diabetes treated at a public maternity hospital from July 2010 to August 2014. The study included women aged at least 18 years, with a singleton pregnancy, who met the criteria for gestational diabetes mellitus. Blood glucose levels, fetal abdominal circumference, body mass index and gestational age were considered for treatment decision-making. The evaluated neonatal outcomes were: type of delivery, prematurity, weight in relation to gestational age, Apgar at 1 and 5min, and need for intensive care unit admission.

RESULTS

The sample consisted of 705 pregnant women. The neonatal outcomes were analyzed based on the treatment received. Women treated with metformin were less likely to have children who were small for gestational age (95% CI: 0.09-0.66) and more likely to have a newborn adequate for gestational age (95% CI: 1.12-3.94). Those women treated with insulin had a lower chance of having a preterm child (95% CI: 0.02-0.78). The combined treatment with insulin and metformin resulted in higher chance for a neonate to be born large for gestational age (95% CI: 1.14-11.15) and lower chance to be born preterm (95% CI: 0.01-0.71). The type of treatment did not affect the mode of delivery, Apgar score, and intensive care unit admission.

CONCLUSIONS

The pediatrician in the delivery room can expect different outcomes for diabetic mothers based on the treatment received.

Metformin - a potentially effective drug for gestational diabetes mellitus: a systematic review and meta-analysis

Metformin has been gradually used in the management of gestational diabetes mellitus (GDM). In order to prove the safety and efficacy of metformin used in pregnancy, we searched several databases for the reports of randomized trials comparing insulin and metformin used in GDM and conducted a meta-analysis. Data showed the rates of neonatal large for gestational age, cesarean section, neonatal respiratory distress and preterm birth were similar in both groups. Maternal glycated hemoglobin-% at gestational week 36-37 was significantly lower in metformin group, indicating good glycemic control of metformin. Maternal weight gain since enrollment to gestational week 36-37 was also lower in metformin group, making metformin worth using even when metformin is insufficient and supplementary insulin is needed. Data also showed that metformin significantly reduced the gestational hypertension complications in GDM patients, probably by reducing the endothelial activation and maternal inflammatory response of insulin resistance. Although metformin can cross the placenta, it is less likely to cause severe neonatal hypoglycemia compared with insulin since it neither stimulates pancreatic insulin release nor increases circulating insulin levels. According to most maternal and neonatal outcomes, metformin is an effective and safe alternative to insulin for GDM patients.

Use of metformin earlier in pregnancy predicts supplemental insulin therapy in women with gestational diabetes

The use of metformin in gestational diabetes is safe and effective, yet some women require additional insulin therapy to achieve glycaemic targets. We found a significant association between earlier gestational age at initiation of metformin therapy and the necessity for supplemental insulin in women treated with metformin during pregnancy.

Metformin versus insulin in gestational diabetes mellitus: a meta-analysis of randomized clinical trials

BACKGROUND

Metformin is widely used in treatment of type 2 diabetes. However, whether it is safe for use in pregnancy is controversial.

METHODS

A search for relevant studies were performed using PubMed (1948-2014), Embase (1974-2014), the Web of knowledge (1950-2014), and the Cochrane database, included all randomized control trials published in English.

RESULTS

Eight RCTs (1712 patients with gestational diabetes mellitus) were retrieved; of those 853 patients were given metformin, and 859 patients were given insulin. Our results showed that metformin does not increase risk of prematurity (RR = 1.26; 95 % CI [0.89, 1.79], P = 0.19). In addition, metformin can either decrease the total weight gain [MD = -1.49, 95 % CI (-2.66, -0.31), P = 0.01] or weight gain after randomization [MD = -1.23, 95 % CI (-1.75, -0.71), P < 0.00001]. No significant differences were observed in patients with pre-eclampsia [RR = 0.82, 95 % CI (0.56, 1.2), P = 0.32] or caesarean section [RR = 0.93, 95 % CI (0.75, 1.16), P = 0.53]. Use of metformin also significantly decreased the risk of neonatal hypoglycemia [RR = 0.58, 95 % CI (0.43, 0.78), P = 0.0003] and admission rates to neonatal intensive care units [RR = 0.74, 95 % CI (0.61, 0.89), P = 0.002]. No other adverse effects were observed, such as hyperbilirubinaemia [RR = 0.83, 95 % CI (0.64, 1.08), P = 0.16], large for gestational age [RR = 0.85, 95 % CI (0.68, 1.05), P = 0.14], small for gestational age [RR = 0.92, 95 % CI (0.61, 1.39), P = 0.69], macrosomia [RR = 0.75, 95 % CI (0.54, 1.03), P = 0.07] or respiratory distress syndrome [RR = 0.88, 95 % CI (0.55, 1.41), P = 0.6].

CONCLUSIONS

Metformin may be beneficial in treating gestational diabetes. However, even more studies are needed to provide more evidence for the future use of metformin.

Metformin versus Placebo in Obese Pregnant Women without Diabetes Mellitus

BACKGROUND

Obesity is associated with an increased risk of adverse pregnancy outcomes. Lifestyle-intervention studies have not shown improved outcomes. Metformin improves insulin sensitivity and in pregnant patients with gestational diabetes it leads to less weight gain than occurs in those who do not take metformin.

METHODS

In this double-blind, placebo-controlled trial, we randomly assigned pregnant women without diabetes who had a body-mass index (BMI; the weight in kilograms divided by the square of the height in meters) of more than 35 to receive metformin, at a dose of 3.0 g per day, or placebo (225 women in each group) from 12 to 18 weeks of gestation until delivery. The BMI was calculated at the time of study entry (12 to 18 weeks of gestation). The primary outcome was a reduction in the median neonatal birth-weight z score by 0.3 SD (equivalent to a 50% reduction, from 20% to 10%, in the incidence of large-for-gestational-age neonates). Secondary outcomes included maternal gestational weight gain and the incidence of gestational diabetes and of preeclampsia, as well as the incidence of adverse neonatal outcomes. Randomization was performed with the use of computer-generated random numbers. The analysis was performed according to the intention-to-treat principle.

RESULTS

A total of 50 women withdrew consent during the trial, which left 202 women in the metformin group and 198 in the placebo group. There was no significant between-group difference in the median neonatal birth-weight z score (0.05 in the metformin group [interquartile range, -0.71 to 0.92] and 0.17 in the placebo group [interquartile range, -0.62 to 0.89], P=0.66). The median maternal gestational weight gain was lower in the metformin group than in the placebo group (4.6 kg [interquartile range, 1.3 to 7.2] vs. 6.3 kg [interquartile range, 2.9 to 9.2], P<0.001), as was the incidence of preeclampsia (3.0% vs. 11.3%; odds ratio, 0.24; 95% confidence interval, 0.10 to 0.61; P=0.001). The incidence of side effects was higher in the metformin group than in the placebo group. There were no significant between-group differences in the incidence of gestational diabetes, large-for-gestational-age neonates, or adverse neonatal outcomes.

CONCLUSIONS

Among women without diabetes who had a BMI of more than 35, the antenatal administration of metformin reduced maternal weight gain but not neonatal birth weight. (Funded by the Fetal Medicine Foundation; ClinicalTrials.gov number, NCT01273584; EudraCT number, 2008-005892-83.).

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.

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.

Successful pregnancy outcomes in a patient with type A insulin resistance syndrome

BACKGROUND

The management of severe insulin resistance during pregnancy is challenging because of the increased risk of perinatal complications for both mother and fetus. We describe two consecutive pregnancies in a patient with severe insulin resistance caused by a mutation in the β subunit of the insulin receptor.

CASE REPORT

A non-obese Japanese woman was diagnosed as having diabetes mellitus during her first pregnancy at age 31 years. She presented at 6 weeks' gestation with a fasting plasma glucose concentration of 15.1 mmol/l and an HbA(1c) level of 95 mmol/mol (10.8%). Fasting insulin concentration was high at 68.8 μU/ml, suggesting severe insulin resistance. Anti-insulin and insulin-receptor antibodies were both negative. Genetic analysis revealed an in-frame heterozygous deletion mutation (∆Leu(999)) in the insulin receptor gene. Despite large daily doses (up to 480 units per day) of insulin aspart and isophane, the patient's postprandial plasma glucose level exceeded 11.1 mmol/l. In the patient's second pregnancy, the addition of metformin at a dose of 2250 mg per day achieved tighter glycaemic control, with lower doses of insulin lispro and isophane (up to 174 units/day). Both newborns, who were found to carry the same mutation, were small for gestational age and developed transient hypoglycaemia after birth.

CONCLUSION

Adding metformin to the conventional insulin regimen effectively achieved tight glycaemic control with a lower dose of insulin. The mutation of the insulin receptor gene might underlie the intrauterine growth retardation of the newborns. To our knowledge, this is the first report of successful management of diabetes mellitus in a pregnant woman with type A insulin resistance syndrome.

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.

Use of antidiabetic agents in the treatment of gestational diabetes mellitus in Germany, 2008-2012

AIM

Adequate blood glucose control during pregnancy is important because gestational diabetes mellitus (GDM) is known to have adverse effects on the mother and child. Due to an increasing prevalence of GDM in recent years, more information on the use of different antidiabetic agents is required, which was the aim of the present study.

MATERIAL AND METHODS

Data from 32 diabetic practices in Germany were collected from January 2008 to December 2012 and analyzed using the Disease Analyzer Database. All women with International Classification of Diseases diagnosis O24 (that is, GDM) participated, except for patients with known type I or II diabetes mellitus, who were excluded. Analysis focused on the proportion of women requiring drug treatment in general. Thereafter, subanalysis was performed with a focus on the administration of different antidiabetic agents, namely insulin, metformin, and sulfonylurea.

RESULTS

Within the given timeframe, medication-based treatment for GDM significantly rose to reach 30.8% of all women with GDM. Both the administration of insulin and metformin grew considerably within the 5-year period with metformin being increasingly used without supplemental insulin and at lower dosages. Within the insulin treatment arm, insulin analogues became increasingly important. The proportion of sulfonylurea remained stable (0.2%).

CONCLUSIONS

GDM is more often treated with antidiabetic agents and, due to the fact that metformin is more frequently prescribed, it can be assumed that it is increasingly regarded as a safe and effective alternative to insulin.

Metformin treatment in type 2 diabetes in pregnancy: an active controlled, parallel-group, randomized, open label study in patients with type 2 diabetes in pregnancy

AIMS

To assess the effect of metformin and to compare it with insulin treatment in patients with type 2 diabetes in pregnancy in terms of perinatal outcome, maternal complications, additional insulin requirement, and treatment acceptability.

METHODS

In this randomized, open label study, 206 patients with type 2 diabetes in pregnancy who met the eligibility criteria were selected from the antenatal clinics. Insulin was added to metformin treatment when required, to maintain the target glycemic control. The patients were followed up till delivery. Maternal, and perinatal outcomes and pharmacotherapeutic characteristics were recorded on a proforma.

RESULTS

Maternal characteristics were comparable in metformin and insulin treated group. 84.9% patients in metformin group required add-on insulin therapy at mean gestational age of 26.58 ± 3.85 weeks. Less maternal weight gain (P < 0.001) and pregnancy induced hypertension (P = 0.029) were observed in metformin treated group. Small for date babies were more in metformin group (P < 0.01). Neonatal hypoglycemia was significantly less and so was NICU stay of >24 hours in metformin group (P < 0.01). Significant reduction in cost of treatment was found in metformin group.

CONCLUSION

Metformin alone or with add-on insulin is an effective and cheap treatment option for patients with type 2 diabetes in pregnancy. This trial is registered with clinical trial registration number: Clinical trials.gov NCT01855763.

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).

Metformin versus insulin treatment in gestational diabetes in pregnancy in a developing country: a randomized control trial

AIM

To compare treatment with metformin alone, metformin plus insulin and insulin alone in women with gestational diabetes (GDM).

METHOD

A total of 150 gestational diabetic patients who fulfilled the eligibility criteria were included in this prospective randomized control open labeled study. A risk factor based screening was done followed by a GCT and then local GTT criteria from antenatal clinics. They were initially divided into two groups with odd numbers assigned to metformin treatment and even numbers to insulin treatment. Metformin and/or insulin treatment was given and target blood sugar levels aimed at FBS ≤ 100 mg/dl and postprandial levels ≤ 126 mg/dl. Supplemental insulin was added to metformin treatment group to maintain the glycemic targets if required. Patients were followed until delivery and maternal fetal outcomes and pharmacotherapeutic characteristics were recorded on a performa.

RESULTS

Less maternal weight gain was found in the metformin treated groups (9.8 ± 1.5 kg [metformin alone] vs. 9.8 ± 1.4 kg [metformin plus insulin] vs. 12.5 ± 1.1 kg [insulin alone] P < 0.000). Preeclampsia was significantly less in metformin treated groups. There were no perinatal deaths in the study. Mean birth weight was significantly less in metformin treated groups (3.4 ± 0.4 kg vs. 3.3 ± 0.5 kg vs. 3.7 ± 0.5 kg P < 0.01). Less neonatal morbidity was observed in metformin groups. 42.7% of patients required supplemental insulin (mean dose of 13.6 ± 2 units) in the metformin group. Mean gestational age at which insulin was added was 31.8 ± 5.9 weeks.

CONCLUSION

Metformin is an effective and cheap treatment option for women with gestational diabetes with or without supplemental insulin.