Metformin therapy throughout pregnancy reduces the development of gestational diabetes in women with polycystic ovary syndrome

Repurposing Metformin for the Treatment of Atrial Fibrillation: Current Insights

Metformin is an orally effective anti-hyperglycemic drug that despite being introduced over 60 years ago is still utilized by an estimated 120 to 150 million people worldwide for the treatment of type 2 diabetes (T2D). Metformin is used off-label for the treatment of polycystic ovary syndrome (PCOS) and for pre-diabetes and weight loss. Metformin is a safe, inexpensive drug with side effects mostly limited to gastrointestinal issues. Prospective clinical data from the United Kingdom Prospective Diabetes Study (UKPDS), completed in 1998, demonstrated that metformin not only has excellent therapeutic efficacy as an anti-diabetes drug but also that good glycemic control reduced the risk of micro- and macro-vascular complications, especially in obese patients and thereby reduced the risk of diabetes-associated cardiovascular disease (CVD). Based on a long history of clinical use and an excellent safety record metformin has been investigated to be repurposed for numerous other diseases including as an anti-aging agent, Alzheimer's disease and other dementias, cancer, COVID-19 and also atrial fibrillation (AF). AF is the most frequently diagnosed cardiac arrythmia and its prevalence is increasing globally as the population ages. The argument for repurposing metformin for AF is based on a combination of retrospective clinical data and in vivo and in vitro pre-clinical laboratory studies. In this review, we critically evaluate the evidence that metformin has cardioprotective actions and assess whether the clinical and pre-clinical evidence support the use of metformin to reduce the risk and treat AF.

Anthropometrics of neonates born to mothers with PCOS with metformin or placebo exposure in utero

INTRODUCTION

Fetal growth may be affected by both maternal polycystic ovary syndrome (PCOS) and metformin therapy. Here, we explore the effect of intrauterine metformin exposure on birth anthropometrics of infants born to women with PCOS. We also investigated whether the effect of metformin on birth anthropometrics is modified by maternal pre-pregnancy body mass index, PCOS hyperandrogenic phenotype, serum androgen levels, preconception use of metformin and offspring sex. Additionally, we assessed newborn anthropometrics in relation to a national reference population.

MATERIAL AND METHODS

Individual data from three randomized controlled triasl were pooled. The randomized controlled trials investigated the effects of metformin in pregnant women with PCOS. In all, 397 and 403 were randomized to the metformin and placebo groups, respectively. A Scandinavian growth reference was used to calculate sex and gestational age adjusted z-scores. Linear regression models were used to estimate the effect of metformin on offspring z-scores of head circumference, birth length, birthweight, placental weight, body mass index, ponderal index and birthweight:placental weight ratio. S-testosterone, s-androstenedione, and s-sex-hormone binding globulin from four timepoints in pregnancy were analyzed.

RESULTS

Compared with the PCOS-placebo group, newborns in the PCOS-metformin group had larger head circumference (head circumference z-score: mean difference = 0.25, 95% CI = 0.11- 0.40). This effect of metformin on head circumference z-score was particularly observed among offspring of overweight/obese mothers and mothers with hyperandrogenic PCOS-phenotype. We observed no difference in other anthropometric measures between the metformin and placebo groups or any clear interaction between maternal androgen levels and metformin. Newborns in the PCOS-placebo group were shorter than in the reference population (birth length z-score: mean = -0.04, 95% CI = -0.05 to -0.03), but head circumference and birthweight were similar.

CONCLUSIONS

Larger head circumference was observed at birth in metformin-exposed offspring of mothers with PCOS. PCOS-offspring were also shorter, with a similar birthweight to the reference population, indirectly indicating higher weight-to-height ratio at birth.

Management of type 2 diabetes in pregnancy: a narrative review

The prevalence of type 2 diabetes (T2DM) at reproductive age is rising. Women with T2DM have a similarly high risk for pregnancy complications as pregnant women with type 1 diabetes. To reduce adverse pregnancy and neonatal outcomes, such as preeclampsia and preterm delivery, a multi-target approach is necessary. Tight glycemic control together with appropriate gestational weight gain, lifestyle measures, and if necessary, antihypertensive treatment and low-dose aspirin is advised. This narrative review discusses the latest evidence on preconception care, management of diabetes-related complications, lifestyle counselling, recommendations on gestational weight gain, pharmacologic treatment and early postpartum management of T2DM.

Focus on Metformin: Its Role and Safety in Pregnancy and Beyond

Metformin is used worldwide in the treatment of type 2 diabetes and has been used in the treatment of diabetes in pregnancy since the 1970s. It is highly acceptable to patients due to its ease of administration, cost and adverse effect profile. It is effective in reducing macrosomia, large-for-gestational-age infants and reduces maternal weight gain. Despite its many advantages, metformin has been associated with reductions in foetal size and has been associated with an increase in infants born small-for-gestational-age in certain cohorts. In this article, we review its efficacy, adverse effects and long-term follow-up before, during and after pregnancy for both mother and infant. We also evaluate the other forms of treatment for gestational diabetes, including oral therapies, insulin therapy and emerging treatments.

Platelets and endothelial dysfunction in gestational diabetes mellitus

The prevalence of gestational diabetes mellitus (GDM) has increased in recent years, along with the higher prevalence of obesity in women of reproductive age. GDM is a pathology associated with vascular dysfunction in the fetoplacental unit. GDM-associated endothelial dysfunction alters the transfer of nutrients to the foetus affecting newborns and pregnant women. Various mechanisms for this vascular dysfunction have been proposed, of which the most studied are metabolic alterations of the vascular endothelium. However, different cell types are involved in GDM-associated endothelial dysfunction, including platelets. Platelets are small, enucleated cell fragments that actively take part in blood haemostasis and thrombus formation. Thus, they play crucial roles in pathologies coursing with endothelial dysfunction, such as atherosclerosis, cardiovascular diseases, and diabetes mellitus. Nevertheless, platelet function in GDM is understudied. Several reports show a potential relationship between platelet volume and mass with GDM; however, platelet roles and signaling mechanisms in GDM-associated endothelial dysfunction are unclear. This review summarizes the reported findings and proposes a link among altered amount, volume, mass, reactivity, and function of platelets and placenta development, resulting in fetoplacental vascular dysfunction in GDM.

The Implication of Mechanistic Approaches and the Role of the Microbiome in Polycystic Ovary Syndrome (PCOS): A Review

As a complex endocrine and metabolic condition, polycystic ovarian syndrome (PCOS) affects women's reproductive health. These common symptoms include hirsutism, hyperandrogenism, ovulatory dysfunction, irregular menstruation, and infertility. No one knows what causes it or how to stop it yet. Alterations in gut microbiota composition and disruptions in secondary bile acid production appear to play a causative role in developing PCOS. PCOS pathophysiology and phenotypes are tightly related to both enteric and vaginal bacteria. Patients with PCOS exhibit changed microbiome compositions and decreased microbial diversity. Intestinal microorganisms also alter PCOS patient phenotypes by upregulating or downregulating hormone release, gut-brain mediators, and metabolite synthesis. The human body's gut microbiota, also known as the "second genome," can interact with the environment to improve metabolic and immunological function. Inflammation is connected to PCOS and may be caused by dysbiosis in the gut microbiome. This review sheds light on the recently discovered connections between gut microbiota and insulin resistance (IR) and the potential mechanisms of PCOS. This study also describes metabolomic studies to obtain a clear view of PCOS and ways to tackle it.

Pharmacological approaches to the prevention of type 2 diabetes mellitus

About 1 in 10 adults worldwide are estimated to have diabetes mellitus. They are at risk of developing life-threatening complications resulting in reduced quality of life, increased mortality and higher healthcare costs. The ability to prevent or delay type 2 diabetes mellitus (T2DM) by modifying some of its risk factors has been hypothesized for decades. The long and often gradual time-course of increasing dysglycemia prior to diabetes diagnosis suggests that interventions during that period could be effective in preventing T2DM. In addition to lifestyle modifications, certain drugs prevent or slow development of hyperglycemia. Recently, drugs used for obesity management were shown to prevent T2DM. In this review, we discuss various pharmacotherapeutic options for preventing T2DM.

Efficacy and safety of metformin in pregnant women with polycystic ovary syndrome: a systematic review with meta-analysis of randomized and non-randomized controlled trials

OBJECTIVE

To evaluate the efficacy and safety of using metformin in pregnant women with polycystic ovarian syndrome (PCOS) and to explore the most effective and safe protocol by using a meta-analysis method.

METHODS

Medline, EMBASE, Cochrane Library, and other databases were searched for randomized controlled trials and prospective cohort studies enrolling pregnant women with PCOS on receiving metformin or placebo or nothing. Subgroup analyses were undertaken.

RESULTS

A total of 17 studies involving 2899 patients were included. Compared with control group, the use of metformin significantly reduced the incidence of preterm delivery (cumulative rate 3.86% vs 9.19%, relative risk (RR), 0.42 [95% confidence interval (CI), 0.25-0.71,]; p = .001), early miscarriage (cumulative rate 6.58% vs 18.35%, RR, 0.40 [95% CI, 0.20-0.78]; p = .007), gestational diabetes (cumulative rate 12.86% vs 22.91%, RR, 0.48 [95% CI, 0.26-0.89]; p = .02), and pre-eclampsia (cumulative rate 4.95% vs 7.72%, RR, 0.61 [95% CI, 0.40-0.93]; p = .02), the need for insulin treatment throughout pregnancy (cumulative rate 2.14% vs 5.12%, RR, 0.43 [95% CI, 0.22-0.85]; p = .01), and weight gain of pregnant women (mean difference, -2.45, [95% CI, -3.04 to -1.85]; p < .00001).

CONCLUSIONS

The use of metformin in pregnant women with PCOS can significantly reduce maternal complications. No significant difference was observed in serious maternal adverse events. The efficacy and safety of metformin are worthy of recognition.

Intensive Medical Nutrition Therapy Alone or with Added Metformin to Prevent Gestational Diabetes Mellitus among High-Risk Mexican Women: A Randomized Clinical Trial

The aim of this study was to examine the efficacy of intensive medical nutrition therapy (MNT) plus metformin in preventing gestational diabetes mellitus (GDM) among high-risk Mexican women. An open-label randomized clinical trial was conducted. Inclusion criteria were pregnant women with three or more GDM risk factors: Latino ethnic group, maternal age >35 years, body mass index >25 kg/m2, insulin resistance, and a history of previous GDM, prediabetes, a macrosomic neonate, polycystic ovarian syndrome, or a first-degree relative with type 2 diabetes. Women before 15 weeks of gestation were assigned to group 1 (n = 45): intensive MNT-plus metformin (850 mg twice/day) or group 2 (n = 45): intensive MNT without metformin. Intensive MNT included individual dietary counseling, with ≤50% of total energy from high carbohydrates. The primary outcome was the GDM incidence according to the International Association of Diabetes Pregnancy Study Groups criteria. There were no significant differences in baseline characteristics and adverse perinatal outcomes between the groups. The GDM incidence was n = 11 (24.4%) in the MNT plus metformin group versus n = 7 (15.5%) in the MNT without metformin group: p = 0.42 (RR: 1.57 [95% CI: 0.67–3.68]). There is no benefit in adding metformin to intensive MNT to prevent GDM among high-risk Mexican women. Clinical trials registration: NCT01675310.

Nutrition as Prevention Factor of Gestational Diabetes Mellitus: A Narrative Review

Gestational diabetes mellitus (GDM) is defined as a glucose tolerance disorder with onset or first recognition during pregnancy. GDM is associated with several adverse maternal and neonatal outcomes. Management to reduce the incidence of GDM could decrease the incidence of these complications. Modification of nutrition in the prevention of GDM is postulated. The vital issue in GDM prevention is the implementation of proper dietary patterns, appropriate physical activity, and a combination of diet and lifestyle modifications. However, intervention studies examining the effects of diet and lifestyle on GDM prevention are contradictory. The aim of this study was to review the scientific evidence on nutritional prevention strategies, including diet and supplementation of some substances such as probiotics, micro/macroelements, fiber, myoinositol, and vitamins that may be effective in reducing the risk of GDM. The presented article is a narrative review. This article indicates that certain nutritional factors may have some benefit in preventing GDM. However, further studies in a variety of populations and large groups of patients are needed. At present, no definitive conclusions can be drawn as to the best intervention in the prevention of GDM.

Gestational metformin administration in women with polycystic ovary syndrome: A systematic review and meta-analysis of randomized control studies

AIMS

To evaluate metformin's effects on pregnancy outcomes in women with polycystic ovary syndrome.

METHODS

A literature search was conducted using PubMed, EMBASE, Web of Science, MEDLINE, and the Cochrane Library. All randomized controlled trials comparing metformin administration during pregnancy versus placebo or blank in PCOS women were selected. The primary outcomes were the incidence of gestational diabetes mellitus (GDM), preterm delivery, and miscarriage. We combined data with the Review Manager. Bayesian meta-analysis was employed for further verification with the R software.

RESULTS

Six randomized control trial studies involving 1229 participants were included. Metformin use was associated with reduced risk of preterm delivery (Risk ratios [RR], 0.45; 95% CI, 0.25-0.80; p, 0.007) and higher larger neonatal head circumference (Mean difference (MD), 0.47; 95% CI, 0.20-0.74; p, 0.0006] but had no effect on the incidence of GDM (RR 1.87; 95% CI, 0.58-1.87; p, 0.89), miscarriage (RR, 0.85; 95% CI, 0.45-1.60; p, 0.62), pre-eclampsia (RR, 1.18; 95% CI, 0.43-3.21; p, 0.75), neonatal length (MD, 0.33; 95% CI, -0.12-0.78; p, 0.15) and birthweight (MD, 73.78; 95% CI, -52.98-200.53; p, 0.17).

CONCLUSIONS

Metformin administration in PCOS pregnancies was associated with reduced preterm delivery risk and larger neonatal head circumference.

Exercise versus Metformin to Improve Pregnancy Outcomes among Overweight Pregnant Women: A Systematic Review and Network Meta-Analysis

Being overweight is associated with pregnancy-related disorders such as gestational diabetes mellitus (GDM), hypertensive disorders of pregnancy (HDP), and excessive maternal weight gain (MWG). Exercise and metformin reduce the risk of these disorders. This network meta-analysis (NMA) aims to compare the effect of metformin and different types of exercise (aerobic, resistance and combined) on the risk of GDM, HDP, and MWG among overweight/obese pregnant women. Medline, EMBASE, Web of Science and Cochrane Library were searched from inception to June 2021. Meta-analyses and NMAs were performed. Sixteen randomized controlled trials were included. In the NMA, aerobic exercise showed an effect on GDM (RR = 0.51, 95% CI = 0.26, 0.97), and metformin a reduction in MWG (MWG = -2.93 kg, 95% CI = -4.98, -0.87). No intervention showed any effect on the reduction of HDP. Our study suggests that aerobic exercise may have the greatest effect in reducing the risk of GDM, and perhaps, the MWG. Strategies should be developed to increase adherence to this type of intervention among overweight women without contraindications. Although metformin could reduce MWG, medicalization of pregnancy in healthy women is not justified with the present results. More research is needed on the effect of the intensity and frequency of exercise sessions and the length of interventions.

Polycystic ovary syndrome and infertility: an update

Polycystic ovarian syndrome is the most well-known endocrine condition among women of this generation (PCOS). Symptoms of hyperandrogenism, irregular menstrual periods, and insulin resistance are all traits associated with PCOS. In women with PCOS, the chance of having problems including infertility, insulin resistance, and type 2 diabetes increases. The PCOS board hopes to reduce body weight and insulin levels, restore fertility, control excessive hair growth on the body or scalp, re-establish the regular feminine cycle, and avoid misunderstandings. Insulin sensitizers have been one of the most common metabolic modulators, but their effectiveness has been sporadic. Insulin resistance, followed by thiazolidinediones, is central to the pathophysiology of PCOS, with metformin having nearly similar efficacy. In the management of PCOS, statins and incretins are newer therapies with obvious metabolic targets. Vitamin D, acarbose, and myoinositol are just a few of the reciprocal and optional clinical treatments that have been proved to be useful in the treatment of PCOS. The number of viable methods for dealing with PCOS-related infertility has increased as well. Despite the fact that clomiphene citrate (CC) has long been the gold standard for ovulation induction in the event of ovulatory infertility, aromatase inhibitors can induce ovulation with results that are nearly identical to or better than those reported with CC, aromatase inhibitors can cause ovulation with results that are nearly identical to or better than those reported with CC. Ovarian incitement conventions that intelligently utilize gonadotropins, gonadotropin-delivering hormone rivals, the approach of ovarian boring, and assisted conceptive advancements with in vitro oocyte development indicate an expanding level of therapeutic progress.

Effects of metformin treatment on pregnancy outcomes in patients with polycystic ovary syndrome

INTRODUCTION

This review covers the current evidence regarding the use of metformin as a therapeutic intervention for optimizing pregnancy outcomes in women with polycystic ovary syndrome (PCOS).

AREAS COVERED

After searching Medline, Embase and CINAHL, all important large clinical trials and observational studies plus systematic reviews, meta-analyses and Cochrane reviews have been summarized here. The results have been compared to culminate in a thorough review and discussion on the use of metformin in relation to reproductive outcomes for women with PCOS. The role of metformin in PCOS is explored both in terms of achieving conception and during pregnancy. The existing evidence around metformin use is summarized both during the preconceptual period and during pregnancy, in relation to reproductive outcomes.

EXPERT OPINION

Metformin is a widely used medication, often prescribed to improve reproductive outcomes for women with PCOS. However, the evidence remains equivocal regarding its efficacy both in optimizing fertility and pregnancy outcomes. More research is required with special emphasis on metformin use within different populations, including ethnic groups and women with varying BMI ranges.

Are morphokinetic parameters of embryo development associated with adverse perinatal outcomes following fresh blastocyst transfer?

RESEARCH QUESTION

Are obstetric and perinatal complications associated with morphokinetic parameters of embryo development?

DESIGN

This proof-of-concept pilot study included a retrospective analysis of embryo morphokinetic parameters of 85 live births following day 5 single blastocyst transfer. Kinetic variables included time interval (hours) from time of pronuclei fading (tPNf) to: time of 2 cells (tPNf-t2), 9 cells (tPNf-t9), morula (tPNf-tM), start of blastulation (tPNf-tSB), full blastocyst (tPNf-tB) and expanded blastocyst (tPNf-tEB). Multivariable logistic models were used to calculate the risk of perinatal complications after adjustment for confounders.

RESULTS

The mean interval of tPNf-tSB was significantly longer for newborns with congenital anomalies compared with healthy newborns (79.49 ± 5.78 versus 71.7 ± 6.3, respectively, P = 0.01) and for embryos of women who had gestational diabetes mellitus compared with normoglycemic women (76.56 ± 7.55 versus 71.5 ± 6.13, respectively, P = 0.015). The mean interval of tPNf-t9 was significantly longer for low-birthweight newborns compared with normal weight (49.25 ± 5.54 versus 45.47 ± 4.77, respectively, P = 0.01). Preterm delivery was associated with several longer intervals of cell divisions compared with delivery at term (tPNf-t5: 28.76 ± 3.13 versus 26.64 ± 2.40, respectively, P = 0.01; tPNf-t6: 30.10 ± 3.05 versus 27.68 ± 2.30, respectively, P < 0.001; tPNf-t7: 32.08 ± 4.11 versus 28.70 ± 2.67, respectively, P < 0.001; tPNf-t8: 34.75 ± 4.95 versus 30.70 ± 4.10, respectively, P < 0.001; tPNf-t9: 50.23 ± 5.87 versus 45.44 ± 4.67, respectively, P < 0.001). For each of the outcomes, the association remained significant after adjusting for confounders.

CONCLUSION

This study indicates that there may be a possible association between adverse perinatal outcomes and morphokinetic parameters. Larger studies are needed to establish this association.

Cost-effectiveness analysis of polycystic ovary syndrome management and the risk of gestational diabetes in pregnant women: a decision-tree model

BACKGROUND

This study estimated the cost-effectiveness of metformin to reduce the risk of gestational diabetes mellitus (GDM) in pregnant women with polycystic ovary syndrome (PCOS) from the US health-care payer perspective.

METHODS

A decision tree was developed to simulate the progression of PCOS in a hypothetical cohort of 10,000 pregnant women diagnosed with PCOS and two scenarios were tested. Normal glucose regulation without developing GDM, average cost-effectiveness ratios (ACER), and the incremental cost-effectiveness ratios (ICERs) were the outcome measures assessed through pregnancy. Evidence from randomized clinical trials and other published literature were used to assess disease progression and its associated health-care costs. Sensitivity analyses that varied key model parameters were conducted.

RESULTS

Management of PCOS with metformin was associated with lowest ACER ($669.78 per normal glucose regulation without GDM) as compared to 'no intervention' strategy. Metformin use is the most cost-effective strategy to manage PCOS during pregnancy with average cost savings of $7,593,372.97 and an average effect gain of 2271 of normal glucose regulation without GDM among pregnant women with PCOS. Sensitivity analyses determined that the results are robust.

CONCLUSIONS

Management of PCOS during pregnancy may be a cost-effective strategy to reduce GDM risk and its associated complications.

Metformin in colorectal cancer: molecular mechanism, preclinical and clinical aspects

Growing evidence showed the increased prevalence of cancer incidents, particularly colorectal cancer, among type 2 diabetic mellitus patients. Antidiabetic medications such as, insulin, sulfonylureas, dipeptyl peptidase (DPP) 4 inhibitors and glucose-dependent insulinotropic peptide (GLP-1) analogues increased the additional risk of different cancers to diabetic patients. Conversely, metformin has drawn attention among physicians and researchers since its use as antidiabetic drug exhibited beneficial effect in the prevention and treatment of cancer in diabetic patients as well as an independent anticancer drug. This review aims to provide the comprehensive information on the use of metformin at preclinical and clinical stages among colorectal cancer patients. We highlight the efficacy of metformin as an anti-proliferative, chemopreventive, apoptosis inducing agent, adjuvant, and radio-chemosensitizer in various colorectal cancer models. This multifarious effects of metformin is largely attributed to its capability in modulating upstream and downstream molecular targets involved in apoptosis, autophagy, cell cycle, oxidative stress, inflammation, metabolic homeostasis, and epigenetic regulation. Moreover, the review highlights metformin intake and colorectal cancer risk based on different clinical and epidemiologic results from different gender and specific population background among diabetic and non-diabetic patients. The improved understanding of metformin as a potential chemotherapeutic drug or as neo-adjuvant will provide better information for it to be used globally as an affordable, well-tolerated, and effective anticancer agent for colorectal cancer.

Metformin attenuates susceptibility to inflammation-induced preterm birth in mice with higher endocannabinoid levels

Premature decidual senescence is a contributing factor to preterm birth. Fatty acid amide hydrolase mutant females (Faah-/-) with higher endocannabinoid levels are also more susceptible to preterm birth upon lipopolysaccharide (LPS) challenge due to enhanced decidual senescence; this is associated with mitogen-activated protein kinase p38 activation. Previous studies have shown that mechanistic target of rapamycin complex 1 (mTORC1) contributes to decidual senescence and promotes the incidence of preterm birth. In this study, we sought to attenuate premature decidual aging in Faah-/- females by targeting mTORC1 and p38 signaling pathways. Because metformin is known to inhibit mTOR and p38 signaling pathways, Faah-/- females were treated with metformin. These mice had a significantly lower preterm birth incidence with a higher rate of live birth after an LPS challenge on day 16 of pregnancy; metformin treatment did not affect placentation or neonatal birth weight. These results were associated with decreased levels of p38, as well as pS6, a downstream mediator of mTORC1 activity, in day 16 Faah-/-decidual tissues. Since metformin treatment attenuates premature decidual senescence with limited side effects during pregnancy, careful use of this drug may be effective in ameliorating specific adverse pregnancy events.

Afamin predicts gestational diabetes in polycystic ovary syndrome patients preconceptionally

BACKGROUND

Patients suffering from polycystic ovary syndrome (PCOS) are often insulin resistant and at elevated risk for developing gestational diabetes mellitus (GDM). The aim of this study was to explore afamin, which can be determined preconceptionally to indicate patients who will subsequently develop GDM. Serum concentrations of afamin are altered in conditions of oxidative stress like insulin resistance (IR) and correlate with the gold standard of IR determination, the HOMA index.

METHODS

Afamin serum concentrations and the HOMA index were analyzed post hoc in 63 PCOS patients with live births. Patients were treated at Essen University Hospital, Germany, between 2009 and 2018. Mann-Whitney U test, T test, Spearman's correlation, linear regression models and receiver-operating characteristic (ROC) analyses were performed for statistical analysis.

RESULTS

Patients who developed GDM showed significantly higher HOMA and serum afamin values before their pregnancy (P < 0.001, respectively). ROCs for afamin concentrations showed an area under the curve of 0.78 (95% confidence interval (CI) 0.65-0.90) and of 0.77 (95% CI 0.64-0.89) for the HOMA index. An afamin threshold of 88.6 mg/L distinguished between women who will develop GDM and those who will not with a sensitivity of 79.3% and a specificity of 79.4%. A HOMA index of 2.5 showed a sensitivity of 65.5% and a specificity of 88.2%.

CONCLUSION

The HOMA index and its surrogate parameter afamin are able to identify pre-pregnant PCOS patients who are at risk to develop GDM. Serum afamin concentrations are independent of fasting status and therefore an easily determinable biomarker.

Low Protein Diets for Pregnant Women and Its Association with Insulin Secretion and Resistance

Gestational diabetes mellitus (GDM) complicates 3.5% of pregnancies in England and Wales and continues to show an increase in incidence each year. GDM can lead to diabetes postpartum, it is associated with an increased perinatal risk, and an increase in neonatal mortality. This review article looks at different studies regarding protein diets and their potential effects on GDM. We aimed to determine if a certain protein diet could potentially help protect against GDM using. We found that while a few studies have shown that increasing proteins in the diet of pregnant women, specifically that from poultry, whey, fish, nuts and legumes, may reduce the risk of GDM, there is certainly room for further research on the topic.

Metformin therapy before conception versus throughout the pregnancy and risk of gestational diabetes mellitus in women with polycystic ovary syndrome: a systemic review, meta-analysis and meta-regression

The results of studies that assessed the impact of metformin treatments on gestational diabetes mellitus (GDM) in patients with polycystic ovary syndrome (PCOS) are inconclusive. In addition, the impact of time and duration of metformin therapy for an optimum reduction of GDM has not been reported in these studies. This study aimed to summarize current knowledge regarding the effect of metformin-therapy before conception versus throughout pregnancy on the risk of GDM in women with PCOS. PubMed, Scopus, Google Scholar and ScienceDirect databases were searched to identify relevant studies. Both fixed and random effect models were used. Subgroup analyses were performed based on the on the study methodology. The association between the PCOS status and GDM was assessed using the univariate and multiple meta-regression analysis adjusted by the BMI and metformin therapy. Forty-eight of 1397 identified studies were included involving 5711 PCOS patients and 20,296 controls. Regardless of metformin therapy, the prevalence of GDM diagnosed in the second trimester among women with PCOS was significantly higher than healthy controls that was independent of obesity. Including all studies, the increased risk of GDM among women with PCOS, compared to healthy controls, disappeared after the adjustment of metformin-therapy (β = 0.08, 95% CI 0.04, 0.2; p = 0.624). By excluding observational studies as a source of bias, the prevalence of GDM among women with PCOS treated using metformin before conception till the end of pregnancy did not differ from treated just before conception (β = - 0.09, 95% CI - 0.2, 0.02; p = 0.092) or those without metformin therapy (β = - 0.05, 95% CI - 0.07, 0.04; p = 0.301). The results remained unchanged after the subgroup analysis based on the methodology of RCTs and non-RCTs studies. The main body of literature in the current meta-analysis was observational, which may be mixed with some sources of bias. Also, a lack of well-designed and high quality interventional studies means that the findings should be interpreted with cautious. In this respect, decisions regarding the continuation or discontinuation of metformin therapy in women with PCOS are somewhat arbitrary and can be made individually based on the patient's condition given the presence or absence of other GDM risk factors. Additional well-designed RCTs still need for precise recommendation.

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 Use in PCOS Pregnancies Increases the Risk of Offspring Overweight at 4 Years of Age: Follow-Up of Two RCTs

CONTEXT

Metformin is used in pregnancy in women with gestational diabetes mellitus, polycystic ovary syndrome (PCOS), and obesity. Metformin passes the placenta.

OBJECTIVE

To explore the effects of metformin use in PCOS pregnancies on offspring growth to 4 years of age.

DESIGN

Follow-up study of two randomized, double-blind, placebo-controlled trials.

SETTING

Secondary care centers. Eleven public hospitals in Norway.

PARTICIPANTS

One hundred eighty-two children of mothers with PCOS who participated in two randomized controlled trials.

INTERVENTION

Metformin 1700 or 2000 mg/d or placebo from first trimester to delivery in the original studies. No intervention in the current study.

MAIN OUTCOME MEASURES

Height, weight, body mass index (BMI), and overweight/obesity at 4 years of age and head circumference at 1 year of age, converted to z scores.

RESULTS

The difference in height z score means between the groups at 4 years of age was nonsignificant (0.07 [95% confidence interval (CI): -0.22 to 0.36]; P = 0.651). At 4 years of age, the metformin group had higher weight z score than the placebo group [difference in means: 0.38 (0.07 to 0.69); P = 0.017] and higher BMI z score [difference in means: 0.45 (0.11 to 0.78); P = 0.010]. There were more overweight/obese children in the metformin group [26 (32%)] than in the placebo group [14 (18%)] at 4 years of age [odds ratio: 2.17 (1.04 to 4.61); P = 0.038]. The difference in mean head circumference z score at 1 year of age was 0.27 (-0.04 to 0.58; P = 0.093).

CONCLUSION

Metformin-exposed children had higher BMI and increased prevalence of overweight/obesity at 4 years of age.

The diversity of gestational diabetes: a therapeutic challenge

Metformin as the first drug of choice for glucose lowering in gestational diabetes (GDM) is still controversial, despite recent publications reporting similar outcomes in comparison to insulin, both for offspring and mothers. The use of metformin during pregnancy is increasing and several recent guidelines recommend metformin use in GDM pregnancies. Background, current metformin use and unresolved concerns are discussed in the context of the article from Gante and coworkers.

Therapeutic approach for metabolic disorders and infertility in women with PCOS

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder affecting 5-10% of women of reproductive age. It generally shows with oligo/amenorrhea, anovulatory cycles, clinical o biochemical hirsutism, polycystic ovaries and, in a significant percentage of cases, insulin resistance. PCOS is defined as a multifactorial pathology, determined by the association of many factors: genetic, endocrine and environmental. The first and most effective treatment of PCOS is to change life-style and lose weight. The use of oral contraceptives has been shown effective in reducing acne and hirsutism and regulates the menstrual cycle. For women with severe hirsutism, the addition of antiandrogens to estrogen-progestin therapy has significantly improved the results. In cases of anovulatory infertility, the drug of first choice is clomiphene citrate, followed by low-dose gonadotropins. Recently, insulin-sensitizing drugs have been widely prescribed for PCOS patients. They are particularly effective in reducing insulin resistance and improving ovulatory performance. Besides insulin-sensitizing drugs, natural substances, such as inositol, seems to have good efficacy, similar to metformin with fewer side effects. New substances that could be used include statins and natural statins, such as monakolin, alone or combined with myo-inositol. These substances do not have side effects and greatly reduce the hyperandrogenic component in these patients.

Metformin as a prophylactic treatment of gestational diabetes in pregnant patients with pregestational insulin resistance: A randomized study

AIM

We aimed to assess the use of metformin (MTF) in the prevention of gestational diabetes mellitus (GDM) in patients with pregestational insulin resistance (PIR).

METHODS

A double blind, multicenter, randomized trial was carried out in patients with a history of PIR and pregestational MTF treatment. Groups were allocated either to MTF 1700 mg/day or placebo. Patients were recruited between 12⁺⁰ and 15⁺⁶  gestational weeks, and treatment was extended until week 36. A multiple logistic regression analysis was applied to determine the relation between the use of metformin and the development of GDM.

RESULTS

One hundred and forty one patients were randomized (68 patients in the MTF group and 73 in the placebo group). A total of 30 patients withdrew from the study during follow-up. Administration of MTF was not associated with a decrease in the incidence of GDM as compared to placebo (37.5% vs 25.4%, respectively; P = 0.2). Moreover, MTF administration was associated with a significant increase in drug intolerance as compared to placebo (14.3% vs 1.8%, respectively; P = 0.02).

CONCLUSION

The use of MTF is not effective in prevention of GDM in populations with PIR. The use of MTF shows a significantly higher frequency of drug intolerance than placebo.

Metformin, the aspirin of the 21st century: its role in gestational diabetes mellitus, prevention of preeclampsia and cancer, and the promotion of longevity

Metformin is everywhere. Originally introduced in clinical practice as an antidiabetic agent, its role as a therapeutic agent is expanding to include treatment of prediabetes mellitus, gestational diabetes mellitus, and polycystic ovarian disease; more recently, experimental studies and observations in randomized clinical trials suggest that metformin could have a place in the treatment or prevention of preeclampsia. This article provides a brief overview of the history of metformin in the treatment of diabetes mellitus and reviews the results of metaanalyses of metformin in gestational diabetes mellitus as well as the treatment of obese, non-diabetic, pregnant women to prevent macrosomia. We highlight the results of a randomized clinical trial in which metformin administration in early pregnancy did not reduce the frequency of large-for-gestational-age infants (the primary endpoint) but did decrease the frequency of preeclampsia (a secondary endpoint). The mechanisms by which metformin may prevent preeclampsia include a reduction in the production of antiangiogenic factors (soluble vascular endothelial growth factor receptor-1 and soluble endoglin) and the improvement of endothelial dysfunction, probably through an effect on the mitochondria. Another potential mechanism whereby metformin may play a role in the prevention of preeclampsia is its ability to modify cellular homeostasis and energy disposition, mediated by rapamycin, a mechanistic target. Metformin has a molecular weight of 129 Daltons and therefore readily crosses the placenta. There is considerable evidence to suggest that this agent is safe during pregnancy. New literature on the role of metformin as a chemotherapeutic adjuvant in the prevention of cancer and in prolonging life and protecting against aging is reviewed briefly. Herein, we discuss the mechanisms of action and potential benefits of metformin.

Association of polycystic ovary syndrome with metabolic syndrome and gestational diabetes: Aggravated complication of pregnancy

Polycystic ovary syndrome (PCOS) affects 5–20% of the reproductive age women globally. PCOS is diagnosed by the presence of hyperandrogenism, oligo-anovulation, and polycystic morphology of at least one ovary. Insulin resistance (IR), hyperinsulinemia and associated metabolic abnormalities including metabolic syndrome play a significant role in the development of PCOS. The chances of developing MS in PCOS women was shown to increase by almost 14-fold in patients with increasing body mass index. Even in the absence of overt obesity, a preferential deposition of intra-abdominal fat is noted in PCOS women and this intra-abdominal fat leads to impaired insulin action and functional IR and hyperandrogenism. Functional ovarian hyperandrogenism of ovaries was suggested to be a consequence of IR, which activates androgen synthesizing enzyme, cytochrome p450-c17α-hydroxylase, in ovarian theca cells and causes elevated oxidative stress accompanied by lower antioxidant status in ovaries, which contribute to PCOS pathogenesis. The elevated levels of luteinizing hormone that accompany the early stages of hyperandrogenemia, accelerate ovarian functional deterioration, which is further aggravated by hyperinsulinemia, in PCOS women. The risk of developing gestational diabetes in PCOS women is approximately three times greater, as compared to non-PCOS women, due to IR and hyperinsulinemia. Typical insulin-sensitizing drugs such as metformin, have been used to curtail IR and hyperinsulinemia in pregnant PCOS women, with varying results indicating the complexity of the disease and the need for better controlled studies and additional efforts for PCOS-specific drug discovery.

Maternal nutrition: opportunities in the prevention of gestational diabetes

Gestational diabetes mellitus (GDM) is currently defined as glucose intolerance that is of variable severity with onset or first recognition during pregnancy. The Hyperglycemia and Adverse Pregnancy Outcome Study, including 25 000 nondiabetic pregnant women in 15 centers across the world, reported that an average of 17.8% of pregnancies are affected by GDM and its frequency can be as high as 25.5% in some countries, based on the International Association of Diabetes and Pregnancy Study Groups criteria. Nevertheless, true global prevalence estimates of GDM are currently lacking due to the high level of heterogeneity in screening approaches, diagnostic criteria, and differences in the characteristics of the populations that were studied. The presence of systemic high blood glucose levels in pregnancy results in an adverse intrauterine environment, which has been shown to have a negative impact on short- and long-term health outcomes for both the mother and her offspring, including increased risks for the infant to develop obesity and for both mother and child to develop type 2 diabetes mellitus later in life. Epigenetic mechanisms that are directly influenced by environmental factors, including nutrition, may play a key role in shaping these future health risks and may be part of this vicious cycle. This article reviews the burden of GDM and the current evidence that supports maternal nutritional interventions as a promising strategy to break the cycle by addressing risk factors associated with GDM.

Oral Antidiabetic Agents in Pregnancy and Lactation: A Paradigm Shift?

Objective:

To provide information on the use of oral antidiabetic agents in pregnancy and breast-feeding.

Data Sources:

Primary articles were identified by a MEDLINE search (1966–March 2007) using the MeSH headings: pregnancy in diabetics, pregnancy, polycystic ovary syndrome, hypoglycemic agents, glipizide, glyburide, metformin, rosiglitazone, pioglitazone, clinical trial, controlled clinical trial, multicenter study, randomized controlled trial, case–control studies, and cohort studies.

Study Selection and Data Extraction:

All studies using oral antidiabetic agents in pregnancy were evaluated and relevant data were included in the discussion.

Data Synthesis:

Studies of glyburide and glipizide have found little or no transfer of these drugs across the placenta, whereas metformin and rosiglitazone cross readily. Animal studies have found no evidence to suggest that glyburide, glipizide, metformin, or rosiglitazone are teratogenic. In gestational diabetes, glyburide was safe and efficacious; however, 16–19% of women failed to achieve optimal glucose control. No developmental toxicity in infants was observed when metformin was used before and throughout pregnancy in women with polycystic ovarian syndrome (PCOS). Some of the studies involving patients with type 2 diabetes had methodological problems. A randomized controlled trial using metformin for gestational diabetes in the third trimester is underway. The human information is inadequate to evaluate the risk of glipizide or the thiazolidinediones in pregnancy. In breast milk, 3 studies measured nonsignificant amounts of metformin and one study was unable to detect either glyburide or glipizide.

Conclusions:

Neither glyburide nor metformin has caused developmental toxicity in humans. Glyburide has been used for the treatment of gestational diabetes, and metformin has been used in women with PCOS who eventually became pregnant. Additional trials are needed to better define the benefits and risks of oral antidiabetic agents in pregnancy. Metformin, glyburide, and glipizide appear to be compatible with breast-feeding.

Effects of metformin on pregnancy outcomes in women with polycystic ovary syndrome: A meta-analysis

AIM

The aim of the study is to evaluate the effects of metformin on pregnancy outcomes in women with polycystic ovary syndrome (PCOS).

METHODS

We searched electronic databases and bibliographies of relevant papers to identify studies comparing the pregnancy outcomes in the metformin group with those in the placebo or blank control group. Then, we did this meta-analysis based on the PRISMA guidelines. The primary outcomes included early pregnancy loss (EPL), preterm delivery, term delivery, and gestational diabetes mellitus (GDM). Secondary outcomes included pregnancy-induced hypertension (PIH), intrauterine growth restriction (IUGR), fetal malformation, vaginal delivery (VD), cesarean section (CS), and metformin's side effects, such as nausea or gastrointestinal discomfort. Certainly, data about neonatal death and macrosomia were analyzed if data available.

RESULTS

Finally, 13 studies including 5 randomized controlled trials (RCT) and 8 cohort studies involving 1606 pregnant women with PCOS were analyzed. The pooled OR of EPL was 0.19 with obvious statistical significance, manifesting that metformin help to lower the rate of EPL (95% CI 0.12-0.28, P < 0.00001). Simultaneously, metformin showed the advantage of reducing the prevalence of preterm delivery (OR 0.37, 95% CI 0.20-0.68, P = 0.002). In addition, metformin could promote term delivery greatly and the pooled OR was 5.23 with sharp statistical difference (95% CI 3.12-8.75, P < 0.00001).

CONCLUSION

Metformin treatment in women with PCOS throughout pregnancy could increase the possibility of term delivery, VD and reduce the risk of EPL, preterm labor, pregnancy complications such as GDM and PIH, with no serious side effects. Moreover, metformin was not teratogenic based on the limited data. So we may recommend metformin treatment for women with PCOS during the whole pregnancy period for it is quite beneficial and safe for both mothers and babies.

Pregnancy Loss, Polycystic Ovary Syndrome, Thrombophilia, Hypofibrinolysis, Enoxaparin, Metformin

Thrombophilia, hypofibrinolysis, and polycystic ovary syndrome (PCOS) are associated with recurrent pregnancy loss (RPL) and spontaneous abortion (SAB) alone and concurrently. The efficacy and safety of combined enoxaparin-metformin was prospectively assessed in women with PCOS with one or more previous SAB, thrombophilia, and/or hypofibrinolysis. Twenty-four white women with PCOS were studied; 23 with previous pregnancies, seven with RPL of unknown etiology (≥ three consecutive pregnancy losses <20 weeks’ gestation), two with two consecutive SABs, 13 with one SAB, and one with one live birth (HELLP syndrome). Prospectively, metformin (1.5 to 2.55 g/day) was administered before and throughout gestation, with concurrent enoxaparin (60 mg/day) throughout gestation. The 24 cases differed from 93 normal white female controls for the factor V Leiden mutation, 17% vs. 2%, Fisher’s p [pf] = .016, and for the 4G4G mutation of the plasminogen activator inhibitor-1 (PAI-1) gene (46% vs. 24%, Chi-square 4.63, p =. 031). The patients also differed from 44 normal white female controls for high levels (> 21.1 U/mL) of the PAI-1 gene product, plasminogen activator inhibitor activity (PAI-Fx) (33% vs. 8%, pf =. 018), and for high factor VIII (>150%) (22% vs. 0%, pf = .037). Of the 24 women, 23 had 65 previous pregnancies without metformin or enoxaparin, with 18 live births, 46 SAB (71%), and one elective abortion. On metforminenoxaparin, the same 23 women had 26 current pregnancies (28 fetuses), with 20 live births, two normal pregnancies 13 weeks or longer, and six SAB (21%), 3.4-fold lower than previous gestations (McNemar’s S = 33.6, p <. 0001). There were no adverse maternal or fetal therapy effects. Enoxaparin-metformin reduces pregnancy loss in women with PCOS with one or more previous SAB, who also have thrombophilia and/or hypofibrinolysis.

Prevention of gestational diabetes mellitus: Where are we now?

Gestational diabetes mellitus (GDM) is increasing at a rapid rate, driven by the increasing proportion of the population that is overweight/obese from a young age. More than 25 randomized controlled trials testing whether GDM can be prevented have now reported their findings, but only four different interventions have shown a reduction in the proportion of women with GDM (healthy eating alone, healthy eating with physical activity, myoinositol supplementation and probiotic treatment), and these results have not been replicated. The interventions tested to date include different diets and different forms of physical activity, in combination or alone, vitamin D, myoinositol, probiotics and metformin. Studies could be improved by using the International Association of Diabetes and Pregnancy Study Group criteria for GDM (which are probably more sensitive to change because of their multiple time points), targeting and tailoring interventions to subgroups most likely to benefit, and separating those with GDM early in pregnancy from those developing GDM de novo. The greatest societal benefit is likely to arise from population-based lifestyle approaches which include those women yet to become pregnant and those who are already pregnant and their families; an approach that is yet to be fully tested.

First-trimester exposure to metformin and risk of birth defects: a systematic review and meta-analysis

BACKGROUND

Metformin is generally considered a non-teratogenic drug; however, only a few studies specifically designed to assess the rate of congenital anomalies after metformin use have been published in the literature. The objects of the present study were to review all of the prospective and retrospective studies reporting on women treated with metformin at least during the first trimester of their pregnancy and to estimate the overall rate of major birth defects.

METHODS

Databases were searched for English language articles until December 2013. Inclusion criteria for the meta-analysis were: a case group of women with PCOS or pre-pregnancy type 2 diabetes and first-trimester exposure to metformin; a disease-matched control group which was not exposed to metformin or other oral anti-diabetic agents; and a list of the major anomalies in both the study and the control groups. A random effects model was used for the meta-analysis of data, using odds ratios. Studies not fulfilling the inclusion criteria for the meta-analysis but reporting relevant data on major malformations in women diagnosed with PCOS were then used to estimate the overall birth defects rate.

RESULTS

Meta-analysis of nine controlled studies with women affected by PCOS detected that the rate of major birth defects in the metformin-exposed group was not statistically increased compared with the disease-matched control group and that there was no significant heterogeneity among the studies. The metformin-exposed sample was composed of 351 pregnancies and the OR of major birth defects was 0.86 (95% confidence interval: 0.18-4.08; Pheterogeneity = 0.71). By evaluating all of the non-overlapping PCOS studies reported in the literature, even those without an appropriate control group, the overall rate of major anomalies was 0.6% in the sample of 517 women who discontinued the therapy upon conception or confirmation of pregnancy and 0.5% in the sample of 634 women who were treated with metformin throughout the first trimester of their pregnancy. Regarding type 2 diabetic women, we did not identify a sufficient number of studies with metformin exposure during the first trimester to proceed with the meta-analysis.

CONCLUSIONS

There is currently no evidence that metformin is associated with an increased risk of major birth defects in women affected by PCOS and treated during the first trimester. However larger ad hoc studies are warranted in order to definitely confirm the safety and efficacy of this drug in pregnancy.

Effect of metformin intervention during pregnancy on the gestational diabetes mellitus in women with polycystic ovary syndrome: a systematic review and meta-analysis

Metformin is an effective insulin sensitizer treating type 2 diabetes mellitus. However, the functional consequences of metformin administration throughout pregnancy on gestational diabetes mellitus (GDM) with polycystic ovary syndrome (PCOS) have not been assessed. We therefore performed a meta-analysis and system review to determine the effect of metformin on GDM in PCOS. A meta-analysis was performed on the published studies before December, 2013. Meta-analysis examined whether metformin could reduce GDM occurrence in PCOS with a fixed effect model. The odds ratio (OR) with 95% confidence interval (95% CI) was calculated to estimate the strength of association. A total of 13 studies including 5 RCTs and 8 non-RCTs were enrolled. Ultimately, effectiveness analysis demonstrated that, in total, there was no significant availability of metformin on GDM in PCOS in contrast to placebo (OR = 1.07, 95% CI 0.60-1.92) in RCTs and significant availability of metformin on GDM (OR = 0.19, 95% CI 0.13-0.27) was indicated in non-RCTs. In summary, according to the results of our meta-analysis, strictly, metformin did not significantly effect on GDM with PCOS, though more multicenters RCTs still need to be investigated.

Midpregnancy Doppler ultrasound of the uterine artery in metformin- versus placebo-treated PCOS women: a randomized trial

CONTEXT

Metformin is used to reduce pregnancy complications in women with polycystic ovary syndrome (PCOS), although it is not approved for this indication and solid evidence is lacking. Midpregnancy Doppler ultrasound is one of the best methods for prediction of adverse pregnancy outcome.

OBJECTIVE

The objectives of the study were to investigate the following: 1) whether metformin treatment influenced the midpregnancy pulsatility index (PI) of the uterine artery; 2) whether metabolic or endocrine factors affect the PI of the uterine artery of PCOS women; and 3) whether PI predicted adverse pregnancy outcome in PCOS woman.

DESIGN

This is a substudy of a randomized, placebo-controlled, double-blind, multicenter study conducted at 11 secondary care centers. We randomly assigned 273 pregnancies to receive metformin or placebo, from the first trimester of pregnancy to delivery. In the present substudy, 231 pregnancies are included, ie, those who completed the ultrasound examinations.

MAIN OUTCOME MEASURES

Midpregnancy PI in the uterine artery related to metformin use, androgen levels, an oral glucose tolerance test, and insulin levels was measured. We found no difference in the PI between the metformin and placebo groups. In multivariate analyses, fasting serum glucose of the first and second trimester correlated positively to the midpregnancy PI. Only in univariate analyses a weak correlation between androstenedione and PI was seen.

CONCLUSIONS

Metformin treatment did not affect uterine artery blood flow, measured by PI. High fasting blood glucose correlated inversely to uterine artery blood flow. The midpregnancy PI correlated positively to preeclampsia, hypertension, and gestational diabetes mellitus in PCOS pregnancies. Androgen levels correlated only to PI in univariate analyses.

[Polycystic ovary syndrome: what are the obstetrical risks?]

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age and the leading cause of female infertility. This condition is frequently associated with significant metabolic disorders, including obesity and hyperinsulinemia. Therefore, it seems essential to focus on the pregnancy of these patients and possible obstetric complications. Many studies suggest an increase in the risk of obstetric pathology: early miscarriage, gestational hypertension, preeclampsia, gestational diabetes mellitus diagnosed during early pregnancy, prematurity, low birthweight or macrosomia, neonatal complications and cesarean sections. However, it is difficult to conclude clearly about it, because of the heterogeneity of definition of PCOS in different studies. In addition, many confounding factors inherent in PCOS including obesity are not always taken into account and generate a problem of interpretation. However it seems possible to conclude that PCOS does not increase the risk of placental abruption, HELLP syndrome, liver disease, postpartum hemorrhage, late miscarriage and stillbirth.

Diabetes and the female reproductive system

The insulin/insulin-like growth factor (IGF) pathways and glucose metabolism act as mediators of human ovarian function and female fertility. In normal insulin action, insulin binds to its own receptors in the ovary to mediate steroidogenesis and act as a co-gonadotropin. Insulin with other factors may influence ovarian growth and cyst formation. The IGF pathway also seems to influence normal ovarian function. Insulin signaling affects reproductive function. Dysregulation of this pathway leads to altered puberty, ovulation, and fertility. Better understanding of the normal physiology and pathophysiology of insulin, IGF, and glucose effects on the human reproductive system will allow for better outcomes.

The efficacy of metformin in pregnant women with polycystic ovary syndrome: a meta-analysis of clinical trials

OBJECTIVES

The role of metformin in the treatment of pregnant women with polycystic ovary syndrome (PCOS) is controversial. Therefore, we evaluated whether the use of metformin during pregnancy in women with PCOS could reduce pregnancy-related complications.

RESEARCH DESIGN AND METHODS

MEDLINE was searched to retrieve relevant trials. In addition, reviews and reference lists of the retrieved articles were scanned for further appropriate studies. The primary outcome measure was the incidence of complications of pregnancy, which included early pregnancy loss (EPL), gestational diabetes (GDM), pre-eclampsia (PE), and pre-term delivery (PD).

RESULTS

In total, eight studies with 1106 patients were included. The pooled odds ratio (OR) (95% confidence interval) of outcome for pregnant women with PCOS prescribed metformin were 0.32 (0.19-0.55) for EPL, 0.37 (0.25-0.56) for GDM, 0.53 (0.30-0.95) for PE and 0.30 (0.13-0.68) for PD.

CONCLUSIONS

Metformin therapy throughout pregnancy decreased the OR of EPL, GDM, PE, and PD in pregnant PCOS women with no serious detrimental side effects.

Efficacy and safety of metformin during pregnancy in women with gestational diabetes mellitus or polycystic ovary syndrome: a systematic review

BACKGROUND

Metformin is an effective oral anti-hyperglycemic agent that is widely used to manage diabetes mellitus type 2 in the general population and more recently, in pregnancy. However, as metformin crosses the placenta, its use during pregnancy raises concerns regarding potential adverse effects on the mother and fetus.

OBJECTIVE

(i) To provide background for the use of metformin during pregnancy through a narrative review and (ii) to critically appraise the published evidence on the efficacy and safety of using metformin during pregnancy through a systematic review.

RESULTS

Metformin appears to be effective and safe for the treatment of gestational diabetes mellitus (GDM), particularly for overweight or obese women. However, patients with multiple risk factors for insulin resistance may not meet their treatment goals with metformin alone and may require supplementary insulin. Evidence suggests that there are potential advantages for the use of metformin over insulin in GDM with respect to maternal weight gain and neonatal outcomes. Furthermore, patients are more accepting of metformin than insulin. The use of metformin throughout pregnancy in women with polycystic ovary syndrome reduces the rates of early pregnancy loss and preterm labor and protects against fetal growth restriction. There have been no demonstrable teratogenic effects, intra-uterine deaths or developmental delays with the use of metformin.

CONCLUSIONS

The publications reviewed in this paper support the efficacy and safety of metformin during pregnancy with respect to immediate pregnancy outcomes. Because there are no guidelines for the continuous use of metformin in pregnancy, the duration of treatment is based on clinical judgment and experience on a case-by-case basis.