Physiological reduction in fasting plasma glucose concentration in the first trimester of normal pregnancy: the diabetes in early pregnancy study

Perinatal outcomes in pregnancies achieved after fertility treatments with and without diet-controlled GDM

OBJECTIVE

To evaluate the rates of adverse perinatal outcomes among women who conceived after fertility treatments with and without diet-controlled GDM.

METHODS

In this retrospective population-based cohort study, all pregnancies of non-diabetic and diet-controlled GDM women who conceived after fertility treatments (in-vitro fertilization - IVF and ovulation induction - OI) and delivered between the years 1996-2016 in a tertiary medical center, were included. Pregnancies of women with pre-gestational diabetes mellitus, and those complicated with gestational diabetes mellitus A2, multiple pregnancies, congenital malformations and those lacking prenatal care, were excluded. Demographical, clinical, and obstetrical characteristics were recorded, and pregnancy complications and adverse perinatal outcomes were compared between the groups. Multivariate logistic regression models were used to control for confounders. Statistical analyses were performed using logistic regression to control for potential confounders. A p-value of < 0.05 was considered statistically significant.

RESULTS

During the study period, 6254 deliveries met the inclusion criteria, 10.23% of them (n = 640) had diet-controlled GDM. Pregnancies with diet-controlled GDM were found to be associated with significantly higher rates of hypertensive disorders of pregnancy (15.6% vs. 9.8%, p < 0.001), polyhydramnios (5.9% vs. 2.7%, p < 0.001), and cesarean deliveries (40.8% vs. 31.9%, p < 0.001). Diet-controlled GDM was also found to be an independent protective factor against perinatal mortality (aOR = 0.22, 95% Cl 0.05-0.92, P = 0.04) possibly due to the more intensive monitoring and management typically provided to women undergoing fertility treatments. This close care may mitigate some of the risks associated with ART, leading to improved perinatal outcomes.

CONCLUSION

Among pregnancies achieved after fertility treatments, diet-controlled GDM was associated with reduced perinatal mortality and higher rates of certain pregnancy complications. These findings highlight the importance of close monitoring and careful management of women with diet-controlled GDM, as it may help mitigate risks associated with ART pregnancies. Further research is needed to understand the mechanisms behind these outcomes and to optimize management strategies for this specific population.

Characteristics and pregnancy outcomes of subtypes of gestational diabetes mellitus based on HOMA-IR and BMI

AIM

To identify the characteristics and pregnancy outcomes across different subgroups of gestational diabetes mellitus (GDM) categorized by insulin resistance index and body mass index (BMI) in early pregnancy.

METHODS

This retrospective study included 1804 women who underwent a 75 g-OGTT during 22-28 weeks of gestation, categorized into normal glucose tolerance (NGT) (1487) and GDM (317 [17.57%] of the total cohort). Metabolic parameters were assessed, and equation of homeostatic model assessment (HOMA) were utilized to compute indices of insulin resistance (HOMA-IR), β-cell secretory (HOMA-B), and insulin sensitivity (HOMA-%S) in early and mid-pregnancy. The cut-off value of HOMA-IR (1.61) in early pregnancy was determined via ROC curve analysis. This value, combined with pre-pregnancy BMI, further categorized NGT and GDM into six subgroups respectively, based on HOMA-IR levels (≥ 1.61 or < 1.61) and BMI categories (< 18.5 kg/m2, 18.5-25 kg/m2, or ≥ 25 kg/m2).

RESULTS

In comparison to women with NGT, those with GDM were notably older, had higher pre-BMI, fasting plasma glucose (FPG), insulin, and lipid levels in early pregnancy. They also exhibited more pronounced insulin resistance in both early and mid-pregnancy, leading to poorer outcomes. Following an oral glucose load, the peaks of glucose and insulin were out of sync in GDM and its subgroups, accompanied by further increases in HOMA-IR, HOMA-B, and a decrease in HOMA-%S, except for the GDM subgroup with HOMA-IR < 1.61/BMI < 18.5 kg/m2. Conversely, glucose and insulin secretion in NGT and its subgroups peaked synchronously at 60 min. GDM women with HOMA-IR ≥ 1.61/18.5 kg/m2 ≤ BMI < 25 kg/m2 had higher rates of neonatal jaundice (34.5% vs 13.9%, p < 0.0001), LGA (28.9% vs 13.2%, p = 0.001), macrosomia (9.8% vs 3.7%, p = 0.025) compared to peers, while in GDM women with HOMA-IR ≥ 1.61/BMI ≥ 25 kg/m2, the rates of LGA and macrosomia were 26.6% and 8.4%, respectively. The GDM subgroup with HOMA-IR < 1.61/BMI < 18.5 kg/m2 exhibited the highest rates of premature rupture of membrane (46.7%) and postpartum hemorrhage (20%), predominantly with vaginal delivery and a 1 min Apgar score of 4.5% in GDM women with HOMA-IR < 1.61/18.5 kg/m2 ≤ BMI < 25 kg/m2.

CONCLUSION

GDM and its subgroups displayed severe insulin resistance and poorer insulin sensitivity, leading to an increased risk of adverse pregnancy outcomes. GDM women with higher IR and normal or over weight were more likely to experience LGA and macrosomia, while those with lower IR and underweight were prone to premature rupture of membrane and postpartum hemorrhage during vaginal delivery.

Disrupted Prenatal Metabolism May Explain the Etiology of Suboptimal Neurodevelopment: A Focus on Phthalates and Micronutrients and their Relationship to Autism Spectrum Disorder

Pregnancy is a time of high metabolic coordination, as maternal metabolism adapts to support the growing fetus. Many of these changes are coordinated by the placenta, a critical fetal endocrine organ and the site of maternal-fetal crosstalk. Dysregulation in maternal and placental metabolism during pregnancy has been linked to adverse outcomes, including altered neurodevelopment. Autism spectrum disorder (ASD) is a neurodevelopmental disorder linked to metabolic alterations in both children and their mothers. Prenatal environmental exposures have been linked to risk of ASD through dysregulated maternal, placental, and fetal metabolism. In this review, we focus on recent studies investigating the associations between prenatal metabolism in the maternal-placental-fetal unit and the impact of prenatal environmental exposures to phthalates and micronutrients on ASD risk. By identifying the mechanisms through which phthalates and other ubiquitous endocrine disrupting chemicals influence development, and how nutritional interventions can impact those mechanisms, we can identify promising ways to prevent suboptimal neurodevelopment.

Continuous Glucose Monitoring Profiles in Pregnancies With and Without Gestational Diabetes Mellitus

OBJECTIVE

To determine whether continuous glucose monitoring (CGM)-derived glycemic patterns can characterize pregnancies with gestational diabetes mellitus (GDM) as diagnosed by standard oral glucose tolerance test at 24-28 weeks' gestation compared with those without GDM.

RESEARCH DESIGN AND METHODS

The analysis includes 768 individuals enrolled from two sites prior to 17 weeks' gestation between June 2020 and December 2021 in a prospective observational study. Participants wore blinded Dexcom G6 CGMs throughout gestation. Main outcome of interest was a diagnosis of GDM by oral glucose tolerance test (OGTT). Glycemic levels in participants with GDM versus without GDM were characterized using CGM-measured glycemic metrics.

RESULTS

Participants with GDM (n = 58 [8%]) had higher mean glucose (109 ± 13 vs. 100 ± 8 mg/dL [6.0 ± 0.7 vs. 5.6 ± 0.4 mmol/L], P < 0.001), greater glucose SD (23 ± 4 vs. 19 ± 3 mg/dL [1.3 ± 0.2 vs. 1.1 ± 0.2 mmol/L], P < 0.001), less time in range 63-120 mg/dL (3.5-6.7 mmol/L) (70% ± 17% vs. 84% ± 8%, P < 0.001), greater percent time >120 mg/dL (>6.7 mmol/L) (median 23% vs. 12%, P < 0.001), and greater percent time >140 mg/dL (>7.8 mmol/L) (median 7.4% vs. 2.7%, P < 0.001) than those without GDM throughout gestation prior to OGTT. Median percent time >120 mg/dL (>6.7 mmol/L) and time >140 mg/dL (>7.8 mmol/L) were higher as early as 13-14 weeks of gestation (32% vs. 14%, P < 0.001, and 5.2% vs. 2.0%, P < 0.001, respectively) and persisted during the entire study period prior to OGTT.

CONCLUSIONS

Prior to OGTT at 24-34 weeks' gestation, pregnant individuals who develop GDM have higher CGM-measured glucose levels and more hyperglycemia compared with those who do not develop GDM.

Epidemiology and management of gestational diabetes

Gestational diabetes is defined as hyperglycaemia first detected during pregnancy at glucose concentrations that are less than those of overt diabetes. Around 14% of pregnancies globally are affected by gestational diabetes; its prevalence varies with differences in risk factors and approaches to screening and diagnosis; and it is increasing in parallel with obesity and type 2 diabetes. Gestational diabetes direct costs are US$1·6 billion in the USA alone, largely due to complications including hypertensive disorders, preterm delivery, and neonatal metabolic and respiratory consequences. Between 30% and 70% of gestational diabetes is diagnosed in early pregnancy (ie, early gestational diabetes defined by hyperglycaemia before 20 weeks of gestation). Early gestational diabetes is associated with worse pregnancy outcomes compared with women diagnosed with late gestational diabetes (hyperglycaemia from 24 weeks to 28 weeks of gestation). Randomised controlled trials show benefits of treating gestational diabetes from 24 weeks to 28 weeks of gestation. The WHO 2013 recommendations for diagnosing gestational diabetes (one-step 75 gm 2-h oral glucose tolerance test at 24-28 weeks of gestation) are largely based on the Hyperglycemia and Adverse Pregnancy Outcomes Study, which confirmed the linear association between pregnancy complications and late-pregnancy maternal glycaemia: a phenomenon that has now also been shown in early pregnancy. Recently, the Treatment of Booking Gestational Diabetes Mellitus (TOBOGM) trial showed benefit in diagnosis and treatment of early gestational diabetes for women with risk factors. Given the diabesity epidemic, evidence for gestational diabetes heterogeneity by timing and subtype, and advances in technology, a life course precision medicine approach is urgently needed, using evidence-based prevention, diagnostic, and treatment strategies.

Association of serum folic acid levels in response to fasting blood glucose in early pregnancy with the risk of gestational diabetes mellitus: A retrospective cohort study

OBJECTIVE

With increasingly prevalent folic acid consumption in early pregnancy, concerns about its potentially negative effect on maternal metabolism have been raised. Recent findings regarding folic acid levels in the first trimester and the risk of gestational diabetes mellitus have been inconclusive. The aim of this study was to investigate the association of folic acid status in early pregnancy with gestational diabetes mellitus as well as examine whether glucose levels can be modulated by folic acid status during the same first trimester.

METHODS

This was a retrospective cohort study based on 27 128 Chinese pregnant women who registered during their first prenatal visit from January 2015 to December 2019. Serum folic acid and fasting blood glucose concentrations were measured during the 9th to 13th gestational weeks. Binary logistic regression was applied to estimate the odds ratios of gestational diabetes mellitus by using the serum folic acid levels quartiles with adjustment for major confounders. To investigate the potential effect of modifying key risk factors for gestational diabetes mellitus, we established subgroups, in which analyses were stratified by age (<25, 25-29, 30-34, and ≥35 y), parity (nulliparous and parous), prepregnancy body mass index (< 18.5, 18.5-23.9, and ≥ 24 kg/m2), and family history of diabetes (yes and no).

RESULTS

The positive association between maternal folate concentrations and fasting blood glucose was observed: the risk for hyperglycemia was higher in those in the middle (Q3) and higher (Q4) quartiles compared with those in Q1 and Q2. A higher risk for gestational diabetes mellitus was found in hyperglycemia of early pregnant women with high folate concentrations (Q3: odds ratio = 5.63; 95% CI, 4.56-6.95, and Q4: odds ratio = 5.57; 95% CI, 4.68-6.64) compared with normal fasting glucose mothers with folate concentrations in Q1 and Q2 after accounting for multiple covariables. Similar patterns were observed for different subgroups. Restricted cubic spline plots had a positive correlation of serum folic acid level with fasting blood glucose concentration as well as risk of gestational diabetes mellitus in a nonlinear pattern, with 32.5 nmol/L as the cutoff point for folic acid level.

CONCLUSIONS

Our findings underscore the importance of maintaining an appropriate folic acid concentration for preserving a lower risk of gestational diabetes mellitus, especially in women with relatively higher blood glucose in early pregnancy. Additionally, folic acid concentration > 32.5 nmol/L may be considered a risk factor for gestational diabetes mellitus. This research suggested that folic acid levels should be monitored during the first trimester from the first prenatal checkup to prevent adverse effects of excessive folic acid intake.

Cost-effectiveness of diagnosis and treatment of early gestational diabetes mellitus: economic evaluation of the TOBOGM study, an international multicenter randomized controlled trial

Background

A recently undertaken multicenter randomized controlled trial (RCT) "Treatment Of BOoking Gestational diabetes Mellitus" (TOBOGM: 2017-2022) found that the diagnosis and treatment of pregnant women with early gestational diabetes mellitus (GDM) improved pregnancy outcomes. Based on data from the trial, this study aimed to assess the cost-effectiveness of diagnosis and treatment of early GDM (from <20 weeks') among women with risk factors for hyperglycemia in pregnancy compared with usual care (no treatment until 24-28 weeks') from a healthcare perspective.

Methods

Participants' healthcare resource utilization data were collected from their self-reported questionnaires and hospital records, and valued using the unit costs obtained from standard Australian national sources. Costs were reported in US dollars ($) using the purchasing power parity (PPP) estimates to facilitate comparison of costs across countries. Intention-to-treat (ITT) principle was followed. Missing cost data were replaced using multiple imputations. Bootstrapping method was used to estimate the uncertainty around mean cost difference and cost-effectiveness results. Bootstrapped cost-effect pairs were used to plot the cost-effectiveness (CE) plane and cost-effectiveness acceptability curve (CEAC).

Findings

Diagnosis and treatment of early GDM was more effective and tended to be less costly, i.e., dominant (cost-saving) [-5.6% composite adverse pregnancy outcome (95% CI: -10.1%, -1.2%), -$1373 (95% CI: -$3,749, $642)] compared with usual care. Our findings were confirmed by both the CE plane (88% of the bootstrapped cost-effect pairs fall in the south-west quadrant), and CEAC (the probability of the intervention being cost-effective ranged from 84% at a willingness-to-pay (WTP) threshold value of $10,000-99% at a WTP threshold value of $100,000 per composite adverse pregnancy outcome prevented). Sub-group analyses demonstrated that diagnosis and treatment of early GDM among women in the higher glycemic range (fasting blood glucose 95-109 mg/dl [5.3-6.0 mmol/L], 1-h blood glucose ≥191 mg/dl [10.6 mmol/L] and/or 2-h blood glucose 162-199 mg/dl [9.0-11.0 mmol/L]) was more effective and less costly (dominant) [-7.8% composite adverse pregnancy outcome (95% CI: -14.6%, -0.9%), -$2795 (95% CI: -$6,638, -$533)]; the intervention was more effective and tended to be less costly [-8.9% composite adverse pregnancy outcome (95% CI: -15.1%, -2.6%), -$5548 (95% CI: -$16,740, $1547)] among women diagnosed before 14 weeks' gestation as well.

Interpretation

Our findings highlight the potential health and economic benefits from the diagnosis and treatment of early GDM among women with risk factors for hyperglycemia in pregnancy and supports its implementation. Long-term follow-up studies are recommended as a key future area of research to assess the potential long-term health benefits and economic consequences of the intervention.

Funding

National Health and Medical Research Council (grants 1104231 and 2009326), Region O¨rebro Research Committee (grants Dnr OLL-970566 and OLL-942177), Medical Scientific Fund of the Mayor of Vienna (project 15,205 and project 23,026), South Western Sydney Local Health District Academic Unit (grant 2016), and Western Sydney University Ainsworth Trust Grant (2019).

A pre-conception clinical trial to reduce intergenerational obesity and diabetes risks: The NDPP-NextGen trial protocol

BACKGROUND

Intrauterine exposure to maternal overweight/obesity or diabetes transmits risks to offspring, perpetuating a disease cycle across generations. Prenatal interventions to reduce maternal weight or dysglycemia have limited impact, while postpartum interventions can alter the intrauterine environment only if child-bearing continues. Efficacious preconception interventions are needed, especially for underserved populations, and with the potential to be scaled up sustainably. Research is also needed to assess intervention effects at conception, throughout pregnancy, and among offspring.

METHODS

This two-arm, parallel randomized clinical trial will include 360 biological females with overweight/obesity and moderate-to-high likelihood of pregnancy within 24 months. Participants will be randomized 1:1 to a yearlong pre-conception lifestyle intervention based on the National Diabetes Prevention Program (NDPP-NextGen) or usual care. Data collection will occur at enrollment (before conception), post-conception (<8 weeks gestation), late pregnancy (28-32 weeks gestation), and delivery (before discharge) for participants who become pregnant within 24 months of enrollment. Main outcomes are post-conception body mass index (<8 weeks gestation; primary outcome), post-conception fasting glucose (<8 weeks gestation; secondary outcome), and neonatal adiposity (<2 days post-birth). Additional clinical, behavioral, perinatal and offspring data will be collected, and biospecimens (blood, urine, stool, cord blood) will be banked for future ancillary studies.

CONCLUSION

This clinical trial will evaluate an intervention model (NDPP-NextGen) with potential to improve maternal health among the >50% of US females with overweight/obesity or diabetes risks in pregnancy. If successful, it can be scaled among >1800 organizations delivering NDPP in the United States to benefit the health of future generations.

Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

BACKGROUND

Numerous laboratory tests are used in the diagnosis and management of diabetes mellitus. The quality of the scientific evidence supporting the use of these assays varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for laboratory analysis in screening, diagnosis, or monitoring of diabetes. The overall quality of the evidence and the strength of the recommendations were evaluated. The draft consensus recommendations were evaluated by invited reviewers and presented for public comment. Suggestions were incorporated as deemed appropriate by the authors (see Acknowledgments). The guidelines were reviewed by the Evidence Based Laboratory Medicine Committee and the Board of Directors of the American Association for Clinical Chemistry and by the Professional Practice Committee of the American Diabetes Association.

CONTENT

Diabetes can be diagnosed by demonstrating increased concentrations of glucose in venous plasma or increased hemoglobin A1c (HbA1c) in the blood. Glycemic control is monitored by the people with diabetes measuring their own blood glucose with meters and/or with continuous interstitial glucose monitoring (CGM) devices and also by laboratory analysis of HbA1c. The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of ketones, autoantibodies, urine albumin, insulin, proinsulin, and C-peptide are addressed.

SUMMARY

The guidelines provide specific recommendations based on published data or derived from expert consensus. Several analytes are found to have minimal clinical value at the present time, and measurement of them is not recommended.

Guidelines and Recommendations for Laboratory Analysis in the Diagnosis and Management of Diabetes Mellitus

BACKGROUND

Numerous laboratory tests are used in the diagnosis and management of diabetes mellitus. The quality of the scientific evidence supporting the use of these assays varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for laboratory analysis in screening, diagnosis, or monitoring of diabetes. The overall quality of the evidence and the strength of the recommendations were evaluated. The draft consensus recommendations were evaluated by invited reviewers and presented for public comment. Suggestions were incorporated as deemed appropriate by the authors (see Acknowledgments). The guidelines were reviewed by the Evidence Based Laboratory Medicine Committee and the Board of Directors of the American Association of Clinical Chemistry and by the Professional Practice Committee of the American Diabetes Association.

CONTENT

Diabetes can be diagnosed by demonstrating increased concentrations of glucose in venous plasma or increased hemoglobin A1c (Hb A1c) in the blood. Glycemic control is monitored by the people with diabetes measuring their own blood glucose with meters and/or with continuous interstitial glucose monitoring (CGM) devices and also by laboratory analysis of Hb A1c. The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of ketones, autoantibodies, urine albumin, insulin, proinsulin, and C-peptide are addressed.

SUMMARY

The guidelines provide specific recommendations based on published data or derived from expert consensus. Several analytes are found to have minimal clinical value at the present time, and measurement of them is not recommended.

Treatment of Gestational Diabetes Mellitus Diagnosed Early in Pregnancy

BACKGROUND

Whether treatment of gestational diabetes before 20 weeks' gestation improves maternal and infant health is unclear.

METHODS

We randomly assigned, in a 1:1 ratio, women between 4 weeks' and 19 weeks 6 days' gestation who had a risk factor for hyperglycemia and a diagnosis of gestational diabetes (World Health Organization 2013 criteria) to receive immediate treatment for gestational diabetes or deferred or no treatment, depending on the results of a repeat oral glucose-tolerance test [OGTT] at 24 to 28 weeks' gestation (control). The trial included three primary outcomes: a composite of adverse neonatal outcomes (birth at <37 weeks' gestation, birth trauma, birth weight of ≥4500 g, respiratory distress, phototherapy, stillbirth or neonatal death, or shoulder dystocia), pregnancy-related hypertension (preeclampsia, eclampsia, or gestational hypertension), and neonatal lean body mass.

RESULTS

A total of 802 women underwent randomization; 406 were assigned to the immediate-treatment group and 396 to the control group; follow-up data were available for 793 women (98.9%). An initial OGTT was performed at a mean (±SD) gestation of 15.6±2.5 weeks. An adverse neonatal outcome event occurred in 94 of 378 women (24.9%) in the immediate-treatment group and in 113 of 370 women (30.5%) in the control group (adjusted risk difference, -5.6 percentage points; 95% confidence interval [CI], -10.1 to -1.2). Pregnancy-related hypertension occurred in 40 of 378 women (10.6%) in the immediate-treatment group and in 37 of 372 women (9.9%) in the control group (adjusted risk difference, 0.7 percentage points; 95% CI, -1.6 to 2.9). The mean neonatal lean body mass was 2.86 g in the immediate-treatment group and 2.91 g in the control group (adjusted mean difference, -0.04 g; 95% CI, -0.09 to 0.02). No between-group differences were observed with respect to serious adverse events associated with screening and treatment.

CONCLUSIONS

Immediate treatment of gestational diabetes before 20 weeks' gestation led to a modestly lower incidence of a composite of adverse neonatal outcomes than no immediate treatment; no material differences were observed for pregnancy-related hypertension or neonatal lean body mass. (Funded by the National Health and Medical Research Council and others; TOBOGM Australian New Zealand Clinical Trials Registry number, ACTRN12616000924459.).

Obesity and gestational diabetes independently and collectively induce specific effects on placental structure, inflammation and endocrine function in a cohort of South African women

Maternal obesity and gestational diabetes mellitus (GDM) are associated with insulin resistance and health risks for mother and offspring. Obesity is also characterized by low-grade inflammation, which in turn, impacts insulin sensitivity. The placenta secretes inflammatory cytokines and hormones that influence maternal glucose and insulin handling. However, little is known about the effect of maternal obesity, GDM and their interaction, on placental morphology, hormones and inflammatory cytokines. In a South African cohort of non-obese and obese pregnant women with and without GDM, this study examined placental morphology using stereology, placental hormone and cytokine expression using real-time PCR, western blotting and immunohistochemistry, and circulating TNFα and IL-6 concentrations using ELISA. Placental expression of endocrine and growth factor genes was not altered by obesity or GDM. However, LEPTIN gene expression was diminished, syncytiotrophoblast TNFα immunostaining elevated and stromal and fetal vessel IL-6 staining reduced in the placenta of obese women in a manner that was partly influenced by GDM status. Placental TNFα protein abundance and maternal circulating TNFα concentrations were reduced in GDM. Both maternal obesity and, to a lesser extent, GDM were accompanied by specific changes in placental morphometry. Maternal blood pressure and weight gain and infant ponderal index were also modified by obesity and/or GDM. Thus, obesity and GDM have specific impacts on placental morphology and endocrine and inflammatory states that may relate to pregnancy outcomes. These findings may contribute to developing placenta-targeted treatments that improve mother and offspring outcomes, which is particularly relevant given increasing rates of obesity and GDM worldwide. KEY POINTS: Rates of maternal obesity and gestational diabetes (GDM) are increasing worldwide, including in low-middle income countries (LMIC). Despite this, much of the work in the field is conducted in higher-income countries. In a well-characterised cohort of South African women, this study shows that obesity and GDM have specific impacts on placental structure, hormone production and inflammatory profile. Moreover, such placental changes were associated with pregnancy and neonatal outcomes in women who were obese and/or with GDM. The identification of specific changes in the placenta may help in the design of diagnostic and therapeutic approaches to improve pregnancy and neonatal outcomes with particular significant benefit in LMICs.

Establishing Trimester-Specific Haemoglobin A1c Reference Intervals in Pregnant Women: A retrospective study of healthy South Asian women with normal pregnancy outcomes

Objectives

This study aimed to define trimester-specific haemoglobin A1c (HbA1c) reference intervals in healthy, pregnant South Asian women.

Methods

This retrospective study was conducted at St. Stephen's Hospital, Delhi, India, between January 2011 and December 2016. Healthy pregnant women were compared to a control group of healthy non-pregnant women. Pregnant participants had term deliveries of babies with appropriate gestational weights. The HbA1c levels were calculated in terms of non-parametric 2.5 and 97.5 percentiles for women in first (T1), second (T2) and third (T3) trimester groups. Statistical tests were used to obtain the normal HbA1c reference values and were considered significant when P <0.05.

Results

This study included a total of 1,357 healthy pregnant women and a control group of 67 healthy, non-pregnant women. Pregnant women had a median HbA1c of 4.8% (4-5.5%) or 32 mmol/mol (20-39 mmol/mol); non-pregnant women had a median HbA1c of 5.1% (4-5.7%) or 29 mmol/mol (20-37 mmol/mol; P <0.001). The HbA1c levels for the T1, T2 and T3 groups were 4.9% (4.1-5.5%) or 30 mmol/mol (21-37 mmol/mol), 4.8% (4.5-5.3%) or 29 mmol/mol (20-34 mmol/mol) and 4.8% (3.9-5.6%) or 29 mmol/mol (19-38 mmol/mol), respectively. The HbA1c values were significant when comparing T1 versus T2 (P <0.001), T1 versus T3 (P = 0.002) and T1 versus the non-pregnant group (P = 0.001). However, T2 versus T3 was not significant (P = 0.111).

Conclusion

Compared to non-pregnant women, HbA1c levels were lower in pregnant women, despite women in the T2 and T3 groups having a higher body mass index than the women in the T1 and non-pregnant groups. Further research is recommended to understand the factors responsible and validate these findings.

Predicting the Risk of Insulin-Requiring Gestational Diabetes before Pregnancy: A Model Generated from a Nationwide Population-Based Cohort Study in Korea

BACKGRUOUND

The severity of gestational diabetes mellitus (GDM) is associated with adverse pregnancy outcomes. We aimed to generate a risk model for predicting insulin-requiring GDM before pregnancy in Korean women.

METHODS

A total of 417,210 women who received a health examination within 52 weeks before pregnancy and delivered between 2011 and 2015 were recruited from the Korean National Health Insurance database. The risk prediction model was created using a sample of 70% of the participants, while the remaining 30% were used for internal validation. Risk scores were assigned based on the hazard ratios for each risk factor in the multivariable Cox proportional hazards regression model. Six risk variables were selected, and a risk nomogram was created to estimate the risk of insulin-requiring GDM.

RESULTS

A total of 2,891 (0.69%) women developed insulin-requiring GDM. Age, body mass index (BMI), current smoking, fasting blood glucose (FBG), total cholesterol, and γ-glutamyl transferase were significant risk factors for insulin-requiring GDM and were incorporated into the risk model. Among the variables, old age, high BMI, and high FBG level were the main contributors to an increased risk of insulin-requiring GDM. The concordance index of the risk model for predicting insulin-requiring GDM was 0.783 (95% confidence interval, 0.766 to 0.799). The validation cohort's incidence rates for insulin-requiring GDM were consistent with the risk model's predictions.

CONCLUSION

A novel risk engine was generated to predict insulin-requiring GDM among Korean women. This model may provide helpful information for identifying high-risk women and enhancing prepregnancy care.

A Clinical Update on Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) traditionally refers to abnormal glucose tolerance with onset or first recognition during pregnancy. GDM has long been associated with obstetric and neonatal complications primarily relating to higher infant birthweight and is increasingly recognized as a risk factor for future maternal and offspring cardiometabolic disease. The prevalence of GDM continues to rise internationally due to epidemiological factors including the increase in background rates of obesity in women of reproductive age and rising maternal age and the implementation of the revised International Association of the Diabetes and Pregnancy Study Groups' criteria and diagnostic procedures for GDM. The current lack of international consensus for the diagnosis of GDM reflects its complex historical evolution and pragmatic antenatal resource considerations given GDM is now 1 of the most common complications of pregnancy. Regardless, the contemporary clinical approach to GDM should be informed not only by its short-term complications but also by its longer term prognosis. Recent data demonstrate the effect of early in utero exposure to maternal hyperglycemia, with evidence for fetal overgrowth present prior to the traditional diagnosis of GDM from 24 weeks' gestation, as well as the durable adverse impact of maternal hyperglycemia on child and adolescent metabolism. The major contribution of GDM to the global epidemic of intergenerational cardiometabolic disease highlights the importance of identifying GDM as an early risk factor for type 2 diabetes and cardiovascular disease, broadening the prevailing clinical approach to address longer term maternal and offspring complications following a diagnosis of GDM.

Association between the cut-off value of the first trimester fasting plasma glucose level and gestational diabetes mellitus: a retrospective study from southern China

Purpose

Our previous studies have suggested that the first trimester fasting plasma glucose (FPG) level is associated with gestational diabetes mellitus (GDM) and is a predictor of GDM. The aim of the present study was to provide valuable insights into the accuracy of the first trimester FPG level in the screening and diagnosis of GDM in southern China.

Methods

This retrospective study included pregnant women who had their first trimester FPG level recorded at 9–13⁺⁶ weeks and underwent screening for GDM using the 2-h 75 g oral glucose tolerance test (OGTT) between the 24th and 28th gestational weeks. Differences between the GDM and non-GDM groups were assessed by Student’s t test and the chi-squared test according to the nature of the variables. A restricted cubic spine was used to explore the relationship between the first trimester FPG level and the odds ratio (OR) of GDM in pregnant women. Cut-off values of first trimester FPG were determined using receiver operating characteristic (ROC) curves and the area under the curve (AUC), and 95% confidence intervals (CIs), the positive predictive value (PPV) and the negative predictive value (NPV) were calculated.

Results

The medical records of 28,030 pregnant women were analysed, and 4,669 (16.66%) of them were diagnosed with GDM. The average first trimester FPG level was 4.62 ± 0.37 mmol/L. The OR of GDM increased with increasing first trimester FPG levels and with a value of first trimester FPG of approximately 4.6 mmol/L, which was equal to 1 (Chi-Square = 665.79, P < 0.001), and then started to increase rapidly afterwards. The ROC curve for fasting plasma glucose in the first trimester (4.735 mmol/L) for predicting gestational diabetes mellitus in pregnant women was 0.608 (95% CI: 0.598–0.617), with a sensitivity of 0.490 and a specificity of 0.676.

Conclusion

Based on the research, we recommend that all pregnant women undergo FPG testing in the first trimester, particularly at the first antenatal visit. Furthermore, we suggest that the risks of GDM should be given increased attention and management as soon as the first trimester FPG value is more than 4.7 mmol/L. First trimester FPG levels should be considered a screening marker when diagnosing GDM in pregnant women but this needs to be confirmed by more prospective studies. These factors may have a significant impact on the clinical treatment of pregnant women.

Exploring comparative assessment of adiposity measures during pregnancy and postpartum

BACKGROUND & AIMS

Excessive adiposity in pregnancy is associated with an altered cardiometabolic profile and adverse maternal and offspring outcomes. Pre-pregnancy body mass index (pBMI) is a proxy measure for adiposity that is most often used in clinical settings; however, it may not identify at-risk pregnancies caused by adiposity-related cardiometabolic dysfunction. The challenge is that validated direct adiposity measures are limited due to the dynamic nature of pregnancy. This exploratory analysis aimed to, 1) evaluate longitudinal changes in % body fat (BF) and the agreement between skinfold thickness (SFT) and bioelectrical impedance analysis (BIA) across pregnancy and in postpartum; 2) compare the discrimination power of SFT, BIA, and pBMI regarding adiposity status; and 3) assess agreement between SFT and BIA with dual-energy X-ray absorptiometry (DXA) in the postpartum.

METHODS

Participants enrolled in the Be Healthy in Pregnancy (BHIP) RCT (NCT01693510) had demographic data and pBMI collected at enrollment and adiposity measured at 12-17, 26-28, and 36-38 weeks gestation by BIA (%BF) and SFT (sum and %BF), and also by DXA at 6 months postpartum. Agreement between methods was assessed by Bland Altman plots and McNemar's test and C-statistic for discriminative power.

RESULTS

In 181 women with mean pBMI of 25.1 kg/m² (min: 17.4 kg/m², max: 39.6 kg/m²) and age 31.6 (SD: 4.0 yr), maternal adiposity increased significantly (p < 0.001) across pregnancy when measured by the sum of SFT or %BF by BIA, but not %BF by SFT. In early pregnancy, BF by BIA and SFT showed good agreement, with BIA values 1.8% greater than SFT, but low agreement in late pregnancy, with BIA values 7.1% greater than SFT. However, in the postpartum, agreement was similar to early pregnancy, and both BIA and SFT demonstrated good agreement with DXA. By pBMI, 45.5% of participants were categorized as overweight/obese, compared to 66.5% by BIA (p < 0.0001) and 54.5% by SFT (p < 0.0001).

CONCLUSIONS

In comparison to SFT and BIA, the results suggest that pBMI is less sensitive in identifying participants with excessive adiposity, limiting its use as a screening tool for adiposity-related adverse outcomes in pregnancy. It would be preferable to use a direct measure of adiposity to screen for at-risk pregnancies. Both %BF by BIA and sum of SFT can quantify the change in adiposity across pregnancy and in the postpartum and thus could be adopted as clinical practice tools. Future research efforts should further refine and validate adiposity techniques for use, particularly in mid and late pregnancy.

CLINICAL TRIAL

The BHIP clinical trial (NCT01693510). REGISTRATION SITE: https://clinicaltrials.gov/ct2/show/NCT01693510.

Can the First Fasting Plasma Glucose Test in Pregnancy Predict Subsequent Gestational Complications?

Objective

To determine the best cut-off level of pregnant women's first fasting plasma glucose (FFPG) test results for the prediction of subsequent onset of gestational diabetes mellitus (GDM) and to examine the association between FFPG and maternal and neonatal outcomes in a large Caucasian population.

Methods

1437 medical records of women with singleton pregnancies followed up between 2015 and 2018 were retrospectively analyzed. Data on FFPG tested in the first trimester and 75 g oral glucose tolerance test (OGTT) findings performed according to IADPSG criteria and Italian guidelines were collected and evaluated. The women's clinical and metabolic characteristics (age, prepregnancy body mass index (BMI), previous pregnancies complicated by GDM, timing of delivery, and gestational hypertension) were also recorded. The fetal variables considered were being large for gestational age (LGA) or small for gestational age (SGA), macrosomia, and hypoglycemia.

Results

Among the 1437 pregnant women studied, 684 had a normal glucose tolerance (NGT) and 753 developed GDM. In a univariate analysis FFPG ≥92 mg/dl predicts the risk of GDM with an OR = 2.36 (95% CI 1.930-3.186; p < 0.001). In multivariate analysis, after adjusting for principal risk factors of GDM (BMI, previous GDM, age >35 years, family history of diabetes) FFPG ≥92 mg/dl was associated with the risk of GDM (OR = 1.92; 95% CI 1.488-2.492; p < 0.001). In univariate analysis, FFPG ≥92 mg/dl predict the risk of insulin therapy in GDM women with a OR = 1.88 (95% CI 1.230-2.066; p < 0.001). As regards LGA, in a multivariate analysis, after adjusting for BMI, FFPG ≥92 mg/dl was associated with the risk of LGA only in NGT women (OR = 2.34; 95% CI 1.173-4.574; p=0.014), but not in GDM women. FFPG was not associated with other maternal or neonatal outcomes.

Conclusions

FFPG ≥92 mg/dl is related to GDM diagnosis and to the need of insulin therapy if GDM is diagnosed. An early diagnosis and a prompt start of insulin therapy are essential to prevent maternal and fetal complications.

Longitudinal changes in glucose during pregnancy in women with gestational diabetes risk factors

AIMS/HYPOTHESIS

Despite recommendations to screen women with diabetes risk factors for hyperglycaemia in the first trimester, criteria for normal glucose values in early pregnancy have not been firmly established. We aimed to compare glucose levels in early pregnancy with those later in gestation and outside of pregnancy in women with diabetes risk factors.

METHODS

In pregnant women (N = 123) followed longitudinally through the postpartum period, and a separate cohort of non-pregnant women (N = 65), we performed 75 g oral glucose tolerance tests. All participants had one or more risk factors for diabetes. Using linear regression, we tested for differences in glucose levels between non-pregnant and pregnant women at early (7-15 weeks) and mid-late (24-32 weeks) gestation as well as postpartum, with adjustment for maternal age, parity, marital status and BMI. In a longitudinal analysis using mixed-effects models, we tested for differences in glucose levels across early and mid-late pregnancy compared with postpartum. Differences are expressed as β (95% CI).

RESULTS

Fasting glucose was lower in pregnant compared with non-pregnant women by 0.34 (0.18, 0.51) mmol/l (p < 0.0001) in early pregnancy and by 0.45 (0.29, 0.61) mmol/l (p < 0.0001) in mid-late pregnancy. In longitudinal models, fasting glucose was lower by 0.13 (0.04, 0.21) mmol/l (p = 0.003) in early pregnancy and by 0.16 (0.08, 0.25) mmol/l (p = 0.0003) in mid-late pregnancy compared with the same women postpartum. Early pregnancy post-load glucose levels did not differ from those in non-pregnant women or the same women postpartum. In mid-late pregnancy, compared with non-pregnant women, elevations in 1 h post-load glucose level (0.60 [-0.12, 1.33] mmol/l, p = 0.10) and 2 h post-load glucose (0.49 [-0.21, 1.19] mmol/l, p = 0.17) were not statistically significant. However, in longitudinal analyses, 1 h and 2 h post-load glucose levels were higher in mid-late pregnancy (by 0.78 [0.35, 1.21] mmol/l, p = 0.0004, and 0.67 [0.30, 1.04] mmol/l, p = 0.0005, respectively) when compared with postpartum.

CONCLUSIONS/INTERPRETATION

In women with diabetes risk factors, fasting glucose declines in the first trimester. Post-load glucose increases later in pregnancy. These findings may inform criteria for diagnosing hyperglycaemia early in pregnancy.

Prediction of gestational diabetes mellitus in the first trimester by fasting plasma glucose which cutoff is better?

OBJECTIVE

We aimed to predict subsequent gestational diabetes mellitus (GDM) by fasting plasma glucose (FPG) in the first trimester.

METHODS

Healthy pregnant women who were screened for GDM at 24-28 gestational weeks and had FPG levels calculated during their first antenatal visit and less than 14 gestational weeks were included in this study.

RESULTS

Of the 2605 women who were recruited for the study, 245 (9.4%) were diagnosed with GDM at weeks 24-28. The diagnostic accuracy for FPG predicting GDM was 66.5, 78.4, and 88.2 for the cutoff values of 87.5 mg/dl, 92 mg/dl, and 99.5 mg/dl, respectively.

CONCLUSIONS

FPG values which are within the normoglycaemic range constitute an independent risk factor for the development of GDM. The threshold for gestational diabetes diagnosis must be revised.

Beta-Cell Adaptation to Pregnancy - Role of Calcium Dynamics

During pregnancy, the mother develops insulin resistance to shunt nutrients to the growing fetus. As a result, the maternal islets of Langerhans undergo several changes to increase insulin secretion in order to maintain glucose homeostasis and prevent the development of gestational diabetes. These changes include an increase in β-cell proliferation and β-cell mass, upregulation of insulin synthesis and insulin content, enhanced cell-to-cell communication, and a lowering of the glucose threshold for insulin secretion, all of which resulting in an increase in glucose-stimulated insulin secretion. Emerging data suggests that a change in intracellular calcium dynamics occurs in the β-cell during pregnancy as part of the adaptive process. Influx of calcium into β-cells is crucial in the regulation of glucose-stimulated insulin secretion. Calcium fluxes into and out of the cytosol, endoplasmic reticulum, and mitochondria are also important in controlling β-cell function and survival. Here, we review calcium dynamics in islets in response to pregnancy-induced changes in hormones and signaling molecules, and how these changes may enhance insulin secretion to stave off gestational diabetes.

Predictors of later insulin therapy for gestational diabetes diagnosed in early pregnancy

Interventions for gestational diabetes mellitus (GDM), diagnosed in early pregnancy, have been a topic of controversy. This study aimed to elucidate factors that predict patients with GDM diagnosed before 24 gestational weeks (early GDM: E-GDM) who require insulin therapy later during pregnancy. Furthermore, we identified patients whose impaired glucose tolerance should be strictly controlled from early gestation onward. Women diagnosed with GDM were categorized based on the gestational age at diagnosis into E-GDM (n = 388) or late GDM (L-GDM, diagnosed after 24 weeks, n = 340) groups. Clinical features were compared between the groups, and the predictors for insulin therapy was evaluated in the E-GDM group. There were no significant between-group differences in terms of perinatal outcomes (e.g., gestational weeks at delivery, fetal growth, hypertensive disorder of pregnancy), with the exception of the Apgar score at 5 min. Moreover, there was no significant difference in the frequency of insulin therapy during pregnancy between the two groups. Using multiple logistic regression analysis, pre-pregnancy body mass index (BMI) ≥25 kg/m², a family history of diabetes, and higher fasting plasma glucose (FPG), 1 h-plasma glucose (PG), and 2 h-PG values increased insulin therapy risk during pregnancy in the E-GDM group. Furthermore, since E-GDM patients with abnormal levels of FPG, as well as 1 h-PG or 2 h-PG, and those with pre-pregnancy BMI ≥25 kg/m² and a family history of diabetes had a higher risk of later insulin therapy during pregnancy, they may require more careful follow-up in the perinatal period.

Early Gestational Diabetes Mellitus: Diagnostic Strategies and Clinical Implications

Preexisting diabetes mellitus (DM) should be ruled out early in pregnancy in those at risk. During screening, a significant proportion of women do not reach the threshold for overt DM but fulfill the criteria used for diagnosing conventional gestational DM (cGDM). There is no consensus on the management of pregnancies with intermediate levels of hyperglycemia thus diagnosed. We have used the term early gestational DM (eGDM) for this condition and reviewed the currently available literature. Fasting plasma glucose (FPG), oral glucose tolerance test, and glycated hemoglobin (HbA1c) are the commonly employed screening tools in early pregnancy. Observational studies suggest that early pregnancy FPG and Hba1c correlate with the risk of cGDM and adverse perinatal outcomes. However, specific cut-offs, including those proposed by the International Association of the Diabetes and Pregnancy Study Group, do not reliably predict the development of cGDM. Emerging data, though indicate that FPG ≥ 92 mg/dL (5.1 mmol/L), even in the absence of cGDM, signals the risk for perinatal complication. Elevated HbA1c, especially a level ≥ 5.9%, also correlates with the risk of cGDM and worsened outcome. HbA1c as a diagnostic test is however besieged with the usual caveats that occur in pregnancy. The studies that explored the effects of intervention present conflicting results, including a possibility of fetal malnutrition and small-for-date baby in the early treatment group. Diagnostic thresholds and glycemic targets in eGDM may differ, and large multicenter randomized controlled trials are necessary to define the appropriate strategy.

Prediabetes and pregnancy: Early pregnancy HbA1c identifies Australian Aboriginal women with high-risk of gestational diabetes mellitus and adverse perinatal outcomes

AIMS

To assess whether early pregnancy HbA1c can predict gestational diabetes mellitus (GDM) and adverse birth outcomes in Australian women.

METHODS

Prospective study of 466 women without diabetes, aged ≥16-years at first antenatal presentation. Recruitment was from 27 primary healthcare sites in rural and remote Australia from 9-January 2015 to 31-May 2018. HbA1c was measured with first antenatal investigations (<20-weeks gestation). Primary outcome measure was predictive value of HbA1c for GDM, by routine 75 g oral glucose tolerance test (OGTT; ≥24-weeks gestation), and for large-for-gestational-age (LGA) newborn.

RESULTS

Of 396 (129 Aboriginal) women with routine OGTT, 28.8% had GDM (24.0% Aboriginal). HbA1c ≥5.6% (≥38 mmol/mol) was highly predictive (71.4%, 95% CI; 47.8-88.7%) for GDM in Aboriginal women, and in the total cohort increased risk for LGA newborn (RR 2.04, 95% CI; 1.03-4.01, P = 0.040). There were clear differences between Aboriginal and non-Aboriginal women: 16.3% v 5.2% (P < 0.001) had elevated HbA1c whereas 12.4% v 29.6% (P < 0.001) developed hyperglycemia during pregnancy.

CONCLUSIONS

Early pregnancy HbA1c ≥5.6% (≥38 mmol/mol) identifies Aboriginal women with apparent prediabetes and elevated risk of having an LGA newborn. Universal HbA1c at first antenatal presentation could facilitate earlier management of hyperglycemia and improved perinatal outcome in this high-risk population.

Type 1 Diabetes: Management in Women From Preconception to Postpartum

CONTEXT

This review presents an up-to-date summary on management of type 1 diabetes mellitus (T1DM) among women of reproductive age and covers the following time periods: preconception, gestation, and postpartum.

EVIDENCE ACQUISITION

A systematic search and review of the literature for randomized controlled trials and other studies evaluating management of T1DM before pregnancy, during pregnancy, and postpartum was performed.

EVIDENCE SYNTHESIS

Preconception planning should begin early in the reproductive years for young women with T1DM. Preconception and during pregnancy, it is recommended to have near-normal glucose values to prevent adverse maternal and neonatal outcomes, including fetal demise, congenital anomaly, pre-eclampsia, macrosomia, neonatal respiratory distress, neonatal hyperbilirubinemia, and neonatal hypoglycemia.

CONCLUSION

Women with T1DM can have healthy, safe pregnancies with preconception planning, optimal glycemic control, and multidisciplinary care.

Early gestational diabetes mellitus (GDM) is associated with worse pregnancy outcomes compared with GDM diagnosed at 24-28 weeks gestation despite early treatment

BACKGROUND

Gestational diabetes mellitus (GDM) is associated+ with adverse pregnancy outcomes compared with women with normal glucose tolerance in pregnancy. The WHO recommends screening at 24-28 weeks gestation for GDM. Women who are diagnosed before 24-28 weeks gestation have a longer intervention period which may impact positively on pregnancy outcomes.

AIM

This study aimed to examine pregnancy outcomes of women with GDM diagnosed <24 weeks gestation compared with those diagnosed at 24-28 weeks in a large Irish cohort.

METHODS

A retrospective cohort study of 1471 pregnancies in women with GDM diagnosed using IADPSG criteria between September 2012 and April 2016 was conducted. At GDM diagnosis, women were classified as early GDM <24 weeks or standard GDM 24-28 weeks gestation.

RESULTS

Women with early GDM had a significantly greater risk of pregnancy-induced hypertension (12.4% vs. 5.3%; P < 0.05), post-partum haemorrhage (8.7% vs. 2.4%; P < 0.05) and post-partum glucose abnormalities (32% vs. 15.6%; P < 0.05). Their offspring had a greater risk of pre-maturity (10.9% vs. 6.6%; P < 0.05), stillbirth (1.4% vs. 0.5%; P < 0.05), large for gestational age (19.1% vs. 13.4% P < 0.05) and need neonatal intensive care (30.7% vs. 22.1%; P < 0.05) compared with offspring of women with standard GDM. Rates of C-section and pre-maturity were still higher in the early GDM group when the two groups where compared based on their post-natal OGTT.

CONCLUSION

Early GDM women and their offspring are at greater risk of an adverse pregnancy outcome compared with those diagnosed at 24-28 weeks. In view of the abnormal post-natal glucose findings, early GDM may reflect a more advanced state in diabetes pathogenesis.

Early Screening for Gestational Diabetes Using IADPSG Criteria May Be a Useful Predictor for Congenital Anomalies: Preliminary Data from a High-Risk Population

Background: Our aim was to investigate whether the International Association of the Diabetes and Pregnancy Study Groups (IADPSG) glycemic thresholds used for detecting hyperglycemia in pregnancy can be predictive for malformations in women with hyperglycemia detected in early pregnancy. Methods: a single-center, retrospective observational trial of 125 mother-infant pairs from singleton pregnancies with hyperglycemia according to the IADPSG criteria diagnosed at the gestational age below 16 weeks. Glucose values obtained from 75-g OGTT (oral glucose tolerance test) were investigated as predictors for congenital malformations in newborns. Results: Characteristics of the cohort: maternal age: 31.5 ± 5.2, pre-pregnancy body mass index (BMI) ≥ 30 kg/m²: 42.0%, gestational age at diagnosis (weeks): 12.0 ± 4.0, and newborns with congenital malformations: 8.8%. Fasting blood glycemia (FBG) and HbA1c (Haemoglobin A1c) at baseline significantly predicted the outcome (expB: 1.06 (1.02–1.1), p = 0.007 and expB: 2.05 (1.24–3.38), p = 0.005, respectively). Both the fasting blood glucose (FBG) value of 5.1 mmol/dL (diagnostic for gestational diabetes mellitus (GDM)) and 5.5 mmol/dL (upper limit for normoglycemia in the general population) significantly increased the likelihood ratio (LR) for fetal malformations: 1.3 (1.1; 1.4) and 1.5 (1.0; 2.4), respectively. Conclusions: (1) Fasting glycemia diagnostic for GDM measured in early pregnancy is associated with a significantly elevated risk for congenital malformations. (2) Our data suggest that women at elevated risks of GDM/diabetes in pregnancy (DiP) should have their fasting blood glucose assessed before becoming pregnant, and the optimization of glycemic control should be considered if the FBG exceeds 5.1 mmol/dL.

Maternal Obesity Affects the Glucose-Insulin Axis During the First Trimester of Human Pregnancy

Background and objective: The maternal glucose-insulin axis is central for metabolic adaptations required for a healthy pregnancy. Metabolic changes in obese mothers in early pregnancy have been scantly described. Here we characterized the glucose-insulin axis in the first trimester of human pregnancy and assessed the effect of maternal obesity and fat mass. Methods: In this cross-sectional study, maternal blood samples (N = 323) were collected during voluntary pregnancy termination (gestational age 4+0-11+6 weeks) after overnight fasting. Smokers (N = 198) were identified by self-report and serum cotinine levels (ELISA). Maternal BMI (kg/m2) and serum leptin (ELISA) were used as proxy measures of obesity and maternal fat mass, respectively. BMI was categorized into under-/normal weight (BMI < 25.0 kg/m2), overweight (BMI 25.0-29.9 kg/m2) and obese (BMI ≥ 30.0 kg/m2), and leptin in tertiles (1st tertile: leptin < 6.80 ng/ml, 2nd tertile: leptin 6.80-12.89 ng/ml, 3rd tertile: leptin > 12.89 ng/ml). ISHOMA insulin sensitivity index was calculated from glucose and C-peptide (ELISA) serum concentrations. Analyses of covariance including multiple confounders were performed to test for differences in glucose, C-peptide and ISHOMA between gestational age periods, BMI and leptin groups. C-peptide and ISHOMA were log-transformed before analyses. Results: At weeks 7-9, fasting glucose and C-peptide levels were lower (P < 0.01 and P < 0.001, respectively) and insulin sensitivity higher (P < 0.001) than at weeks 4-6. Glucose levels were not significantly different between BMI or leptin categories. In contrast, C-peptide increased by 19% (P < 0.01) between the normal weight and the overweight group and by 39% (P < 0.001) between the overweight and obese group. In the leptin groups, C-peptide increased by 25% (P < 0.001) between the 1st and 2nd leptin tertile and by 15% (P < 0.05) between the 2nd and 3rd leptin tertile. ISHOMA decreased with higher BMI and fat mass. ISHOMA decreased by 18% (P < 0.01) between the normal weight and the overweight group and by 30% (P < 0.01) between the overweight and the obese group. In the leptin groups, ISHOMA decreased by 22% (P < 0.001) between the 1st and 2nd leptin tertile and by 14% (P < 0.05) between the 2nd and 3rd leptin tertile. Conclusions: At the group level, fasting glucose, C-peptide and insulin sensitivity dynamically change in the first trimester of human pregnancy. Maternal obesity is associated with higher C-peptide and lower insulin sensitivity at all periods in the first trimester of human pregnancy, while glucose is unaltered. These findings have implications for the timing of early gestational diabetes mellitus risk screening.

High probability of false-positive gestational diabetes mellitus diagnosis during early pregnancy

INTRODUCTION

This study aimed to assess the validity of applying the International Association of Diabetes and Pregnancy Study Group (IADPSG) criteria for the diagnosis of gestational diabetes mellitus (GDM) at any time during pregnancy.

RESEARCH DESIGN AND METHODS

This multicenter cohort study was conducted at five Japanese facilities from January 2018 to April 2019. The study cohort included women at a high risk of GDM who met one or more of the following IADPSG criteria during early pregnancy: fasting plasma glucose (FPG) ≥92 mg/dL and 75 g oral glucose tolerance test (OGTT) value of ≥180 mg/dL at 1 hour, or ≥153 mg/dL at 2 hour (hereafter early-onset GDM). Women diagnosed with early-onset GDM were followed up without therapeutic intervention and underwent the 75 g OGTT again during 24-28 weeks of gestation. Those exhibiting the GDM patterns on the second 75 g OGTT were diagnosed with true GDM and treated, whereas those exhibiting the normal patterns were diagnosed with false positive early GDM and received no therapeutic intervention.

RESULTS

Of the 146 women diagnosed with early-onset GDM, 69 (47%) had normal 75 g OGTT values at 24-28 weeks of gestation, indicating a false-positive result. FPG levels were significantly higher in the first 75 g-OGTT test than in the second 75 g-OGTT test (93 mg/dL and 87.5 mg/dL, respectively; p<0.001). FPG levels were high in 86 (59%) women with early-onset GDM during early pregnancy but in only 39 (27%) women during mid-pregnancy. Compared with false positive early GDM, true GDM was more frequently associated with adverse pregnancy outcomes.

CONCLUSIONS

Although women with early-onset GDM were followed up without treatment, the results of repeated 75 g OGTT during mid-pregnancy were normal in about 50%. Our data did not support the adoption of IADPSG thresholds for the diagnosis of GDM prior to 20 weeks of gestation.

First-trimester fasting glycemia as a predictor of gestational diabetes (GDM) and adverse pregnancy outcomes

AIMS

Studies to prevent gestational diabetes (GDM) have shown the best results when lifestyle measures have been applied early in pregnancy. We aimed to investigate whether first-trimester fasting plasma glucose (FPG) could predict GDM risk and adverse pregnancy outcomes.

METHODS

A retrospective analysis of prospectively collected data from singleton pregnancies who were attended at our hospital between 2008 and 2018 (n = 27,198) was performed. We included patients with a recorded first-trimester FPG and complete pregnancy data (n = 6845). Patients under 18, with pregestational diabetes or reproductive techniques, were excluded. First-trimester FPG was evaluated as a continuous variable and divided into quartiles. GDM was diagnosed by NDDG criteria. The relationship between first- and second-trimester glucose > 92 mg/dL was also investigated. The relationship between FPG and pregnancy outcomes was assessed in 6150 patients who did not have GDM.

RESULTS

Maternal age was 34.2 ± 3.9 years, BMI 23.1 ± 3.7 kg/m² and mean FPG 83.0 ± 7.3 mg/dL. Glucose quartiles were: ≤ 78, 79-83, 84-87 and ≥ 88 mg/dL. First-trimester FPG predicted the risk of GDM (7%, 8%, 10.2% and 16% in each quartile, p < 0.001) and the risk of second-trimester glucose > 92 mg/dL (2.6%, 3.8%, 6.3% and 11.4% in each quartile, p < 0.001). FPG was significantly associated with LGA (8.2%, 9.3%, 10% and 11.7% in each quartile, p = 0.011) but not with other obstetrical outcomes. In a multivariate analysis including age, BMI, tobacco use, number of pregnancies and weight gained during pregnancy, first-trimester FPG was an independent predictor of LGA.

CONCLUSIONS

First-trimester FPG is an early marker of GDM and LGA.

Oral glucose tolerance test results in early pregnancy: A Finnish population-based cohort study

AIMS

To analyze early-pregnancy oral glucose tolerance test (OGTT) results and differences between early- and late-pregnancy OGTT results in a population-based cohort.

METHODS

From 3/2013 to 12/2016, pregnant women in South Karelia, Finland, were invited to undergo a 2-hour 75 g OGTT at 12-16 weeks' gestation (OGTT1) and, if normal, repeat testing at 24-28 weeks (OGTT2). Early and late gestational diabetes (GDM) were diagnosed using the same nationally endorsed criteria (fasting [FPG], 1- or 2-hour plasma glucose ≥5.3, ≥10.0 or ≥8.6 mmol/L, respectively).

RESULTS

In OGTT1 (n = 1401), the mean (SD) FPG, 1- and 2-hour values were 4.85 (0.34), 6.63 (1.73) and 5.60 (1.28) mmol/L, respectively. Early GDM was diagnosed in 209 (14.9%). In OGTT2 (n = 1067), late GDM was diagnosed in 114 (10.6%). In women without GDM (n = 953), the mean FPG values were higher and post-load values lower in OGTT1 vs. OGTT2. No interaction effects of gestational timepoint and maternal BMI on OGTT results were detected, except for the 2-hour value. In women with late GDM, both mean FPG and post-load values were lower in OGTT1 vs. OGTT2. Results were similar employing the IADPSG GDM criteria.

CONCLUSIONS

Our findings suggest that gestational-age specific OGTT thresholds for early GDM diagnosis need to be generated.

Gestational Diabetes Mellitus Screening and Diagnosis

An ideal screening test for gestational diabetes should be capable of identifying not only women with the disease but also the women with a high risk of developing gestational diabetes mellitus (GDM). Screening and diagnosis are the main steps leading to the way of management. There is a lack of consensus among healthcare professionals regarding the screening methods worldwide. Different study groups advocate a variety of screening methods with the support of evidence-based comprehensive data. Some of the organizations suggest screening for high risk or all pregnant women, while others prefer to offer definitive testing without screening. Glycemic thresholds are also not standardized to decide GDM among different guidelines. Prevalence rates of GDM vary between populations and with the choice of glucose thresholds for both screening and definitive tests. One-step or two-step methods have been used for GDM diagnosis. However, screening includes selecting patients with historical risk factors, 50 g 1-h glucose challenge test, fasting plasma glucose, random plasma glucose, and hemoglobin A1c with different cutoffs. In this chapter, screening and diagnosis methods of GDM accepted by different study groups will be discussed which will be followed by the evaluation of different glycemic thresholds. Then the advantages and disadvantages of used methods will be explained and the chapter will finish with an evaluation of the current international guidelines.

Difference in the prevalence of gestational diabetes mellitus according to gestational age at 75-g oral glucose tolerance test in Japan: The Japan Assessment of Gestational Diabetes Mellitus Screening trial

AIMS/INTRODUCTION

To evaluate the differences in the results of 75-g oral glucose tolerance tests (OGTTs) according to gestational age in Japan.

MATERIALS AND METHODS

In this prospective cohort study, 2,578 pregnant women were divided into three categories based on their gestational age during the 75-g OGTT: <14 weeks' gestation, 14-23 weeks' gestation and 24-32 weeks' gestation. The association between gestational age and the results of the 75-g OGTT were evaluated using multivariable analysis.

RESULTS

Early gestational age was associated with high fasting plasma glucose levels at the time of the 75-g OGTT, and low corresponding 1-h and 2-h plasma glucose levels. Compared with women with a gestational age of 24-32 weeks, women who had undergone the 75-g OGTT at <14 weeks' gestation had significantly higher odds of gestational diabetes mellitus diagnosis based on the currently used criteria in Japan (adjusted odds ratio 1.42, 95% confidence interval 1.07-1.90).

CONCLUSIONS

The results of the 75-g OGTT varied by gestational age. The use of the same 75-g OGTT cut-off values for the diagnosis of gestational diabetes mellitus, regardless of gestational age, might lead to increases in the prevalence of gestational diabetes mellitus diagnosis in Japan.

Research Gaps in Gestational Diabetes Mellitus: Executive Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop

The National Institute of Diabetes and Digestive and Kidney Diseases convened a workshop on research gaps in gestational diabetes mellitus (GDM) with a focus on 1) early pregnancy diagnosis and treatment and 2) pharmacologic treatment strategies. This article summarizes the proceedings of the workshop. In early pregnancy, the appropriate diagnostic criteria for the diagnosis of GDM remain poorly defined, and an effect of early diagnosis and treatment on the risk of adverse outcomes has not been demonstrated. Despite many small randomized controlled trials of glucose-lowering medication treatment in GDM, our understanding of medication management of GDM is incomplete as evidenced by discrepancies among professional society treatment guidelines. The comparative effectiveness of insulin, metformin, and glyburide remains uncertain, particularly with respect to long-term outcomes. Additional topics in need of further research identified by workshop participants included phenotypic heterogeneity in GDM and novel and individualized treatment approaches. Further research on these topics is likely to improve our understanding of the pathophysiology and treatment of GDM to improve both short- and long-term outcomes for mothers and their children.

Apolipoprotein A-I Protects Against Pregnancy-Induced Insulin Resistance in Rats

Objective- Insulin resistance and inflammation in pregnancy are risk factors for gestational diabetes mellitus. Increased plasma HDL (high-density lipoprotein) and apo (apolipoprotein) A-I levels have been reported to improve glucose metabolism and inhibit inflammation in animals and humans. This study asks whether increasing plasma apoA-I levels improves insulin sensitivity and reduces inflammation in insulin-resistant pregnant rats. Approach and Results- Insulin-resistant pregnant rats received intravenous infusions of lipid-free apoA-I (8 mg/kg) or saline on days 6, 9, 12, 15, and 18 of pregnancy. The rats were then subjected to a euglycemic-hyperinsulinemic clamp. Glucose uptake was increased in white and brown adipose tissue by 57±13% and 32±10%, respectively ( P<0.05 for both), and in quadriceps and gastrocnemius muscle by 35±9.7% and 47±14%, respectively ( P<0.05 for both), in the apoA-I-treated pregnant rats relative to saline-infused pregnant rats. The pregnant rats that were treated with apoA-I also had reduced plasma TNF-α (tumor necrosis factor-α) levels by 57±8.4%, plasma IL (interleukin)-6 levels by 67±9.5%, and adipose tissue macrophage content by 54±8.2% ( P<0.05 for all) relative to the saline-treated pregnant rats. Conclusions- These studies establish that apoA-I protects against pregnancy-induced insulin resistance in rats by increasing insulin sensitivity in adipose tissue and skeletal muscle and inhibiting inflammation. This identifies apoA-I as a potential target for preventing pregnancy-induced insulin resistance and reducing the incidence of gestational diabetes mellitus.

Frequency and risk factors for recurrent gestational diabetes mellitus in primiparous women: a case control study

BACKGROUND

To investigate the frequency and risk factors for recurrent gestational diabetes mellitus (GDM) in Chinese primiparous women.

METHODS

Case control study. We investigated primiparous women who experienced GDM complications and had a subsequent pregnancy in the same hospital from January, 2012 to January, 2017. Ultimately, 78 women with recurrent GDM and 64 women with no recurrence were included. Clinical characteristics and biochemical parameters such as fasting plasma glucose (FPG), oral glucose tolerance test (OGTT) and lipid profiles were collected from medical records. We used an independent t-test and Chi-square test or Fisher's exact test to compare each variable. Univariate and multivariate logistic analyses were used to compute each odds ratio (OR) and 95% confidence interval (CI).

RESULTS

The frequency of recurrent GDM was 55%. We found postprandial 1-h glucose at the 75-g OGTT was positively related to GDM recurrence, whereas first-trimester FPG in first pregnancy was negatively related. The first-trimester HbA1c value was higher in the group with GDM recurrence than in the group with no recurrence, though the difference was not significant. Moreover, the group with GDM recurrence manifested significantly higher first-trimester triglyceride concentrations in subsequent pregnancies; the adjusted ORs (95% CI) were 1.43 (1.09-1.87), 0.24 (0.10-0.63), 3.59 (0.93-13.88) and 1.89 (1.13-3.16).

CONCLUSIONS

GDM recurred in more than half of subsequent pregnancies. Women with lower first-trimester FPG and higher postprandial 1-h glucose in first pregnancy, and with higher first-trimester triglyceride in subsequent pregnancy were at increased risk for GDM recurrence.

Dietary Quality and Glycemic Control Among Women with Gestational Diabetes Mellitus

BACKGROUND/OBJECTIVE

Poor dietary quality, measured by the Healthy Eating Index 2010 (HEI-2010), is associated with risk of gestational diabetes mellitus (GDM) and type 2 diabetes. The aim was to investigate the association between dietary quality and glycemic control in women with GDM.

MATERIALS AND METHODS

The study included 1220 women with GDM. Dietary quality was calculated by HEI-2010 score from a Food Frequency Questionnaire administered shortly after GDM diagnosis; higher scores indicate higher dietary quality. Subsequent glycemic control was defined as ≥80% of all capillary glucose measurements meeting recommended clinical targets below 95 mg/dL for fasting, and below 140 mg/dL 1-hour glucose after meals.

RESULTS

As compared with Quartile 1 of HEI-2010 score, Quartiles 2, 3, and 4 showed increased adjusted odds of overall optimal glycemic control (odds ratio [95% confidence interval] 1.90 [1.34-2.70], 1.77 [1.25-2.52], and 1.55 [1.09-2.20], respectively). Increased odds of glycemic control were observed in Quartiles 2, 3, and 4 as compared with Quartile 1 of HEI-2010 score for 1-hour postbreakfast and 1-hour postdinner. Mean capillary glucose was lower in Quartiles 2, 3, and 4 of HEI-2010 score when compared with Quartile 1 for 1-hour postdinner (p = 0.03).

CONCLUSIONS

Clinicians should be aware that even a small improvement in diet quality may be beneficial for the achievement of improved glycemic control in women with GDM.

TRIAL REGISTRATION

Clinical Trials.gov number, NCT01344278.

Cognitive costs of reproduction: life-history trade-offs explain cognitive decline during pregnancy in women

Life-history theory predicts that access to limited resources leads to trade-offs between competing body functions. Women, who face higher costs of reproduction when compared to men, should be especially vulnerable to these trade-offs. We propose the 'cognitive costs of reproduction hypothesis', which states that energy trade-offs imposed by reproduction may lead to a decline in maternal cognitive function during gestation. In particular, we hypothesize that the decline in cognitive function frequently observed during pregnancy is associated with the allocation of resources between the competing energetic requirements of the mother's brain and the developing foetus. Several distinctive anatomical and physiological features including a high metabolic rate of the brain, large infant size, specific anatomical features of the placenta and trophoblast, and the lack of maternal control over glucose flow through the placenta make the occurrence of these trade-offs likely. Herein, we review several lines of evidence for trade-offs between gestation and cognition that are related to: (i) energy metabolism during reproduction; (ii) energy metabolism of the human brain; (iii) links between energy metabolism and cognitive function; and (iv) links between gestation and cognitive function. We also review evidence for the important roles of cortisol, corticotropin-releasing hormone and sex hormones in mediating the effects of gestation on cognition, and we discuss possible neurophysiological mechanisms underlying the observed effects. The evidence supports the view that energy trade-offs between foetal growth and maternal endocrine and brain function lead to changes in maternal cognition, and that this phenomenon is mediated by neuroendocrine mechanisms involving the hypothalamic-pituitary-adrenal axis, brainstem nucleus locus coeruleus and hippocampus.

FIGO analysis of research priorities in hyperglycemia in pregnancy

Hyperglycemia in pregnancy (HIP) is recognized as a major underlying cause of pregnancy complications and a contributing cause to health risks throughout the subsequent life of both mothers and babies, with amplification of the global epidemic of non-communicable diseases. Although some aspects of these associations are well described, detailed understanding of basic pathophysiologic mechanisms is lacking. Improved fundamental scientific knowledge must be developed to allow logical strategies for prevention and treatment. During pregnancy, much work is required to replace current empirical approaches to diagnosis and treatment of HIP with evidence based protocols, pragmatically adapted to differing health care and health economic contexts. Further, a life cycle approach to HIP, the risk of immediate pregnancy complications and later health risks to mother and baby must be developed and implemented across a wide range of health care environments. This document aims to outline key focus areas for further basic, epidemiologic, clinical and implementation research in this important area.

Risk factors for hyperglycemia in pregnancy in the DALI study differ by period of pregnancy and OGTT time point

OBJECTIVE

Risk factors are widely used to identify women at risk for gestational diabetes mellitus (GDM) without clear distinction by pregnancy period or oral glucose tolerance test (OGTT) time points. We aimed to assess the clinical risk factors for Hyperglycemia in pregnancy (HiP) differentiating by these two aspects.

DESIGN AND METHODS

Nine hundred seventy-one overweight/obese pregnant women, enrolled in the DALI study for preventing GDM. OGTTs were performed at ≤19 + 6, 24-28 and 35-37 weeks (IADPSG/WHO2013 criteria). Women with GDM or overt diabetes at one time point did not proceed to further OGTTs. Potential independent variables included baseline maternal and current pregnancy characteristics.

STATISTICAL ANALYSIS

Multivariate logistic regression.

RESULTS

Clinical characteristics independently associated with GDM/overt diabetes were at ≤19 + 6 weeks, previous abnormal glucose tolerance (odds ratio (OR): 3.11; 95% CI: 1.41-6.85), previous GDM (OR: 2.22; 95% CI: 1.20-4.11), neck circumference (NC) (OR: 1.58; 95% CI: 1.06-2.36 for the upper tertile), resting heart rate (RHR, OR: 1.99; 95% CI: 1.31-3.00 for the upper tertile) and recruitment site; at 24-28 weeks, previous stillbirth (OR: 2.92; 95% CI: 1.18-7.22), RHR (OR: 3.32; 95% CI: 1.70-6.49 for the upper tertile) and recruitment site; at 35-37 weeks, maternal height (OR: 0.41; 95% CI: 0.20-0.87 for upper tertile). Clinical characteristics independently associated with GDM/overt diabetes differed by OGTT time point (e.g. at ≤19 + 6 weeks, NC was associated with abnormal fasting but not postchallenge glucose).

CONCLUSION

In this population, most clinical characteristics associated with GDM/overt diabetes were non-modifiable and differed by pregnancy period and OGTT time point. The identified risk factors can help define the target population for future intervention trials.

A Novel Early Pregnancy Risk Prediction Model for Gestational Diabetes Mellitus

INTRODUCTION

Accurate early risk prediction for gestational diabetes mellitus (GDM) would target intervention and prevention in women at the highest risk. We evaluated novel biomarker predictors to develop a first-trimester risk prediction model in a large multiethnic cohort.

METHODS

Maternal clinical, aneuploidy and pre-eclampsia screening markers (PAPP-A, free hCGβ, mean arterial pressure, uterine artery pulsatility index) were measured prospectively at 11-13+6 weeks' gestation in 980 women (248 with GDM; 732 controls). Nonfasting glucose, lipids, adiponectin, leptin, lipocalin-2, and plasminogen activator inhibitor-2 were measured on banked serum. The relationship between marker multiples-of-the-median and GDM was examined with multivariate regression. Model predictive performance for early (< 24 weeks' gestation) and overall GDM diagnosis was evaluated by receiver operating characteristic curves.

RESULTS

Glucose, triglycerides, leptin, and lipocalin-2 were higher, while adiponectin was lower, in GDM (p < 0.05). Lipocalin-2 performed best in Caucasians, and triglycerides in South Asians with GDM. Family history of diabetes, previous GDM, South/East Asian ethnicity, parity, BMI, PAPP-A, triglycerides, and lipocalin-2 were significant independent GDM predictors (all p < 0.01), achieving an area under the curve of 0.91 (95% confidence interval [CI] 0.89-0.94) overall, and 0.93 (95% CI 0.89-0.96) for early GDM, in a combined multivariate prediction model.

CONCLUSIONS

A first-trimester risk prediction model, which incorporates novel maternal lipid markers, accurately identifies women at high risk of GDM, including early GDM.

Hyperglycaemia in early pregnancy: the Treatment of Booking Gestational diabetes Mellitus (TOBOGM) study. A randomised controlled trial

BACKGROUND

Gestational diabetes mellitus (GDM) causes adverse pregnancy outcomes that can be averted by treatment from 24-28 weeks' gestation. Assessing and treating women for overt diabetes in pregnancy (ODIP) at the first antenatal clinic booking is now recommended in international guidelines. As a consequence, women with milder hyperglycaemia are being diagnosed and treated for early GDM, but randomised controlled trial (RCTs) assessing the benefits and harms of such treatment have not been undertaken. The Treatment Of Booking Gestational diabetes Mellitus (TOBOGM) study is a multi-centre RCT examining whether diagnosing and treating GDM diagnosed at booking improves pregnancy outcomes. Methods and analysis: 4000 adult pregnant women (< 20 weeks' gestation) at risk of ODIP will be recruited from 12 hospital antenatal booking clinics and referred for an oral glucose tolerance test (OGTT). 800 women with hyperglycaemia (ie, booking GDM) according to the 2014 Australasian Diabetes-in-Pregnancy Society criteria for pregnant women at 24-28 weeks' gestation will be randomised to immediate treatment for GDM (intervention) or to no treatment (control), pending the results of a second OGTT at 24-28 weeks' gestation. Antenatal and GDM care will otherwise follow local guidelines. Randomisation will be stratified by site and OGTT glycaemic risk strata. The primary pregnancy outcome is a composite of respiratory distress, phototherapy, birth trauma, birth before 37 weeks' gestation, stillbirth or death, shoulder dystocia, and birthweight ≥ 4.5 kg. The primary neonatal outcome is neonatal lean body mass. The primary maternal outcome is pre-eclampsia. Ethics approval: South Western Sydney Local Health District Research and Ethics Office (reference, 15/LPOOL/551). Dissemination of results: Peer-reviewed publications, scientific meetings, collaboration with research groups undertaking comparable studies, discussions with guideline groups and policy makers.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry, ACTRN12616000924459.

Implications of Lipids in Neonatal Body Weight and Fat Mass in Gestational Diabetic Mothers and Non-Diabetic Controls

PURPOSE OF REVIEW

Maternal lipid metabolism greatly changes during pregnancy and we review in this article how they influence fetal adiposity and growth under non-diabetic and gestational diabetic conditions.

RECENT FINDINGS

In pregnant women without diabetes (control), maternal glycemia correlates with neonatal glycemia, neonatal body weight and fat mass. In pregnant women with gestational diabetes mellitus (GDM), maternal glucose correlates with neither neonatal glycemia, neonatal birth weight nor fat mass, but maternal triacylglycerols (TAG), non-esterified fatty acids (NEFA) and glycerol do correlate with birth weight and neonatal adiposity. The proportions of maternal plasma arachidonic (AA) and docosahexaenoic (DHA) acids decrease from the first to the third trimester of pregnancy, and at term these long-chain polyunsaturated fatty acids are higher in cord blood plasma than in mothers, indicating efficient placental transfer. In control or pregnant women with GDM at term, the maternal concentration of individual fatty acids does not correlate with neonatal body weight or fat mass, but cord blood fatty acid levels correlate with birth weight and neonatal adiposity-positively in controls, but negatively in GDM. The proportion of AA and DHA in umbilical artery plasma in GDM is lower than in controls but not in umbilical vein plasma. Therefore, an increased utilization of those two fatty acids by fetal tissues, rather than impaired placental transfer, is responsible for their smaller proportion in plasma of GDM newborns. In control pregnant women, maternal glycemia controls neonatal body weight and fat mass, whereas in mothers with GDM-even with good glycemic control-maternal lipids and their greater utilization by the fetus play a critical role in neonatal body weight and fat mass. We propose that altered lipid metabolism rather than hyperglycemia constitutes a risk for macrosomia in GDM.

Osteocalcin Serum Levels in Gestational Diabetes Mellitus and Their Intrinsic and Extrinsic Determinants: Systematic Review and Meta-Analysis

BACKGROUND

Undercarboxylated osteocalcin (ucOC) increases insulin release and insulin resistance in mice. In humans, evidence is scarce but a correlation of ucOC and total osteocalcin (tOC) with glycemic status markers has been demonstrated. The relationship of ucOC and tOC with gestational diabetes mellitus (GDM) has been even less characterized.

OBJECTIVE

To assess the mean difference of tOC and ucOC serum concentrations among nondiabetic pregnant women and women diagnosed as GDM in the second trimester of pregnancy and to determine the possible intrinsic and extrinsic contributors to this difference.

METHODS

A systematic search was performed to identify relevant studies published in English and Spanish using PubMed, SCOPUS, ISI Web of Knowledge, and PROSPERO database for meta-analysis. Observational studies measuring mean serum levels of osteocalcin among GDM, with at least 10 subjects analyzed in each group were selected. Mean difference (MD) by random effects model was used. Heterogeneity between studies was assessed using Cochran's Q, H, and I ² statistics.

RESULTS

From 38 selected studies, 5 were retained for analysis for a total of 1119 pregnant women. Serum concentrations of tOC were not significantly different among women with GDM and nondiabetic pregnant controls (MD: 1.56; 95% CI: -0.70 to 3.82; p = 0.175). Meanwhile, ucOC serum levels were significantly higher among women with GDM (MD: 1.17; 95% CI: 0.24 to 2.11; p = 0.013). The only factor influencing tOC was the UV index, showing a reduction in mean difference between GDM and controls when exposed to higher concentrations of UV rays.

CONCLUSIONS

This meta-analysis provides evidence to support the use of ucOC as a potential marker for GDM rather than tOC, yielding very little variability among studies and no difference among methods or brands used for its analysis.

Postpartum screening practices, progression to abnormal glucose tolerance and its related risk factors in Asian women with a known history of gestational diabetes: A systematic review and meta-analysis

AIMS

Rate of postpartum screening and progression to glucose intolerance (diabetes and/or pre-diabetes) in Asian women with prior GDM and risk factors of diversion to abnormal glucose tolerance were reviewed.

MATERIALS AND METHODS

We searched Pub Med, Cochrane Library, Web of Science, EMBASE, and Ovid data base. About 1300 studies were screened and 27 articles were selected. Meta-analysis using Comprehensive Meta -Analysis software was conducted. All results were reported at the pooled ORs and 95% CI. Quantitative heterogeneity (I²) was assessed. To estimate the variances between studies, the statistical method "tau-squared" was applied. Statistical models like fixed effect or Mantel-Haenszel, and random effect (REM) or Dersimonian-laird were used for the analysis and integration of results.

RESULTS

Rate of glucose testing ranged from 13.1% to 81.9%. Prevalence of pre-diabetes was 3.9%-50.9%. Diabetes was reported in 2.8%-58% of women with history of gestational diabetes based on length of follow-up. Factor associated with postpartum diabetes mellitus included family History of diabetes mellitus, gestational age at diagnosis of GDM, insulin use during pregnancy and pre-pregnancy BMI.

CONCLUSIONS

Rate of postpartum screening in most of the Asian countries population is sub-optimal, in spite of high rate of glucose intolerance in this high risk group of women. Risk factors of progression to pre-diabetes and diabetes are similar to previous reported in developed countries.

High Fasting Plasma Glucose during Early Pregnancy: A Review about Early Gestational Diabetes Mellitus

Fasting plasma glucose (FPG) is nowadays routinely measured during early pregnancy to detect preexisting diabetes (FPG ≥ 7 mmol/L). This screening has concomitantly led to identify early intermediate hyperglycemia, defined as FPG in the 5.1 to 6.9 mmol/L range, also early gestational diabetes mellitus (eGDM). Early FPG has been associated with poor pregnancy outcomes, but the recommendation by the IADPSG to refer women with eGDM for immediate management is more pragmatic than evidence based. Although eGDM is characterized by insulin resistance and associated with classical risk factors for type 2 diabetes and incident diabetes after delivery, it is not necessarily associated with preexisting prediabetes. FPG ≥ 5.1 mmol/L in early pregnancy is actually poorly predictive of gestational diabetes mellitus diagnosed after 24 weeks of gestation. An alternative threshold should be determined but may vary according to ethnicity, gestational age, and body mass index. Finally, observational data suggest that early management of intermediate hyperglycemia may improve prognosis, through reduced gestational weight gain and potential early introduction of hypoglycemic agents. Considering all these issues, we suggest an algorithm for the management of eGDM based on early FPG levels that would be measured in case of risk factors. Nevertheless, interventional randomized trials are still missing.