Habitual carbohydrate intake is not correlated with circulating β-hydroxybutyrate levels in pregnant women with overweight and obesity at 28 weeks' gestation

AIMS/HYPOTHESIS

Pregnant women are advised to consume a minimum of 175 g per day of carbohydrate to meet maternal and fetal brain glucose requirements. This recommendation comes from a theoretical calculation of carbohydrate requirements in pregnancy, rather than from clinical data. This study aimed to determine whether fasting maternal ketone levels are associated with habitual carbohydrate intake in a subset of participants of the Study of PRobiotics IN Gestational diabetes (SPRING) randomised controlled trial.

METHODS

Food frequency questionnaires on dietary intake during pregnancy were completed by pregnant women with overweight or obesity at 28 weeks' gestation (considering their intake from the beginning of pregnancy). Dietary intake from early pregnancy through to 28 weeks was analysed for macronutrient intake. At the same time, overnight fasting serum samples were obtained and analysed for metabolic parameters including serum β-hydroxybutyrate, OGTTs, insulin and C-peptide.

RESULTS

Fasting serum β-hydroxybutyrate levels amongst 108 women (mean BMI 34.7 ± 6.3 kg/m2) ranged from 22.2 to 296.5 μmol/l. Median fasting β-hydroxybutyrate levels were not different between women with high (median [IQR] 68.4 [49.1-109.2 μmol/l]) and low (65.4 [43.6-138.0 μmol/l]) carbohydrate intake in pregnancy. Fasting β-hydroxybutyrate levels were not correlated with habitual carbohydrate intake (median 155 [126-189] g/day). The only metabolic parameter with which fasting β-hydroxybutyrate levels were correlated was 1 h venous plasma glucose (ρ=0.23, p=0.03) during a 75 g OGTT.

CONCLUSIONS/INTERPRETATION

Fasting serum β-hydroxybutyrate levels are not associated with habitual carbohydrate intake at 28 weeks' gestation in pregnant women with overweight and obesity.

OFFSPRING: A SPRING Follow-Up Study Assessing the Efficacy of Maternal Probiotics and Allergic Disease in the Child

INTRODUCTION

There are a variety of factors that contribute to the development of allergic diseases in children, including environmental exposures during the maternal prenatal period. It has been proposed that probiotic supplementation during pregnancy could be used as a possible preventative measure to target childhood allergic disease.

METHODS

Participants from a previously conducted prospective double-blind randomised control trial of probiotics versus placebo study (Study of PRrobiotics IN Gestation) were sent electronic questionnaires to complete about their child, who are now between 3 and 7 years of age. Demographic data and rates of allergic diseases were compared between the two groups.

RESULTS

One hundred and seven women responded to the questionnaires. Between the two groups, there was no difference in the frequency of allergic diseases, with similar rates of eczema, asthma, and hospital presentations seen.

CONCLUSION

In this follow-up study, infants of mothers who were exposed to probiotics during their pregnancy do not appear to have any paediatric health advantages in terms of allergic diseases.

Differences in neonatal adverse outcomes among women with gestational diabetes mellitus managed by diet or medication: a propensity score matched analysis of a population-based sample

OBJECTIVE

Neonatal outcomes in women with and without medically managed gestational diabetes mellitus (GDM) were compared after accounting for differences in maternal baseline characteristics using a propensity score (PS) analysis.

METHODS

Women without preexisting diabetes, delivering singletons during 2010-2017 in a large hospital, were eligible for inclusion. Using nearest-neighbour PS matching, women with non-pharmacological managed GDM were matched with women whose GDM was medically managed. A conditional logistic regression consequently compared the neonatal adverse outcomes between the groups after adjusting for gestational age, induction of labor, birth type, and number of ultrasounds conducted during the pregnancy.

RESULTS

Of the overall 10028 births, GDM was diagnosed in 930 (9.3%), of whom 710 (76.3%) were successfully matched. The conditional regressions found higher risk of neonatal adverse outcomes in neonates of women with non-pharmacological managed GDM compared to neonates of women with medically managed GDM. These included a higher risk of hypoglycemia (odds ratio (OR) 1.56, 95% confidence interval (CI) 1.03-2.38, p = 0.037), hypothermia (OR 2.29, 95%CI 1.05-5.00, p = 0.037), and birth injuries (OR 3.50, 95%CI 1.62-7.58, p = 0.001), and a higher risk of being small for gestational age (OR 2.06, 95%CI 1.01-4.18, p = 0.046) and being admitted to a special care unit (OR 2.04, 95%CI 1.29-3.21, p = 0.002).

CONCLUSIONS

The increased neonatal morbidity associated with non-medicated GDM identified in our study may indicate that diet and lifestyle changes alone are not sufficient to achieve glycaemic control in some women with GDM. Our findings indicate that gestational diabetes management approach is independently associated with neonatal outcomes.

Time trends and projections in the prevalence of gestational diabetes mellitus in Queensland, Australia, 2009-2030: Evidence from the Queensland Perinatal Data Collection

BACKGROUND

Gestational diabetes mellitus (GDM) is the fastest-growing type of diabetes in Australia. We aimed to assess the time trends during 2009-2018 and projections of GDM in Queensland, Australia up to 2030.

MATERIALS AND METHODS

The study data were from the Queensland Perinatal Data Collection (QPDC) and included data on 606 662 birth events with the births reported from at least 20 weeks gestational age or birth weight at least 400 g. Bayesian regression model was used to assess the trends in the prevalence of GDM.

RESULTS

The prevalence of GDM increased from 5.47 to 13.62% from 2009 to 2018 (average annual rate of change, AARC = +10.71%). If the trend remains the same, the projected prevalence will increase to 42.04% (95% uncertainty interval = 34.77-48.96) by 2030. Observing AARC across different subpopulations, we found that the trend of GDM increased markedly among women living in inner regional areas (AARC = +12.49%), were non-Indigenous (AARC = +10.93%), most disadvantaged (AARC = +11.84%), aged either of two age groups (AARC = +18.45% and + 15.17% for <20 years and 20-24 years, respectively), were with obesity (AARC = +11.05%) and smoked during pregnancy (AARC = +12.26%).

CONCLUSIONS

Overall, the prevalence of GDM has sharply increased in Queensland, and if this trend continues, about 42% of pregnant women will experience GDM by 2030. The trends vary across different subpopulations. Therefore, targeting the most vulnerable subpopulations is vital to prevent the development of GDM.

Applying WHO2013 diagnostic criteria for gestational diabetes mellitus reveals currently untreated women at increased risk

AIMS

To estimate the prevalence of gestational diabetes mellitus (GDM) in a Danish cohort comparing the current Danish versus the WHO2013 diagnostic criteria, and to evaluate adverse pregnancy outcomes among currently untreated women in the gap between the diagnostic thresholds.

METHODS

Diagnostic testing was performed by a 75 g oral glucose tolerance test (OGTT) at 24-28 weeks' gestation in a cohort of pregnant women. GDM diagnosis was based on the current Danish criterion (2-h glucose ≥ 9.0 mmol/L, GDMDK) and on the WHO2013 criteria (fasting ≥ 5.1, 1 h ≥ 10.0 or 2 h glucose ≥ 8.5 mmol/L, GDMWHO2013). Currently untreated women fulfilling the WHO2013 but not the Danish diagnostic criteria were defined as New-GDM-women (GDMWHO2013-positive and GDMDK-negative). Adverse outcomes risks were calculated using logistic regression.

RESULTS

OGTT was completed by 465 women at a median of 25.7 weeks' gestation. GDMDK prevalence was 2.2% (N = 10) and GDMWHO2013 21.5% (N = 100). New-GDM was present in 19.4% (N = 90), of whom 90.0% had elevated fasting glucose. Pregnancies complicated by New-GDM had higher frequencies of pregnancy-induced hypertension (13.3% vs 4.1%, p = 0.002), large-for-gestational-age infants (22.2% vs 9.9%, p = 0.004), neonatal hypoglycaemia (8.9% vs 1.9%, p = 0.004) and neonatal intensive care unit admission (16.7% vs 5.8%, p = 0.002) compared to pregnancies without GDM.

CONCLUSIONS

GDM prevalence increased tenfold when applying WHO2013 criteria in a Danish population, mainly driven by higher fasting glucose levels. Untreated GDM in the gap between the current Danish and the WHO2013 diagnostic criteria resulted in higher risks of adverse pregnancy outcomes.

Association between maternal hyperglycemia in pregnancy and offspring anthropometry in early childhood: the pandora wave 1 study

BACKGROUND

In-utero hyperglycemia exposure influences later cardiometabolic risk, although few studies include women with pre-existing type 2 diabetes (T2D) or assess maternal body mass index (BMI) as a potential confounder.

OBJECTIVE

To explore the association of maternal T2D and gestational diabetes mellitus (GDM) with childhood anthropometry, and the influence of maternal BMI on these associations.

METHODS

The PANDORA cohort comprises women (n = 1138) and children (n = 1163). Women with GDM and T2D were recruited from a hyperglycemia in pregnancy register, and women with normoglycemia from the community. Wave 1 follow-up included 423 children, aged 1.5-5 years (median follow-up age 2.5 years). Multivariable linear regression assessed associations between maternal antenatal variables, including BMI and glycemic status, with offspring anthropometry (weight, height, BMI, skinfold thicknesses, waist, arm and head circumferences).

RESULTS

Greater maternal antenatal BMI was associated with increased anthropometric measures in offspring independent of maternal glycemic status. After adjustment, including for maternal BMI, children exposed to maternal GDM had lower mean weight (-0.54 kg, 95% CI: -0.99, -0.11), BMI (-0.55 kg/m2, 95% CI: -0.91, -0.20), head (-0.52 cm, 95% CI: -0.88, -0.16) and mid-upper arm (-0.32 cm, 95% CI: -0.63, -0.01) circumferences, and greater mean suprailiac skinfold (0.78 mm, 95% CI: 0.13, 1.43), compared to children exposed to normoglycemia. Adjustment for maternal BMI strengthened the negative association between GDM and child weight, BMI and circumferences. Children exposed to maternal T2D had smaller mean head circumference (-0.82 cm, 95% CI: -1.33, -0.31) than children exposed to normoglycemia. Maternal T2D was no longer associated with greater child mean skinfolds (p = 0.14) or waist circumference (p = 0.18) after adjustment for maternal BMI.

CONCLUSIONS

Children exposed to GDM had greater suprailiac skinfold thickness than unexposed children, despite having lower mean weight, BMI and mid-upper arm circumference, and both GDM and T2D were associated with smaller mean head circumference. Future research should assess whether childhood anthropometric differences influence lifetime cardiometabolic and neurodevelopmental risk.

Trajectories of dietary patterns from pregnancy to 12 years post-pregnancy and associated maternal characteristics: evidence from the Avon Longitudinal Study of Parents and Children

PURPOSE

Dietary patterns (DPs) during pregnancy have been well researched. However, little is known about maternal diet after pregnancy. The aim of the study was to explore maternal DPs longitudinally, examine trajectories over 12 years after pregnancy and identify associated factors.

METHODS

Of 14,541 pregnant women enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC) complete dietary information was available for 5336 women. Principal components analysis (PCA) was used to derive DPs. DP scores at each time point were used to create DP trajectories using group-based trajectory modelling (GBTM). Multinomial logistic regression assessed the association with maternal factors.

RESULTS

A total of six distinct DPs were identified over time with different numbers of DPs at each time point. The "healthy" and "processed" DPs persisted over the 12-year post-pregnancy. Three trajectories of "healthy" and "processed" DPs were identified from GBTM. Half the women were on the moderately healthy DP trajectory with 37% on the lower trajectory and 9% on the higher healthy DP trajectory. 59% of women were on the lower processed DP trajectory with 38% on the moderate trajectory and 3.3% on the higher processed DP trajectory. Low educational attainment, low social class and smoking in pregnancy were independently associated with being on a less favourable DP trajectory over the 12 years.

CONCLUSION

Health professionals should provide support on smoking cessation along with healthy eating advice during ante-natal counselling. Continued support on eating healthily after pregnancy would be beneficial for mothers and families.

Adverse childhood experiences, the risk of pregnancy complications and adverse pregnancy outcomes: a systematic review and meta-analysis

BACKGROUND

Adverse childhood experiences (ACEs) have a profound negative impact on health. However, the strength of the association between ACEs and pregnancy complications and adverse pregnancy outcomes is not well quantified or understood.

OBJECTIVE

To conduct a systematic review and meta-analysis of the association between ACEs and risk of pregnancy complications and adverse pregnancy outcomes.

SEARCH STRATEGY

A comprehensive search was conducted using PubMed, Embase, CINAHL, PsycINFO, ClinicalTrials.gov and Google scholar up to July 2022.

DATA COLLECTION AND ANALYSIS

Two reviewers independently conducted the screening and quality appraisal using a validated tool. Meta-analysis using the quality-effects model on the reported odds ratio (OR) was conducted. Heterogeneity and inconsistency were examined using the I2 statistics.

RESULTS

32 studies from 1508 met a priori inclusion criteria for systematic review, with 21 included in the meta-analysis. Pooled analyses showed that exposure to ACEs increased the risk of pregnancy complications (OR 1.37, 95% CI 1.20 to 1.57) and adverse pregnancy outcomes (OR 1.31, 95% CI 1.17 to 1.47). In sub-group analysis, maternal ACEs were associated with gestational diabetes mellitus (OR 1.39, 95% CI 1.11 to 1.74), antenatal depression (OR 1.59, 95% CI 1.15 to 2.20), low offspring birth weight (OR 1.27, 95% CI 1.02 to 1.47), and preterm delivery (OR 1.41, 95% CI 1.16 to 1.71).

CONCLUSION

The results suggest that exposure to ACEs increases the risk of pregnancy complications and adverse pregnancy outcomes. Preventive strategies, screening and trauma-informed care need to be examined to improve maternal and child health.

The myth and reality of familial resemblance in dietary intake: a systematic review and meta-analysis on the resemblance of dietary intake among parent and offspring

Background

There is a strong societal belief that parents are role models for their child's dietary behaviours in early life that may persist throughout the life course. Evidence has shown inconclusive dietary resemblance in parent-child (PC) pairs. This systematic review and meta-analysis aimed to examine dietary resemblance between parent and children.

Methods

We systematically searched for studies on PC dietary resemblance, via six electronic databases (PubMed, Ovid MEDLINE, Embase, APA PsycNet, CINAHL, and Web of Science) and other grey sources of literature between 1980 and 2020. We performed quality effect meta-analysis model on transformed correlation coefficients (z) to examine the resemblance in dietary intakes including nutrient intakes, food group intakes and whole diet. Finally, the Fisher's transformed coefficient (z) was used for meta-regression analysis to identify potential moderators. Heterogeneity and inconsistency were examined using the Q and I² statistic. The study is registered on PROSPERO, CRD42019150741.

Findings

A total of 61 studies met the inclusion criteria for systematic review, 45 were included in the meta-analysis. Pooled analyses showed weak to moderate PC dietary intake associations for energy: (r: 0.19; 95% CI: 0.16, 0.22), fat (% energy): (r: 0.23; 95% CI: 0.16, 0.29), protein (% energy): (r: 0.24; 95% CI: 0.20, 0.27), carbohydrate (% energy): (r: 0.24; 95% CI: 0.19, 0.29), fruits and vegetable (g/d): (r: 0.28; 95% CI: 0.25, 0.32), confectionary food (g/d): (r: 0.20; 95% CI: 0.17, 0.23), and whole diet (r: 0.35; 95% CI: 0.28, 0.42). Dietary intakes associations by study characteristics, including population, study year, dietary assessment method, person reporting dietary intake, quality of the study, and study design were highly variable, but associations were similar between PC pairs.

Interpretation

The resemblance among parent-child pairs was weak to moderate for most aspects of dietary intakes. These findings challenge the social myth that parental dietary intake behaviour shapes their child's dietary intake.

Funding

None.

The impact of inter-laboratory glucose bias on the diagnosis of gestational diabetes mellitus: Comparison of common automated central laboratory methods

BACKGROUND AND AIMS

The diagnosis of gestational diabetes mellitus (GDM) is based exclusively on glucose measurements, which are highly influenced by pre-analytical and analytical factors. Therefore, poor agreement across laboratories may affect the prevalence of GDM. We aimed to determine the inter-laboratory bias of glucose measurements and the impact on GDM prevalence.

MATERIAL AND METHODS

A prospective cohort study of women (n=110) referred for second-trimester GDM diagnostics using a 75 g oral glucose tolerance test. Maternal glucose was assessed from venous plasma at fasting, 1 h and 2 h. Venous blood were collected in Fluoride Citrate tubes and frozen. Samples were analyzed at five central laboratories using four different automated glucose Hexokinase methods and GDM prevalence was evaluated according to WHO2013 diagnostic criteria.

RESULTS

Maximum inter-laboratory bias was 0.19, 0.30 and 0.27 mmol/L in fasting, 1 h and 2 h samples, respectively. GDM prevalence ranged 30.0-41.1% across laboratories.

CONCLUSION

Inter-laboratory bias for mean venous glucose was low and within desirable limits. Nonetheless, the impact on GDM prevalence was considerable, which may inappropriately affect clinical practice.

Regional divergence and time trends in the prevalence of gestational diabetes mellitus: a national Danish cohort study

AIMS

To evaluate the prevalence and time trends of gestational diabetes mellitus (GDM) across the five regions of Denmark with uniform national guidelines for screening and diagnosing GDM.

METHODS

This register-based national cohort study included 287,684 births from 2013 to 2017. Trends in GDM prevalence over time and differences between the five regions were evaluated. Crude and adjusted odd ratios (ORs) for GDM were calculated including potential confounding clinical risk factors as age, BMI, educational level, marital status, parity, country of origin and assisted reproduction.

RESULTS

From 2013 to 2017, GDM prevalence in Denmark increased by 7% per year (OR 1.07, 95% CI 1.06-1.09, P < 0.001). GDM prevalence varied considerably between regions and ranged from 3.0 to 5.9% in 2017, corresponding to a maximal regional difference of 97%. In crude analyses, the risk of GDM in 2017 was significantly different in four of five regions compared to the remaining regions (OR ranging from 0.60 to 1.55), and these differences persisted after adjusting for confounding clinical risk factors (adjusted OR: 0.59-1.45).

CONCLUSION

The prevalence of GDM increased over time in all Danish regions with substantial regional divergence. Up to a 97%, difference in GDM prevalence was observed between Danish regions, which was not explained by available clinical risk factors. This occurred despite national guidelines and raises the question of whether regional variations in screening efficacy, diagnostic procedures or inequality in clinical health care access may explain the observed differences.

Oral glucose tolerance test to diagnose gestational diabetes mellitus: Impact of variations in specimen handling

To improve birth outcomes, all pregnant women without known diabetes are recommended for an oral glucose tolerance test (OGTT) to screen for hyperglycaemia in pregnancy (diabetes in pregnancy or gestational diabetes mellitus (GDM)). This narrative review presents contemporary approaches to minimise preanalytical glycolysis in OGTT samples with a focus on GDM diagnosis using criteria derived from the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study. The challenges of implementing each approach across a diverse Australian healthcare setting were explored. Many Australian sites currently collect and transport OGTT samples at ambient temperature in sodium fluoride (NaF) tubes which is likely to lead to missed diagnosis of GDM in a significant proportion of cases. Alternative preanalytical solutions should be pragmatic and tailored to individual settings and as close as possible to the preanalytical conditions of the HAPO study for correct interpretation of OGTT results. Rapid centrifugation of barrier tubes to separate plasma could be suitable in urban settings provided time to centrifugation is strictly controlled. Tubes containing NaF and citrate could be useful for remote or resource poor settings with long delays to analysis but the impact on the interpretation of OGTT results should be carefully considered. Testing venous blood glucose at the point-of-care bypasses the need for glycolytic inhibition but requires careful selection of devices with robust analytical performance. Studies to evaluate the potential error of each solution compared to the HAPO protocol are required to assess the magnitude of misdiagnosis and inform clinicians regarding the potential impact on patient safety and healthcare costs.

Association between hyperglycaemia in pregnancy and growth of offspring in early childhood: The PANDORA study

BACKGROUND

Few studies have assessed whether children exposed to in utero hyperglycaemia experience different growth trajectories compared to unexposed children.

OBJECTIVES

To assess association of type 2 diabetes (T2D) and gestational diabetes mellitus (GDM) with early childhood weight, length/height and body mass index (BMI) trajectories, and with timing and magnitude of peak BMI in infancy.

METHODS

PANDORA is a birth cohort recruited from an Australian hyperglycaemia in pregnancy register, and women with normoglycaemia recruited from the community. Offspring growth measures were obtained from health records over a median follow-up of 3.0 years (interquartile range 1.9-4.0). This analysis included children born to Aboriginal mothers with in utero normoglycaemia (n = 95), GDM (n = 228) or T2D (n = 131). Growth trajectories (weight, length/height and BMI) were estimated using linear mixed models with cubic spline functions of child age.

RESULTS

After adjustment for maternal factors (age, BMI, parity, smoking, and socioeconomic measures) and child factors (age, gestational age at birth, and sex), children born to mothers with T2D or GDM had lower weight, length/height and BMI trajectories in infancy than children born to mothers with normoglycaemia, but similar weight and BMI by completion of follow-up. Children exposed to T2D had lower mean peak BMI 17.6 kg/m² (95% confidence interval [CI] 17.3-18.0) than children exposed to normoglycaemia (18.6 kg/m² [18.1-18.9]) (p = 0.001).

CONCLUSIONS

Maternal hyperglycaemia was associated with differences in early childhood growth trajectories after adjustment for maternal BMI. Exploration of associations between in utero hyperglycaemia exposure and growth trajectories into later childhood is required.

Comparing IADPSG and NICE Diagnostic Criteria for GDM in Predicting Adverse Pregnancy Outcomes

OBJECTIVE

To compare the performance of diagnostic criteria for gestational diabetes mellitus (GDM) proposed by the International Association of the Diabetes and Pregnancy Study Groups (IADPSG) with those endorsed by the National Institute for Health and Care Excellence (NICE) in predicting adverse pregnancy outcomes.

RESEARCH DESIGN AND METHODS

We performed a secondary data analysis of the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study participants in five study centers. Logistic regression analyses were performed, and Akaike information criterion were applied for the comparison of different statistical prediction models. We further analyzed the performance by four racial/ethnic subgroups, namely, Whites, Hispanics, Asians, and Blacks.

RESULTS

Among all, IADPSG criteria diagnosed 267 (4.1%) more women with GDM, but predicted primary caesarean section (CS) and large for gestational age (LGA) and neonatal adiposity better than did NICE criteria after adjustment for potential confounders. Among Whites, IADPSG criteria diagnosed 65 (2.5%) more subjects with GDM and predicted LGA and neonatal adiposity better, but predicted hypertensive disorders, primary CS and clinical neonatal hypoglycemia worse. Among Hispanics, the IADPSG criteria diagnosed 203 (12.1%) more with GDM but performed better in predicting hypertensive disorders, LGA, neonatal adiposity, and hyperinsulinemia. Among Asians, the IADPSG criteria diagnosed 34 (2.0%) fewer subjects with GDM but predicted hypertensive disorders better in the unadjusted model. In Blacks, IADPSG criteria diagnosed 34 (10.5%) more women with GDM.

CONCLUSIONS

IADPSG criteria appear to be more favorable than NICE for identification of adverse pregnancy outcomes among Hispanic and Asian women, while they are comparable to NICE among White women.

Gestational diabetes screening from the perspective of consumers: Insights from early in the COVID-19 pandemic and opportunities to optimise experiences

BACKGROUND

Consumer perspectives are a cornerstone of value-based healthcare. Screening and diagnosis of gestational diabetes mellitus (GDM) were among many of the rapid changes to health care recommended during the COVID-19 pandemic. The changes provided a unique opportunity to add information about women's perspectives on the debate on GDM screening.

AIMS

The aim of this qualitative study was to explore women's perspectives and understanding of GDM screening and diagnosis comparing the modified COVID-19 recommendations to standard GDM screening and diagnostic practices.

METHODS

Women who had experienced both the standard and modified GDM screening and diagnostic processes were recruited for telephone interviews. Data analysis used inductive reflexive thematic analysis. Online surveys were disseminated to any registrant not included in interviews to provide an opportunity for all interested participants to provide their perspective.

RESULTS

Twenty-nine telephone interviews were conducted and 19 survey responses were received. Seven themes were determined: (1) information provision from clinicians; (2) acceptability of GDM screening; (3) individualisation of GDM screening methods; (4) safety nets to avoid a missed diagnosis; (5) informed decision making; (6) women want information and evidence; and (7) preferred GDM screening methods for the future.

CONCLUSIONS

Overall, women preferred the modified GDM screening recommendations put in place due to the COVID-19 pandemic. However, their preference was influenced by their prior screening experience and perception of personal risk profile. Women expressed a strong need for clear communication from health professionals and the opportunity to be active participants in decision making.

Reduced Abundance of Nitrate-Reducing Bacteria in the Oral Microbiota of Women with Future Preeclampsia

The oral microbiota can contribute to the regulation of blood pressure by increasing the availability of nitric oxide through the reduction of nitrate to nitrite, which can be converted into nitric oxide in the stomach and then enter the circulation. It is unclear if the composition of the oral microbiota is different between women who do and do not develop preeclampsia. This study aimed to compare the composition of the buccal microbiota just prior to the development of symptoms at 36 weeks gestation in 12 women who developed late-onset preeclampsia and 24 matched women who remained normotensive throughout pregnancy by 16S rRNA gene amplicon sequencing. The abundance of the nitrate-reducing Veillonella spp V. parvula and V. dispar and a subunit of nitrate reductase narH was compared using real-time PCR. The abundance of bacteria was correlated with maternal blood pressure and dietary intake of nitrate-containing vegetables. The results showed that the abundance of nitrate-reducing bacteria including Veillonella, specifically V. parvula, and Prevotella was reduced in women who developed preeclampsia. Veillonella but not Prevotella abundance was negatively correlated with maternal blood pressure. The dietary intake of nitrate-containing vegetables did not differ between the groups and was not correlated with the abundance of Veillonella. There was no difference in the abundance of the nitrate reductase subunit narH between the groups. These results suggest that the abundance of nitrate-reducing bacteria is reduced in the oral microbiota of women who later develop preeclampsia, indicating a potential pathway for prevention.

Trends in percentages of gestational diabetes mellitus attributable to overweight, obesity, and morbid obesity in regional Victoria: an eight-year population-based panel study

Background

Gestational diabetes mellitus (GDM) is the fastest growing type of diabetes in Australia with rates trebling over the past decades partially explained by rising obesity rates and maternal age among childbearing women. Percentage of GDM attributable to obesity has been documented, mostly focusing on metropolitan populations. In parts of regional (areas outside capital cities) and rural Australia where overweight, obesity and morbid obesity are more prevalent, intertwined with socioeconomic disadvantage and higher migrant communities, trends over time in adjusted percentages of GDM attributed to obesity are unknown.

Methods

In this population-based retrospective panel study, women, without pre-existing diabetes, delivering singletons between 2010 and 2017 in a tertiary regional hospital that serves 26% of Victoria’s 6.5 million Australian population were eligible for inclusion. Secular trends in GDM by body mass index (BMI) and age were evaluated. The percentage of GDM that would have been prevented each year with the elimination of overweight or obesity was estimated using risk-adjusted regression-based population attributable fractions (AFp). Trends in the AFp over time were tested using the augmented Dickey-Fuller test.

Results

Overall 7348 women, contributing to 10,028 births were included. The age of expecting mothers, their BMI, proportion of women born overseas, and GDM incidence significantly rose over time with GDM rising from 3.5% in 2010 to 13.7% in 2017, p <  0.001, increasing in all BMI categories. The incidence was consistently highest among women with obesity (13.8%) and morbid obesity (21.6%). However, the highest relative increase was among women with BMI < 25 kg/m², rising from 1.4% in 2010 to 7.0% in 2017. Adjusting for age, country of birth, socioeconomic status, comorbidities, antenatal and intrapartum factors, an estimated 8.6% (confidence interval (CI) 6.1–11.0%), 15.6% (95% CI 12.2–19.0%), and 19.5% (95% CI 15.3–23.6%) of GDM would have been prevented by eliminating maternal overweight, obesity, and morbid obesity, respectively. However, despite the rise in obesity over time, percentages of GDM attributable to overweight, obesity, and morbid obesity significantly dropped over time. Scenario analyses supported these findings.

Conclusions

Besides increasing prevalence of obesity over time, this study suggests that GDM risk factors, other than obesity, are also increasing over time.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04420-9.

Unifying the diagnosis of gestational diabetes mellitus: Introducing the NPRP criteria

AIMS

Disagreement about the appropriate criteria for the diagnosis of gestational diabetes mellitus (GDM) persists. This study examines an alternative approach which combines information from all time-points on the glucose tolerance test (GTT) into a single index and expands the GDM spectrum into four categories using data from three geographically and ethnically distinct populations.

METHODS

A retrospective observational study design was used. Data from Wisconsin, USA (723 women) was used in derivation of the criterion and data from Doha, Qatar (1284 women) and Cape Town, South Africa (220 women) for confirmation. Pregnant women without pre-existing diabetes with a GTT done between 23 and 30 weeks gestation were included. A novel index was derived from the GTT termed the weighted average glucose (wAG). This was categorized into four pre-defined groups (henceforth National Priorities Research Program (NPRP) criterion); i) normal gestational glycemia (NGG), ii) impaired gestational glycemia (IGG), iii) GDM and iv) high risk GDM (hGDM).

RESULTS

In the Doha cohort, compared to the NGG group, the odds of large for gestational age babies increased 1.33 fold (P = 0.432), 2.86 fold (P < 0.001) and 3.35 fold (P < 0.001) in the IGG, GDM and hGDM groups respectively. The odds of pregnancy induced hypertension increased 2.10 fold (P = 0.024) in GDM & hGDM groups compared to the IGG and NGG groups. In the Cape Town cohort, a third of women in the GDM group and two-thirds in the hGDM group progressed to T2DM at 5 years.

CONCLUSIONS

The NPRP categorization identifies four distinct risk clusters of glycemia in pregnancy which may aid better decision making in routine management, avoid potential over-diagnosis of women at lower risk of complications and assist with diabetes prevention in women at high-risk after an index pregnancy with GDM.

Extracellular vesicle-associated miRNAs are an adaptive response to gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) is a serious public health issue affecting 9-15% of all pregnancies worldwide. Recently, it has been suggested that extracellular vesicles (EVs) play a role throughout gestation, including mediating a placental response to hyperglycaemia. Here, we investigated the EV-associated miRNA profile across gestation in GDM, assessed their utility in developing accurate, multivariate classification models, and determined the signaling pathways in skeletal muscle proteome associated with the changes in the EV miRNA profile.

METHODS

Discovery: A retrospective, case-control study design was used to identify EV-associated miRNAs that vary across pregnancy and clinical status (i.e. GDM or Normal Glucose Tolerance, NGT). EVs were isolated from maternal plasma obtained at early, mid and late gestation (n = 29) and small RNA sequencing was performed. Validation: A longitudinal study design was used to quantify expression of selected miRNAs. EV miRNAs were quantified by real-time PCR (cases = 8, control = 14, samples at three times during pregnancy) and their individual and combined classification efficiencies were evaluated. Quantitative, data-independent acquisition mass spectrometry was use to establish the protein profile in skeletal muscle biopsies from normal and GDM.

RESULTS

A total of 2822 miRNAs were analyzed using a small RNA library, and a total of 563 miRNAs that significantly changed (p < 0.05) across gestation and 101 miRNAs were significantly changed between NGT and GDM. Analysis of the miRNA changes in NGT and GDM separately identified a total of 256 (NGT-group), and 302 (GDM-group) miRNAs that change across gestation. A multivariate classification model was developed, based on the quantitative expression of EV-associated miRNAs, and the accuracy to correctly assign samples was > 90%. We identified a set of proteins in skeletal muscle biopsies from women with GDM associated with JAK-STAT signaling which could be targeted by the miRNA-92a-3p within circulating EVs. Interestingly, overexpression of miRNA-92a-3p in primary skeletal muscle cells increase insulin-stimulated glucose uptake.

CONCLUSIONS

During early pregnancy, differently-expressed, EV-associated miRNAs may be of clinical utility in identifying presymptomatic women who will subsequently develop GDM later in gestation. We suggest that miRNA-92a-3p within EVs might be a protected mechanism to increase skeletal muscle insulin sensitivity in GDM.

The association of general obesity, central obesity and visceral body fat with the risk of gestational diabetes mellitus: Evidence from a systematic review and meta-analysis

BACKGROUND

Studies consistently reported that general obesity predicts gestational diabetes mellitus (GDM). However, whether other phenotypes of obesity such as central obesity and visceral adiposity might have differential associations as risk factors of GDM are less known. The objective of this study was to investigate the association of all these obesity phenotypes in developing GDM.

METHODS

PubMed, CINHAL, Embase, Scopus, Google Scholar and Web of Science were searched. Full-text research articles published in English from 1985 to February 2020 with cohort and cross-sectional studies design and reported an association between obesity and GDM were included. Case-control studies, case reports, conference abstract, women with previous metabolic disorders and articles considered general obesity only were excluded. A bias adjusted-quality effect meta-analysis was conducted to evaluate the association of these obesity phenotypes and GDM risk.

RESULTS

Twenty studies met the inclusion criteria representing data of ∼50 thousand women at the reproductive age with ∼7% prevalence of GDM. Meta-analysis of 14 datasets revealed that the three types of obesity were significantly associated with an increased risk of GDM. In addition, visceral adiposity was a stronger risk factor for GDM than other obesity phenotypes (odd ratio = 3.25, 95% confidence interval = 2.01-5.26) versus (odd ratio = 2.73, 95% confidence interval = 2.20-3.38) for general obesity and (odd ratio = 2.53, 95% confidence interval = 2.04-3.14) for central obesity.

CONCLUSION

The findings of this study suggest that general obesity, central obesity and visceral body fat were associated with an increased risk of GDM. Furthermore, the association with maternal visceral adiposity was more robust compared to general obesity and central obesity.

Prediction of large-for-gestational age infants in relation to hyperglycemia in pregnancy - A comparison of statistical models

AIMS

Using data from a large multi-centre cohort, we aimed to create a risk prediction model for large-for-gestational age (LGA) infants, using both logistic regression and naïve Bayes approaches, and compare the utility of these two approaches.

METHODS

We have compared the two techniques underpinning machine learning: logistic regression (LR) and naïve Bayes (NB) in terms of their ability to predict large-for-gestational age (LGA) infants. Using data from five centres involved in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study, we developed LR and NB models and compared the predictive ability and stability between the models. Models were developed combining the risks of hyperglycaemia (assessed in three forms: IADPSG GDM yes/no, GDM subtype, OGTT z-score quintiles), demographic and clinical variables as potential predictors.

RESULTS

The two approaches resulted in similar estimates of LGA risk (intraclass correlation coefficient 0.955, 95% CI 0.952, 0.958) however the AUROC for the LR model was significantly higher (0.698 vs 0.682; p < 0.001). When comparing the three LR models, use of individual OGTT z-score quintiles resulted in statistically higher AUROCs than the other two models.

CONCLUSIONS

Logistic regression can be used with confidence to assess the relationship between clinical and biochemical variables and outcome.

Improving systems of prenatal and postpartum care for hyperglycemia in pregnancy: A process evaluation

OBJECTIVE

To identify successes to date and opportunities for improvement in the implementation of a complex health systems intervention aiming to improve prenatal and postpartum care and health outcomes for women with hyperglycemia in pregnancy in regional and remote Australia.

METHODS

A qualitative evaluation, underpinned by the RE-AIM framework (reach, effectiveness, adoption, implementation, maintenance), was conducted mid-intervention. Semi-structured interviews were conducted with the participants, who included clinicians, regional policymakers and managers, and study implementation staff.

RESULTS

Interviewees (n = 45) reported that the early phase of the intervention had resulted in the establishment of a clinician network, increased clinician awareness of hyperglycemia in pregnancy, and improvements in management, including earlier referral for specialist care and a focus on improving communication with women. Enablers of implementation included existing relationships with stakeholders and alignment of the intervention with health service priorities. Challenges included engaging remote clinicians and the labor-intensive nature of maintaining a clinical register of women with hyperglycemia in pregnancy.

CONCLUSION

The early phase of this health systems intervention has had a positive perceived impact on systems of care for women with hyperglycemia in pregnancy. Findings have informed modifications to the intervention, including the development of a communication and engagement strategy.

Maternal gut microbiota displays minor changes in overweight and obese women with GDM

BACKGROUND AND AIMS

Previous literature have shown a diversity of findings regarding the relationship between the maternal gut microbiota and gestational diabetes mellitus (GDM). We investigated the gut microbiota of overweight and obese women with gestational diabetes mellitus (GDM) against matched euglycaemic women at 16 and 28-weeks' gestation.

METHODS AND RESULTS

This study included women from the SPRING (Study of PRobiotics IN Gestational diabetes) cohort. Overweight and obese women with no impaired glucose tolerance or impaired fasted glucose were enrolled prior to gestational age <16 weeks. Participants with a diagnosis of GDM (n = 29) were matched with euglycaemic (n = 29) women for body mass index, probiotic or placebo intervention, maternal age, parity and ethnicity. Anthropometric, clinical and fecal microbiota (16S rRNA amplicon-based sequencing of V6-V8 region) data was assessed at 16 and 28-weeks' gestation. The relative abundances of key bacterial genera were not significantly altered between euglycaemic women and women with GDM. Occurrence of bacterial taxa was similar between groups at both timepoints. GDM was associated with decreased Shannon diversity (p = 0.02) without differentiated clustering measured by beta diversity at 28-weeks' gestation.

CONCLUSIONS

Overweight and obese women with GDM demonstrate minor variation in the gut microbiota at 16 and 28-weeks' gestation compared with matched euglycaemic women. This study expands on previous literature concluding the microbiota does not likely have a disease-specific characterisation in GDM.

FIGO (international Federation of Gynecology and obstetrics) initiative on fetal growth: best practice advice for screening, diagnosis, and management of fetal growth restriction

Fetal growth restriction (FGR) is defined as the failure of the fetus to meet its growth potential due to a pathological factor, most commonly placental dysfunction. Worldwide, FGR is a leading cause of stillbirth, neonatal mortality, and short- and long-term morbidity. Ongoing advances in clinical care, especially in definitions, diagnosis, and management of FGR, require efforts to effectively translate these changes to the wide range of obstetric care providers. This article highlights agreements based on current research in the diagnosis and management of FGR, and the areas that need more research to provide further clarification of recommendations. The purpose of this article is to provide a comprehensive summary of available evidence along with practical recommendations concerning the care of pregnancies at risk of or complicated by FGR, with the overall goal to decrease the risk of stillbirth and neonatal mortality and morbidity associated with this condition. To achieve these goals, FIGO (the International Federation of Gynecology and Obstetrics) brought together international experts to review and summarize current knowledge of FGR. This summary is directed at multiple stakeholders, including healthcare providers, healthcare delivery organizations and providers, FIGO member societies, and professional organizations. Recognizing the variation in the resources and expertise available for the management of FGR in different countries or regions, this article attempts to take into consideration the unique aspects of antenatal care in low-resource settings (labelled “LRS” in the recommendations). This was achieved by collaboration with authors and FIGO member societies from low-resource settings such as India, Sub-Saharan Africa, the Middle East, and Latin America.

Adapting fasting plasma glucose threshold for GDM diagnosis according to the population distribution - An approach to the Danish paradox

AIMS

To examine third trimester fasting venous plasma glucose (FVPG) according to the distribution of a Danish population of pregnant women and identify potential local FVPG thresholds for GDM diagnosis related to risks of adverse pregnancy outcomes.

METHODS

In the observational Odense Child Cohort (OCC) study, 1516 women had FVPG measured at 27-28 weeks' gestation and were considered normal by Danish criteria and remained untreated. Maternal FVPG from OCC were standardized according to the local FVPG mean and standard deviation calibrated to data from the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study. Associations between maternal FVPG and clinical and anthropometric outcomes were analysed. Potential FVPG cut points were identified.

RESULTS

Unadjusted areas under the ROC curve for FVPG to discriminate for large for gestational age (LGA) and hypertensive disorders of pregnancy were 0.61 (95% CI 0.56, 0.67) and 0.57 (95% CI 0.52, 0.63), respectively. The Youden FVPG cut point for LGA was 5.5 mmol/L and 5.0 mmol/L for hypertensive disorders of pregnancy.

CONCLUSIONS

This study identified a potential locally appropriate third trimester FVPG cut point between 5.5 and 5.7 mmol/L based on LGA risk in pregnancy. This cut point should be validated prospectively in other Danish cohorts.

Capillary Triglycerides in Late Pregnancy-Challenging to Measure, Hard to Interpret: A Cohort Study of Practicality

BACKGROUND

Maternal triglycerides are increasingly recognised as important predictors of infant growth and fat mass. The variability of triglyceride patterns during the day and their relationship to dietary intake in women in late pregnancy have not been explored. This prospective cohort study aimed to examine the utility of monitoring capillary triglycerides in women in late pregnancy.

METHODS

Twenty-nine women (22 with gestational diabetes (GDM) and 7 without) measured capillary glucose and triglycerides using standard meters at home for four days. On two of those days, they consumed one of two standard isocaloric breakfast meals: a high-fat/low-carbohydrate meal (66% fat) or low fat/high carbohydrate meal (10% fat). Following the standard meals, glucose and triglyceride levels were monitored.

RESULTS

Median capillary triglycerides were highly variable between women but did not differ between GDM and normoglycaemic women. There was variability in capillary triglycerides over four days of home monitoring and a difference in incremental area under the curve for capillary triglycerides and glucose between the two standard meals. The high-fat standard meal lowered the incremental area under the curve for capillary glucose (p < 0.0001). Fasting (rho 0.66, p = 0.0002) and postpradial capillary triglycerides measured at home correlated with venous triglyceride levels.

CONCLUSIONS

The lack of differences in response to dietary fat intake and the correlation between capillary and venous triglycerides suggest that monitoring of capillary triglycerides before and after meals in pregnancy is unlikely to be useful in the routine clinical practice management of women with gestational diabetes mellitus.

Extracellular vesicles and their potential role inducing changes in maternal insulin sensitivity during gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is one of the most common endocrine disorders during gestation and affects around 15% of all pregnancies worldwide, paralleling the global increase in obesity and type 2 diabetes. Normal pregnancies are critically dependent on the development of maternal insulin resistance balanced by an increased capacity to secrete insulin, which allows for the allocation of nutrients for adequate foetal growth and development. Several factors including placental hormones, inflammatory mediators and nutrients have been proposed to alter insulin sensitivity and insulin response and underpin the pathological outcomes of GDM. However, other factors may also be involved in the regulation of maternal metabolism and a complete understanding of GDM pathophysiology requires the identification of these factors, and the mechanisms associated with them. Recent studies highlight the potential utility of tissue-specific extracellular vesicles (EVs) in the diagnosis of disease onset and treatment monitoring for several pregnancy-related complications, including GDM. To date, there is a paucity of data defining changes in the release, content, bioactivity and diagnostic utility of circulating EVs in pregnancies complicated by GDM. Placental EVs may engage in paracellular interactions including local cell-to-cell communication between the cell constituents of the placenta and contiguous maternal tissues, and/or distal interactions involving the release of placental EVs into biological fluids and their transport to a remote site of action. Hence, the aim of this review is to discuss the biogenesis, isolation methods and role of EVs in the physiopathology of GDM, including changes in maternal insulin sensitivity during pregnancy.

Do variations in insulin sensitivity and insulin secretion in pregnancy predict differences in obstetric and neonatal outcomes?

AIMS/HYPOTHESIS

Gestational diabetes mellitus (GDM) is generally defined based on glycaemia during an OGTT, but aetiologically includes women with defects in insulin secretion, insulin sensitivity or a combination of both. In this observational study, we aimed to determine if underlying pathophysiological defects evaluated as continuous variables predict the risk of important obstetric and neonatal outcomes better than the previously used dichotomised or categorical approaches.

METHODS

Using data from blinded OGTTs at mean gestational week 28 from five Hyperglycemia and Adverse Pregnancy Outcome study centres, we estimated insulin secretion (Stumvoll first phase) and sensitivity (Matsuda index) and their product (oral disposition index [DI]) in 6337 untreated women (1090 [17.2%] with GDM as defined by the International Association of Diabetes and Pregnancy Study Groups). Rather than dichotomising these variables (i.e. GDM yes/no) or subtyping by insulin impairment, we related insulin secretion and sensitivity as continuous variables, along with other maternal characteristics, to obstetric and neonatal outcomes using multiple regression and receiver operating characteristic curve analysis.

RESULTS

Stratifying by GDM subtype offered superior prediction to GDM yes/no only for neonatal hyperinsulinaemia and pregnancy-related hypertension. Including the DI and the Matsuda score significantly increased the area under the receiver operating characteristic curve (AUROC) and improved prediction for multiple outcomes (large for gestational age [AUROC 0.632], neonatal adiposity [AUROC 0.630], pregnancy-related hypertension [AUROC 0.669] and neonatal hyperinsulinaemia [AUROC 0.688]). Neonatal hypoglycaemia was poorly predicted by all models. Combining the DI and the Matsuda score with maternal characteristics substantially improved the predictive power of the model for large for gestational age, neonatal adiposity and pregnancy-related hypertension.

CONCLUSION/INTERPRETATION

Continuous measurement of insulin secretion and insulin sensitivity combined with basic clinical variables appeared to be superior to GDM (yes/no) or subtyping by insulin secretion and/or sensitivity impairment in predicting obstetric and neonatal outcomes in a multi-ethnic cohort. Graphical abstract.

A Review of the Current Status of Gestational Diabetes Mellitus in Australia-The Clinical Impact of Changing Population Demographics and Diagnostic Criteria on Prevalence

The current status of gestational diabetes mellitus in Australia reveals an almost quadrupling prevalence over the last decade. A narrative review of the current Australian literature reveals unique challenges faced by Australian maternity clinicians when addressing this substantial disease burden in our diverse population. Rising rates of maternal overweight and obesity, increasing maternal age and the diversity of ethnicity are key epidemiological impactors, overlaid by the 2015 changes in screening and diagnostic parameters. Our vast land mass and the remote location of many at risk women requires innovative and novel ideas for pathways to diagnose and effectively manage women with gestational diabetes mellitus. By modifying and modernizing models of care for women with gestational diabetes mellitus, we have the ability to address accessibility, resource management and our acute response to global events such as the COVID 19 pandemic. With continuing research, education and robust discourse, Australia is well placed to meet current and future challenges in the management of gestational diabetes mellitus.

Development of the Birthweight Appropriateness Quotient: A New Measure of Infant's Size

INTRODUCTION

The customised birthweight model can be used to improve detection of babies that may be at risk of adverse outcomes associated with abnormal growth, however it is currently used in conjunction with either an intrauterine growth standard or the individualised birthweight ratio (IBR), both of which have significant methodological flaws. Our aim was to investigate the statistical validity of the IBR and attempt to develop a new measurement to represent the appropriateness of an infant's size at birth that will support clinicians in identifying infants requiring further attention.

METHODS

Routinely collected hospital maternity and neonatal data on singleton, term births from a tertiary Australian hospital were extracted for the time period 1998-2009. The relationships between birthweight, customised birthweight and IBR are investigated using correlation, regression analysis and division of births into groups of < 2500 g, 2500-4000 g and > 4000 g. A new measure, the Birthweight Appropriateness Quotient (BAQ), is developed. The utility of the BAQ is compared with IBR and birthweight to identify infants with a composite neonatal morbidity outcome.

RESULTS

Statistical flaws with the IBR due to significant correlation between birthweight and customised birthweight and a heterogenous relationship between these two measurements across the range of birthweight are present. BAQ is uncorrelated with birthweight. Comparison of BAQ and IBR as indicators of adverse neonatal outcome demonstrates that BAQ identifies babies at risk due to their small size and those babies at risk due to inappropriate size.

CONCLUSIONS FOR PRACTICE

BAQ is a customised measurement of an infant's size free of the statistical flaws experienced by the IBR with the ability to identify at-risk infants.

ADIPS 2020 guideline for pre-existing diabetes and pregnancy

This is the full version of the Australasian Diabetes in Pregnancy Society (ADIPS) 2020 guideline for pre-existing diabetes and pregnancy. The guideline encompasses the management of women with pre-existing type 1 diabetes and type 2 diabetes in relation to pregnancy, including preconception, antepartum, intrapartum and postpartum care. The management of women with monogenic diabetes or cystic fibrosis-related diabetes in relation to pregnancy is also discussed.

Role of maternal glucose metabolism in the association between maternal BMI and neonatal size and adiposity

BACKGROUND/OBJECTIVE

One potential mechanism by which maternal obesity impacts fetal growth is through hyperglycemia below the threshold for gestational diabetes. Data regarding which measures of maternal glucose metabolism mediate this association is sparse. The objectives of this study were to (i) quantify the associations of maternal pre-pregnancy body mass index (BMI) with neonatal size and adiposity and (ii) examine the role of markers of maternal glucose metabolism as mediators in these associations.

SUBJECTS/METHODS

This is a secondary analysis of 6,379 mother-infant dyads from the Hyperglycemia and Adverse Pregnancy Outcome cohort. Markers of glucose metabolism, including plasma glucose and c-peptide values, Stumvoll first-phase estimate, modified Matsuda index, and oral disposition index were measured and calculated from an oral glucose tolerance test (OGTT) between 24- and 32-weeks' gestation. We calculated the direct effect of maternal BMI category, measured at the time of the OGTT and regressed to estimate pre-pregnancy BMI, on neonatal (1) birth weight (BW), (2) fat mass (FM), (3) % body fat (BF%), and (4) sum of skinfold thickness (sSFT). We then calculated the indirect effect of BMI category on these measures through markers of glucose metabolism.

RESULTS

Maternal BMI category was positively associated with neonatal BW, FM, BF%, and sSFT. Additionally, mothers who were overweight or obese had higher odds of delivering an infant with BW, FM, BF%, or sSFT >90th percentile. Fasting glucose and c-peptide values were the strongest mediators in the linear associations between maternal BMI category and neonatal size and adiposity.

CONCLUSIONS

Maternal overweight and obesity were associated with higher odds of neonatal BW and adiposity >90th percentile. Fasting measures of glucose metabolism were the strongest mediators of these associations, suggesting that future studies should investigate whether incorporation of these markers in pregnant women with obesity may improve prediction of neonatal size and adiposity.

Metformin in women with type 2 diabetes in pregnancy (MiTy): a multicentre, international, randomised, placebo-controlled trial

BACKGROUND

Although metformin is increasingly being used in women with type 2 diabetes during pregnancy, little data exist on the benefits and harms of metformin use on pregnancy outcomes in these women. We aimed to investigate the effects of the addition of metformin to a standard regimen of insulin on neonatal morbidity and mortality in pregnant women with type 2 diabetes.

METHODS

In this prospective, multicentre, international, randomised, parallel, double-masked, placebo-controlled trial, women with type 2 diabetes during pregnancy were randomly assigned from 25 centres in Canada and four in Australia to receive either metformin 1000 mg twice daily or placebo, added to insulin. Randomisation was done via a web-based computerised randomisation service and stratified by centre and pre-pregnancy BMI (<30 kg/m² or ≥30 kg/m²) in a ratio of 1:1 using random block sizes of 4 and 6. Women were eligible if they had type 2 diabetes, were on insulin, had a singleton viable pregnancy, and were between 6 and 22 weeks plus 6 days' gestation. Participants were asked to check their fasting blood glucose level before the first meal of the day, before the last meal of the day, and 2 h after each meal. Insulin doses were adjusted aiming for identical glucose targets (fasting glucose <5·3 mmol/L [95 mg/dL], 2-h postprandial glucose <6·7 mmol/L [120 mg/dL]). Study visits were done monthly and patients were seen every 1-4 weeks as was needed for standard clinical care. At study visits blood pressure and bodyweight were measured; patients were asked about tolerance to their pills, any hospitalisations, insulin doses, and severe hypoglycaemia events; and glucometer readings were downloaded to the central coordinating centre. Participants, caregivers, and outcome assessors were masked to the intervention. The primary outcome was a composite of fetal and neonatal outcomes, for which we calculated the relative risk and 95% CI between groups, stratifying by site and BMI using a log-binomial regression model with an intention-to-treat analysis. Secondary outcomes included several relevant maternal and neonatal outcomes. The trial was registered with ClinicalTrials.gov, NCT01353391.

FINDINGS

Between May 25, 2011, and Oct 11, 2018, we randomly assigned 502 women, 253 (50%) to metformin and 249 (50%) to placebo. Complete data were available for 233 (92%) participants in the metformin group and 240 (96%) in the placebo group for the primary outcome. We found no significant difference in the primary composite neonatal outcome between the two groups (40% vs 40%; p=0·86; relative risk [RR] 1·02 [0·83 to 1·26]). Compared with women in the placebo group, metformin-treated women achieved better glycaemic control (HbA_1c at 34 weeks' gestation 41·0 mmol/mol [SD 8·5] vs 43·2 mmol/mol [-10]; 5·90% vs 6·10%; p=0·015; mean glucose 6·05 [0·93] vs 6·27 [0·90]; difference -0·2 [-0·4 to 0·0]), required less insulin (1·1 units per kg per day vs 1·5 units per kg per day; difference -0·4 [95% CI -0·5 to -0·2]; p<0·0001), gained less weight (7·2 kg vs 9·0 kg; difference -1·8 [-2·7 to -0·9]; p<0·0001) and had fewer caesarean births (125 [53%] of 234 in the metformin group vs 148 [63%] of 236 in the placebo group; relative risk [RR] 0·85 [95% CI 0·73 to 0·99]; p=0·031). We found no significant difference between the groups in hypertensive disorders (55 [23%] in the metformin group vs 56 [23%] in the placebo group; p=0·93; RR 0·99 [0·72 to 1·35]). Compared with those in the placebo group, metformin-exposed infants weighed less (mean birthweight 3156 g [SD 742] vs 3375 g [742]; difference -218 [-353 to -82]; p=0·002), fewer were above the 97th centile for birthweight (20 [9%] in the metformin group vs 34 [15%] in the placebo group; RR 0·58 [0·34 to 0·97]; p=0·041), fewer weighed 4000 g or more at birth (28 [12%] in the metformin group vs 44 [19%] in the placebo group; RR 0·65 [0·43 to 0·99]; p=0·046), and metformin-exposed infants had reduced adiposity measures (mean sum of skinfolds 16·0 mm [SD 5·0] vs 17·4 [6·2] mm; difference -1·41 [-2·6 to -0·2]; p=0·024; mean neonatal fat mass 13·2 [SD 6·2] vs 14·6 [5·0]; p=0·017). 30 (13%) infants in the metformin group and 15 (7%) in the placebo group were small for gestational age (RR 1·96 [1·10 to 3·64]; p=0·026). We found no significant difference in the cord c-peptide between groups (673 pmol/L [435] in the metformin group vs 758 pmol/L [595] in the placebo group; p=0·10; ratio of means 0·88 [0·72 to 1·02]). The most common adverse event reported was gastrointestinal (38 events in the metformin group and 38 events in the placebo group).

INTERPRETATION

We found several maternal glycaemic and neonatal adiposity benefits in the metformin group. Along with reduced maternal weight gain and insulin dosage and improved glycaemic control, the lower adiposity and infant size measurements resulted in fewer large infants but a higher proportion of small-for-gestational-age infants. Understanding the implications of these effects on infants will be important to properly advise patients who are contemplating the use of metformin during pregnancy.

FUNDING

Canadian Institutes of Health Research, Lunenfeld-Tanenbaum Research Institute, University of Toronto.

Testing for gestational diabetes during the COVID-19 pandemic. An evaluation of proposed protocols for the United Kingdom, Canada and Australia

AIMS

We assessed how altered diagnostic processes and criteria for gestational diabetes mellitus (GDM) recommended by the United Kingdom (UK), Canada and Australia for use during the COVID-19 pandemic would affect both GDM frequency and related adverse outcomes.

METHODS

Secondary analysis of 5974 HAPO study women with singleton pregnancies who underwent 75 g OGTTs and HbA1c assays between 24 and 32 weeks' gestation and who received no treatment for GDM.

RESULTS

All post COVID-19 modified pathways reduced GDM frequency - UK (81%), Canada (82%) and Australia (25%). Canadian women whose GDM would remain undetected post COVID-19 (missed GDMs) displayed similar rates of pregnancy complications to those with post COVID-19 GDM. Using UK modifications, the missed GDM group were at slightly lower risk whilst the women missed using the Australian modifications were at substantially lower risk.

CONCLUSIONS

The modifications in GDM diagnosis proposed for the UK, Canada and Australia result in differing reductions of GDM frequency. Each has both potential benefits in terms of reduction in potential exposure to COVID-19 and costs in terms of missed opportunities to influence pregnancy and postpartum outcomes. These factors should be considered when deciding which protocol is most appropriate for a particular context.

Prevention of noncommunicable diseases by interventions in the preconception period: A FIGO position paper for action by healthcare practitioners

With the increase in obesity prevalence among women of reproductive age globally, the risks of type 2 diabetes, gestational diabetes, pre-eclampsia, and other conditions are rising, with detrimental effects on maternal and newborn health. The period before pregnancy is increasingly recognized as crucial for addressing weight management and reducing malnutrition (both under- and overnutrition) in both parents to reduce the risk of noncommunicable diseases (NCDs) in the mother as well as the passage of risk to her offspring. Healthcare practitioners, including obstetricians, gynecologists, midwives, and general practitioners, have an important role to play in supporting women in planning a pregnancy and achieving healthy nutrition and weight before pregnancy. In this position paper, the FIGO Pregnancy Obesity and Nutrition Initiative provides an overview of the evidence for preconception clinical guidelines to reduce the risk of NCDs in mothers and their offspring. It encourages healthcare practitioners to initiate a dialogue on women's health, nutrition, and weight management before conception. While acknowledging the fundamental importance of the wider social and environmental determinants of health, this paper focuses on a simple set of recommendations for clinical practice that can be used even in short consultations. The recommendations can be contextualized based on local cultural and dietary practices as part of a system-wide public health approach to influence the wider determinants as well as individual factors influencing preconception health.

Diagnosing and providing initial management for patients with Gestational Diabetes: What is the General Practitioner's experience?

AIM

This study explores the General Practice (GP) experience of Gestational Diabetes Mellitus (GDM). Much has been written about patient perspectives, yet little is known about the GP perspective at initial diagnosis and management. GDM is increasingly managed in the secondary and tertiary sector, the confidence of GPs and their role in ongoing care has not been examined. Given GDM's poor follow up rates, all aspects of the patient journey warrant close examination.

METHODS

Through purposive and snowball sampling, we conducted semi-structured interviews with GPs in Brisbane, Australia between April and October 2018. Data collection, until saturation, and analysis were concurrent, and the Leximancer analysis tool assisted with content analysis and suggestion of themes.

RESULTS

Dominant themes include uncertainty/urgency and feeling under-utilised. GPs have a pragmatic approach in the face of uncertainty, and adopt one of several strategies to meet patient needs. A key issue that may impact on long term follow up and high quality GP-patient relationships is concern about the patient being 'taken away' by the hospital. Communication with the hospital is generally perceived as poor.

CONCLUSIONS

The experience of GPs in the initial diagnosis and management of GDM may assist in improving GDM follow up.

Global interim guidance on coronavirus disease 2019 (COVID-19) during pregnancy and puerperium from FIGO and allied partners: Information for healthcare professionals

In response to the World Health Organization (WHO) statements and international concerns regarding the coronavirus disease 2019 (COVID‐19) outbreak, FIGO has issued comprehensive guidance for the management of pregnant women.

Social and economic factors, maternal behaviours in pregnancy and neonatal adiposity in the PANDORA cohort

BACKGROUND

Australian Indigenous women experience high rates of social disadvantage and type 2 diabetes (T2D) in pregnancy, but it is not known how social factors and maternal behaviours impact neonatal adiposity in offspring of women with hyperglycaemia in pregnancy.

METHODS

Participants were Indigenous (n = 404) and Europid (n = 240) women with gestational diabetes mellitus (GDM) or T2D in pregnancy and their offspring in the Pregnancy and Neonatal Diabetes Outcomes in Remote Australia (PANDORA) study. Social, economic factors, and maternal behaviours were measured in pregnancy and six neonatal anthropometric outcomes were examined after birth.

RESULTS

On univariate analysis, maternal education < 12 years (p = 0.03), unemployment (p = 0.001), welfare income vs no welfare income (p = 0.001), lower area based socio-economic score (p < 0.001), and fast food intake > 2 times/week (p = 0.002) were associated with increased sum of skinfolds (SSF) in offspring. Smoking was significantly associated with a reduction in anthropometric measures, except SSF. In multivariable models adjusted for ethnicity, BMI and hyperglycaemia, social and economic factors were no longer significant predictors of neonatal outcomes. Smoking was independently associated with a reduction in length, head circumference and fat free mass. Frequent fast food intake remained independently associated with SSF (β-coefficient 1.08 mm, p = 0.02).

CONCLUSION

In women with hyperglycaemia in pregnancy, social factors were associated with neonatal adiposity, particularly skinfold measures. Promoting smoking cessation and limited intake of energy-dense, nutrient-poor foods in pregnancy are important to improve neonatal adiposity and lean mass outcomes. Addressing inequities in social and economic factors are likely to be important, particularly for Indigenous women or women experiencing social disadvantage.

Cord blood metabolic markers are strong mediators of the effect of maternal adiposity on fetal growth in pregnancies across the glucose tolerance spectrum: the PANDORA study

AIMS/HYPOTHESIS

We aimed to assess associations between cord blood metabolic markers and fetal overgrowth, and whether cord markers mediated the impact of maternal adiposity on neonatal anthropometric outcomes among children born to Indigenous and Non-Indigenous Australian women with normal glucose tolerance (NGT), gestational diabetes mellitus (GDM) and pregestational type 2 diabetes mellitus.

METHODS

From the Pregnancy and Neonatal Outcomes in Remote Australia (PANDORA) study, an observational cohort of 1135 mother-baby pairs, venous cord blood was available for 645 singleton babies (49% Indigenous Australian) of women with NGT (n = 129), GDM (n = 419) and type 2 diabetes (n = 97). Cord glucose, triacylglycerol, HDL-cholesterol, C-reactive protein (CRP) and C-peptide were measured. Multivariable logistic and linear regression were used to assess the associations between cord blood metabolic markers and the outcomes of birthweight z score, sum of skinfold thickness (SSF), being large for gestational age (LGA) and percentage of body fat. Pathway analysis assessed whether cord markers mediated the associations between maternal and neonatal adiposity.

RESULTS

Elevated cord C-peptide was significantly associated with increasing birthweight z score (β 0.57 [95% CI 0.42, 0.71]), SSF (β 0.83 [95% CI 0.41, 1.25]), percentage of body fat (β 1.20 [95% CI 0.69, 1.71]) and risk for LGA [OR 3.14 [95% CI 2.11, 4.68]), after adjusting for age, ethnicity and diabetes type. Cord triacylglycerol was negatively associated with birthweight z score for Indigenous Australian women only. No associations between cord glucose, HDL-cholesterol and CRP >0.3 mg/l (2.9 nmol/l) with neonatal outcomes were observed. C-peptide mediated 18% (95% CI 13, 36) of the association of maternal BMI with LGA and 11% (95% CI 8, 17) of the association with per cent neonatal fat.

CONCLUSIONS/INTERPRETATION

Cord blood C-peptide is an important mediator of the association between maternal and infant adiposity, across the spectrum of maternal glucose tolerance.

Gestational Diabetes Mellitus-Innovative Approach to Prediction, Diagnosis, Management, and Prevention of Future NCD-Mother and Offspring

Gestational diabetes mellitus (GDM) is the commonest medical complication of pregnancy. The association of GDM with immediate pregnancy complications including excess fetal growth and adiposity with subsequent risk of birth trauma and with hypertensive disorders of pregnancy is well recognized. However, the associations with wide ranges of longer-term health outcomes for mother and baby, including the lifetime risks of obesity, pre-diabetes, and diabetes and cardiovascular disease have received less attention and few health systems address these important issues in a systematic way. This article reviews historical and recent data regarding prediction of GDM using demographic, clinical, and biochemical parameters. We evaluate current and potential future diagnostic approaches designed to most effectively identify GDM and extend this analysis into a critical evaluation of lifestyle and nutritional/pharmacologic interventions designed to prevent the development of GDM. The general approach to management of GDM during pregnancy is then discussed and the major final focus of the article revolves around the importance of a GDM diagnosis as a future marker of the risk of non-communicable disease (NCD), in particular pre-diabetes, diabetes, and cardiovascular disease, both in mother and offspring.

Birth outcomes in women with gestational diabetes managed by lifestyle modification alone: The PANDORA study

AIMS

To assess outcomes of women in the Pregnancy and Neonatal Diabetes Outcomes in Remote Australia (PANDORA) cohort with gestational diabetes mellitus (GDM) managed by lifestyle modification compared with women without hyperglycaemia in pregnancy.

METHODS

Indigenous (n = 97) and Europid (n = 113) women managed by lifestyle modification were compared to women without hyperglycaemia (n = 235). Multivariate linear and logistic regressions assessed whether GDM-lifestyle women had poorer outcomes compared to women without hyperglycaemia.

RESULTS

Women with GDM-lifestyle had higher body mass index and lower gestational weight gain than women without hyperglycaemia. On univariate analysis, gestational age at delivery was lower and induction rates were higher in women with GDM-lifestyle than without hyperglycaemia. On multivariable regression, GDM-lifestyle was associated with lower gestational age at delivery (by 0.73 weeks), lower birthweight z-score (by 0.26, p = 0.007), lower likelihood of large for gestational age (LGA) [OR (95% CI): 0.55 (0.28, 1.02), p = 0.059], and greater likelihood of labour induction [2.34 (1.49, 3.66), p < 0.001] than women without hyperglycaemia.

CONCLUSION

Women with GDM managed by lifestyle modification had higher induction rates and their offspring had lower birthweight z-scores, with a trend to lower LGA than those without hyperglycaemia in pregnancy. Further studies are indicated to explore reasons for higher induction rates.