Maternal Diabetes, Birth Weight, and Neonatal Risk of Congenital Heart Defects in Norway, 1994-2009

Fetal Strain and Strain Rate Measured with Speckle Tracking Echocardiography in Maternal Diabetes: Systematic Review

INTRODUCTION

The aim of this systematic review and meta-analysis was to evaluate fetal cardiac function in fetuses of mothers with diabetes compared to those of mothers without diabetes using 2D-STE.

METHODS

Embase, MEDLINE, and CENTRAL were searched for observational studies on 2D-STE fetal left and right ventricular global longitudinal strain and strain rate that included singleton, non-anomalous pregnancies complicated by pregestational or gestational diabetes mellitus compared to uncomplicated pregnancies. The strain values were pooled per 4 weeks of gestation for meta-analysis using random-effects models.

RESULTS

Fifteen studies met the criteria, including 990 fetuses of diabetic mothers and 1,645 control fetuses. The study design was cross-sectional in fourteen studies and longitudinal in one study. Gestational age, type of diabetes, ultrasound device, and 2D-STE software varied between the studies. Glycemic control and type of treatment were often lacking. In fetuses of diabetic mothers versus healthy mothers, left ventricular strain was significantly decreased (7 studies), increased (1 study), or not significantly different (7 studies). Right ventricular strain was decreased (7 studies), increased (1 study), or not different (2 studies). Left ventricular strain rate was decreased (3 studies), increased (1 study), or not different (2 studies). Right ventricular strain rate was increased (1 study) or not different (2 studies).

CONCLUSION

Fetuses of mothers with diabetes show evidence of systolic dysfunction, which is more visible in the right ventricle. Contradictory results are probably due to suboptimal study designs and variation in gestational age, diabetes severity, image acquisition, and software. Large prospective longitudinal studies are needed to assess fetal myocardial function with 2D-STE in pregestational diabetes mellitus type 1 and 2 and gestational diabetes mellitus pregnancies. The influence of glycemic control, BMI, and treatment should be evaluated.

Systematic Review and Meta-analysis of Prenatal Risk Factors for Congenital Heart Disease: Maternal Chronic Diseases and Parental Exposures

BACKGROUND

There is considerable heterogeneity in studies on prenatal risk factors for congenital heart diseases (CHDs). We performed a meta-analysis of all nongenetic factors of CHDs. This report presents results of factors related to maternal chronic diseases and parental exposures.

METHODS

A systematic search encompassing concepts of CHD and risk factors was used, using the following inclusion criteria: (1) original peer-reviewed articles, (2) quantifying the effects of risk factors for CHDs, (3) between 1989 and 2022. Pooled odds ratios (ORs) and 95% confidence interval (CI) were calculated using a random-effect model.

RESULTS

Inclusion criteria were met for 170 studies. There was an association between being overweight or obese and CHDs (OR, 1.26; 95% CI, 1.15-1.37), with a dose-effect relationship. Pregestational diabetes (PGDM) was associated with CHDs (OR, 3.51; 95% CI, 2.86-4.3), without difference between type 1 and type 2 PGDM. The effect size of gestational diabetes was less than that of PGDM (OR, 1.38; 95% CI, 1.18-1.61). There was an association between CHDs and pre-eclampsia (OR, 2.01; 95% CI, 1.32-3.05), paternal smoking (OR, 1.32; 95% CI, 1.03-1.70), and alcohol use (OR, 1.50; 95% CI, 1.08-2.08). A smaller association was found with maternal smoking and advanced maternal age.

CONCLUSIONS

There exists robust evidence for increased risk of CHD in the presence of obesity, maternal diabetes, maternal smoking, and increased maternal age. The effect sizes were relatively modest, except for PGDM. The robustness of the evidence decreased when CHDs were divided into subgroups or when the analyses were restricted to severe CHDs.

ATP5me alleviates high glucose-induced myocardial cell injury

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with adverse myocardial remodeling and impaired cardiac function of fetus. Nevertheless, specific molecular mechanisms underlying type 1 GDM-induced fetal myocardial injury remain unknown. Therefore, this study proposes to identify possible molecular mechanisms using RNA-seq.

METHODS

A rat type 1 GDM model was developed using streptozotocin (STZ) (25 and 50 mg/kg), and weight and glucose tolerance of maternal and offspring were evaluated. Changes in markers of myocardial injury and oxidative stress identified by ELISA and biochemical kits in offspring hearts. Identification of differentially expressed mRNAs (DE-mRNAs) associated with myocardial injury in type 1 GDM offspring using RNA-seq. Proliferation, apoptosis, and oxidative stress were assessed in high glucose-induced H9C2 cells after exogenously modulating ATP Synthase Membrane Subunit E (ATP5me).

RESULTS

Maternal weight, glucose and glucose tolerance, and fetal weight and heart weight were reduced in the type 1 GDM model, especially in 50 mg/kg STZ-induced. Increased of creatine kinase-MB (CK-MB), cardiac troponin T (cTnT), hypersensitive C-reactive protein (hs-CRP), reactive oxygen species (ROS) and malondialdehyde (MDA) and decreased of superoxide dismutase (SOD) were observed in type 1 GDM offspring hearts. type 1 GDM offspring hearts exhibited disorganized cardiomyocytes with enlarged gaps, broken myocardial fibers, erythrocyte accumulation and inflammatory infiltration. RNA-seq identified 462 DE-mRNAs in type 1 GDM offspring hearts, which mainly regulate immunity, redox reactions, and cellular communication. Atp5me was under-expressed in type 1 GDM offspring hearts, and high glucose decreased Atp5me expression in H9C2 cells. Overexpressing Atp5me alleviated high glucose-induced decrease in proliferation, mitochondrial membrane potential, BCL2 and SOD, and increase in apoptosis, MDA, ROS, c-Caspase-3, and BAX in H9C2 cells.

CONCLUSION

This study first demonstrated that ATP5me attenuated type 1 GDM-induced fetal myocardial injury. This provides a possible molecular mechanism for the treatment of type 1 GDM-induced fetal myocardial injury.

Understanding the Genetic and Non-genetic Interconnections in the Aetiology of Isolated Congenital Heart Disease: An Updated Review: Part 1

PURPOSE OF REVIEW

Congenital heart disease (CHD) is the most frequently occurring birth defect. Majority of the earlier reviews focussed on the association of genetic factors with CHD. A few epidemiological studies provide convincing evidence for environmental factors in the causation of CHD. Although the multifactorial theory of gene-environment interaction is the prevailing explanation, explicit understanding of the biological mechanism(s) involved, remains obscure. Nonetheless, integration of all the information into one platform would enable us to better understand the collective risk implicated in CHD development.

RECENT FINDINGS

Great strides in novel genomic technologies namely, massive parallel sequencing, whole exome sequencing, multiomics studies supported by system-biology have greatly improved our understanding of the aetiology of CHD. Molecular genetic studies reveal that cardiac specific gene variants in transcription factors or signalling molecules, or structural proteins could cause CHD. Additionally, non-hereditary contributors such as exposure to teratogens, maternal nutrition, parental age and lifestyle factors also contribute to induce CHD. Moreover, DNA methylation and non-coding RNA are also correlated with CHD. Here, we inform that a complex combination of genetic, environmental and epigenetic factors interact to interfere with morphogenetic processes of cardiac development leading to CHD. It is important, not only to identify individual genetic and non-inherited risk factors but also to recognize which factors interact mutually, causing cardiac defects.

Maternal diabetes as a teratogenic factor in fetal congenital heart disease: more than hyperglycemia

Linked article: This Correspondence comments on He et al. Click here to view the article.

Maternal Gestational Diabetes Mellitus and Congenital Heart Disease in Offspring: A Meta-Analysis

Maternal diabetes has been related to an increased risk of congenital heart disease (CHD) in offspring. However, inconsistent results were retrieved for studies evaluating the association between gestational diabetes mellitus (GDM) and CHD in offspring. We therefore performed a systematic review and meta-analysis for comprehensive investigation. Observational studies were identified by searching PubMed, Embase, and Web of Science according to the aim of the meta-analysis. A randomized-effects model was used to pool the data by incorporating the influence of potential heterogeneity. Twenty-three observational studies, involving 46953078 mother-child pairs, were available for the meta-analysis. Among them, 2131800 mothers were diagnosed as GDM and 214379 newborns had CHD. Overall, maternal GDM was associated with a higher incidence of CHD in offspring [odds ratio (OR): 1.32, 95% confidence interval (CI): 1.21 to 1.45, p<0.001; I2=62%]. Sensitivity analysis limited to studies with adjustment of maternal age and other potential confounding factors showed similar results (OR: 1.40, 95% CI: 1.30 to 1.51, p<0.001; I2=47%). Subgroup analysis suggested that the association between maternal GDM and CHD in offspring was not significantly affected by methods for diagnosis of GDM, methods for confirmation of CHD, or study quality scores (p for subgroup difference all>0.05). Subsequent analysis according to types of CHD showed that maternal GDM was associated with higher risks of atrial septal defect, ventricular septal defect, and Tetralogy of Fallot. Maternal GDM may be associated with a higher risk of CHD in offspring.

Human Genetics of d-Transposition of Great Arteries

Although several genes underlying occurrence of transposition of the great arteries have been found in the mouse, human genetics of the most frequent cyanotic congenital heart defect diagnosed in neonates is still largely unknown. Development of the outflow tract is a complex process which involves the major genes of cardiac development, acting on myocardial cells from the anterior second heart field, and on mesenchymal cells from endocardial cushions. These genes, coding for transcription factors, interact with each other, and their differential expression conditions the severity of the phenotype. A precise description of the anatomic phenotypes is mandatory to achieve a better comprehension of the complex mechanisms responsible for transposition of the great arteries.

Maternal diabetes and risk of offspring congenital heart diseases: the Japan Environment and Children's Study

BACKGROUND

Few prospective cohort studies have examined the association between maternal diabetes, including pre-pregnancy and gestational diabetes, and the risk of congenital heart disease (CHD) in Asian offspring.

METHODS

We examined the association between maternal diabetes and offspring CHD among 97,094 mother-singleton infant pairs in the Japan Environment and Children's Study (JECS) between January 2011 and March 2014. Odds ratios (OR) and 95% confidence intervals (CI) of offspring CHD based on maternal diabetes (pre-pregnancy diabetes and gestational diabetes) were estimated using logistic regression after adjusting for maternal age at delivery, pre-pregnancy body mass index (BMI), maternal smoking habits, alcohol consumption, annual household income, and maternal education. The diagnosis of CHD in the offspring was ascertained from the transcript of medical records.

RESULTS

The incidence of CHD in the offspring was 1,132. Maternal diabetes, including both pre-pregnancy diabetes and gestational diabetes, was associated with a higher risk of offspring CHD: multivariable OR (95%CI) = 1.81 (1.40-2.33) for maternal diabetes, 2.39 (1.05-5.42) for pre-pregnancy diabetes and 1.77 (1.36-2.30) for gestational diabetes. A higher risk of offspring CHD was observed in pre-pregnancy BMI ≥25.0 kg/m2 (OR = 2.55, 95% CI: 1.74-3.75) than in pre-pregnancy BMI <25.0 kg/m2 (OR = 1.49, 95% CI: 1.05-2.10, p for interaction = 0.04).

CONCLUSIONS

Maternal diabetes, including both pre-pregnancy and gestational, was associated with an increased risk of CHD in offspring.

Prevalence and treatment of gestational diabetes in Norway 2010-2020

AIMS

Estimate prevalence of gestational diabetes mellitus (GDM) and its treatment in Norway 2010-2020 and explore impact of new national GDM guidelines in 2017.

METHODS

We identified women giving birth in a nationwide cohort study using registers on births, prescriptions, education, primary and specialist care. For each year, we estimated prevalence of GDM overall, by BMI, age, education, and mother's birthplace; proportions of GDM pregnancies receiving pharmacological treatment; and distribution of the gestational week when GDM was diagnosed.

RESULTS

In 633,169 pregnancies, prevalence of GDM increased from 2.6 % in 2010 to 6.0 % in 2016, then stabilized. Similar patterns were seen across strata of BMI, age, education, and maternal birthplace, although prevalence was higher with higher BMI, higher age, lower education, and mothers born in Asia, Africa, or Middle East. The proportion of the GDM population pharmacologically treated increased from 11.6 % in 2010 to 13.6 % in 2016 and 31.6 % in 2020. GDM was diagnosed in recommended gestational week 24-28 in 19 % versus 45 % of GDM pregnancies in 2010 and 2020, respectively.

CONCLUSIONS

Both the proportion diagnosed with GDM within recommended time of screening, and who received pharmacological treatment, increased substantially following new guidelines in 2017. Prevalence of GDM increased from 2010 to 2016, then plateaued.

Associations of elevated glucose levels at each time point during OGTT with fetal congenital heart diseases: a cohort study of 72,236 births

BACKGROUND

It remains unclear how the condition of glucose metabolism during pregnancy affects fetal outcomes. This study aimed to investigate the associations of gestational diabetes mellitus (GDM) and elevated glucose levels at each time point during oral glucose tolerance test (OGTT) with congenital heart disease (CHD) risk in offspring.

METHODS

We conducted a retrospective cohort study of mothers with singleton pregnancies of 20 weeks or more registered at Maternal and Child Health Centers in Fujian Province, China. The OGTT results and offspring CHD occurrence were collected. We used logistic regression to analyse the association between elevated blood glucose at each time point during OGTT and CHD.

RESULTS

A total of 71,703 normal and 533 CHD fetuses were included. Compared to the corresponding normal group, women with GDM, elevated blood glucose at different time points in OGTT (0 h ≥ 5.1 mmol/L, 1 h ≥ 10 mmol/L, and 2 h ≥ 8.5 mmol/L) showed an increased risk of CHD in offspring (adjusted OR = 1.41, 1.36, 1.37, and 1.41, all P < 0.05, respectively). Compared to group 1 (normal OGTT 0 h, 1 h and 2 h), the risk of CHD was higher in group 3 (normal OGTT 0 h and abnormal OGTT 1 h or 2 h) and group 4 (abnormal OGTT 0 h, 1 h and 2 h), OR = 1.53 and 2.21, all P < 0.05, respectively. Moreover, we divided participants by advanced maternal age, multipara, assisted reproduction, fetal sex, and others, similar associations were observed in the subgroup analyses.

CONCLUSION

Elevated blood glucose at different time points during OGTT was associated with CHD in offspring. Fetuses of pregnant women with GDM should be screened for a high risk of CHD.

Optimally Controlled Diabetes and Its Influence on Neonatal Outcomes at a Level II Center: A Study on Infants Born to Diabetic Mothers

Background and Objectives: We investigated the effect of optimal maternal glycemic control on neonatal outcomes among infants born to mothers with diabetes. Materials and Methods: In this prospective study, we assessed 88 eligible mothers admitted to the obstetrics department for pregnancy evaluation. Our analysis included 46 infants born to diabetic mothers (IDMs) and 138 infants born to unaffected mothers, all admitted to the Level II Neonatal Intensive Care Unit (NICU). Results: Mothers affected by diabetes were generally older and exhibited a higher body mass index (BMI) and a greater number of gestations, although parity did not differ significantly. Cesarean section emerged as the most frequently chosen mode of delivery. A significantly higher proportion of infants in the affected group presented with respiratory disease (3% vs. 19.5%), which required NICU admission (4.3% vs. 23.9%), phototherapy (18.1% vs. 43.5%), and had congenital heart defects or myocardial hypertrophy (15.2% and 26% vs. 3% and 4.3%) compared to matched controls (p < 0.05). Conclusions: This study underscores the persistence of adverse neonatal outcomes in IDMs, even when maternal glycemic control is optimized. It calls for further investigation into potential interventions and strategies aimed at enhancing neonatal outcomes in this population.

Research Progress of Maternal Metabolism on Cardiac Development and Function in Offspring

The developmental origin of health and disease (DOHaD) hypothesis refers to the adverse effects of suboptimal developmental environments during embryonic and early fetal stages on the long-term health of offspring. Intrauterine metabolic perturbations can profoundly impact organogenesis in offspring, particularly affecting cardiac development and giving rise to potential structural and functional abnormalities. In this discussion, we contemplate the existing understanding regarding the impact of maternal metabolic disorders, such as obesity, diabetes, or undernutrition, on the developmental and functional aspects of the offspring's heart. This influence has the potential to contribute to the susceptibility of offspring to cardiovascular health issues. Alteration in the nutritional milieu can influence mitochondrial function in the developing hearts of offspring, while also serving as signaling molecules that directly modulate gene expression. Moreover, metabolic disorders can exert influence on cardiac development-related genes epigenetically through DNA methylation, levels of histone modifications, microRNA expression, and other factors. However, the comprehensive understanding of the mechanistic underpinnings of these phenomena remains incomplete. Further investigations in this domain hold profound clinical significance, as they can contribute to the enhancement of public health and the prevention of cardiovascular diseases.

Pre-gestational diabetes and the risk of congenital heart defects in the offspring: A French nationwide study

AIM

To compare the frequencies and types of congenital heart defects for infants of women without and with pre-gestational diabetes, type 1 and type 2 diabetes (T1DM, T2DM) and to identify risk factors.

METHODS

All live births between 2012 and 2020 were screened for maternal diabetes and infant congenital heart defects using the French Medical Information System Program in Medicine, Surgery and Obstetrics database (PMSI-MCO). Incidences of these defects were estimated, and a logistic model evaluated maternal and fetal prognostic risk factors.

RESULTS

Overall, 6,038,703 mothers did not have pre-gestational diabetes (no-diabetes), 23,147 had T1DM, and 14,401 had T2DM. The incidence of infant congenital disease was 6.2% for the no-diabetes group, 8.0%, for women with T1DM, and 8.4% for women with T2DM (P < 0.001); for congenital heart defects, incidences were respectively 0.8%, 3.0% and 2.7% (P < 0.001). In comparison with the no-diabetes group, the odds ratios (95%CI) of coronary heart defects were 2.07 (1.91;2.24) (P < 0.001) for women with T1DM and 2.20 (1.99;2.44) (P < 0.001) for women with T2DM, with no difference between T1DM and T2DM (P = 0.336). cesarian section, small and large for gestational age, and prematurity were also associated with an increased risk of congenital heart defects.

CONCLUSION

In this study we observed higher incidences of congenital heart defects in infants of women with pre-gestational diabetes compared to women without pre-gestational diabetes, with no difference between women with T1DM or T2DM. These data call for intensifying preconception care and justify systematic cardiac echography in selected fetuses.

Pregestational Diabetes and Congenital Heart Defects

Studies have consistently shown a significant increase in the risk of congenital heart defects in the offspring of diabetic mothers compared with those of nondiabetic pregnancies. Evidence points that all types of pregestational diabetes have the capacity of generating cardiac malformations in a more accentuated manner than in gestational diabetes, and there seems to be an increased risk for all congenital heart defects phenotypes in the presence of maternal diabetes. Currently, the application of some therapies is under study in an attempt to reduce the risks inherent to diabetic pregnancies; however, it has not yet been possible to fully prove their effectiveness. The present review aims to better understand the mechanisms that govern the association between pregestational diabetes and congenital heart defects and how maternal diabetes interferes with fetal cardiac development, as there is still a long way to go in the investigation of this complex process.

Epigenetics and Congenital Heart Diseases

Congenital heart disease (CHD) is a frequent occurrence, with a prevalence rate of almost 1% in the general population. However, the pathophysiology of the anomalous heart development is still unclear in most patients screened. A definitive genetic origin, be it single-point mutation or larger chromosomal disruptions, only explains about 35% of identified cases. The precisely choreographed embryology of the heart relies on timed activation of developmental molecular cascades, spatially and temporally regulated through epigenetic regulation: chromatin conformation, DNA priming through methylation patterns, and spatial accessibility to transcription factors. This multi-level regulatory network is eminently susceptible to outside disruption, resulting in faulty cardiac development. Similarly, the heart is unique in its dynamic development: growth is intrinsically related to mechanical stimulation, and disruption of the intrauterine environment will have a direct impact on fetal embryology. These two converging axes offer new areas of research to characterize the cardiac epigenetic regulation and identify points of fragility in order to counteract its teratogenic consequences.

Risks of specific congenital anomalies in offspring of women with diabetes: A systematic review and meta-analysis of population-based studies including over 80 million births

BACKGROUND

Pre-gestational diabetes mellitus (PGDM) has been known to be a risk factor for congenital heart defects (CHDs) for decades. However, the associations between maternal PGDM and gestational diabetes mellitus (GDM) and the risk of specific types of CHDs and congenital anomalies (CAs) in other systems remain under debate. We aimed to investigate type-specific CAs in offspring of women with diabetes and to examine the extent to which types of maternal diabetes are associated with increased risk of CAs in offspring.

METHODS AND FINDINGS

We searched PubMed and Embase from database inception to 15 October 2021 for population-based studies reporting on type-specific CAs in offspring born to women with PGDM (combined type 1 and 2) or GDM, with no limitation on language. Reviewers extracted data for relevant outcomes and performed random effects meta-analyses, subgroup analyses, and multivariable meta-regression. Risk of bias appraisal was performed using the Cochrane Risk of Bias Tool. This study was registered in PROSPERO (CRD42021229217). Primary outcomes were overall CAs and CHDs. Secondary outcomes were type-specific CAs. Overall, 59 population-based studies published from 1990 to 2021 with 80,437,056 participants met the inclusion criteria. Of the participants, 2,407,862 (3.0%) women had PGDM and 2,353,205 (2.9%) women had GDM. The meta-analyses showed increased risks of overall CAs/CHDs in offspring born to women with PGDM (for overall CAs, relative risk [RR] = 1.99, 95% CI 1.82 to 2.17, P < 0.001; for CHDs, RR = 3.46, 95% CI 2.77 to 4.32, P < 0.001) or GDM (for overall CAs, RR = 1.18, 95% CI 1.13 to 1.23, P < 0.001; for CHDs, RR = 1.50, 95% CI 1.38 to 1.64, P < 0.001). The results of the meta-regression analyses showed significant differences in RRs of CAs/CHDs in PGDM versus GDM (all P < 0.001). Of the 23 CA categories, excluding CHD-related categories, in offspring, maternal PGDM was associated with a significantly increased risk of CAs in 21 categories; the corresponding RRs ranged from 1.57 (for hypospadias, 95% CI 1.22 to 2.02) to 18.18 (for holoprosencephaly, 95% CI 4.03 to 82.06). Maternal GDM was associated with a small but significant increase in the risk of CAs in 9 categories; the corresponding RRs ranged from 1.14 (for limb reduction, 95% CI 1.06 to 1.23) to 5.70 (for heterotaxia, 95% CI 1.09 to 29.92). The main limitation of our analysis is that some high significant heterogeneity still persisted in both subgroup and sensitivity analyses.

CONCLUSIONS

In this study, we observed an increased rate of CAs in offspring of women with diabetes and noted the differences for PGDM versus GDM. The RRs of overall CAs and CHDs in offspring of women with PGDM were higher than those in offspring of women with GDM. Screening for diabetes in pregnant women may enable better glycemic control, and may enable identification of offspring at risk for CAs.

Gestational Diabetes Mellitus in Europe: A Systematic Review and Meta-Analysis of Prevalence Studies

Background

Gestational Diabetes Mellitus (GDM) is defined as the type of hyperglycemia diagnosed for the first-time during pregnancy, presenting with intermediate glucose levels between normal levels for pregnancy and glucose levels diagnostic of diabetes in the non-pregnant state. We aimed to systematically review and meta-analyze studies of prevalence of GDM in European countries at regional and sub-regional levels, according to age, trimester, body weight, and GDM diagnostic criteria.

Methods

Systematic search was conducted in five databases to retrieve studies from 2014 to 2019 reporting the prevalence of GDM in Europe. Two authors have independently screened titles and abstracts and full text according to eligibility using Covidence software. A random-effects model was used to quantify weighted GDM prevalence estimates. The National Heart, Lung, and Blood Institute criteria was used to assess the risk of bias.

Results

From the searched databases, 133 research reports were deemed eligible and included in the meta-analysis. The research reports yielded 254 GDM-prevalence studies that tested 15,572,847 pregnant women between 2014 and 2019. The 133 research reports were from 24 countries in Northern Europe (44.4%), Southern Europe (27.1%), Western Europe (24.1%), and Eastern Europe (4.5%). The overall weighted GDM prevalence in the 24 European countries was estimated at 10.9% (95% CI: 10.0-11.8, I2 : 100%). The weighted GDM prevalence was highest in the Eastern Europe (31.5%, 95% CI: 19.8-44.6, I2 : 98.9%), followed by in Southern Europe (12.3%, 95% CI: 10.9-13.9, I2 : 99.6%), Western Europe (10.7%, 95% CI: 9.5-12.0, I2 : 99.9%), and Northern Europe (8.9%, 95% CI: 7.9-10.0, I2 : 100). GDM prevalence was 2.14-fold increased in pregnant women with maternal age ≥30 years (versus 15-29 years old), 1.47-fold if the diagnosis was made in the third trimester (versus second trimester), and 6.79- fold in obese and 2.29-fold in overweight women (versus normal weight).

Conclusions

In Europe, GDM is significant in pregnant women, around 11%, with the highest prevalence in pregnant women of Eastern European countries (31.5%). Findings have implications to guide vigilant public health awareness campaigns about the risk factors associated with developing GDM.

Systematic Review Registration

PROSPERO [https://www.crd.york.ac.uk/PROSPERO/], identifier CRD42020161857.

Congenital Malformation Risk According to Hemoglobin A1c Values in a Contemporary Cohort with Pregestational Diabetes

OBJECTIVE

The study aimed to evaluate the association between hemoglobin A1c values and likelihood of fetal anomalies in women with pregestational diabetes.

STUDY DESIGN

Women with pregestational diabetes who delivered at a single institution that serves a nonreferred population from May 1, 2009 to December 31, 2018 were ascertained. Hemoglobin A1c values were obtained at the first prenatal visit. Women who delivered a singleton live- or stillborn infant with a major malformation as defined by European Surveillance of Congenital Anomalies criteria were identified. In infants with multiple system anomalies, each malformation was considered separately. Hemoglobin A1c values were analyzed categorically by using Mantel-Haenszel method and continuously with linear regression for trend for fetal anomalies.

RESULTS

A total of 1,676 deliveries to women with pregestational diabetes were delivered at our institution, and hemoglobin A1c was assessed in 1,573 deliveries (94%). There were 129 deliveries of an infant with at least one major malformation, an overall anomaly rate of approximately 8%. Mean hemoglobin A1c concentration was significantly higher in pregnancies with anomalous infants, 9.3 ± 2.1% versus 8.0 ± 2.1%, and p <0.001. There was no difference in gestational age at the time hemoglobin A1c was obtained, 13 ± 8.3 versus 14 ± 8.7 weeks. Hemoglobin A1c was associated with increased probability of a congenital malformation. This reached 10% with a hemoglobin A1c concentration of 10%, and 20% with a hemoglobin A1c of 13%. Similar trends were seen when examining risk of anomalies by organ system with increasing hemoglobin A1c levels, with the greatest increase in probability for both cardiac and genitourinary anomalies.

CONCLUSION

In women with pregestational diabetes, hemoglobin A1c is strongly associated with fetal anomaly risk. Data from a contemporary cohort may facilitate counseling and also highlight the need for preconceptual care and glycemic optimization prior to entry to obstetric care.

KEY POINTS

· Infants of diabetic mothers had an 8% major anomaly rate.. · HbA1c of 10% in pregnancy associated with 10% anomaly rate.. · HbA1c of 13% in pregnancy associated with 20% anomaly rate.. · Preconceptual care is important to reduce prevalence..

Population-based study on birth outcomes among women with hypertensive disorders of pregnancy and gestational diabetes mellitus

To evaluate birth outcomes in women with hypertensive disorders of pregnancy (HDP) and gestational diabetes mellitus (GDM), we used insurance data of Taiwan to evaluate 11 adverse neonatal outcomes of infants born to women with HDP (N = 7775) and with both HDP and GDM (HDP/GDM) (N = 1946), comparing to women with neither disorder (N = 19,442), matched by age. The impacts of preeclampsia/eclampsia were also evaluated. Results showed that Caesarean section delivery was near 1.7-fold greater in the HDP/GDM and HDP groups than in comparisons. The preterm delivery rates were more than threefold greater in HDP/GDM group and HDP group than in comparisons with adjusted odds ratios (aORs) of 4.84 (95% confidence interval (CI) 4.34–5.40) and 3.92 (95% CI 3.65–4.21), respectively, followed by jaundice (aORs 2.95 (95% CI 2.63–3.33) and 1.90 (95% CI 1.76–2.06)), and small gestation age (SGA) (aORs 6.57 (95% CI 5.56–7.75) and 5.81 (95% CI 5.15–6.55)). Incidence rates of birth trauma, patent ductus arteriosus, atrial septal defect, respiratory distress syndrome, and neonatal hypoglycemia were also higher in the HDP/GDM and HDP groups than in the comparison group. Most adverse outcomes increased further in women with preeclampsia or eclampsia. In conclusion, women with HDP are at elevated risks of adverse neonatal outcomes. Risks of most adverse outcomes increase further for women with both HDP and GDM. Preeclampsia or eclampsia may also contribute to these outcomes to higher risk levels. Every pregnant woman with these conditions deserves specialized prenatal care.

"Maternal diabetes mellitus and its impact on the risk of delivering a child with congenital heart disease: a systematic review and meta-analysis"

AIM

Maternal pregestational diabetes mellitus (PGDM), type 1 or type 2, has been established as a potential risk factor for congenital heart disease (CHD). At the same time, the correlation between gestational diabetes mellitus (GDM) and increased risk of CHD has not been yet fully elucidated. The objective of this systematic review and meta-analysis (PROSPERO number: CRD42020182390) was to analyze the existing evidence on PGDM and to attempt to fill, to the best of our ability, the remaining knowledge gap in the association of GDM with CHD.

MATERIALS AND METHODS

Two authors have independently searched the Pubmed/Medline, Scopus, Cochrane, Web of Science, and Theses Global databases with keywords and Boolean operators. The search yielded 9333 relevant articles, which were later screened for eligibility. Original peer-reviewed (case-control or cohort) studies were included if they were published in English between 1997 and 2020. Thirteen studies on mothers with PGDM and seven studies on mothers with GDM were finally included in our meta-analysis to investigate the association of maternal diabetes with the risk of delivering a child with CHD. The selected studies were all assessed for their methodological quality using the Newcastle-Ottawa scale. Associations with p < .05 were considered statistically significant.

RESULTS

Our meta-analysis (I² > 75%, total population: n = 12,461,586) of 79,476 women with PGDM and 160,893 with GDM produced an odds ratio of 3.48 (2.36-4.61) and 1.55 (1.48-1.61), respectively. Additionally, we did not find any noticeable difference in the risk for CHD among diabetic women living in the USA and Europe. Nevertheless, it still needs to be clarified, whether or not the gestational diabetic population includes undiagnosed women with preexisting diabetes, which might account for the increased risk of delivering a child with CHD in women classified as suffering from GDM.

CONCLUSION

While both GDM and PGDM seem to significantly increase the risk of CHD in comparison with the general population, PDGM appears to have a greater association with CHD, being correlated with a 3.5-fold increase in the risk of malformation. Preconceptional and gestational diabetes care are, therefore, essential to mitigate the adverse effect of hyperglycemia on fetal heart formation during pregnancy.

Maternal obesity and metabolic disorders associate with congenital heart defects in the offspring: A systematic review

BACKGROUND

Congenital heart defects (CHDs) are the most common congenital malformations. The aetiology of CHDs is complex. Large cohort studies and systematic reviews and meta-analyses based on these have reported an association between higher risk of CHDs in the offspring and individual maternal metabolic disorders such as obesity, diabetes, hypertension, and preeclampsia, all conditions that can be related to insulin resistance or hyperglycaemia. However, the clinical reality is that these conditions often occur simultaneously. The aim of this review is, in consequence, both to evaluate the existing evidence on the association between maternal metabolic disorders, defined as obesity, diabetes, hypertension, preeclampsia, dyslipidaemia and CHDs in the offspring, as well as the significance of combinations, such as metabolic syndrome, as risk factors.

METHODS

A systematic literature search of papers published between January 1, 1990 and January 14, 2021 was conducted using PubMed and Embase. Studies were eligible if they were published in English and were case-control or cohort studies. The exposures of interest were maternal overweight or obesity, hypertension, preeclampsia, diabetes, dyslipidaemia, and/or metabolic syndrome, and the outcome of interest was CHDs in the offspring. Furthermore, the studies were included according to a quality assessment score.

RESULTS

Of the 2,250 identified studies, 32 qualified for inclusion. All but one study investigated only the individual metabolic disorders. Some disorders (obesity, gestational diabetes, and hypertension) increased risk of CHDs marginally whereas pre-gestational diabetes and early-onset preeclampsia were strongly associated with CHDs, without consistent differences between CHD subtypes. A single study suggested a possible additive effect of maternal obesity and gestational diabetes.

CONCLUSIONS

Future studies of the role of aberrations of the glucose-insulin homeostasis in the common aetiology and mechanisms of metabolic disorders, present during pregnancy, and their association, both as single conditions and-particularly-in combination, with CHDs are needed.

Periconception glycemic control and congenital anomalies in women with pregestational diabetes

INTRODUCTION

To assess the relationship between periconception glycemic control and congenital anomalies in a contemporary, diverse population of women with pregestational diabetes.

RESEARCH DESIGN AND METHODS

This is a retrospective cohort study of all pregnant women with pregestational diabetes at a single institution (2003-2017) in the USA. The primary outcome was frequency of major or minor congenital anomalies. Glycemic control was assessed by periconception glycosylated hemoglobin (HbA1c). The association of periconception HbA1c with pregnancy outcomes was assessed using bivariable and multivariable analyses.

RESULTS

Our sample included 351 women, of which 63.8% had type 2 diabetes. Our study cohort is racially and ethnically diverse, with approximately equal numbers of women identifying as white non-Hispanic, black non-Hispanic and Hispanic, with 3.4% identifying as Asian. Of these 351 women, 52 (14.8%) had a fetus with a congenital anomaly, of whom the majority (n=43) had a major anomaly. Over half (51.1%) of all major anomalies were cardiovascular. Compared with the group with the best glycemic control (HbA1c ≤7.4%), which had an anomaly frequency of 10.2%, the frequency of congenital anomalies increased significantly with each category of worsening glycemic control (HbA1c 7.5%-9.4%: 20.6%, adjusted OR (aOR) 2.35, 95% confidence interval (CI) 1.08 to 5.13; HbA1c 9.5% to 11.4%: 25.8%, aOR 2.86, 95% CI 1.08 to 7.59; HbA1c ≥11.5%: 37.5%, aOR 7.66, 95% CI 2.27 to 25.9).

CONCLUSION

In a diverse cohort of women with pregestational diabetes, higher periconception HbA1c, especially HbA1c >9.5, was significantly associated with major congenital fetal anomalies. Our study sample is reflective of the current population of pregnant women with diabetes, including women with type 2 diabetes and from racial and ethnic minorities.

Could Subtle Obstetrical Brachial Plexus Palsy Be Related to Unilateral B Glenoid Osteoarthritis?

Background: Several factors associated with B glenoid are also linked with obstetrical brachial plexus palsy (OBPP). The purpose of this observational study was to determine the incidence of OBPP risk factors in type B patients. Methods: A cohort of 154 patients (68% men, 187 shoulders) aged 63 ± 17 years with type B glenoids completed a questionnaire comprising history of perinatal characteristics related to OBPP. A literature review was performed following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) to estimate the incidence of OBPP risk factors in the general population. Results: Twenty-seven patients (18%) reported one or more perinatal OBPP risk factors, including shoulder dystocia (n = 4, 2.6%), macrosomia >4 kg (n = 5, 3.2%), breech delivery (n = 6, 3.9%), fetal distress (n = 8, 5.2%), maternal diabetes (n = 2, 1.3%), clavicular fracture (n = 2, 1.3%), and forceps delivery (n = 4, 2.6%). The comparison with the recent literature suggested that most perinatal OBPP risk factors were within the normal range, although the incidence of shoulder dystocia, forceps and vaginal breech deliveries exceeded the average rates. Conclusion: Perinatal factors related to OBPP did not occur in a higher frequency in patients with Walch type B OA compared to the general population, although some of them were in the high normal range.

Ultrasound for the Pregnant Person With Diabesity

Diabetes and obesity increase the risk of congenital anomalies, but the putative mechanisms of this increased risk are not fully elucidated. In this chapter, we delve into sonographic characteristics associated with diabetes and obesity, including fetal structural anomalies, functional cardiac alterations, and growth abnormalities. We will also discuss the technical challenges of imaging in the patient with diabesity and propose methodologies for optimizing imaging. Lastly, we will address the prevention of workplace-associated musculoskeletal disorders injury for sonographers.

A Systematic Review of the Prevalence of Gestational Diabetes in Norway

Gestational diabetes mellitus (GDM) is a major public health problem and a threat to maternal and child health. There is a lack of integrated and systematically synthesized knowledge about the prevalence GDM in Norway. Therefore, this systemic review aimed to present the best available peer-reviewed published evidence from the past 20 years about the prevalence of GDM in Norway. A comprehensive literature search was performed on online databases consisting of PubMed (including Medline), Web of Science, and Scopus to retrieve original research articles published on the prevalence of GDM up to August 2020. Also, databases of Norart and SveMed⁺ in the Norwegian language were searched to enhance the search coverage. Data were extracted using a standardized protocol and data collection form and were presented narratively. A total of 11 studies were selected to include for data analysis and synthesis with the total sample size of 2,314,191 pregnant women. The studies included heterogenous populations and mostly reported the prevalence of GDM in healthy mothers with singleton pregnancies. The prevalence of GDM in population registered-based studies in Norway was reported to be lower than 2%, using the World Health Organization (WHO) 1999 criteria. However, studies on high-risk populations such as the non-European ethnicity reported prevalence rates ranging from 8% to 15%. Given the evidence from available literature that reported trends in the prevalence of GDM, an increase in the prevalence of GDM across most racial/ethnic groups studied in Norway was observed. Overall, the prevalence of GDM in the low risk population of Norway is fairly low, but the available literature supports the perspective that the prevalence of GDM has shown an increasing trend in recent decades. This finding is very important for health service planning and evaluation, policy development, and research in Norway. Large-scale prospective studies, using the national data, are warranted to provide firm evidence over coming years. Our review findings can help policy makers devise appropriate strategies for improving women's reproductive health.

A Pragmatic Approach to the Treatment of Women With Type 2 Diabetes in Pregnancy

Type 2 diabetes mellitus (DM) is a growing problem among reproductive-aged women. Contemporary trends in obesity and delayed child-bearing are expected to result in an increasing number of pregnancies affected by type 2 DM. Women with known type 2 DM can greatly benefit from preconception care as improved periconception glycemic control and weight loss can decrease the neonatal and maternal risks associated with type 2 DM and pregnancy. Antenatal mainstays of management include frequent blood glucose monitoring, insulin therapy, optimization of coexisting medical conditions, and fetal surveillance. Careful attention to postpartum glucose control, infant feeding choices, and contraceptive counseling are important aspects of immediate postpartum care.

Fetal Anomaly Detection in Pregnancies With Pregestational Diabetes

OBJECTIVES

To evaluate fetal anomaly detection in pregnancies with pregestational diabetes, according to the gestational age at the time of specialized sonography, use of follow-up sonography, maternal body mass index, and organ system(s) involved.

METHODS

Women with pregestational diabetes who received prenatal care and delivered a live-born or stillborn neonate at our hospital from October 2011 through April 2017 were ascertained. We included all pregnancies with at least 1 confirmed structural anomaly (EUROCAT classification) who had detailed sonography at 18 weeks' gestation or later. We analyzed detection of anomalous fetuses at the initial detailed sonogram and, if no abnormality was identified, during any follow-up sonograms. Statistical analyses were performed with the χ² test and Mantel-Haenszel χ² test for trend.

RESULTS

Seventy-two anomalous neonates (72 of 1060 [6.8%]) were born. Overall detection was 55 of 72 (76%); 49 of 72 (68%) were detected at the initial detailed sonogram, compared to 6 of 15 (40%) of follow-up examinations (P = .04). Recognition at the initial or follow-up examination was not dependent on gestational age or body mass index category (all P > .05). Of individual organ system anomalies, 67 of 89 (75%) were identified. Detection exceeded 85% for central nervous system, genitourinary, and musculoskeletal abnormalities and 43% for craniofacial anomalies. Sixty-five percent of cardiac anomalies were detected, and 14 of 17 (82%) requiring specialized care in the immediate neonatal period were recognized.

CONCLUSIONS

Approximately three-fourths of anomalous fetuses were identified, with greater detection at the initial detailed examination. Fetuses with central nervous system, genitourinary, musculoskeletal abnormalities and those with cardiac anomalies requiring specialized cardiac care were more likely to come to attention.

Comprehensive assessment of the associations between maternal diabetes and structural birth defects in offspring: a phenome-wide association study

PURPOSE

Our objective was to comprehensively evaluate the risk of a broad range of birth defects among offspring of women with diabetes, overall and stratified by pregestational versus gestational diagnosis, using the phenome-wide association (PheWAS) methodology.

METHODS

We performed a registry linkage study of all live births (>6,500,000) and birth defects cases (>290,000) in Texas, 1999-2015. We ascertained diabetes from birth and fetal death certificates. We calculated prevalence rate ratios (PRR) for phenotypes with ≥10 cases among exposed offspring (n = 130).

RESULTS

Diabetes was associated with the prevalence of any defect (PRR 1.40, 95% confidence interval [CI] 1.38-1.42), multiple defects (PRR 1.86, 95% CI 1.81-1.91), and 60 specific phenotypes, including novel (hypospadias, mitral stenosis) and previously reported phenotypes (renal a-/dysgenesis, spinal anomalies). Pregestational diabetes was a stronger risk factor for any defect (PRR 2.00, 95% CI 1.93-2.07), multiple defects (PRR 3.27, 95% CI 3.11-3.44), and the 60 specific phenotypes evaluated. Gestational diabetes was associated with any defect (PRR 1.21, 95% CI 1.19-1.23) and 47 specific birth defects phenotypes, although associations were weaker than for pregestational diabetes.

CONCLUSIONS

The PheWAS is an efficient way to identify risk factors for disease using population-based registry data. Pregestational diabetes is associated with a broader range of phenotypes than previously reported. Because diabetes is diagnosed in 1% of women prior to pregnancy and 6%-9% during pregnancy, our results highlight a significant public health concern.

Maternal Obesity and Diabetes Mellitus as Risk Factors for Congenital Heart Disease in the Offspring

Congenital heart disease (CHD) is the most common anatomical malformation occurring live‐born infants and an increasing cause of morbidity and mortality across the lifespan and throughout the world. Population‐based observations have long described associations between maternal cardiometabolic disorders and the risk of CHD in the offspring. Here we review the epidemiological evidence and clinical observations relating maternal obesity and diabetes mellitus to the risk of CHD offspring with particular attention to mechanistic models of maternal‐fetal risk transmission and first trimester disturbances of fetal cardiac development. A deeper understanding of maternal risk factors holds the potential to improve both prenatal detection of CHD by identifying at‐risk pregnancies, along with primary prevention of disease by improving preconception and prenatal treatment of at‐risk mothers.

Management of pregestational diabetes mellitus: a comparison of guidelines

Background: Pregestational diabetes is associated with adverse maternal and neonatal outcomes. The aim of this study was to summarize and compare evidence-based recommendations on pregestational diabetes and to focus especially on issues related to the management of this entity.Materials and methods: A descriptive review of three recently published national guidelines on pregestational diabetes was conducted: the American Diabetes Association on "Diabetes in Pregnancy: Standards of Medical Care in Diabetes - 2019," the National Institute for Health and Care Excellence on "Diabetes in pregnancy: management from preconception to the postnatal period" and the American College of Obstetricians and Gynecologists on "Pregestational Diabetes Mellitus." These guidelines were compared according to recommendations on management, during the preconception, antenatal, intrapartum and postpartum period.Results: There were many similar recommendations regarding the preconception counseling, the antepartum assessment by specialists, the glycemic control target levels, the pharmacologic treatment and the postpartum period among the three guidelines. On the other hand, the American Diabetes Association makes no recommendations regarding fetal monitoring and obstetric management during pregnancy and the intrapartum period, while there are several similarities between the other two guidelines.Conclusions: The adoption of an international consensus based on evidence - based guidelines will increase the awareness of the healthcare professionals on the management of pregestational diabetes, leading that way to more favorable perinatal outcomes.

Folate supplementation for prevention of congenital heart defects and low birth weight: an update

Women planning a pregnancy and pregnant women in the first trimester are recommended to use folate-containing supplements in order to prevent neural tube defects. The prevention of many cases of neural tube defects with folic acid is evident from meta-analysis, randomized controlled trials (RCTs), observational studies in humans and experimental evidence in animals. However, folate supplementation in pregnant women or a higher maternal folate status has been shown to be protective against other adverse birth outcomes such as congenital heart defects, low birth weight, and preterm birth. Additionally, infants and children with congenital heart defects often show disorders in folate metabolism (low folate, higher homocysteine, or low vitamin B12). Maternal genotype for several folate metabolizing genes has shown associations with the risk of having a child with congenital heart defect. There is some evidence that folate supplementation could have differential effects on sub-types of congenital heart defects, but it is not clear whether the prevention time window is the same as for neural tube defects. Some studies proposed a high dose of folic acid (in mg/d) to prevent congenital heart defects in women with a high global risk (such as those with diabetes or obesity). There are currently no RCTs to support that doses of folic acid in mg range are more effective than the currently recommended 400-800 µg/d taken at least 2-3 months before conception until the end of the first trimester.

Intergenerational Effects of Health Issues Among Women of Childbearing Age: a Review of the Recent Literature

PURPOSE OF REVIEW

This review summarizes the latest scientific evidence, primarily from systematic reviews/meta-analyses and large cohort studies, on the impact of health issues among women of childbearing age and their effect on their offspring during pregnancy and from birth to adulthood.

RECENT FINDINGS

Women of childbearing age with overweight/obesity, diabetes, and hypertension prior to pregnancy are at increased risk for adverse outcomes during pregnancy, such as excessive gestational weight gain, gestational diabetes mellitus, and hypertensive disorders of pregnancy. These adverse outcomes could complicate delivery and put their offspring at risk of developing overweight/obesity, diabetes, and hypertension (i.e., intergenerational transmission of health issues). Interventions should target women of childbearing age, especially those who wish to conceive, in order to possibly stop the transmission of women's health issues to the offspring and favor a healthy pregnancy from the start. This could be one of the best strategies to promote both maternal and child health.

The association of elevated maternal genetic risk scores for hypertension, type 2 diabetes and obesity and having a child with a congenital heart defect

Background

Maternal hypertension, type 2 diabetes (T2D) and obesity are associated with an increased risk of having offspring with conotruncal heart defects (CTDs). Prior studies have identified sets of single nucleotide polymorphisms (SNPs) that are associated with risk for each of these three adult phenotypes. We hypothesized that these same SNPs are associated with maternal risk of CTDs in offspring.

Methods and results

We evaluated the parents of children with a CTD ascertained from the Children’s Hospital of Philadelphia (n = 466) and by the Pediatric Cardiac Genomic Consortium (n = 255). We used a family-based design to assess the association between CTDs and the maternal genotype for individual hypertension, T2D, and obesity-related SNPs and found no association between CTDs and the maternal genotype for any individual SNP. In addition, we calculated genetic risk scores (GRS) for hypertension, T2D, and obesity using previously published GRS formulas. When comparing the GRS of mothers to fathers, there were no statistically significant differences in the mean for the combined GRS or the GRS for each individual condition. However, when we categorized the mothers and fathers of cases with CTDs as having high (>95^th percentile) or low (≤95^th percentile) scores, compared to fathers, mothers had almost two times the odds of having a high GRS for hypertension (OR 1.7, 95% CI 1.0, 2.8) and T2D (OR 1.8, 95% CI 1.1, 3.1).

Conclusions

Our results support a link between maternal genetic risk for hypertension/T2D and CTDs in their offspring. These associations might be independent of maternal phenotype at conception.

Periconception glycaemic control in women with type 1 diabetes and risk of major birth defects: population based cohort study in Sweden

OBJECTIVE

To examine the association between maternal type 1 diabetes and the risk of major birth defects according to levels of glycated haemoglobin (HbA1C) within three months before or after estimated conception.

DESIGN

Population based historical cohort study using nationwide health registers.

SETTING

Sweden, 2003-15.

PARTICIPANTS

2458 singleton liveborn infants of mothers with type 1 diabetes and a glycated haemoglobin measurement within three months before or after estimated conception and 1 159 865 infants of mothers without diabetes.

MAIN OUTCOME MEASURES

Major cardiac and non-cardiac birth defects according to glycated haemoglobin levels.

RESULTS

122 cases of major cardiac defects were observed among 2458 infants of mothers with type 1 diabetes. Compared with 15 cases of major cardiac defects per 1000 infants of mothers without diabetes, the rates among infants of mothers with type 1 diabetes were 33 per 1000 for a glycated haemoglobin level of <6.5% (adjusted risk ratio 2.17, 95% confidence interval 1.37 to 3.42), 49 per 1000 for 6.5% to <7.8% (3.17, 2.45 to 4.11), 44 per 1000 for 7.8% to <9.1% (2.79, 1.90 to 4.12), and 101 per 1000 for ≥9.1% (6.23, 4.32 to 9.00). The corresponding adjusted risk differences were 17 (5 to 36), 32 (21 to 46), 26 (13 to 46), and 77 (49 to 118) cases of major cardiac defects per 1000 infants, respectively. 50 cases of major non-cardiac defects were observed among infants of mothers with type 1 diabetes. Compared with 18 cases of major non-cardiac defects per 1000 infants of mothers without diabetes, the rates among infants of mothers with type 1 diabetes were 22 per 1000 for a glycated haemoglobin level of <6.5% (adjusted risk ratio 1.18, 0.68 to 2.07), 19 per 1000 for 6.5% to <7.8% (1.01, 0.66 to 1.54), 17 per 1000 for 7.8% to <9.1% (0.89, 0.46 to 1.69), and 32 per 1000 for ≥9.1% (1.68, 0.85 to 3.33).

CONCLUSION

Among liveborn infants of mothers with type 1 diabetes, increasingly worse glycaemic control in the three months before or after estimated conception was associated with a progressively increased risk of major cardiac defects. Even with glycated haemoglobin within target levels recommended by guidelines (<6.5%), the risk of major cardiac defects was increased more than twofold. The risk of major non-cardiac defects was not statistically significantly increased at any of the four glycated haemoglobin levels examined; the study had limited statistical power for this outcome and was based on live births only.

Recent Advances in Placenta-Heart Interactions

Congenital heart defects (CHD) occur in ∼1 in every 100 live births. In addition, an estimated 10% of fetal loss is due to severe forms of CHD. This makes heart defects the most frequently occurring birth defect and single cause of in utero fatality in humans. There is considerable evidence that CHD is heritable, indicating a strong contribution from genetic risk factors. There are also known external environmental exposures that are significantly associated with risk for CHD. Hence, the majority of CHD cases have long been considered to be multifactorial, or generally caused by the confluence of several risk factors potentially from genetic, epigenetic, and environmental sources. Consequently, a specific cause can be very difficult to ascertain, although patterns of associations are very important to prevention. While highly protective of the fetus, the in utero environment is not immune to insult. As the conduit between the mother and fetus, the placenta plays an essential role in maintaining fetal health. Since it is not a fully-formed organ at the onset of pregnancy, the development of the placenta must keep pace with the growth of the fetus in order to fulfill its critical role during pregnancy. In fact, the placenta and the fetal heart actually develop in parallel, a phenomenon known as the placenta–heart axis. This leaves the developing heart particularly vulnerable to early placental insufficiency. Both organs share several developmental pathways, so they also share a common vulnerability to genetic defects. In this article we explore the coordinated development of the placenta and fetal heart and the implications for placental involvement in the etiology and pathogenesis of CHD.

Cardiac function in newborns of obese women and the effect of exercise during pregnancy. A randomized controlled trial

Background

The prevalence of maternal obesity is rising. Pre-pregnancy obesity is associated with later cardiovascular disease in the child and the underlying pathogenesis begins in early life. Therefore, pregnancy and infancy are key periods for potential intervention. The aim of this study was to study the cardiac function in newborns of obese women compared to newborns of normal-weight women, and to determine if exercise intervention during pregnancy could have an effect on cardiac function of newborns to obese women.

Material and methods

Fifty-five pregnant women, 51 obese (BMI ≥ 30 kg/m²) and four overweight (BMI 28–30 kg/m²), were randomized to an exercise training group (n = 27) or a control group (standard maternity care, n = 28). From gestational week 14 until delivery participants in the intervention group were offered supervised training sessions three times weekly. In addition, they were told to exercise at home once weekly. All newborns had an echocardiogram performed 1–3 days and 6–8 weeks after delivery. The results were compared with newborns of normal weight women (n = 20, standard maternity care).

Results

Newborns of obese women had an impaired systolic and diastolic cardiac function with reduced global strain, strain rate, tissue Doppler velocities and a thicker intraventricular septum at birth and after 6–8 weeks after delivery compared to newborns of normal weight women. Exercise had no statistically significant effect on either of the cardiac function parameters. The mean (± standard deviation) adherence to the exercise protocol was 1.3 ± 0.8 sessions per week for supervised training and 0.8 ± 0.7 sessions per week for home-based exercise training.

Conclusions

Newborns of obese women had reduced cardiac function and thicker intraventricular septum compared to newborns of normal weight women. Exercise training during pregnancy had no significant effect, potentially due to a low number of subjects and low adherence to the exercise protocol.

Trial registration

ClinicalTrials.gov NCT01243554.

Fetal Mouse Cardiovascular Imaging Using a High-frequency Ultrasound (30/45MHZ) System

Congenital heart defects (CHDs) are the most common cause of childhood morbidity and early mortality. Prenatal detection of the underlying molecular mechanisms of CHDs is crucial for inventing new preventive and therapeutic strategies. Mutant mouse models are powerful tools to discover new mechanisms and environmental stress modifiers that drive cardiac development and their potential alteration in CHDs. However, efforts to establish the causality of these putative contributors have been limited to histological and molecular studies in non-survival animal experiments, in which monitoring the key physiological and hemodynamic parameters is often absent. Live imaging technology has become an essential tool to establish the etiology of CHDs. In particular, ultrasound imaging can be used prenatally without surgically exposing the fetuses, allowing maintaining their baseline physiology while monitoring the impact of environmental stress on the hemodynamic and structural aspects of cardiac chamber development. Herein, we use the High-Frequency Ultrasound (30/45) system to examine the cardiovascular system in fetal mice at E18.5 in utero at the baseline and in response to prenatal hypoxia exposure. We demonstrate the feasibility of the system to measure cardiac chamber size, morphology, ventricular function, fetal heart rate, and umbilical artery flow indices, and their alterations in fetal mice exposed to systemic chronic hypoxia in utero in real time.

[Research advances in the mechanism of congenital heart disease induced by pregestational diabetes mellitus]

Congenital heart disease (CHD) is the most common birth defect at present and has a complex etiology which involves the combined effect of genetic and environmental factors. Pregestational diabetes mellitus is significantly associated with the development of CHD, but the detailed mechanism remains unknown. This article reviews the research advances in the molecular mechanism of CHD caused by pregestational diabetes mellitus.

A Path to Implement Precision Child Health Cardiovascular Medicine

Congenital heart defects (CHDs) affect approximately 1% of live births and are a major source of childhood morbidity and mortality even in countries with advanced healthcare systems. Along with phenotypic heterogeneity, the underlying etiology of CHDs is multifactorial, involving genetic, epigenetic, and/or environmental contributors. Clear dissection of the underlying mechanism is a powerful step to establish individualized therapies. However, the majority of CHDs are yet to be clearly diagnosed for the underlying genetic and environmental factors, and even less with effective therapies. Although the survival rate for CHDs is steadily improving, there is still a significant unmet need for refining diagnostic precision and establishing targeted therapies to optimize life quality and to minimize future complications. In particular, proper identification of disease associated genetic variants in humans has been challenging, and this greatly impedes our ability to delineate gene–environment interactions that contribute to the pathogenesis of CHDs. Implementing a systematic multileveled approach can establish a continuum from phenotypic characterization in the clinic to molecular dissection using combined next-generation sequencing platforms and validation studies in suitable models at the bench. Key elements necessary to advance the field are: first, proper delineation of the phenotypic spectrum of CHDs; second, defining the molecular genotype/phenotype by combining whole-exome sequencing and transcriptome analysis; third, integration of phenotypic, genotypic, and molecular datasets to identify molecular network contributing to CHDs; fourth, generation of relevant disease models and multileveled experimental investigations. In order to achieve all these goals, access to high-quality biological specimens from well-defined patient cohorts is a crucial step. Therefore, establishing a CHD BioCore is an essential infrastructure and a critical step on the path toward precision child health cardiovascular medicine.

The Complex Genetic Basis of Congenital Heart Defects

Twenty years ago, chromosomal abnormalities were the only identifiable genetic causes of a small fraction of congenital heart defects (CHD). Today, a de novo or inherited genetic abnormality can be identified as pathogenic in one-third of cases. We refer to them here as monogenic causes, insofar as the genetic abnormality has a readily detectable, large effect. What explains the other two-thirds? This review considers a complex genetic basis. That is, a combination of genetic mutations or variants that individually may have little or no detectable effect contribute to the pathogenesis of a heart defect. Genes in the embryo that act directly in cardiac developmental pathways have received the most attention, but genes in the mother that establish the gestational milieu via pathways related to metabolism and aging also have an effect. A growing body of evidence highlights the pathogenic significance of genetic interactions in the embryo and maternal effects that have a genetic basis. The investigation of CHD as guided by a complex genetic model could help estimate risk more precisely and logically lead to a means of prevention.