Obese Nondiabetic Pregnancies and High Maternal Glycated Hemoglobin at Delivery as an Indicator of Offspring and Maternal Postpartum Risks: The Prospective PEACHES Mother-Child Cohort

Reference range for glycated haemoglobin in full term non diabetic pregnant women: a multicentric cross sectional study

BACKGROUND

There are no large studies to define the normal value of glycated haemoglobin (HbA1c) measured in full term pregnant women measured at the time of delivery.

RESEARCH DESIGN AND METHODS

The study was conducted at three government hospitals in South India. Clinical data, maternal blood sample and foetal cord blood sample were collected from women admitted for safe confinement. Mean (± SD) of HbA1c in participants with no known diabetes (gestational or pregestational) or any complications (maternal or fetal) is described, 2.5th-97.5th centile reference range was derived.

RESULTS

From 3 centres, 2004 women participated in the study. Data from 1039 participants who had no history of diabetes or any maternal or fetal complication were used to determine the reference range for HbA1c at term pregnancy. The mean HbA1c in subjects devoid of diabetes and its known complications was 5.0 (± 0.39) %. The reference range for normal HbA1c at term in these women was found to be 4.3-5.9%. Maternal HbA1c at term pregnancy in non-diabetic pregnant women is associated with pre-pregnancy BMI, maternal age and 2-h plasma glucose level of 2nd trimester oral glucose tolerance test (OGTT).

CONCLUSIONS

The mean HbA1c at term pregnancy in non-diabetic women admitted for safe confinement is 5.00 (± 0.39) %. An HbA1c of 5.9% or more at term should be considered abnormal and women with such a value may be kept at a close surveillance for development of diabetes.

Fetal glycated albumin levels in offspring of obese women

OBJECTIVE

To determine the association between maternal obesity and fetal glycated albumin (GA) levels among pregnant women.

METHODS

A comparative, cross-sectional study of 59 consenting, normoglycemic, pregnant women, who met the criteria for maternal obesity, attending the antenatal clinic of the University College Hospital, Nigeria, from June 2019 to December 2019. They were recruited at 36 weeks of gestation, followed up until delivery, and compared with 58 nonobese, normoglycemic pregnant controls. At delivery, blood samples were taken from the mothers and from the umbilical cords of their newborns for serum GA assay. Maternal and newborn variables were recorded, and comparisons were made using χ² tests, independent t tests, odds ratios, analysis of variance, and Pearson correlates. Statistical significance was set at P < 0.05.

RESULTS

The odds of elevated newborn GA were 3.21 times higher in obese women compared with nonobese women (P = 0.005) and 5-min APGAR scores were higher in the newborns of nonobese women (P = 0.039). There was a significant correlation between maternal and neonatal GA for all participants (r = 0.346, P = 0.000).

CONCLUSION

These findings suggest that maternal obesity is associated with elevated fetal GA and low APGAR scores at 5 min in normoglycemic women.

Predicting the earliest deviation in weight gain in the course towards manifest overweight in offspring exposed to obesity in pregnancy: a longitudinal cohort study

BACKGROUND

Obesity in pregnancy and related early-life factors place the offspring at the highest risk of being overweight. Despite convincing evidence on these associations, there is an unmet public health need to identify "high-risk" offspring by predicting very early deviations in weight gain patterns as a subclinical stage towards overweight. However, data and methods for individual risk prediction are lacking. We aimed to identify those infants exposed to obesity in pregnancy at ages 3 months, 1 year, and 2 years who likely will follow a higher-than-normal body mass index (BMI) growth trajectory towards manifest overweight by developing an early-risk quantification system.

METHODS

This study uses data from the prospective mother-child cohort study Programming of Enhanced Adiposity Risk in CHildhood-Early Screening (PEACHES) comprising 1671 mothers with pre-conception obesity and without (controls) and their offspring. Exposures were pre- and postnatal risks documented in patient-held maternal and child health records. The main outcome was a "higher-than-normal BMI growth pattern" preceding overweight, defined as BMI z-score >1 SD (i.e., World Health Organization [WHO] cut-off "at risk of overweight") at least twice during consecutive offspring growth periods between age 6 months and 5 years. The independent cohort PErinatal Prevention of Obesity (PEPO) comprising 11,730 mother-child pairs recruited close to school entry (around age 6 years) was available for data validation. Cluster analysis and sequential prediction modelling were performed.

RESULTS

Data of 1557 PEACHES mother-child pairs and the validation cohort were analyzed comprising more than 50,000 offspring BMI measurements. More than 1-in-5 offspring exposed to obesity in pregnancy belonged to an upper BMI z-score cluster as a distinct pattern of BMI development (above the cut-off of 1 SD) from the first months of life onwards resulting in preschool overweight/obesity (age 5 years: odds ratio [OR] 16.13; 95% confidence interval [CI] 9.98-26.05). Contributing early-life factors including excessive weight gain (OR 2.08; 95% CI 1.25-3.45) and smoking (OR 1.94; 95% CI 1.27-2.95) in pregnancy were instrumental in predicting a "higher-than-normal BMI growth pattern" at age 3 months and re-evaluating the risk at ages 1 year and 2 years (area under the receiver operating characteristic [AUROC] 0.69-0.79, sensitivity 70.7-76.0%, specificity 64.7-78.1%). External validation of prediction models demonstrated adequate predictive performances.

CONCLUSIONS

We devised a novel sequential strategy of individual prediction and re-evaluation of a higher-than-normal weight gain in "high-risk" infants well before developing overweight to guide decision-making. The strategy holds promise to elaborate interventions in an early preventive manner for integration in systems of well-child care.

Late-Pregnancy Dysglycemia After Negative Testing for Gestational Diabetes and Risk of the Large-for-Gestational-Age Newborns: A Nest Case-Control Study Based on the Xi'an Longitudinal Mother-Child Cohort Study

BACKGROUND

The implications of gestational diabetes mellitus (GDM) on the short- and long-term health outcomes of both mother and child have been extensively studied. However, studies related to negative Oral Glucose Tolerance Test (OGTT) results in the second trimester but dysglycemia in late pregnancy on maternal and infant pregnancy outcomes are rare.

METHODS

We conducted a nest case-control study within the Xi'an Longitudinal Mother-Child Cohort study (XAMC) to investigate the risk of adverse pregnancy outcomes in mothers and children with maternal negative mid-pregnancy OGTT results but high glycated hemoglobin (HbA_1c) levels (≥5.7%) in late pregnancy. All target women who delivered from January 1st, 2017 to December 31st, 2018 in Northwest Women's and Children's Hospital in Xi'an were enrolled as the case group (HbA_1c ≥ 5.7%). Others with HbA_1c < 5.7% but without GDM were selected as the control group (HbA_1c < 5.7%) by matching with the same delivery period. The logistic regression models were used to find out the risk factors of adverse pregnancy outcomes in the target population.

RESULTS

A total of 2,116 and 1,907 women were finally enrolled in the case and control groups, respectively. Compared to the control group, more newborns with macrosomia (9.2% vs 4.1%, P < 0.001) and large for gestational age (LGA) (23.7% vs. 13.5%, P < 0.001), but less small for gestational age (SGA) (4.4% vs. 6.1%, P = 0.017) were found in the case group. The differences in other outcomes were not statistically significant. The multiple logistic regression analysis showed that gestational age, fetal length, prenatal HbA_1c, and total cholesterol (TG) were independent risk factors for newborns with large-for-gestational-age (LGA). The case group had a 2.516-fold (95% CI, 1.692-3.739) risk of delivering LGA newborns compared to the control group.

CONCLUSION

The glycemic management during the late pregnancy of non-GDM women should be given special consideration to reduce the risk of overweight offspring at birth.

Human Milk Oligosaccharides in Cord Blood Are Altered in Gestational Diabetes and Stimulate Feto-Placental Angiogenesis In Vitro

(1) Background: Human milk oligosaccharides (HMOs) are present in maternal serum during pregnancy and their composition is altered in gestational diabetes (GDM). HMOs are also in fetal cord blood and in contact with the feto-placental endothelium, potentially affecting its functions, such as angiogenesis. We hypothesized that cord blood HMOs are changed in GDM and contribute to increased feto-placental angiogenesis, hallmark of GDM. (2) Methods: Using HPLC, we quantified HMOs in cord blood of women with normal glucose tolerance (NGT, n = 25) or GDM (n = 26). We investigated in vitro angiogenesis using primary feto-placental endothelial cells (fpECs) from term placentas after healthy pregnancy (n = 10), in presence or absence of HMOs (100 µg/mL) isolated from human milk, 3′-sialyllactose (3′SL, 30 µg/mL) and lactose (glycan control) and determined network formation (Matrigel assay), proliferation (MTT assays), actin organization (F-actin staining), tube formation (fibrin tube formation assay) and sprouting (spheroid sprouting assay). (3) Results: 3′SL was higher in GDM cord blood. HMOs increased network formation, HMOs and 3’SL increased proliferation and F-actin staining. In fibrin assays, HMOs and 3’SL increased total tube length by 24% and 25% (p < 0.05), in spheroid assays, by 32% (p < 0.05) and 21% (p = 0.056), respectively. Lactose had no effect. (4) Conclusions: Our study suggests a novel role of HMOs in feto-placental angiogenesis and indicates a contribution of HMO composition to altered feto-placental vascularization in GDM.

Longitudinal Association of Maternal Pre-Pregnancy BMI and Third-Trimester Glycemia with Early Life Growth of Offspring: A Prospective Study among GDM-Negative Pregnant Women

Intrauterine modifiable maternal metabolic factors are essential to the early growth of offspring. The study sought to evaluate the associations of pre-pregnancy BMI and third-trimester fasting plasma glucose (FPG) with offspring growth outcomes within 24 months among GDM-negative pregnant women. Four hundred eighty-three mother –offspring dyads were included from the Shanghai Maternal-Child Pairs Cohort. The pregnant women were categorized into four mutually exclusive groups according to pre-pregnancy BMI as normal or overweight/obesity and third-trimester FPG as controlled or not controlled. Offspring growth in early life was indicated by the BAZ (BMI Z-score), catch-up growth, and overweight/obesity. Among those with controlled third-trimester FPG, pre-pregnancy overweight/obesity significantly increased offspring birth weight, BAZ, and risks of overweight/obesity (RR 1.83, 95% CI 1.23 to 2.73) within 24 months. Those who had uncontrolled third-trimester FPG had a reduced risk of offspring overweight/obesity within 24 months by 47%. The combination of pre-pregnancy overweight/obesity and maternal uncontrolled third-trimester FPG increased 5.24-fold risk of offspring catch-up growth within 24 months (p < 0.05). Maternal pre-pregnancy overweight/obesity and uncontrolled third-trimester glycemia among GDM-negative women both have adverse effects on offspring growth within 24 months. With the combination of increasing pre-pregnancy BMI and maternal third-trimester FPG, the possibility of offspring catch-up growth increases.

A Review on Research Progress in the Application of Glycosylated Hemoglobin and Glycated Albumin in the Screening and Monitoring of Gestational Diabetes

Glycosylated hemoglobin (HbA1C) and glycated albumin (GA) can be used for blood glucose management of a person with diabetes as a result of their convenience and stability. However, there is no corresponding standard for the application of glycosylated hemoglobin and glycosylated albumin in gestational diabetes mellitus (GDM). In this review, we summarize the published research and discuss three aspects of the significance of HBA1C and GA in GDM patients: screening of gestational diabetes mellitus, blood glucose monitoring and the relationship with pregnancy outcome. At present, studies suggest that HBA1C can be used as a screening indicator for pregnant women, but it cannot completely replace OGTT. HbA1C and GA can be used for blood glucose management in patients with GDM to reduce the incidence of GDM complications. However, the application of HBA1C and GA in GDM still needs more research and clinical practice support.

Neonatal antibiotic exposure impairs child growth during the first six years of life by perturbing intestinal microbial colonization

Exposure to antibiotics in the first days of life is thought to affect various physiological aspects of neonatal development. Here, we investigate the long-term impact of antibiotic treatment in the neonatal period and early childhood on child growth in an unselected birth cohort of 12,422 children born at full term. We find significant attenuation of weight and height gain during the first 6 years of life after neonatal antibiotic exposure in boys, but not in girls, after adjusting for potential confounders. In contrast, antibiotic use after the neonatal period but during the first 6 years of life is associated with significantly higher body mass index throughout the study period in both boys and girls. Neonatal antibiotic exposure is associated with significant differences in the gut microbiome, particularly in decreased abundance and diversity of fecal Bifidobacteria until 2 years of age. Finally, we demonstrate that fecal microbiota transplant from antibiotic-exposed children to germ-free male, but not female, mice results in significant growth impairment. Thus, we conclude that neonatal antibiotic exposure is associated with a long-term gut microbiome perturbation and may result in reduced growth in boys during the first six years of life while antibiotic use later in childhood is associated with increased body mass index.

Contributing Factors to Perinatal Outcome in Pregnancies with Gestational Diabetes-What Matters Most? A Retrospective Analysis

The aim of diabetes care of pregnant women with gestational diabetes mellitus (GDM) is to attain pregnancy outcomes including rates of large-for-gestational-age (LGA) newborns, pre-eclampsia, C-sections (CS) and other neonatal outcomes similar to those of the non-GDM pregnant population. Obesity and excessive weight gain during pregnancy have been shown to also impact perinatal outcome. Since GDM is frequently associated with elevated body mass index (BMI), we evaluated the impact of maternal prepregnancy BMI, development of GDM and gestational weight gain (GWG) during pregnancy on perinatal outcome. We compared 614 GDM patients with 5175 non-diabetic term deliveries who gave birth between 2012 and 2016. Multivariate regression analysis was used to evaluate the independent contribution of each factor on selected perinatal outcome variables. Additionally, subgroup analysis for obese (BMI ≥ 30 kg/m²) and non-obese women (BMI < 30 kg/m²) was performed. LGA was significantly influenced by BMI, GWG and GDM, while Neonatal Intensive Care Unit (NICU) admission was solely impacted by GDM. Maternal outcomes were not dependent on GDM but on GWG and prepregnancy BMI. These results remained significant in the non-obese subgroup only. Thus, GDM still affects perinatal outcomes and requires further improvement in diabetic care and patient counseling.

Diabetes and obesity during pregnancy are associated with oxidative stress genotoxicity in newborns

Objective To compare the level of oxidative deoxyribonucleic acid (DNA) damage (genotoxicity) between the offspring of mothers with and without diabetes diagnosed during pregnancy and its association with maternal body mass index (BMI). Methods We measured 8-hydroxy-deoxyguanosine (8-OH-dG), a marker of DNA oxidative damage, in venous umbilical cord plasma from newborns of mothers with (n=34) and without (n=56) diabetes diagnoses obtained during pregnancy. Two markers of oxidative stress - namely, nitric oxide degradation products (NOx) and total glutathione (GSH) - were quantified in both mothers and newborns. The effects of BMI, glycated hemoglobin (HbA1c), age and delivery mode were also analyzed. Results Newborns of mothers with diabetes during pregnancy exhibited higher levels of 8-OH-dG than those of mothers without diabetes (P<0.001). The other markers of oxidative stress were also higher in both mothers with diabetes and their newborns, with the exception of NOx in the mothers. The association of diabetes with 8-OH-dG was independent of other analyzed factors. Conclusion The offspring of mothers with diabetes during pregnancy are born with increased genotoxicity than the offspring of mothers without diabetes. BMI and HbA1c display an independent association with 8-OH-dG, particularly in the offspring of mothers not diagnosed with diabetes.

Late-pregnancy dysglycemia in obese pregnancies after negative testing for gestational diabetes and risk of future childhood overweight: An interim analysis from a longitudinal mother-child cohort study

BACKGROUND

Maternal pre-conception obesity is a strong risk factor for childhood overweight. However, prenatal mechanisms and their effects in susceptible gestational periods that contribute to this risk are not well understood. We aimed to assess the impact of late-pregnancy dysglycemia in obese pregnancies with negative testing for gestational diabetes mellitus (GDM) on long-term mother-child outcomes.

METHODS AND FINDINGS

The prospective cohort study Programming of Enhanced Adiposity Risk in Childhood-Early Screening (PEACHES) (n = 1,671) enrolled obese and normal weight mothers from August 2010 to December 2015 with trimester-specific data on glucose metabolism including GDM status at the end of the second trimester and maternal glycated hemoglobin (HbA1c) at delivery as a marker for late-pregnancy dysglycemia (HbA1c ≥ 5.7% [39 mmol/mol]). We assessed offspring short- and long-term outcomes up to 4 years, and maternal glucose metabolism 3.5 years postpartum. Multivariable linear and log-binomial regression with effects presented as mean increments (Δ) or relative risks (RRs) with 95% confidence intervals (CIs) were used to examine the association between late-pregnancy dysglycemia and outcomes. Linear mixed-effects models were used to study the longitudinal development of offspring body mass index (BMI) z-scores. The contribution of late-pregnancy dysglycemia to the association between maternal pre-conception obesity and offspring BMI was estimated using mediation analysis. In all, 898 mother-child pairs were included in this unplanned interim analysis. Among obese mothers with negative testing for GDM (n = 448), those with late-pregnancy dysglycemia (n = 135, 30.1%) had higher proportions of excessive total gestational weight gain (GWG), excessive third-trimester GWG, and offspring with large-for-gestational-age birth weight than those without. Besides higher birth weight (Δ 192 g, 95% CI 100-284) and cord-blood C-peptide concentration (Δ 0.10 ng/ml, 95% CI 0.02-0.17), offspring of these women had greater weight gain during early childhood (Δ BMI z-score per year 0.18, 95% CI 0.06-0.30, n = 262) and higher BMI z-score at 4 years (Δ 0.58, 95% CI 0.18-0.99, n = 43) than offspring of the obese, GDM-negative mothers with normal HbA1c values at delivery. Late-pregnancy dysglycemia in GDM-negative mothers accounted for about one-quarter of the association of maternal obesity with offspring BMI at age 4 years (n = 151). In contrast, childhood BMI z-scores were not affected by a diagnosis of GDM in obese pregnancies (GDM-positive: 0.58, 95% CI 0.36-0.79, versus GDM-negative: 0.62, 95% CI 0.44-0.79). One mechanism triggering late-pregnancy dysglycemia in obese, GDM-negative mothers was related to excessive third-trimester weight gain (RR 1.72, 95% CI 1.12-2.65). Furthermore, in the maternal population, we found a 4-fold (RR 4.01, 95% CI 1.97-8.17) increased risk of future prediabetes or diabetes if obese, GDM-negative women had a high versus normal HbA1c at delivery (absolute risk: 43.2% versus 10.5%). There is a potential for misclassification bias as the predominantly used GDM test procedure changed over the enrollment period. Further studies are required to validate the findings and elucidate the possible third-trimester factors contributing to future mother-child health status.

CONCLUSIONS

Findings from this interim analysis suggest that offspring of obese mothers treated because of a diagnosis of GDM appeared to have a better BMI outcome in childhood than those of obese mothers who-following negative GDM testing-remained untreated in the last trimester and developed dysglycemia. Late-pregnancy dysglycemia related to uncontrolled weight gain may contribute to the development of child overweight and maternal diabetes. Our data suggest that negative GDM testing in obese pregnancies is not an "all-clear signal" and should not lead to reduced attention and risk awareness of physicians and obese women. Effective strategies are needed to maintain third-trimester glycemic and weight gain control among otherwise healthy obese pregnant women.

BMI-Independent Effects of Gestational Diabetes on Human Placenta

PURPOSE

Recently, alterations in maternal lipid metabolism were associated with gestational diabetes mellitus (GDM). However, detailed plasma lipid profiles and their relevance for placental and fetal metabolism are currently not understood.

METHODS

Maternal and placental lipid profiles were characterized in women with GDM and women with normal glucose tolerance (NGT). Inflammatory gene expression was compared in placentas and primary term trophoblasts between the groups. In addition, trophoblasts were stimulated with nonesterified fatty acids (NEFAs), and effects on gene expression were quantified. Finally, placental macrophage content and cord blood concentrations of inflammatory parameters and NEFAs were compared between women with GDM and women with NGT with similar body mass index (BMI).

RESULTS

Palmitate and stearate levels were elevated in both maternal plasma and placental tissue of women with GDM. Placental GDM-associated elevations of IL6, IL8, and TLR2 expression were reflected in trophoblasts derived from women with GDM. Stimulation of primary trophoblasts with palmitate led to increased mRNA expression and protein release of the cytokine IL6 and the chemokine IL8. In line with this, elevated amounts of CD68-positive cells were quantified in the placental tissue of women with GDM. No GDM-associated elevations in a range of inflammatory parameters and NEFAs in cord blood of NGT vs GDM neonates was found.

CONCLUSIONS

GDM, independently of BMI, altered maternal plasma NEFAs and the placental lipid profile. GDM was associated with trophoblast and whole-placenta lipoinflammation; however, this was not accompanied by elevated concentrations of inflammatory cytokines or NEFAs in neonatal cord blood.

Maternal overweight is not an independent risk factor for increased birth weight, leptin and insulin in newborns of gestational diabetic women: observations from the prospective 'EaCH' cohort study

BACKGROUND

Both gestational diabetes mellitus (GDM) as well as overweight/obesity during pregnancy are risk factors for detrimental anthropometric and hormonal neonatal outcomes, identified to 'program' adverse health predispositions later on. While overweight/obesity are major determinants of GDM, independent effects on critical birth outcomes remain unclear. Thus, the aim of the present study was to evaluate, in women with GDM, the relative/independent impact of overweight/obesity vs. altered glucose metabolism on newborn parameters.

METHODS

The prospective observational 'Early CHARITÉ (EaCH)' cohort study primarily focuses on early developmental origins of unfavorable health outcomes through pre- and/or early postnatal exposure to a 'diabetogenic/adipogenic' environment. It includes 205 mother-child dyads, recruited between 2007 and 2010, from women with treated GDM and delivery at the Clinic of Obstetrics, Charité - Universitätsmedizin Berlin, Germany. Recruitment, therapy, metabolite/hormone analyses, and data evaluation were performed according to standardized guidelines and protocols. This report specifically aimed to identify maternal anthropometric and metabolic determinants of anthropometric and critical hormonal birth outcomes in 'EaCH'.

RESULTS

Group comparisons, Spearman's correlations and unadjusted linear regression analyses initially confirmed that increased maternal prepregnancy body-mass-index (BMI) is a significant factor for elevated birth weight, cord-blood insulin and leptin (all P < 0.05). However, consideration of and adjustment for maternal glucose during late pregnancy showed that no maternal anthropometric parameter (weight, BMI, gestational weight gain) remained significant (all n.s.). In contrast, even after adjustment for maternal anthropometrics, third trimester glucose values (fasting and postprandial glucose at 32nd and 36th weeks' gestation, HbA1c in 3rd trimester and at delivery), were clearly positively associated with critical birth outcomes (all P < 0.05).

CONCLUSIONS

Neither overweight/obesity nor gestational weight gain appear to be independent determinants of increased birth weight, insulin and leptin. Rather, 3rd trimester glycemia seems to be crucial for respective neonatal outcomes. Thus, gestational care and future research studies should greatly consider late pregnancy glucose in overweight/obese women with or without GDM, for evaluation of critical causes and interventional strategies against 'perinatal programming of diabesity' in the offspring.