The mediating effects of gestational diabetes on fetal growth and adiposity in women who are overweight and obese: secondary analysis of the LIMIT randomised trial

Ultrasound prediction of fetal macrosomia in pregnancies complicated by diabetes mellitus: a systematic review and meta-analysis

OBJECTIVES

To report the diagnostic accuracy of ultrasound in identifying fetuses with macrosomia in pregnancies complicated by gestational or pregestational diabetes.

METHODS

Medline, Embase and Cochrane databases were searched. Inclusion criteria were singleton pregnancies complicated by diabetes undergoing third-trimester ultrasound evaluation. The index test was represented by ultrasound estimation of fetal macrosomia (estimated fetal weight EFW or abdominal circumference AC >90th or 95th percentile). Subgroup analyses were also performed. Sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio were computed using the hierarchical summary receiver-operating characteristics model.

RESULTS

Twenty studies were included in the systematic review including 8,530 pregnancies complicated by diabetes. Ultrasound showed an overall moderate accuracy in identifying fetuses with macrosomia with a sensitivity of 71.2 % (95 % CI 63.1-78.2), a specificity of 88.6 % (95 % CI 83.9-92.0). The interval between ultrasound and birth of two weeks showed the highest sensitivity and specificity (71.6 %, 95 % CI 47.9-87.3 and 91.7, 95 % CI 86.2-95.5). EFW sensitivity and specificity were 76.6 % (95 % CI 70.1-82.3) and 82.9 % (95 % CI 80.9-84.8), while AC 84.8 % (95 % CI 78.2-90.0) and 73.7 % (95 % CI 71.0-76.4).

CONCLUSIONS

Ultrasound demonstrates an overall good diagnostic accuracy in detecting fetal macrosomia in pregnancies with diabetes.

Fetal Growth and Adiposity of Infants Born Large for Gestational Age in Three Harmonized Randomized Trials

OBJECTIVE

 Infants born large for gestational age (LGA) are at an increased risk of short- and longer-term adverse outcomes. Understanding fetal growth and adiposity and their trajectories may help inform interventions to prevent birth of LGA infants. We aimed to compare fetal growth and adiposity measures of infants born LGA with those born not LGA, to determine whether the discrepancy at birth was primarily due to larger size throughout gestation, or instead to different trajectories of fetal growth.

STUDY DESIGN

 This was a secondary analysis of secondary outcomes of fetal growth and adiposity from three harmonized randomized trials-the LIMIT, GRoW, and Optimise randomized trials. These trials recruited women in early pregnancy, and a singleton gestation, from three major public metropolitan Adelaide maternity hospitals. Maternal body mass index (BMI) ranged from 18.5 to ≥40.0 kg/m2. Data were obtained from enrolled women who underwent research ultrasounds at 28 and 36 weeks' gestation. Outcome measures were ultrasound measures of fetal biometry and adiposity.

RESULTS

 Infants born LGA had larger fetal biometry measures, and higher growth trajectories, from 20 weeks' gestation. Fetal adiposity measures were consistently larger among infants born LGA and these differences increased over time. We did not find evidence that the differences in biometry and adiposity measurements varied according to maternal BMI.

CONCLUSION

 Infants born LGA had larger fetal biometry measures at all time points from 20 weeks' gestation, compared with infants born not LGA suggesting any interventions to prevent LGA likely need to commence earlier in pregnancy or prior to conception.

KEY POINTS

· Infants born LGA had larger fetal biometry measures from 20 weeks' gestation.. · Infants born LGA had larger fetal adiposity measures.. · Interventions to prevent LGA need to start earlier in pregnancy or prior to conception..

Influence of Adipose Tissue on Early Metabolic Programming: Conditioning Factors and Early Screening

BACKGROUND

Obesity and being overweight have become one of the world's most severe health issues, not only because of the pathology but also because of the development of related comorbidities. Even when children reach adulthood, the mother's environment during pregnancy has been found to have a significant impact on obesity prevention in children. Thus, both maternal dietary habits and other factors such as gestational diabetes mellitus, excessive weight gain during pregnancy, smoking, or endocrine factors, among others, could influence newborn growth, adiposity, and body composition at birth, in childhood and adolescence, hence programming health in adulthood.

METHODS

The aim of this review is to analyze the most recent human studies on the programming of fetal adipose tissue to determine which modifiable factors may influence adiposity and thus prevent specific disorders later in life by means of a bibliographic review of articles related to the subject over the last ten years.

CONCLUSIONS

The importance of a healthy diet and lifestyle not only during pregnancy and the first months of life but also throughout childhood, especially during the first two years of life as this is a period of great plasticity, where the foundations for optimal health in later life will be laid, preventing the emergence of noncommunicable diseases including obesity, diabetes mellitus type 2, hypertension, being overweight, and any other pathology linked to metabolic syndrome, which is so prevalent today, through health programs beginning at a young age.

Perception of the impact of maternal weight on pregnancy outcomes in overweight and obese women

OBJECTIVE

The purpose of this study was to assess and compare knowledge, self-awareness, and accuracy of perceived risks and weight status among overweight and obese women.

METHODS

This study was a secondary analysis of a cross-sectional questionnaire study of overweight and obese pregnant women who sought a routine first-trimester screening ultrasound. Those with a pre-pregnancy body mass index (BMI) ≥25 kg/m² (calculated using self-reported height and weight) were included. Perceived associations between estimated weight category and risk of pregnancy complications were assessed and compared in the overweight and obese groups. The perceived weight category was compared to an estimated weight category. A logistic regression identified the demographic and medical factors associated with correct identification of risk factors.

RESULTS

A total of 169 participants (88 overweight; 81 obese) were included. Most participants believed their weight did not impact the ultrasound detection of a fetal malformation (92.1% overweight vs. 55.6% obese, p < .01). Few participants associated their weight with pregnancy-related problems (6.8% overweight vs. 24.7% obese, p < .01). Most participants did not associate their weight with specific maternal complications (72.7% overweight vs. 45.7% obese, p < .01) and fetal complications (83.0% overweight vs. 71.6% obese, p = .08). More obese than overweight women underestimated their weight category (64.4% vs 41.3% overweight, p = .01). Women who correctly estimated their weight status, non-Hispanic participants, and those with a history of depression or at least one maternal co-morbidity were more likely to associate their weight with increased risk for pregnancy-related problems.

CONCLUSION

Although more obese than overweight women associated excess weight with pregnancy complications, both groups underestimated the impact on their pregnancies. Targeted educational programs are needed to improve the risk perception of these populations prior to pregnancy with the goal of improving their weight statuses and pregnancy outcomes.

Prenatal metabolomic profiles mediate the effect of maternal obesity on early childhood growth trajectories and obesity risk: the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) Study

BACKGROUND

Maternal prepregnancy obesity is an important risk factor for offspring obesity, which may partially operate through prenatal programming mechanisms.

OBJECTIVES

The study aimed to systematically identify prenatal metabolomic profiles mediating the intergenerational transmission of obesity.

METHODS

We included 450 African-American mother-child pairs from the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) Study pregnancy cohort. LC-MS was used to conduct metabolomic profiling on maternal plasma samples of the second trimester. The childhood growth outcomes of interest included BMI trajectories from birth to age 4 y (rising-high-, moderate-, and low-BMI trajectories) as well as overweight/obesity (OWO) risk at age 4 y. Mediation analysis was conducted to identify metabolite mediators linking maternal OWO and childhood growth outcomes. The potential causal effects of maternal OWO on metabolite mediators were examined using the Mendelian randomization (MR) method.

RESULTS

Among the 880 metabolites detected in the maternal plasma during pregnancy, 14 and 11 metabolites significantly mediated the effects of maternal prepregnancy OWO on childhood BMI trajectories and the OWO risk at age 4 y, respectively, and 5 mediated both outcomes. The MR analysis suggested 6 of the 20 prenatal metabolite mediators might be causally influenced by maternal prepregnancy OWO, most of which are from the pathways related to the metabolism of amino acids (hydroxyasparagine, glutamate, and homocitrulline), sterols (campesterol), and nucleotides (N2,N2-dimethylguanosine).

CONCLUSIONS

Our study provides further evidence that prenatal metabolomic profiles might mediate the effect of maternal OWO on early childhood growth trajectories and OWO risk in offspring. The metabolic pathways, including identified metabolite mediators, might provide novel intervention targets for preventing the intrauterine development of obesity in the offspring of mothers with obesity.

The association between an oral glucose tolerance test performed at term pregnancy and obstetric outcomes

Aims

Assessing the value of oral glucose tolerance test performed at term pregnancy in identifying obstetric complications.

Methods

Retrospective cohort study of women with a normal 50 g glucose challenge test who also had an oral glucose tolerance test at term (defined as at or after 37 weeks of gestation). Comparison between the pathological and normal oral glucose tolerance test groups was performed.

Results

The mean glucose in the glucose challenge test of women in the normal oral glucose tolerance test (n = 256) group was lower than that in the pathological oral glucose tolerance test (N = 16) group (105 ± 17 mg/dl (5.8 ± 0.9 mmol/l) vs 117 ± 13 mg/dl (6.5 ± 0.7 mmol/l), p = 0.007). Relevant obstetrical complications did not differ significantly between the groups. Of note, in the pathological oral glucose tolerance test group only one woman delivered a macrosomic infant.

Conclusions

A pathological oral glucose tolerance test performed at term was unable to identify women at risk for impaired glucose metabolism-related obstetric complications and is therefore of limited clinical value and seems to be unjustified.

Gestational Diabetes Mellitus and High Triglyceride Levels Mediate the Association between Pre-Pregnancy Overweight/Obesity and Macrosomia: A Prospective Cohort Study in Central China

The purpose of this study is to investigate whether the link between pre-pregnancy overweight/obesity and risk of macrosomia is mediated by both gestational diabetes mellitus (GDM) and high maternal triglyceride (mTG) levels. This prospective study finally included 29,415 singleton term pregnancies. The outcome of interest was macrosomia (≥4000 g). High mTG levels were denoted as values ≥90th percentile. GDM was diagnosed using a standard 75 g 2 h oral glucose tolerance test. The mediation analysis was conducted using log-binomial regression while controlling for maternal age, education, parity, gestational weight gain, gestational hypertension, smoking, drinking and infant sex. Overall, 15.9% of pregnant women were diagnosed with GDM, and 4.3% were macrosomia. Mediation analysis suggested that overweight had a total effect of 0.009 (95% CI, 0.006–0.013) on macrosomia, with a direct effect of 0.008 (95% CI, 0.004–0.012) and an indirect effect of 0.001 (95% CI, 0.001–0.002), with an estimated proportion of 11.1% mediated by GDM and high mTG levels together. Furthermore, we also discovered a total effect of obesity on macrosomia of 0.038 (95% CI, 0.030–0.047), consisting of a direct effect of 0.037 (95% CI, 0.028–0.045) and an indirect effect of 0.002 (95% CI, 0.001–0.002), with an estimated proportion of 5.3% mediated by GDM and high mTG levels combined. Both GDM and high mTG levels enhanced the risk of macrosomia independently and served as significant mediators in the relationship between pre-pregnancy overweight/obesity and macrosomia.

The mediating role of gestational diabetes mellitus in the associations of maternal prepregnancy body mass index with neonatal birth weight

BACKGROUND

Both prepregnancy obesity and gestational diabetes mellitus (GDM) have been linked to adverse neonatal birth weight. However, the mediating role of GDM between prepregnancy obesity and neonatal birth weight is unclear.

METHOD

The cohort study included 17 260 singleton pregnant women and their newborns. Participants' demographic characteristics, disease history, family history of the disease, and the perinatal outcomes were recorded. The association between maternal prepregnancy body mass index (BMI) status and small for gestational age (SGA) or large for gestational age (LGA) neonates was analyzed using logistic regressions, before and after adjusting for covariates and GDM. The potential mediation of GDM on the association between prepregnancy BMI and adverse birth weight was examined.

RESULT

Multivariate logistic regression demonstrated that prepregnancy underweight women were more likely to deliver SGA neonates compared to those who had normal weights, whereas prepregnancy obese pregnant women were more likely to have LGA neonates. The RMediation analyses illustrated that the mediation effect of GDM on the maternal prepregnancy BMI (continuous variable) and the risk of SGA was not significant, whereas the association between prepregnancy BMI and LGA was statistically mediated by GDM (95%CI of a*b: 0.009-0.051). The Iacobacci (2012) method indicated that the impact of maternal prepregnancy overweight (Zmediation = 2.418, P = .015) and obesity (Zmediation = 2.165, P = .030) on LGA was partially mediated by GDM, with an indirect effect of 16.3% and 13.1%, respectively.

CONCLUSION

Prepregnancy BMI was observed to be associated with SGA and LGA. The association of prepregnancy overweight and obesity with LGA was found to be partially mediated by GDM.

Comparison of ultrasound with biomarkers to identify large-for-gestational age in women screened for gestational diabetes mellitus

OBJECTIVE

Large-for-gestational-age (LGA) is associated with both fetal and maternal complications. One of the few modifiable risk factors for LGA is Gestational Diabetes Mellitus (GDM); for this reason, fetal growth is usually monitored by ultrasound in the third trimester. This prospective study compared a panel of ten established biomarkers measured at the time of selective screening for GDM at 26-28 weeks gestation with the ultrasound prediction of LGA.

METHOD

Women were recruited using convenience sampling and consented at the first antenatal visit. Women with maternal risk factors for GDM attended for the one-step 75 g oral glucose tolerance test. An additional blood sample was taken for biomarker measurement. GDM was diagnosed according to the 2013 World Health Organization (WHO) criteria. Fetal biometry, including the abdominal circumference (AC) and the fetal abdominal subcutaneous tissue (FAST) thickness, were measured at 37 weeks gestation.

RESULTS

Of the 195 women included, 105 (53.8%) had GDM. Of the 195 babies, 36 (18.5%) were LGA. Whether the woman had GDM or not, fetal biometry was strongly predictive of LGA but none of the following biomarkers measured at 26-28 weeks gestation alone or in combination were predictive: c-peptide, ghrelin, gastric inhibitory polypeptide, glucagon-like peptide-1 (GLP-1), glucagon, insulin, leptin, plasminogen activator inhibitor-1, resistin and visfatin.

CONCLUSIONS

In women diagnosed with GDM, surveillance of fetal growth to identify LGA by ultrasound should continue in the third trimester. None of the ten established maternal biomarkers measured at the time of the OGTT was as strongly predictive of LGA as ultrasound.

Association of Maternal Prepregnancy Body Mass Index With Fetal Growth and Neonatal Thalamic Brain Connectivity Among Adolescent and Young Women

Importance

Higher maternal prepregnancy body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) is associated with adverse long-term outcomes for offspring, including obesity, poorer cognitive and social abilities, and increased risk of psychiatric disorders. Less clear is whether higher maternal BMI disrupts fetal growth and brain development.

Objective

To investigate the association of maternal prepregnancy BMI with fetal growth and neonatal functional connectivity.

Design, Setting, and Participants

This prospective longitudinal cohort study was conducted from 2012 to 2017. Participants included nulliparous pregnant adolescent and young adult women, aged 14 to 19 years who were recruited in the second trimester through Columbia University Irving Medical Center and Weill Cornell Medical College. Women received routine prenatal care and had no major health problems at the time of recruitment. Data were analyzed from January 2018 to March 2020.

Exposures

Maternal prepregnancy BMI.

Main Outcomes and Measures

The main outcomes were fetal growth, measured as estimated fetal weight, and neonatal functional connectivity, measured using magnetic resonance imaging. Prepregnancy BMI and fetal ultrasonographic measurements were obtained from electronic health record review. Resting-state brain imaging data were acquired in infants within the first month of postnatal life. Functional connectivity was measured using intrinsic functional distribution and seed-based methods.

Results

Among 129 women recruited, 105 had ultrasonographic data from at least 2 points and were included in analyses. The mean (SD) age at delivery was 17.82 (1.31) years. Maternal prepregnancy BMI was positively associated with the slope of estimated fetal weight (β = 0.668; 95% CI, 0.163 to 1.175; P = .01) but not with fetal head circumference (β = -0.004; 95% CI, -0.024 to 0.016; P = .70). In a subsample of 45 infants with magnetic resonance imaging data, maternal prepregnancy BMI was positively correlated with global connectivity in the left thalamus. Using this thalamic region as a seed, higher maternal BMI was associated with greater local thalamic (both hemispheres) and lower frontothalamic connectivity.

Conclusions and Relevance

These results suggest that maternal prepregnancy BMI was associated with the development of regulation of body weight and thalamic functional brain connectivity in offspring even during fetal development.

Effect of metformin in addition to an antenatal diet and lifestyle intervention on fetal growth and adiposity: the GRoW randomised trial

BACKGROUND

The infants born to women who are overweight or obese in pregnancy are at an increased risk of being born macrosomic or large for gestational age. Antenatal dietary and lifestyle interventions have been shown to be ineffective at reducing this risk. Our aim was to examine the effects of metformin in addition to a diet and lifestyle intervention on fetal growth and adiposity among women with a BMI above the healthy range.

METHODS

Women who had a body mass index ≥25 kg/m² in early pregnancy, and a singleton gestation, were enrolled in the GRoW trial from three public maternity hospitals in metropolitan Adelaide. Women were invited to have a research ultrasounds at 28 and 36 weeks' gestation at which ultrasound measures of fetal biometry and adiposity were obtained. Fetal biometry z-scores and trajectories were calculated. Measurements and calculations were compared between treatment groups. This secondary analysis was pre-specified.

RESULTS

Ultrasound data from 511 women were included in this analysis. The difference in femur length at 36 weeks' gestation was (0.07 cm, 95% CI 0.01-0.14 cm, p = 0.019) and this was was statistically significant, however the magnitude of effect was small. Differences between treatment groups for all other fetal biometry measures, z-scores, estimated fetal weight, and adiposity measures at 28 and 36 weeks' gestation were similar.

CONCLUSIONS

The addition of metformin to dietary and lifestyle advice in pregnancy for overweight and obese women has no clinically relevant effect on ultrasound measures of fetal biometry or adiposity.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trials Registry ( ACTRN12612001277831 ).

The Influence of Preeclampsia, Advanced Maternal Age and Maternal Obesity in Neonatal Outcomes Among Women with Gestational Diabetes

OBJECTIVE

 The present study aims to analyze adverse fetal or neonatal outcomes in women with gestational diabetes, including fetal death, preterm deliveries, birthweight, neonatal morbidity and mortality, as well as the synergic effect of concomitant pregnancy risk factors and poor obstetric outcomes, as advanced maternal age, maternal obesity and pre-eclampsia in their worsening.

METHODS

 The present cohort retrospective study included all pregnant women with gestational diabetes, with surveillance and childbirth at the Hospital da Senhora da Oliveira during the years of 2017 and 2018. The data were collected from the medical electronic records registered in health informatic programs Sclinico and Obscare, and statistical simple and multivariate analysis was done using IBM SPSS Statistics.

RESULTS

 The study participants included 301 pregnant women that contributed to 7.36% of the total institution childbirths of the same years, in a total of 300 live births. It was analyzed the influence of pre-eclampsia coexistence in neonatal morbidity (p = 0.004), in the occurrence of newborns of low and very low birthweight (p < 0.01) and in preterm deliveries (p < 0.01). The influence of maternal obesity (p = 0.270; p = 0.992; p = 0.684) and of advanced maternal age in these 3 outcomes was also analyzed (p = 0,806; p = 0.879; p = 0.985).Using a multivariate analysis, the only models with statistic significance to predict the three neonatal outcomes included only pre-eclampsia (p = 0.04; p < 0.01; p < 0.01).

CONCLUSION

 Only coexistence of pre-eclampsia showed an association with adverse neonatal outcomes (neonatal morbidity, newborns of low and very low birthweight and preterm deliveries) and can be used as a predictor of them in women with gestational diabetes.

Differences in fetal fractional limb volume changes in normal and gestational diabetic pregnancies: an exploratory observational study

OBJECTIVE

Fetal fractional limb volume has been proposed as a useful measure for quantifying fetal soft tissue development. The aim of this study was to investigate the growth of fractional arm volume (AVol) and fractional thigh volume (TVol) of fetuses with maternal gestational diabetes (GDM) compared with those of fetuses with normal glucose tolerance (NGT). We hypothesised fetal fractional limb volume would be larger in the GDM group than in the NGT group in late gestation.

DESIGN

Exploratory observational study.

SETTING

Saitama Municipal Hospital.

SAMPLE

A total of 165 (125 NGT and 40 GDM) singleton Japanese pregnant women.

METHODS

AVol and TVol were assessed between 20 and 37 weeks' gestation as cylindrical limb volumes based on 50% of the fetal humeral or femoral diaphysis length. Women were diagnosed as GDM based on the criteria of the Japan Society of Obstetrics and Gynecology.

MAIN OUTCOME MEASURES

AVol and TVol were compared between women with NGT and those with GDM at each gestational age period (2-week intervals from 20 to 37 weeks' gestation).

RESULTS

Overall, 287 ultrasound scans were performed (NGT group, 205 scans; GDM group, 82 scans). There was no significant difference of AVol between the groups before 32 weeks' gestation. AVol was significantly larger in the GDM group than in the NGT group after 32 weeks' gestation (P < 0.05). TVol was not statistically different between the groups across gestation.

CONCLUSIONS

Detection of variations in fetal AVol may provide greater insight into understanding the origins of altered fetal body proportion in GDM.

TWEETABLE ABSTRACT

AVol, but not TVol, is significantly larger in fetuses with GDM than in those with NGT after 32 weeks' gestation.

Do Gestational Obesity and Gestational Diabetes Have an Independent Effect on Neonatal Adiposity? Results of Mediation Analysis from a Cohort Study in South India

Purpose

Neonates born to mothers with obesity or gestational diabetes mellitus (GDM) have an increased chance of various metabolic disorders later in life. In India, it is unclear whether maternal obesity or GDM is related to offspring adiposity. We aimed to understand the independent effect of maternal obesity and GDM with neonatal adiposity and whether GDM has a mediating effect between maternal obesity and neonatal adiposity.

Methods

We recruited a cohort of 1120 women (between April 2016 and February 2019) from the public hospitals in Bangalore, India, who voluntarily agreed to participate and provided written informed consent. The primary outcome was neonatal adiposity, defined as the sum of skinfold thickness >85^th percentile. Exposure included maternal obesity, defined as >90^th percentile of skinfold thickness. GDM, the potential mediator, was classified using the World Health Organization criteria by oral glucose tolerance test. Binary logistic regression was applied to test the effect of maternal obesity and GDM on neonatal adiposity, adjusting for potential confounders. We used Paramed command in STATA version 14 for analyzing mediating effects.

Results

We found that maternal obesity (odds ratio (OR)=2.16, 95% CI 1.46, 3.18) and GDM (OR=2.21, 95% CI1.38, 3.52) have an independent effect on neonatal adiposity. GDM significantly mediates 25.2% of the total effect between maternal obesity and neonatal adiposity, (natural direct effect OR = 1.16 95% CI 1.04, 1.30) with significant direct effect of maternal obesity (natural direct effect OR = 1.90 95% CI 1.16, 3.10) and significant total effect (OR=2.20 95% CI 1.35, 3.58).

Conclusion

We showed that maternal obesity and GDM are independently associated with offspring adiposity. Also, GDM mediates the association of maternal obesity on adiposity in children. Interventions focused on obesity prevention in women, and effective screening and management of GDM may contribute to reducing childhood obesity in India.