The influence of maternal glucose metabolism on fetal growth, development and morbidity in 917 singleton pregnancies in nondiabetic women

Associations between capillary glucose during pregnancy and childhood growth to the age of five: a cohort study

The objective of this study was to evaluate the relationship between random capillary glucose levels in healthy pregnant women and infant size at birth and childhood growth to the age of five years. This population-based cohort study comprised 10,937 healthy mother-child dyads. Data on highest maternal random capillary glucose level during pregnancy and sequential anthropometric data on their children during the first five years of life were gathered from the Uppsala County Mother and Child Cohort. Statistical analyses were performed with linear regression and linear mixed effect regression models. We found that higher glucose level during pregnancy was associated with higher weight z-score (β 0.10, 95% confidence interval (CI) 0.08-0.11), length z-score (β 0.05, 95% CI 0.03-0.07) and BMI z-score (β 0.09, 95% CI 0.07-0.12) at birth, adjusted for maternal BMI and country of birth, smoking during pregnancy and parity. The association did not remain at 1½, 3, 4 and 5 years of age. There was a positive relationship between higher glucose level during pregnancy and a decrease in weight z-score, height z-score and BMI z-score from birth to 5 years of age. In conclusion, higher random capillary glucose levels in pregnant healthy women were associated with greater infant size at birth, as well as decreased growth velocity in early childhood.

Children Born Small for Gestational Age: Differential Diagnosis, Molecular Genetic Evaluation, and Implications

Children born small for gestational age (SGA), defined as a birth weight and/or length below -2 SD score (SDS), comprise a heterogeneous group. The causes of SGA are multifactorial and include maternal lifestyle and obstetric factors, placental dysfunction, and numerous fetal (epi)genetic abnormalities. Short-term consequences of SGA include increased risks of hypothermia, polycythemia, and hypoglycemia. Although most SGA infants show catch-up growth by 2 years of age, ∼10% remain short. Short children born SGA are amenable to GH treatment, which increases their adult height by on average 1.25 SD. Add-on treatment with a gonadotropin-releasing hormone agonist may be considered in early pubertal children with an expected adult height below -2.5 SDS. A small birth size increases the risk of later neurodevelopmental problems and cardiometabolic diseases. GH treatment does not pose an additional risk.

Masked hypoglycemia in pregnancy

BACKGROUND

Hypoglycemia is a major hindrance for optimal glycemic control in women with gestational diabetes mellitus (GDM) on insulin. In the present study, masked hypoglycemia (glucose <2.77mmol/L for ≥30 min) was estimated in pregnant women using a continuous glucose monitoring (CGM) system.

METHODS

Twenty pregnant women with GDM on insulin (cases) and 10 age-matched euglycemic pregnant women (controls) between 24 and 36 weeks gestation were recruited. Both groups performed self-monitoring of blood glucose (SMBG) and underwent CGM for 72 h to assess masked hypoglycemia. Masked hypoglycemic episodes were further stratified into two groups based on interstitial glucose (2.28-2.77 and ≤2.22 mmol/L).

RESULTS

Masked hypoglycemia was recorded in 35% (7/20) of cases and 40% (4/10) of controls using CGM, with an average of 1.28 and 1.25 episodes per subject, respectively. Time spent at glucose levels between 2.28 and 2.77 mmol/L did not differ between the two groups (mean 114 vs 90 min; P = 0.617), but cases spent a longer time with glucose ≤2.2 mmol/L. Babies born to women with GDM were significantly lighter than those born to controls (2860 vs 3290 g; P = 0.012). There was no significant difference in birth weight within the groups among babies born to women with or without hypoglycemia.

CONCLUSION

Euglycemic pregnant women and those with GDM on insulin had masked hypoglycemia. Masked hypoglycemia was not associated with adverse maternal or fetal outcomes. Therefore, low glucose levels in the hypoglycemic range may represent a physiologic adaptation in pregnancy. This response is exaggerated in women with GDM on insulin.

Nutrition for Multiples

In 2012 there were 135,943 infants of multiple pregnancies born in the United States, nearly a 2-fold increase since 1980, with twins accounting for 96% of all multiple births. To date, most perinatal morbidities associated with multiple births have proven resistant to technological or pharmaceutical interventions. Maternal nutrition can have a profound effect on the course and outcome of multiple pregnancy, with the goal of achieving optimal intrauterine growth and birthweights, and minimizing prenatal and perinatal complications for the mother and her children.

2-Hour postload serum glucose levels and maternal blood pressure as independent predictors of birth weight in "appropriate for gestational age" neonates in healthy nondiabetic pregnancies

INTRODUCTION

Increased neonatal birth weight (NBW), often associated with diabetic pregnancies, is a recognized indicator of childhood obesity and future metabolic risk. Predictors of NBW in healthy non-diabetic pregnancies are not yet established. Here, we investigated the association of maternal parameters of healthy non-diabetic mothers with NBW of their "appropriate-for-gestational age" neonates.

METHODS

The study involved 36 healthy mother/infant pairs. Examined parameters included NBW, maternal age, first and last trimester (BMI), weight gain, fasting serum lipids and glucose, 2-hour postload glucose levels and blood pressure.

RESULTS

Postload-glucose levels were significantly higher in mothers of heavier neonates. ANOVA results indicated that 15% increase in postload-glucose levels corresponded to more than 0.5 Kg increase in NBW in the third tertile. NBW correlated positively with postload glucose levels, and negatively with systolic blood pressure. Regression analysis showed that the main predictors of NBW were postload-glucose levels (B = 0.455, P = 0.003), followed by systolic blood pressure (B = -0.447, P = 0.004), together predicting 31.7% NBW variation.

CONCLUSION

This study highlights that increased maternal postload sugar levels and blood pressure, within the normal range, highly predicts NBW of healthy mothers. These findings may provide focus for early dietary intervention measures to avoid future risks to the mother and baby.

Effect of maternal anthropometry and metabolic parameters on fetal growth

OBJECTIVE

The aim of this study was to determine the effect of maternal anthropometry and metabolic parameters on neonatal anthropometry.

MATERIALS AND METHODS

This observational cross-sectional study was conducted from January 2008 to June 2009 at a single tertiary care center. Maternal anthropometry and metabolic parameters like fasting serum insulin, lipid profile, and random blood glucose were estimated in 50 pregnant women at term. Detailed anthropometry of the neonates was performed.

RESULTS

Large for gestational age (LGA) babies had higher maternal body mass index (BMI), fasting serum insulin, and cord blood insulin levels, and lower maternal high density lipoprotein (HDL) compared to appropriate for gestational age (AGA) group (P < 0.001). Among the maternal parameters, BMI, gestational age, fasting serum insulin, and random blood sugar (RBS) had significant positive correlation, while HDL had negative correlation with birth weight (P < 0.05). However, only maternal BMI was the significant predictor of neonatal birth weight on multiple regression analysis (ß = 0.340, P = 0.01).

CONCLUSION

The BMI of glucose-tolerant mother is more important than metabolic parameters in determining the birth weight of term babies.

Dietary intake in pregnant women in a Spanish Mediterranean area: as good as it is supposed to be?

OBJECTIVE

To assess food and nutrient intakes and compliance with nutritional recommendations in pregnant women according to selected sociodemographic characteristics.

DESIGN

Cross-sectional study based on data from the INMA-Valencia cohort (Spain), which recruited pregnant women between 2004 and 2005. Information on maternal sociodemographics and anthropometry was collected. Dietary intake was assessed through an FFQ. Intakes of foods were compared with Spanish food-based dietary guidelines. Intake inadequacy for nutrients was assessed using the Dietary Reference Intakes of the US Institute of Medicine.

SETTING

Valencia, Spain.

SUBJECTS

We studied 822 pregnant women who had information on dietary intake during their first trimester of pregnancy.

RESULTS

More than 50% of pregnant women did not meet the guidelines for cereals and legumes; reported intakes of carbohydrates, n-3 and n-6 fatty acids were below recommendations and exceeded the total fat intake according to dietary references. Dietary inadequacy for folate, Fe and vitamin E ranged from 99% to 68%. Vegetable intake was related to age only. Younger and less educated women showed lower intakes of protein and n-3 fatty acids and higher intakes of trans-fatty acids as well as greater inadequacy for micronutrients. Spanish women reported lower intakes of fruit and carbohydrates and higher intakes of protein, total fat, SFA, MUFA and n-3 fatty acids compared with their foreign-born counterparts.

CONCLUSIONS

Women in the studied area have inadequate intakes of several nutrients relevant during pregnancy. Age, education and country of origin are factors significantly related to dietary intake and adequacy.

Glycosylated hemoglobin level in the second trimester predicts birth weight and amniotic fluid volume in non-diabetic pregnancies with abnormal screening test

OBJECTIVE

To investigate relationship between glycemic control in first half of pregnancy by measuring mid-pregnancy HbA1c and neonatal birth weight and amniotic fluid volume.

METHODS

We prospectively enrolled 220 pregnant women who received oral glucose tolerance test (OGTT) after positive gestational diabetes mellitus screening. We included 102 women with normal OGTT results into final analysis. We measured birth weight and amniotic fluid index (AFI) at 32-34 weeks.

RESULTS

Mean birth weight was 3313±426 g, and 15.7% of neonates were classified as large-for-gestational age (LGA). Mean Hb1Ac was 4.96±0.28%. Median AFI was 145 mm, and polyhydramnios rate was 2.9%. Birth weight was positively correlated with HbA1c level (r=0.373, p<0.001) and pre-pregnancy body mass index (BMI; r=0.351, p<0.001). Linear regression analysis showed that HbA1c and pre-pregnancy BMI were positive independent determinants of neonatal birth weight, and HbA1c was positive independent determinant of AFI. Receiver operating characteristics curve identified HbA1c level of 4.99 as optimal threshold for prediction of LGA with 93.8% sensitivity, 61.6% specificity and positive likelihood ratio (+LR) of 2.45 and pre-pregnancy BMI value of 25.2 as optimal threshold for prediction of LGA with 81.3% sensitivity, 57% specificity and +LR of 1.9.

CONCLUSION

In non-diabetic pregnant women with abnormal screening test, mid-pregnancy HbA1c level and pre-pregnancy BMI may predict neonatal birth weight. AFI in 32-34 weeks of gestation is related with mid-pregnancy HbA1c level.

Maternal glycemia and risk of large-for-gestational-age babies in a population-based screening

OBJECTIVE

Gestational diabetes is a risk factor for large-for-gestational-age (LGA) newborns, but many LGA babies are born to mothers with normal glucose tolerance. We aimed to clarify the association of maternal glycemia across the whole distribution with birth weight and risk of LGA births in mothers with normal glucose tolerance.

RESEARCH DESIGN AND METHODS

We undertook a population-based gestational diabetes screening in an urban area of Hungary in 2002-2005. All singleton pregnancies of mothers >or=18 years of age, without known diabetes or gestational diabetes (World Health Organization criteria) and data on a 75-g oral glucose tolerance test at 22-30 weeks of gestation, were included (n = 3,787, 78.9% of the target population). LGA was determined as birth weight greater than the 90th percentile using national sex- and gestational age-specific charts.

RESULTS

Mean +/- SD maternal age was 30 +/- 4 years, BMI was 22.6 +/- 4.0 kg/m(2), fasting blood glucose was 4.5 +/- 0.5 mmol/l, and postload glucose was 5.5 +/- 1.0 mmol/l. The mean birth weight was 3,450 +/- 476 g at 39.2 +/- 1.2 weeks of gestation. There was a U-shaped association of maternal fasting glucose with birth weight (P(curve) = 0.004) and risk of having an LGA baby (lowest values between 4 and 4.5 mmol/l, P(curve) = 0.0004) with little change after adjustments for clinical characteristics. The association of postload glucose with birth weight (P = 0.03) and the risk of an LGA baby (P = 0.09) was weaker and linear.

CONCLUSIONS

Both low and high fasting glucose values at 22-30 weeks of gestation are associated with increased risk of an LGA newborn. We suggest that the excess risk related to low glucose reflects the increased use of nutrients by LGA fetuses that also affects the mothers' fasting glucose.

Glucose tolerance in pregnancy and the long-term risk of cardiovascular disease

BACKGROUND

Studies demonstrate an association between high but non-diabetic blood glucose levels and cardiovascular morbidity and mortality. Pregnancy alters glucose metabolism and results in a continuum of glucose tolerance, it is not known whether this continuum is associated with a continuum of risk of CVD in later life.

OBJECTIVES

To examine the long-term risk of CVD associated with the continuum of maternal glucose tolerance.

PARTICIPANTS

Nine hundred and seventeen participants assessed during pregnancy and followed over 20 years.

MEASUREMENTS

Smoking behaviour, BMI at index pregnancy and follow-up, and gestational HbA1c.

MAIN OUTCOME

Requiring medication for hypertension and CVD, and hospital admissions for CVD as ascertained by record linkage over 20-year period.

RESULTS

Fifty-one women had a history of CVD, 85 women had hypertension and 17 women (2.3%) were admitted for CVD. There was a significant increase in the risk for CVD, hypertension and hospitalisation for CVD across the quartiles of gestational HbA1c after adjustment for known risk factors. This increased risk reached statistical significance in the highest quartile although confidence intervals were wide.

CONCLUSION

Sub-clinical HbA1c during pregnancy was associated with a dose-related increase in the presence of medication and hospital admission for CVD. The magnitude of these effects is of note.

Glucose kinetics and pregnancy outcome in Indian women with low and normal body mass indices

BACKGROUND/OBJECTIVES

Fetal energy demands are met from the oxidation of maternally supplied glucose and amino acids. During the fasted state, the glucose supply is thought to be met by gluconeogenesis. Underweight women with low body mass index (BMI) might be unable to adequately supply amino acids to satisfy the demands of gluconeogenesis.

SUBJECTS/METHODS

Glucose kinetics were measured during the first and second trimesters of pregnancy in 10 low-BMI and 10 normal-BMI pregnant women at the 12th hour of an overnight fast using a primed 6 h U-(13)C glucose infusion and was correlated to maternal dietary and anthropometric variables and birth weight.

RESULTS

Low-BMI mothers consumed more energy, carbohydrates and protein, had faster glucose production (R (a)) and oxidation rates in the first trimester. In the same trimester, dietary energy and carbohydrate correlated with glucose production, glycogenolysis and glucose oxidation in all women. Both groups had similar rates of gluconeogenesis in the first and second trimesters. Glucose R (a) in the second trimester was weakly correlated with the birth weight (r=0.4, P=0.07).

CONCLUSIONS

Maternal energy and carbohydrate intakes, not BMI, appear to influence glucose R (a) and oxidation in early and mid pregnancy.

[Overweight in adolescent offspring of women with hyperglycemia during pregnancy]

AIM

To verify whether different hyperglycemia levels during pregnancy cause frequency differences in adolescent obesity and its morbidities in the offspring.

METHODS

Seventy-three children were divided into three groups according to maternal glucose tolerance: G1 (n=27) normal oral glucose tolerance test (OGTT) and daily glycemia (DG); G2 (n=23) normal OGTT and high DG; G3 (n=23) abnormal OGTT and DG (gestational diabetes mellitus; GDM). All underwent clinical evaluation (anthropometry) a questionnaire(neonatal data, eating habits), and determination of fasting serum glucose and lipid profile measurement. Analysis of variance (ANOVA) and the Goodmans test were used to compare the groups.

RESULTS

G3 mothers showed higher fasting plasma glucose(FPG) and DG than G2 and G1(FPG: 93+/-10 vs 83+/-5 vs 78+/-10 mg/dL; DG: 104+/-12 vs 93+/-7 vs 85+/-9 mg/dL, respectively; P<0.001). G2 mothers had higher DG than G1 (93+/-7 vs 85+/-9 mg/dL; P<0.001). G3 offspring birthweight was higher than G1 and G2 (3,667+/-527 vs 3,167+/-565 and 3,282+/-401 g, respectively; P<0.05). More G3 offspring were overweight than G1 (52.2 vs 14.8%; P<0.05).

CONCLUSIONS

Offspring of GDM mothers with fasting and daily hyperglycemia have higher birthweight and overweight frequency in adolescence. These children must be followed up from infancy.

Prediabetes and the big baby

The concept of prediabetes has come to the fore again with the worldwide epidemic of Type 2 diabetes. The careful observations of W. P. U. Jackson and his colleagues in Cape Town, South Africa 50 years ago still deserve attention. Maternal hyperglycaemia cannot be the only cause of fetal macrosomia, and the pathophysiological reason for the unexplained stillbirth in late diabetic pregnancy still eludes us. The biochemical concepts of 'facilitated anabolism' and 'accelerated starvation' were developed by Freinkel as explanations of the protective mechanisms for the baby during the stresses of pregnancy. Some of these nutritional stresses may also occur in the particular form of early childhood malnutrition known in Africa as kwashiorkor, where subcutaneous fat deposition, carbohydrate intolerance, islet hyperplasia and sudden death may follow a period of excess carbohydrate and deficient protein intake. Different feeding practices in different parts of the world make comparisons uncertain, but there is evidence for insulin resistance in both the macrosomic fetus of the hyperglycaemic mother and in the child with established kwashiorkor. These adaptive changes in early development may play both a physiological and a pathological role. Worldwide studies of hyperglycaemia in pregnancy are gradually establishing acceptable diagnostic criteria, appropriate screening procedures and an evidence base for treatment. Nevertheless the challenge of prediabetes and the big baby is still with us--in Jackson's words--'diabetes mellitus is a fascinating condition-the more we know about it the less we understand it'.

Type 2 diabetes TCF7L2 risk genotypes alter birth weight: a study of 24,053 individuals

The role of genes in normal birth-weight variation is poorly understood, and it has been suggested that the genetic component of fetal growth is small. Type 2 diabetes genes may influence birth weight through maternal genotype, by increasing maternal glycemia in pregnancy, or through fetal genotype, by altering fetal insulin secretion. We aimed to assess the role of the recently described type 2 diabetes gene TCF7L2 in birth weight. We genotyped the polymorphism rs7903146 in 15,709 individuals whose birth weight was available from six studies and in 8,344 mothers from three studies. Each fetal copy of the predisposing allele was associated with an 18-g (95% confidence interval [CI] 7-29 g) increase in birth weight (P=.001) and each maternal copy with a 30-g (95% CI 15-45 g) increase in offspring birth weight (P=2.8x10-5). Stratification by fetal genotype suggested that the association was driven by maternal genotype (31-g [95% CI 9-48 g] increase per allele; corrected P=.003). Analysis of diabetes-related traits in 10,314 nondiabetic individuals suggested the most likely mechanism is that the risk allele reduces maternal insulin secretion (disposition index reduced by ~0.15 standard deviation; P=1x10-4), which results in increased maternal glycemia in pregnancy and hence increased offspring birth weight. We combined information with the other common variant known to alter fetal growth, the -30G-->A polymorphism of glucokinase (rs1799884). The 4% of offspring born to mothers carrying three or four risk alleles were 119 g (95% CI 62-172 g) heavier than were the 32% born to mothers with none (for overall trend, P=2x10-7), comparable to the impact of maternal smoking during pregnancy. In conclusion, we have identified the first type 2 diabetes-susceptibility allele to be reproducibly associated with birth weight. Common gene variants can substantially influence normal birth-weight variation.

A common haplotype of the glucokinase gene alters fasting glucose and birth weight: association in six studies and population-genetics analyses

Fasting glucose is associated with future risk of type 2 diabetes and ischemic heart disease and is tightly regulated despite considerable variation in quantity, type, and timing of food intake. In pregnancy, maternal fasting glucose concentration is an important determinant of offspring birth weight. The key determinant of fasting glucose is the enzyme glucokinase (GCK). Rare mutations of GCK cause fasting hyperglycemia and alter birth weight. The extent to which common variation of GCK explains normal variation of fasting glucose and birth weight is not known. We aimed to comprehensively define the role of variation of GCK in determination of fasting glucose and birth weight, using a tagging SNP (tSNP) approach and studying 19,806 subjects from six population-based studies. Using 22 tSNPs, we showed that the variant rs1799884 is associated with fasting glucose at all ages in the normal population and exceeded genomewide levels of significance (P=10-9). rs3757840 was also highly significantly associated with fasting glucose (P=8x10-7), but haplotype analysis revealed that this is explained by linkage disequilibrium (r2=0.2) with rs1799884. A maternal A allele at rs1799884 was associated with a 32-g (95% confidence interval 11-53 g) increase in offspring birth weight (P=.002). Genetic variation influencing birth weight may have conferred a selective advantage in human populations. We performed extensive population-genetics analyses to look for evidence of recent positive natural selection on patterns of GCK variation. However, we found no strong signature of positive selection. In conclusion, a comprehensive analysis of common variation of the glucokinase gene shows that this is the first gene to be reproducibly associated with fasting glucose and fetal growth.

Maternal glucose levels influence birthweight and 'catch-up' and 'catch-down' growth in a large contemporary cohort

AIM

To explore the effects of maternal glucose on birthweight, infant and childhood growth in non-diabetic pregnant women using routinely collected data.

METHODS

Routinely collected data were extracted retrospectively from two clinical databases. These data comprised measurements of maternal random plasma glucose, infant birthweight, infant and child weight and height at 6-8 weeks, 24-36 weeks and 96-120 weeks in 6263 cases. After data cleaning, 4681 were analysed.

RESULTS

When the data were analysed in thirds, a positive association between birthweight standard deviation scores (SDS), weight SDS and height SDS with maternal random plasma glucose (RPG) was observed. Regression analysis of birthweight SDS and RPG was significant (P < 0.001). Babies were approximately 48 g heavier at birth for each 1 mmol/l increase of mother's RPG. Infants who showed 'catch-up' growth (as shown by change in weight SDS) at 2 years were born to mothers with lower glucose levels than infants who showed 'catch-down' growth (P < 0.001).

CONCLUSIONS

Random maternal glucose concentrations (taken at 28 weeks' gestation) in the normal range are positively related to birthweight. Glucose concentrations also predict greater weight and length in infancy. Despite this, babies born to mothers with higher glucose concentrations within the normal range show significant 'catch-down' growth in infancy as shown by a fall in weight SDS.

Anthropometry, glucose tolerance, and insulin concentrations in Indian children: relationships to maternal glucose and insulin concentrations during pregnancy

OBJECTIVE

The purpose of this study was to test the hypothesis that the environment experienced by fetuses of mothers with gestational diabetes mellitus (GDM) and mothers with higher glucose concentrations that are in the normal range causes increased adiposity and altered glucose/insulin metabolism in childhood.

RESEARCH DESIGN AND METHODS

Children (n = 630) whose mothers were tested for glucose tolerance during pregnancy had detailed anthropometry performed at birth and annually thereafter. At 5 years, plasma glucose and insulin concentrations were measured in the children (2-h oral glucose tolerance test) and their fathers (fasting samples only).

RESULTS

Newborns of diabetic mothers (n = 41) were larger in all body measurements than control newborns (babies with nondiabetic parents). At 1 year, these differences had diminished and were not statistically significant. At 5 years, female offspring of diabetic mothers had larger subscapular and triceps skinfold thicknesses (P = 0.01) and higher 30- and 120-min insulin concentrations (P < 0.05) than control children. Offspring of diabetic fathers (n = 41) were lighter at birth than control children (P < 0.001); they showed no differences in anthropometry at 5 years. In control children, skinfold thickness and 30-min insulin concentrations were positively related to maternal insulin area under the curve, and skinfold thicknesses were related to paternal fasting insulin concentrations independently of the parents' skinfold thickness and socioeconomic status.

CONCLUSIONS

Maternal GDM is associated with adiposity and higher glucose and insulin concentrations in female offspring at 5 years. The absence of similar associations in offspring of diabetic fathers suggests a programming effect in the diabetic intrauterine environment. More research is needed to determine whether higher maternal glucose concentrations in the nondiabetic range have similar effects.

Nutrition in multiple gestations

Multiple pregnancies represent a state of magnified nutritional requirements, resulting in a greater nutrient drain on maternal resources and an accelerated depletion of nutritional reserves. Maternal weight gain to 20 weeks and between 20 and 28 weeks has the greatest effect on birthweight in twin and triplet pregnancies, particularly among underweight women. Parity, which most likely represents a higher proportion of body fat, has a positive effect on pregnancy outcome, with an average 7 to 10 days longer gestation for multiparous versus nulliparous women. In addition to being the nutrients most often lacking in a woman's diet, calcium, magnesium, and zinc have been identified as having the most potential for reducing pregnancy complications and improving outcomes.

Glucose tolerance in pregnancy in South India: relationships to neonatal anthropometry

BACKGROUND

The incidence of type 2 diabetes is increasing worldwide, most rapidly in developing countries such as India. Exposure as a fetus to maternal gestational diabetes is thought to be a risk factor for developing the disease. This study was set up to determine the incidence of gestational diabetes mellitus in one urban maternity unit in South India and to examine its effect on the offspring's neonatal anthropometry, childhood growth, and glucose/insulin metabolism. This paper reports neonatal outcomes.

METHODS

Seven hundred and eighty five women were recruited consecutively from the antenatal clinic of the Holdsworth Memorial Hospital, Mysore and underwent a 100 g, 3-hr oral glucose tolerance test at 30 +/- 2 weeks gestation. Gestational diabetes was defined using Carpenter and Coustan criteria. The babies were measured in detail at birth.

RESULTS

Mean maternal age and body mass index were 23.6 years and 23.1 kg/m(2). The incidence of gestational diabetes was 6.2%. Mothers with gestational diabetes had babies that were heavier (3339 g compared with 2956 g for non-diabetic mothers) and larger in measurements of fat, muscle, and skeleton. Even in non-diabetic pregnancies, neonatal weight, head circumference, and ponderal index were positively related to maternal fasting glucose concentrations (P < or = 0.05 for all).

CONCLUSIONS

The incidence of gestational diabetes was high in this unselected sample of mothers booking into one urban Indian maternity unit. Community-based studies are required to confirm this. The effect of maternal glucose concentrations on neonatal anthropometry is continuous and extends into the "normal" glycemic range.

Ponderal index is a poor predictor of in utero growth retardation

OBJECTIVE

To evaluate the usefulness of ponderal index (PI) and related indices of weight and length in identifying asymmetric growth, body thinness and organ asymmetry associated with IUGR.

DESIGN

Cross sectional study.

SETTING

Aberdeen Maternity Hospital.

POPULATION

The population includes term (>/=37 weeks) singleton live births (n= 53,934) between 1986 and 1996, ultrasound measurements in 2522 pregnancies, 712 unselected term pregnancies in 1979/1980 and stillbirths (24-36 weeks) between 1986 and 1995 where the fetus was diagnosed as suffering from acute (n= 73) or chronic (n= 30) anoxic death.

METHODS

The strength of association between direct measures of IUGR and various indices of weight and length was determined by linear and multiple stepwise linear regression.

MAIN OUTCOME MEASURES

Weight, length, PI and skinfold thicknesses (triceps, biceps, flank thighs, back) were measured at birth. Abdominal circumference, biparietal diameter and femur length were measured by ultrasound at >/=37 weeks. Ratio of liver, heart and kidney to brain were measured in stillbirths.

RESULTS

Weight alone was a better predictor of skinfold thickness, abdominal circumference and the ratio of abdominal circumference to biparietal diameter than weight divided by length raised to the power 1, 2, 3 (PI), 4 or 5. The inclusion of gestational age made little difference to the predictive ability of weight for these full term births. Weight, but not PI, was significantly different between the two groups of stillborn fetuses (chronic and acute), which had significantly different (P < 0.001) organ ratios.

CONCLUSION

Body weight alone was a better predictor of anthropometric ratios, organ asymmetry and measures of thinness at birth thought to be associated with IUGR than the PI. The inclusion of a length term generally reduced the predictive ability with the highest powers resulting in the poorest prediction.

Dietary, evolutionary, and modernizing influences on the prevalence of type 2 diabetes

An evolutionary perspective is used to elucidate the etiology of the current epidemic of type 2 diabetes estimated at 151 million people. Our primate legacy, fossil hominid, and hunting-gathering lifestyles selected for adaptive metabolically thrifty genotypes and phenotypes are rendered deleterious through modern lifestyles that increase energy input and reduce output. The processes of modernization or globalization include the availability and abundance of calorically dense/low-fiber/high-glycemic foods and the adoption of sedentary Western lifestyles, leading to obesity among both children and adults in developed and developing countries. These trends are projected to continue for a number of decades.

Long-term risk of malignant neoplasm associated with gestational glucose intolerance

BACKGROUND

Previous studies have demonstrated an association between diabetes mellitus and cancer risk. However to the author's knowledge, no data regarding the risk of cancer associated with subclinical impaired glucose tolerance have been published to date. An association between various types of cancer and any continuum of risk across the spectrum of glucose tolerance may be important in determining the nature of the association between diabetes mellitus and the risk of malignancy.

METHODS

The current study was conducted to examine the long-term risk of malignant neoplasms associated with maternal glucose intolerance. A 20-year follow-up study of a cohort of women who had previously taken part in a study in 1980 that investigated maternal glucose metabolism and fetal outcome was performed. Gestational glucose metabolism, smoking behavior, and weight and height measured at the time of index pregnancy, as well as weight, height, and smoking behavior assessed by questionnaire in 1999, were examined. The main endpoint of the study was hospital admission with a diagnosis of malignant neoplasm as ascertained by linkage data.

RESULTS

Thirty-four of the 753 women living in Grampian (4.5%) were admitted to the hospital with a diagnosis of malignant neoplasm; of these, 18 cases were malignant neoplasms of the breast. After adjustment for known risk factors, both malignant neoplasm and malignant neoplasm of the breast were found to be significantly associated with gestational glucose intolerance.

CONCLUSIONS

Subclinical glucose intolerance during pregnancy was found to be associated with a dose-related increase in the risk of malignant neoplasm, particularly malignant neoplasm of the breast.

Higher weight at birth is related to decreased maternal amino acid oxidation during pregnancy

BACKGROUND

Small size at birth is associated with cardiovascular disease in adult life. Decreased fetal growth may result from a limitation in the nutrient supply to the fetus. Net tissue deposition in the mother and fetus increases the demand for nitrogen, but because maternal consumption of protein does not increase, there must be a change in the partitioning of amino acids, away from oxidation and toward deposition.

OBJECTIVE

Our objective was to characterize amino acid oxidation in pregnancy and to investigate whether the relative partitioning of amino acids was related to fetal growth.

DESIGN

We determined amino acid oxidation as urea production in 25 women during mid (17-19 wk) and late (26-29 wk) gestation. Urea production was measured from urinary [(15)N-(15)N]urea excretion over 48 h after a single oral dose of [(15)N-(15)N]urea. We measured the infant's size at birth.

RESULTS

For the group as a whole, urea excretion decreased and amino acid oxidation remained similar between mid and late pregnancy, but there was wide variation between the women. Heavier infants were born to the mothers in whom amino acid oxidation decreased the most during pregnancy (slope of regression line: -80 g x g N(-1) x d(-1); 95% CI: -129, -31; P = 0.003). After adjustment for length of gestation and the infant's sex, the change in maternal amino acid oxidation explained 34% of the variation in birth weight.

CONCLUSIONS

Amino acid oxidation varied widely between the women during pregnancy. Understanding the ability of a pregnant woman to adapt metabolically may have implications for establishing dietary recommendations in pregnancy.

Protein, amino acid and nitrogen metabolism during pregnancy: how might the mother meet the needs of her fetus?

During pregnancy there is an increased demand for energy and protein to enable the fetus and placenta to grow. Current recommendations suggest an allowance for pregnancy of 6-10 g protein per day, however there is little consistent evidence that this is needed. Furthermore, there does not appear to be a simple relationship between the dietary protein intake of the mother and the size of the baby. If protein needs to be conserved, pregnant women must adapt metabolically. Methods for measuring protein metabolism have varied between studies. Some isotopic approaches are relatively invasive, but noninvasive methods are also available which can be used in larger numbers of women in free-living conditions. Taken together, isotopic studies during pregnancy indicate that there is a shift in the partitioning of amino acids towards net tissue deposition, reflected in an increased rate of protein synthesis, and away from oxidation, reflected in measures of urea synthesis. An understanding of the influences on fetal growth is needed to enable us to deal with the major problems in public health of our time. There is substantial evidence that impaired growth and development in utero is associated with a higher risk of cardiovascular and metabolic disease in adult life. In order to establish what dietary recommendations should be made, we need to explore further how women cope metabolically with the demands of pregnancy, particularly when faced with unusual demands over and above pregnancy, such as infection.

Maternal glucose concentration influences fetal growth, gestation, and pregnancy complications

Using 1990-1995 data, the authors examined the influence of post-challenge maternal glucose concentration on pregnancy outcome in 1,157 nondiabetic US gravidas. After control for potential confounding variables and comparing gravidas with lower glucose concentrations (<99 mg/dl) with the others, they found that mean birth weight increased by 50 g and 200 g with glucose concentrations of 99-130 mg/dl and >130 mg/dl, respectively. Increased maternal glucose concentration also was associated with an increased risk of large-for-gestation fetuses (p for trend < 0.001) and a decreased risk of fetal growth restriction (p for trend < 0.05). The association between glucose and gestation was inverse and significantly shortened when glucose concentrations were higher. Maternal complications increased twofold or more with high glucose concentrations and included cesarean section and clinical chorioamnionitis. Chorioamnionitis in combination with high maternal glucose concentration increased the risk of very preterm delivery almost 12-fold. These observations extend Pedersen's hypothesis-that high concentrations of maternal glucose give rise to increased nutrient transfer to the fetus and increase fetal growth, beyond the model of maternal diabetes (Acta Endocrinol 1954;16:330-42). They raise the question of whether higher, but seemingly normal maternal glucose concentration predisposes to or is a marker for placental inflammation and infection.

Fetal programming and adult health

Low birthweight is now known to be associated with increased rates of coronary heart disease and the related disorders stroke, hypertension and non-insulin dependent diabetes. These associations have been extensively replicated in studies in different countries and are not the result of confounding variables. They extend across the normal range of birthweight and depend on lower birthweights in relation to the duration of gestation rather than the effects of premature birth. The associations are thought to be consequences of 'programming', whereby a stimulus or insult at a critical, sensitive period of early life has permanent effects on structure, physiology and metabolism. Programming of the fetus may result from adaptations invoked when the materno-placental nutrient supply fails to match the fetal nutrient demand. Although the influences that impair fetal development and programme adult cardiovascular disease remain to be defined, there are strong pointers to the importance of maternal body composition and dietary balance during pregnancy.

Diabetes in adolescent patients: diagnostic dilemmas

The classification of diabetes mellitus by types (1 or 2), or by age of onset (juvenile or adult), helps to clarify many aspects of pathophysiology, prognosis, and therapy. However, less-commonly encountered patients, presenting in childhood or adolescence, may not fit neatly into one or the other group. These include teenagers who present with new-onset diabetes with ketoacidosis, but who are later able to be managed permanently as type 2 patients. Other adolescent patients present with only minimal glucose intolerance, then proceed to develop type 1 diabetes, with evidence of autoimmune etiology, after a variable number of years. Four patients are presented to illustrate these diagnostic dilemmas.

The role of genetic susceptibility in the association of low birth weight with type 2 diabetes

We suggest that altered fetal growth and type 2 diabetes may be two phenotypes of the same genotype - in other words the 'thrifty phenotype' is the result of a 'thrifty genotype'. Supporting this there is strong evidence that paternal factors and, therefore, genes influence fetal growth and that these paternal genes affecting fetal growth may also alter diabetes risk. Further study is needed to determine whether common gene variants can explain the association between reduced birth weight and increased risk of type 2 diabetes. If the genetic hypothesis is true, common diabetes genes are likely to have subtle effects on insulin secretion and/or action and, therefore, subtle effects on fetal growth. Large cohorts of infants and their parents will be required - probably in the region of thousands rather than hundreds - to identify gene variants that may explain the association between reduced birth weight and increased risk of type 2 diabetes. All previously described associations between birth weight and type 2 diabetes have required many hundreds of subjects and it is likely that the geneticists and the 'programmists' are trying to identify very subtle physiological effects.

The fetal insulin hypothesis: an alternative explanation of the association of low birthweight with diabetes and vascular disease

Low birthweight is associated with insulin resistance, hypertension, coronary-artery disease, and non-insulin-dependent diabetes (NIDDM). A suggested explanation for this association is intrauterine programming in response to maternal malnutrition. We propose, however, that genetically determined insulin resistance results in impaired insulin-mediated growth in the fetus as well as insulin resistance in adult life. Low birthweight, measures of insulin resistance in life, and ultimately glucose intolerance, diabetes, and hypertension could all be phenotypes of the same insulin-resistant genotype. There is evidence to support this hypothesis. Insulin secreted by the fetal pancreas in response to maternal glucose concentrations is a key growth factor. Monogenic diseases that impair sensing of glucose, lower insulin secretion, or increase insulin resistance are associated with impaired fetal growth. Polygenic influences resulting in insulin resistance in the normal population are therefore likely to result in lower birthweight. Abnormal vascular development during fetal life and early childhood, as a result of genetic insulin resistance, could also explain the increased risk of hypertension and vascular disease. The predisposition to NIDDM and vascular disease is likely to be the result of both genetic and fetal environmental factors.

Inter-relationship between serum concentrations of glucose, glucagon and insulin during the first two days of life in healthy newborns

The relationship between serum concentrations of glucose, insulin and glucagon during the first two days of life was studied in healthy newborns. The first capillary blood sample was obtained at 3-15 h of age (median 6 h; day 0) and a second sample approximately 24 h later (day 1). Serum glucose concentrations in the first sample averaged 2.1 +/- 0.07 mmol/l (mean +/- SEM; n = 60) and were positively correlated with postnatal age (p < 0.01). Serum glucagon concentrations in the first sample averaged 570 +/- 32 pg/ml and were inversely correlated with glucose concentrations (p < 0.0001). At the second sampling, serum glucose concentrations had increased to 2.9 +/- 0.07 mmol/l (p < 0.001; n = 57) and serum glucagon concentrations had decreased to 403 +/- 22 pg/ml (p < 0.001). Serum insulin concentrations were 11.7 +/- 0.3 microU/ml and 10.2 +/- 0.3 microU/ml at the two samplings and did not correlate with serum glucose concentrations. The relationship of serum glucose and hormone concentrations to maternal and infant characteristics was studied by stepwise regression analysis. Serum glucose concentration on day 0 was positively correlated with postnatal age (p < 0.01) and birth weight (p < 0.05) but inversely correlated with duration of labour (p < 0.05). Serum glucose concentration on day 1 was positively correlated with birth weight (p < 0.0001) and inversely correlated with maternal prep-pregnancy weight (p < 0.05). Similar analyses of serum hormone concentrations did not demonstrate any relationships with maternal or infant characteristics.(ABSTRACT TRUNCATED AT 250 WORDS)

Relation of birthweight to maternal plasma glucose and insulin concentrations during normal pregnancy

Maternal diabetes mellitus is complicated by fetal macrosomia and predisposes the offspring to diabetes, but recent evidence indicates that a low, not high, birthweight is associated with a higher incidence of Type 2 (non-insulin dependent) diabetes in adult life. To clarify the relationships between maternal glucose and insulin levels and birthweight, we measured oral glucose tolerance and neonatal weight in a large group (n = 529) of women during the 26th week of pregnancy. Women with gestational diabetes (n = 17) had more familial diabetes, higher pre-pregnancy body weight, and tended to have large-for-gestational-age babies. In contrast, women with essential hypertension (n = 10) gave birth to significantly (p < 0.01) smaller babies. In the normal group (without gestational diabetes or hypertension, n = 503), maternal body weight before pregnancy and at term, maternal height, week of delivery, gender of the newborn, and parity were all significant, independent predictors of birthweight, together explaining 23% of the variability of neonatal weight. In addition, both fasting (p < 0.006) and 2-h post-glucose (p = 0.03) maternal plasma glucose concentrations were positively associated with birthweight independent of the other physiological determinants, accounting, however, for only 10% of the explained variability. In a subgroup of 134 normal mothers with pre-pregnancy body mass index of less than 25 kg.m-2, in whom plasma insulin measurements were available, the insulin area-under-curve was inversely related to birthweight (p < 0.02) after simultaneously adjusting for physiological factors and glucose area.(ABSTRACT TRUNCATED AT 250 WORDS)

The ranges of insulin response and glucose tolerance in lean, normal, and obese women during pregnancy

OBJECTIVE

We characterized insulin secretion and glucose disposal in a large unselected group of women, encompassing the full spectrum of glucose tolerance in pregnancy, and related the findings to maternal obesity.

STUDY DESIGN

Intravenous glucose tolerance and first-phase insulin response were measured at about 32 weeks' gestation in 690 unselected pregnancies. The women were designated as "lean," "normal," or "obese" on weight-for-height criteria.

RESULTS

The distribution of insulin response was bimodal, but there was no corresponding dichotomy in maternal glucose disposal rate. Insulin response was greatest and glucose disposal rate slowest in obese women. In general, "poor" glucose tolerance was associated with relatively low insulin output. It was not possible to identify any cluster of women, obese or otherwise, in whom poor glucose tolerance was specifically associated with an unusually high insulin response.

CONCLUSION

The data indicate that the distribution of glucose tolerance in pregnancy is a continuum. Glucose intolerance represents one end of that spectrum and is attributable to insufficient insulin secretion. This relative insufficiency is most frequent with maternal obesity.

Maternal postprandial glucose levels and infant birth weight: the Diabetes in Early Pregnancy Study. The National Institute of Child Health and Human Development--Diabetes in Early Pregnancy Study

The cause of macrosomia in the infant of the diabetic woman is still not completely defined. The National Institute of Child Health and Human Development--Diabetes in Early Pregnancy Study, which recruited insulin-dependent diabetic and control women before conception, provided an opportunity to address the relationship between maternal glycemia and percentile birth weight. Data were analyzed from 323 diabetic and 361 control women. Fasting and nonfasting venous plasma glucose were measured on alternate weeks in the first trimester and monthly thereafter. Glycosylated hemoglobin was measured weekly in the first trimester and monthly thereafter. More infants of the diabetic women were at or above the 90th percentile for birth weight than infants of control women (28.5% versus 13.1%, p less than 0.001). Although first-trimester nonfasting glucose and glycosylated hemoglobin levels were positively correlated with infant birth weight (p less than 0.001 and p = 0.008), when the analyses were adjusted for the variables of the subsequent trimesters the values became insignificant, whereas the third-trimester nonfasting glucose levels adjusted for values in prior trimesters emerged as the stronger predictor of percentile birth weight (p = 0.001). After adjusting for maternal hypertension, smoking, and ponderal index, the above relationships remained. In conclusion, monitoring of nonfasting glucose levels rather than the fasting levels, which are more commonly monitored in clinical practice, are necessary to prevent macrosomia.

Persistent tardive dyskinesia and neuroleptic effects on glucose tolerance

The relations of persistent tardive dyskinesia (TD) to glucose tolerance and family history of type 2 diabetes mellitus (FH-NIDDM) were examined in 22 schizophrenic patients. All patients underwent a standard oral glucose tolerance test (GTT) while receiving haloperidol, and 15 patients also underwent a GTT when drug free. Fasting blood glucose (FBS) was significantly higher in the TD group than in the non-TD group in the medicated condition, but not in the drug-free state. TD and non-TD groups did not differ significantly in postload glucose levels either in the drug-free or in the medicated condition. However, relative to the drug-free state, haloperidol-treated TD patients showed decreased glucose tolerance while non-TD patients showed increased glucose tolerance. Seven (32%) of the 22 patients had an FH-NIDDM. A positive FH-NIDDM was significantly associated with the presence of TD and with higher drug-free FBS. A possible role of melatonin in mediating the TD-augmenting effects of FH-NIDDM and the neuroleptic-induced decrease in glucose tolerance has been proposed.