The association between maternal dietary micronutrient intake and neonatal anthropometry - secondary analysis from the ROLO study.

BACKGROUND: Micronutrients are necessary for fetal growth. However increasingly pregnant women are nutritionally replete and little is known about the effect of maternal micronutrient intakes on fetal adiposity in mothers with increased BMI. The aim of this study was to examine the association of maternal dietary micronutrient intake with neonatal size and adiposity in a cohort at risk of macrosomia. METHODS: This was a cohort analysis of 554 infants from the ROLO study. Three day food diaries from each trimester were collected. Neonatal weight, length, circumferences and skinfold thicknesses were measured at birth. Multiple linear regression was used to identify associations between micronutrient intakes and neonatal anthropometry. RESULTS: Birthweight was negatively associated with maternal trimester 3 vitamin D intake and positively associated with trimester 3 vitamin B12 intake R2adj 19.8% (F = 13.19, p <0.001). Birth length was positively associated with trimester 3 magnesium intake R2adj 12.9% (F = 8.06, p <0.001). In terms of neonatal central adiposity; abdominal circumference was positively associated with maternal trimester 3 retinol intake and negatively associated with trimester 3 vitamin E and selenium intake R2adj 11.9% (F = 2.93, p = 0.002), waist:length ratio was negatively associated with trimester 3 magnesium intake R2adj 20.1% (F = 3.92, p <0.001) and subscapular:triceps skinfold ratio was negatively associated with trimester 1 selenium intake R2adj7.2% (F = 2.00, p = 0.047). CONCLUSIONS: Maternal micronutrient intake was associated with neonatal anthropometry even in women not at risk of malnutrition. Further research is necessary to determine optimal micronutrient intake in overweight and obese pregnant women. TRIAL REGISTRATION: Current Controlled Trials ISRCTN54392969.

Maternal low glycaemic index diet, fat intake and postprandial glucose influences neonatal adiposity--secondary analysis from the ROLO study.

BACKGROUND: The in utero environment is known to affect fetal development however many of the mechanisms by which this occurs remain unknown. The aim of this study was to examine the association between maternal dietary macronutrient intake and lifestyle throughout pregnancy and neonatal weight and adiposity. METHODS: This was an analysis of 542 mother and infant pairs from the ROLO study (Randomised cOntrol trial of LOw glycaemic index diet versus no dietary intervention to prevent recurrence of fetal macrosomia). Food diaries as well as food frequency and lifestyle and physical activity questionnaires were completed during pregnancy. Maternal anthropometry was measured throughout pregnancy and neonatal anthropometry was measured at birth. RESULTS: Multiple linear regression analysis revealed the main maternal factor associated with increased birth weight was greater gestational weight gain R2adj 23.3% (F = 11.547, p < 0.001). The main maternal factor associated with increased birth length was non-smoking status R2adj 27.8% (F = 6.193, p < 0.001). Neonatal central adiposity (determined using waist:length ratio) was negatively associated with maternal age, and positively associated with the following parameters: smoking status, maternal pre-pregnancy arm circumference, percentage energy from saturated fat in late pregnancy, postprandial glucose at 28 weeks gestation and membership of the control group with a positive trend towards association with trimester 2 glycaemic load R2adj 38.1% (F = 8.000, p < 0.001). CONCLUSIONS: Several maternal diet and lifestyle factors were associated with neonatal anthropometry . Low glycaemic index dietary intervention in pregnancy was found to have a beneficial effect on neonatal central adiposity. Additionally, central adiposity was positively associated with maternal dietary fat intake and postprandial glucose highlighting the important role of healthy diet in pregnancy in promoting normal neonatal adiposity. TRIAL REGISTRATION: Current Controlled Trials ISRCTN54392969.

The association between TNF-α and insulin resistance in euglycemic women.

Chronic low levels of inflammation have links to obesity, diabetes and insulin resistance. We sought to assess the relationship between cytokine tumor necrosis factor (TNF-α) and insulin resistance in a healthy, euglycemic population. This is a prospective study of 574 non-diabetic mother and infant pairs. Maternal body mass index (BMI), TNF-α, glucose and insulin were measured in early pregnancy and at 28 weeks. Insulin resistance was calculated by HOMA index. At delivery birthweight was recorded and cord blood analysed for fetal C-peptide and TNF-α. In a multivariate model, maternal TNF-α in early pregnancy was predicted by maternal insulin resistance at the same time-point, (ß=0.54, p<0.01), and maternal TNF-α at 28 weeks was predicted by maternal insulin resistance in early pregnancy (ß=0.24, p<0.01) and at 28 weeks (ß=0.39, p<0.01). These results, in a large cohort of healthy, non-diabetic women have shown that insulin resistance, even at levels below those diagnostic of gestational diabetes, is associated with maternal and fetal inflammatory response. These findings have important implications for defining the pathways of fetal programming of later metabolic syndrome and childhood obesity.

The influence of a low glycemic index dietary intervention on maternal dietary intake, glycemic index and gestational weight gain during pregnancy: a randomized controlled trial.

BACKGROUND: Maternal diet is known to impact pregnancy outcome. Following a low glycemic index (GI) diet during pregnancy has been shown to improve maternal glycemia and reduce infant birthweight and may be associated with a higher fibre intake. We assessed the impact of a low GI dietary intervention on maternal GI, nutritional intake and gestational weight gain (GWG) during pregnancy. Compliance and acceptability of the low GI diet was also examined. METHOD: Eight hundred women were randomised in early pregnancy to receive low GI and healthy eating dietary advice or to receive standard maternity care. The intervention group received dietary advice at a group education session before 22 weeks gestation. All women completed a 3 day food diary during each trimester of pregnancy. Two hundred and thirty five women from the intervention arm and 285 women from the control arm returned complete 3x3d FDs and were included in the present analysis. RESULTS: Maternal GI was significantly reduced in the intervention group at trimester 2 and 3. The numbers of women within the lowest quartile of GI increased from 37% in trimester 1 to 52% in trimester 3 (P < 0.001) among the intervention group. The intervention group had significantly lower energy intake (P < 0.05), higher protein (% TE) (P < 0.01) and higher dietary fibre intake (P < 0.01) post intervention. Consumption of food groups with known high GI values were significantly reduced among the intervention group. Women in the intervention low GI group were less likely to exceed the Institute of Medicine's GWG goals. CONCLUSION: A dietary intervention in early pregnancy had a positive influence on maternal GI, food and nutrient intakes and GWG. Following a low GI diet may be particularly beneficial for women at risk of exceeding the GWG goals for pregnancy.

Maternal dietary patterns and associated nutrient intakes during each trimester of pregnancy.

OBJECTIVE: To determine the main dietary patterns of pregnant women during each of the three trimesters of pregnancy and to examine associated nutrient intakes. DESIGN: Participants completed a 3 d food diary during each trimester of pregnancy. Thirty-six food groups were created and dietary patterns were derived using k-means cluster analysis. SETTING: National Maternity Hospital, Dublin, Ireland. SUBJECTS: Two hundred and eighty-five healthy pregnant women aged between 20 and 41 years. RESULTS: Two dietary patterns were identified at each time point. They were labelled 'Unhealthy' (n =143, 150 and 155 at trimester 1, 2 and 3, respectively) and 'Health Conscious' (n 142, 135 and 130 at trimester 1, 2 and 3, respectively). Women in the 'Health Conscious' cluster were significantly older, had lower BMI and were higher educated than those in the 'Unhealthy' cluster. Of those in the 'Unhealthy' cluster in the first trimester (n =143), 103 (72.0 %) continued in this dietary pattern into trimester 2 and eighty-one (56.6 %) continued into trimester 3. Of those in the 'Health Conscious' cluster in trimester 1 (n =142), ninety-five (66.9 %) continued in this dietary pattern into trimester 2 and sixty-nine (48.6 %) continued into trimester 3. CONCLUSIONS: Cluster analysis produced two clearly defined dietary patterns at each stage of pregnancy. Knowledge of maternal dietary patterns is important for the development of pregnancy-specific dietary guidelines. Identifying women with an 'Unhealthy' dietary pattern in early pregnancy affords the opportunity for a dietary intervention which may positively impact both maternal and infant health.

Methodology for adding and amending glycaemic index values to a nutrition analysis package.

Since its introduction in 1981, the glycaemic index (GI) has been a useful tool for classifying the glycaemic effects of carbohydrate foods. Consumption of a low-GI diet has been associated with a reduced risk of developing CVD, diabetes mellitus and certain cancers. WISP (Tinuviel Software, Llanfechell, Anglesey, UK) is a nutrition software package used for the analysis of food intake records and 24 h recalls. Within its database, WISP contains the GI values of foods based on the International Tables 2002. The aim of the present study is to describe in detail a methodology for adding and amending GI values to the WISP database in a clinical or research setting, using data from the updated International Tables 2008.

The influence of maternal glycaemia and dietary glycaemic index on pregnancy outcome in healthy mothers.

Infant birth weight has increased in Ireland in recent years along with levels of childhood overweight and obesity. The present article reviews the current literature on maternal glycaemia and the role of the dietary glycaemic index (GI) and its impact on pregnancy outcomes. It is known that maternal weight and weight gain significantly influence infant birth weight. Fetal macrosomia (birth weight >4000 g) is associated with an increased risk of perinatal trauma to both mother and infant. Furthermore, macrosomic infants have greater risk of being obese in childhood, adolescence and adulthood compared to normal-sized infants. There is evidence that there is a direct relationship between maternal blood glucose levels during pregnancy and fetal growth and size at birth, even when maternal blood glucose levels are within their normal range. Thus, maintaining blood glucose concentrations within normal parameters during pregnancy may reduce the incidence of fetal macrosomia. Maternal diet, and particularly its carbohydrate (CHO) type and content, influences maternal blood glucose concentrations. However, different CHO foods produce different glycaemic responses. The GI was conceived by Jenkins in 1981 as a method for assessing the glycaemic responses of different CHO. Data from clinical studies in healthy pregnant women have documented that consuming a low-GI diet during pregnancy reduces peaks in postprandial glucose levels and normalises infant birth weight. Pregnancy is a physiological condition where the GI may be of particular relevance as glucose is the primary fuel for fetal growth.

Maternal Nutrition and Glycaemic Index during Pregnancy Impacts on Offspring Adiposity at 6 Months of Age--Analysis from the ROLO Randomised Controlled Trial.

Childhood obesity is associated with increased risk of adult obesity and metabolic disease. Diet and lifestyle in pregnancy influence fetal programming; however the influence of specific dietary components, including low glycaemic index (GI), remains complex. We examined the effect of a maternal low GI dietary intervention on offspring adiposity at 6 months and explored the association between diet and lifestyle factors in pregnancy and infant body composition at 6 months. 280 6-month old infant and mother pairs from the control (n = 142) and intervention group (n = 138), who received low GI dietary advice in pregnancy, in the ROLO study were analysed. Questionnaires (food diaries and lifestyle) were completed during pregnancy, followed by maternal lifestyle and infant feeding questionnaires at 6 months postpartum. Maternal anthropometry was measured throughout pregnancy and at 6 months post-delivery, along with infant anthropometry. No difference was found in 6 months infant adiposity between control and intervention groups. Maternal trimester three GI, trimester two saturated fats and trimester one and three sodium intake were positively associated with offspring adiposity, while trimester two and three vitamin C intake was negatively associated. In conclusion associations were observed between maternal dietary intake and GI during pregnancy and offspring adiposity at 6 months of age.

The association between maternal nutrition and lifestyle during pregnancy and 2-year-old offspring adiposity: analysis from the ROLO study.

AIM: To examine the association between maternal nutrition and lifestyle factors and offspring adiposity, using baseline and 2-year postpartum follow-up data from a randomised control trial of low glycaemic index diet. SUBJECT AND METHODS: Food diaries and lifestyle questionnaires were completed during pregnancy and infant feeding and maternal lifestyle questionnaires 2 years postpartum for 281 mother and infant pairs from the ROLO study. Maternal anthropometry was measured throughout pregnancy and infant and maternal anthropometry was measured 2 years postpartum. RESULTS: Maternal 2 year postpartum body mass index (BMI) was positively associated with offspring BMI-for-age z-score (B = 0.105, p = 0.015). Trimester 2 saturated fat intake was positively associated with offspring subscapular:triceps skinfold ratio (B = 0.018, p = 0.001). Trimester 1 glycaemic index was also positively associated with offspring sum of subscapular and triceps skinfolds (B = 0.009, p = 0.029). CONCLUSIONS: Maternal BMI 2 years postpartum was positively associated with offspring BMI. Pregnancy saturated fat intake was positively and polyunsaturated fat negatively associated with offspring adiposity. While further research is necessary, pregnancy and the postpartum period may be early opportunities to combat childhood obesity.

Maternal diet and weight at 3 months postpartum following a pregnancy intervention with a low glycaemic index diet: results from the ROLO randomised control trial.

UNLABELLED: Pregnancy increases the risk of being overweight at a later time period, particularly when there is excessive gestational weight gain. There remains a paucity of data into the effect of low glycaemic index (GI) pregnancy interventions postpartum. AIM: To examine the impact of a low glycaemic index diet during pregnancy on maternal diet 3 months postpartum. METHODOLOGY: This analysis examined the diet, weight and lifestyle of 460 participants of the ROLO study 3 months postpartum. Questionnaires on weight, physical activity, breastfeeding, supplement use, food label reading and dietary habits were completed. RESULTS: The intervention group had significantly greater weight loss from pre-pregnancy to 3 months postpartum than the control group (1.3 vs. 0.1 kg, p = 0.022). The intervention group reported greater numbers following a low glycaemic index diet (p < 0.001) and reading food labels (p = 0.032) and had a lower glycaemic load (GL) (128 vs. 145, p = 0.014) but not GI (55 vs. 55, p = 0.809) than controls. CONCLUSIONS: Low GI dietary interventions in pregnancy result in improved health-behaviours and continued reported compliance at 3 months postpartum possibly through lower dietary GL as a result of portion control. Greater levels of weight loss from pre-pregnancy to 3 months postpartum in the intervention group may have important positive implications for overweight and obesity.

Obstetric and metabolic implications of excessive gestational weight gain in pregnancy.

OBJECTIVE: To compare maternal characteristics, obstetric outcomes and insulin resistance in a cohort of women subdivided into those who did and those who did not exceed the Institute of Medicine (IOM) gestational weight gain guidelines. METHODS: This is a prospective study of 621 women without diabetes. Concentrations of glucose, insulin and leptin were measured in early pregnancy and at 28 weeks. Ultrasound at 34 weeks assessed fetal anthropometry including abdominal wall width (AAW). At delivery birthweight was recorded and fetal glucose, C-peptide and leptin measured in cord blood. Insulin resistance was calculated using the HOMA equation. Outcomes in those who did and did not exceed IOM guidelines were compared. RESULTS: Overall, 267 women (43%) exceeded IOM guidelines and 354 (57%) did not. On 34-week ultrasound women with excessive weight gain had higher fetal weights (2681 ± 356 g vs. 2574 ± 331, P = 0.001) and fetal adiposity (AAW) (5.29 ± 1.3 vs. 4.8 ± 1.2, P = 0.001). Infant birthweight and birthweight centiles were also higher in those who exceeded the guidelines. There was no difference between the two groups in maternal insulin resistance in early pregnancy, but by 28 weeks those with excessive weight gain had higher maternal HOMA indices and higher maternal leptin concentrations. CONCLUSION: Excessive maternal gestational weight gain has significant implications for infant growth and adiposity, with potential implications for later adult health.

The relationship between maternal and fetal vitamin D, insulin resistance, and fetal growth.

Evidence for a role of vitamin D in maintaining normal glucose homeostasis is inconclusive. We sought to clarify the relationship between maternal and fetal insulin resistance and vitamin D status. This is a prospective cohort study of 60 caucasian pregnant women. Concentrations of 25-hydroxyvitamin D (25-OHD), glucose, insulin, and leptin were measured in early pregnancy and at 28 weeks. Ultrasound at 34 weeks assessed fetal anthropometry including abdominal wall width, a marker of fetal adiposity. At delivery birth weight was recorded and fetal 25-OHD, glucose, C-peptide, and leptin measured in cord blood. Insulin resistance was calculated using the Homeostasis Model Assessment (HOMA) equation. We found that those with lower 25-OHD in early pregnancy had higher HOMA indices at 28 weeks, (r = -.32, P = .02). No significant relationship existed between maternal or fetal leptin and 25-OHD, or between maternal or fetal 25-OHD and fetal anthropometry or birth weight. The incidence of vitamin D deficiency was high at each time point (15%-45%). These findings lend support to routine antenatal supplementation with vitamin D in at risk populations.

Pregnancy in dark winters: implications for fetal bone growth?

OBJECTIVE: To prospectively examine the prevalence of hypovitaminosis D in pregnancy and to correlate maternal and fetal vitamin D to fetal anthropometry. DESIGN: A prospective cohort study. SETTING: Tertiary referral maternity hospital. PATIENT(S): Sixty pregnant women. INTERVENTION(S): Serum 25-hydroxyvitamin D (25OHD) was measured in early pregnancy, at 28 weeks, and in cord blood at delivery. MAIN OUTCOME MEASURE(S): The prevalence of hypovitaminosis D and the relationship between fetal growth and serum 25OHD concentrations. RESULT(S): Two subgroups were analyzed to examine results in the context of seasonal variation in 25OHD: a winter and a summer cohort. Fetal anthropometry was assessed at 20 and 34 weeks, and at delivery the neonatal anthropometry was recorded. There was a high prevalence of hypovitaminosis D ranging from 33% to 97%, with a marked seasonal variation. Fetal 25OHD concentrations correlated with all biometry at 20 weeks. In the winter cohort, a correlation was found between early pregnancy 25OHD and femur length at 20 weeks, and between 28-week 25OHD and femur length at 34 weeks. Infant length was shorter in those with early pregnancy 25OHD less than the median (52.1 vs. 53.6 cm). CONCLUSION(S): The high prevalence of maternal hypovitaminosis D during winter months in northern latitudes may have detrimental effects on fetal skeletal growth.

Low glycaemic index diet in pregnancy to prevent macrosomia (ROLO study): randomised control trial.

OBJECTIVE: To determine if a low glycaemic index diet in pregnancy could reduce the incidence of macrosomia in an at risk group. DESIGN: Randomised controlled trial. SETTING: Maternity hospital in Dublin, Ireland. PARTICIPANTS: 800 women without diabetes, all in their second pregnancy between January 2007 to January 2011, having previously delivered an infant weighing greater than 4 kg. INTERVENTION: Women were randomised to receive no dietary intervention or start on a low glycaemic index diet from early pregnancy. MAIN OUTCOMES: The primary outcome measure was difference in birth weight. The secondary outcome measure was difference in gestational weight gain. RESULTS: No significant difference was seen between the two groups in absolute birth weight, birthweight centile, or ponderal index. Significantly less gestational weight gain occurred in women in the intervention arm (12.2 v 13.7 kg; mean difference -1.3, 95% confidence interval -2.4 to -0.2; P=0.01). The rate of glucose intolerance was also lower in the intervention arm: 21% (67/320) compared with 28% (100/352) of controls had a fasting glucose of 5.1 mmol/L or greater or a 1 hour glucose challenge test result of greater than 7.8 mmol/L (P=0.02). CONCLUSION: A low glycaemic index diet in pregnancy did not reduce the incidence of large for gestational age infants in a group at risk of fetal macrosomia. It did, however, have a significant positive effect on gestational weight gain and maternal glucose intolerance. TRIAL REGISTRATION: Current Controlled Trials ISRCTN54392969.