Gestational Diabetes Independently Increases Birth Length and Augments the Effects of Maternal BMI on Birth Weight: A Retrospective Cohort Study

The associations of ferritin, serum lipid and plasma glucose levels across pregnancy in women with gestational diabetes mellitus and newborn birth weight

BACKGROUND

Women with gestational diabetes mellitus (GDM) are at greater risk of abnormal birth weight. Since the level of biochemical indicators could often affect the intrauterine growth and development of the fetus, it is of great practical significance to understand the changes of biochemical levels across pregnancy in women with GDM and to find out the indicators that play an important role in predicting birth weight.

METHODS

The data source of this study was from the Xi'an Longitudinal Mother-Child Cohort study (XAMC), in which women with GDM with normal and high pre-pregnancy body mass index (BMI) and their newborns between January 1^st and March 31^st in 2018 were included. The data of ferritin, serum lipid profile and fasting plasma glucose (FPG) of mothers in the three trimesters of pregnancy, as well as birth weight of newborns were all collected from medical records. Multiple linear regression and multivariate logistic regression analyses were used to explore the association of the biochemical indexes and birth weight. A P value < 0.05 was considered statistically significant.

RESULTS

A total of 782 mother-infant pairs were finally included and divided into normal weight group (NG) (n = 530, 67.8%) and overweight/obesity group (OG) (n = 252, 32.2%) according to maternal pre-pregnancy BMI. The level of ferritin in both NG and OG decreased during pregnancy (P for trend < 0.001 for all), whereas the levels of total cholesterol (TC), high density cholesterol (HDL-C), low density cholesterol (LDL-C) and triglycerides (TG) all showed an upward trend (P for trend < 0.05 for all). The levels of FPG in the two groups remained in a relatively stable during the whole pregnancy even though it was higher in OG during the 2^nd and 3^rd trimesters, whilst HbAlc levels in NG women increased (P for trend = 0.043) during pregnancy. Meanwhile, the risk of macrosomia and large-for-gestational-age (LGA) increased with the increase of FPG level (P for trend < 0.05). Multivariate logistic regression analyses results showed that only FPG level in the 3^rd trimester was correlated with birth weight, with birth weight increased by 44.9 g for each SD increase in FPG level.

CONCLUSION

Maternal FPG in the 3^rd trimester is an independent predictor of newborn birth weight, and a higher level of that is associated with an increased risk of macrosomia and LGA.

The Association Between Birth Weight and Fat, Sugar, and Vegetable Consumption in a National Sample of U.S. Preschool Age Children

INTRODUCTION

Adverse prenatal development is a contributor to obesity susceptibility in children. Dietary behavior is one mechanism through which adverse prenatal development may promote obesity, but evidence for the role of prenatal overnutrition in dietary intake in young children is scant.

METHODS

We used data from the National Health and Nutrition Examination Survey 2009-2014. Our study sample included 1782 U.S. children 2-5 years old with available birth weight and two 24-h dietary recalls. We used linear and Poisson regression to examine the association of birth weight (LBW < 2500 g, HBW > 4100 g) and 2-day average intake of dietary variables. We tested interactions between birthweight and breastfeeding (breastfed > 5 months vs. not breastfed or breastfed 0-5 months), and report breastfeeding-specific results.

RESULTS

In multivariable regression analysis, in boys, LBW was associated with 2.4 (95% CI - 4.3, - 0.5) lower percent of kcal from solid fat; lower sugar intake, marginally lower saturated and total fat intake, and 0.6 cup (95% CI 0.1, 1.0) greater vegetable consumption; HBW was marginally associated with lower fat. Birth weight was unrelated to diet in girls. Breastfeeding modified associations between birth weight and dietary intake, but the direction of modification was mixed.

DISCUSSION

Our findings do not support the hypothesis that LBW or HBW are associated with adverse diet consumption in preschool age U.S. children. Improved understanding of the role of early life development of dietary behavior requires further research on the development of appetitive traits and the role of the family and preschool food environments.

Expression and functional characterisation of System L amino acid transporters in the human term placenta

BACKGROUND

System L transporters LAT1 (SLC7A5) and LAT2 (SLC7A8) mediate the uptake of large, neutral amino acids in the human placenta. Many System L substrates are essential amino acids, thus representing crucial nutrients for the growing fetus. Both LAT isoforms are expressed in the human placenta, but the relative contribution of LAT1 and LAT2 to placental System L transport and their subcellular localisation are not well established. Moreover, the influence of maternal body mass index (BMI) on placental System L amino acid transport is poorly understood. Therefore the aims of this study were to determine: i) the relative contribution of the LAT isoforms to System L transport activity in primary human trophoblast (PHT) cells isolated from term placenta; ii) the subcellular localisation of LAT transporters in human placenta; and iii) placental expression and activity of System L transporters in response to maternal overweight/obesity.

METHODS

System L mediated leucine uptake was measured in PHT cells after treatment with si-RNA targeting LAT1 and/or LAT2. The localisation of LAT isoforms was studied in isolated microvillous plasma membranes (MVM) and basal membranes (BM) by Western blot analysis. Results were confirmed by immunohistochemistry in sections of human term placenta. Expression and activity System L transporters was measured in isolated MVM from women with varying pre-pregnancy BMI.

RESULTS

Both LAT1 and LAT2 isoforms contribute to System L transport activity in primary trophoblast cells from human term placenta. LAT1 and LAT2 transporters are highly expressed in the MVM of the syncytiotrophoblast layer at term. LAT2 is also localised in the basal membrane and in endothelial cells lining the fetal capillaries. Measurements in isolated MVM vesicles indicate that System L transporter expression and activity is not influenced by maternal BMI.

CONCLUSIONS

LAT1 and LAT2 are present and functional in the syncytiotrophoblast MVM, whereas LAT2 is also expressed in the BM and in the fetal capillary endothelium. In contrast to placental System A and beta amino acid transporters, MVM System L activity is unaffected by maternal overweight/obesity.