Associations of Gestational Diabetes Mellitus and Excessive Gestational Weight Gain with Offspring Obesity Risk.

OBJECTIVE: Gestational diabetes mellitus (GDM) and gestational weight gain (GWG) are important risk factors that are known to affect offspring growth, but these outcomes are inconsistent and it remains unknown if both risk factors have a synergetic effect on early childhood growth. The present study aimed to conduct offspring body mass index-for-age Z-scores (BMIZ) trajectories and to evaluate the independent and interactive effect of the status of GDM and excessive GWG on the risks of overweight/obesity from birth to 24 months of age. METHODS: A total of 7949 mother-child pairs were enrolled in this study. The weight and length of children were measured at birth, 6, 12, and 24 months of age to calculate BMIZ. RESULTS: The status of GDM was positively associated with offspring BMIZ and risk of macrosomia at birth but was not associated with offspring BMIZ or the risks of overweight/obesity at 6, 12, and 24 months of age. In contrast, excessive GWG was positively linked to offspring BMIZ, the stable high BMIZ trajectory pattern, and risks of overweight/obesity in the first 24 months of age. These two risk factors also had a significant synergistic effect on macrosomia at birth, but the interactive effect was only significant in boys during the follow-up years in the sex-stratified analyses. CONCLUSION: The maternal GWG was a more pronounced predictor than GDM with relation to BMIZ and risk of overweight/obesity in early childhood. The interactive effect between these risk factors on offspring overweight/obesity may vary by sex.

Prenatal and postnatal cadmium exposure and cellular immune responses among pre-school children.

BACKGROUND: Experimental studies have demonstrated that cadmium exposure induces alterations on immune function, but epidemiological evidence is lacking. OBJECTIVE: To examine the associations between prenatal and postnatal cadmium exposure and cellular immune responses among pre-school children. METHODS: Pre-school aged children (n = 407) were followed from a prospective birth cohort study in Wuhan, China. Maternal urinary and children's plasma cadmium concentrations were measured as biomarkers of prenatal and postnatal cadmium exposure, respectively. Children's cellular immune responses were assessed by peripheral blood T lymphocyte subsets and plasma cytokines. Multivariable adjusted models were applied to estimate the associations of prenatal and postnatal cadmium exposure with T lymphocyte subsets and cytokines, and the effect modification by child gender were also examined. RESULTS: Maternal urinary cadmium was associated with reduced absolute counts of CD3+CD4+ cells (-12.45%; 95% CI: -23.74%, 0.40% for the highest vs. lowest quartile; p for trend = 0.045). Inverse associations of maternal urinary cadmium with %CD3+CD4+ cells and CD4+/CD8+ ratio were only observed among females (both p-interaction < 0.050); whereas an inverse association with absolute counts of CD3+CD8+ cells was only observed among males (p-interaction = 0.057). Positive associations of maternal urinary cadmium with %CD3+CD4+ cells, interleukin-4 (IL-4), and IL-6 were only observed among females, although there were no significant interactions. We observed no clear associations of children's plasma cadmium with T lymphocyte subsets and cytokines. CONCLUSION: Prenatal but not postnatal cadmium exposure was associated with sex-specific alterations on children's cellular immune responses.