Maternal Serum 25-Hydroxyvitamin D Concentrations during Pregnancy and Infant Birthweight for Gestational Age: a Three-Cohort Study.

BACKGROUND: In response to inconsistent findings, we investigated associations between maternal serum 25-hydroxyvitamin D [25(OH)D] concentrations and infant birthweight for gestational age (BW/GA), including potential effect modification by maternal race/ethnicity and infant sex. METHODS: Data from 2558 pregnant women were combined in a nested case-control study (preterm and term) sampled from three cohorts: the Omega study, the Pregnancy, Infection and Nutrition study, and the Pregnancy Outcomes and Community Health study. Maternal 25(OH)D concentrations were sampled at 4 to 29 weeks gestation (80% 14-26 weeks). BW/GA was modelled as sex and gestational age-specific birthweight z-scores. General linear regression models (adjusting for age, education, parity, pre-pregnancy body mass index, season at blood draw, and smoking) assessed 25(OH)D concentrations in relation to BW/GA. RESULTS: Among non-Hispanic Black women, the positive association between 25(OH)D concentrations and BW/GA was of similar magnitude in pregnancies with female or male infants [beta (ß) = 0.015, standard error (SE) = 0.007, P = 0.025; ß = 0.018, SE = 0.006, P = 0.003, respectively]. Among non-Hispanic White women, 25(OH)D-BW/GA association was observed only with male infants, and the effect size was lower (ß = 0.008, SE = 0.003, P = 0.02). CONCLUSIONS: Maternal serum concentrations of 25(OH)D in early and mid-pregnancy were positively associated with BW/GA among non-Hispanic Black male and female infants and non-Hispanic White male infants. Effect modification by race/ethnicity may be due, in part, to overall lower concentrations of 25(OH)D in non-Hispanic Blacks. Reasons for effect modification by infant sex remain unclear.

Effect of supplementation with a lipid-based nutrient supplement on the micronutrient status of children aged 6-18 months living in the rural region of Intibucá, Honduras.

BACKGROUND: Lipid-based nutrient supplements (LNS) have been effective in the treatment of acute malnutrition among children. We evaluated the use of LNS supplementation for improving the micronutrient status of young children. METHODS: A 12-month randomised controlled trial was conducted among children aged 6-18 months living in Intibucá, Honduras. Communities (n = 18) were randomised into clusters matched by poverty indicators (9 intervention, n = 160 and 9 controls, n = 140). Intervention participants received LNS. All children received food vouchers and nutrition education. Primary outcomes included measures of micronutrient status: at baseline, 6 and 12 months' blood were collected for assessment of folate, iron, zinc, riboflavin, and vitamin B12 status; haemoglobin was measured every 3 months; and dietary and anthropometry collected monthly. Longitudinal analyses were based on intent to treat and LNS adherence. Generalised estimating equations were used in the estimation of generalised linear regression models specified for the data. RESULTS: At 6-month follow-up, children in the intervention group had a lower proportion classified as deficient for B12 (43.6%) compared with the control (67.7%; P = 0.03). The intervention group had a higher mean concentration for folate at 6 months (P = 0.06), and improvements continued through 12 months for folate (P = 0.002) and vitamin A deficiency (P = 0.03). This pattern of results, with improved significance, remained in subanalysis based on LNS adherence. CONCLUSION: These data demonstrate that LNS improved select micronutrient status in young non-malnourished Honduran children.

Periconceptional glycaemic load and intake of sugars and their association with neural tube defects in offspring.

In a California population, we previously observed increased neural tube defect (NTD) risks associated with maternal intakes of periconceptional diets predicting higher glycaemic responses and higher sucrose. Our objective here was to replicate these results in a larger study of multiple regions within the United States. This population-based case-control study included deliveries from 1997 to 2003 from the National Birth Defects Prevention Study. NTD cases were infants or fetuses born with spina bifida or anencephaly. Infants without malformations were eligible as controls. Interview participation was 71% among case mothers and 68% among control mothers. There were 720 NTD case and 4699 control mothers with completed interviews included in analyses. Diet was assessed using a 58-item food frequency questionnaire focusing on the year before conception, whereas cereals, beverages and supplement use was assessed periconceptionally. We found no increased risks of NTD-affected pregnancies with increased intakes (adjusted for kcal/day) of sucrose, glucose, fructose or with maternal diets with a higher glycaemic load. The reasons for current findings to be inconsistent with previous findings are unknown.

Childbearing is not associated with young women's long-term obesity risk.

OBJECTIVE: Contemporary childbearing is associated with greater gestational weight gain and postpartum weight retention than in previous decades, potentially leading to a more pronounced effect of childbearing on women's long-term obesity risk. Previous work on the association of childbearing with women's long-term obesity risk mostly examined births in the 1970s and 1980s and produced mixed results. The association of childbearing and obesity incidence in a diverse, contemporary sample of 2731 US women was estimated. METHODS: Propensity-score (PS) matching was used for confounding control when estimating the effect of incident parity (1996-2001) on 7-year incident obesity (BMI≥30 kg/m(2) ) (2001-2008). RESULTS: In the sample, 19.3% of parous women became obese, whereas 16.1% of unmatched nulliparous women did. After PS matching without and with replacement, the differences in obesity incidence were, respectively, 0.0 percentage points (ppts) (95% CI: -4.7 to 4.7) and 0.9 ppts (95% CI: -4.9 to 6.7). Results were similar in analyses of prevalent parity and obesity in 2008 (n = 6601) conducted to explore possible selection bias. CONCLUSIONS: These results imply that, in contemporary US parous women in their late 20s and early 30s, childbearing may not increase obesity incidence.

Pregravid weight is associated with prior dietary restraint and psychosocial factors during pregnancy.

The objective of this study was to investigate the association of pregravid weight status, previous dietary restraint, and psychosocial factors during pregnancy. We used data from the Pregnancy, Infection, and Nutrition study, which recruited 2,006 women at prenatal clinics before 20 weeks' gestation who were >16 years and English speaking. Institute of Medicine BMI cut points of underweight (<19.8), normal weight (19.8-26.0), overweight (>26.0-29.0), obese (>29.0-34.9), and an additional category extremely obese (> or =35.0), were used to categorize weight status. Eight psychosocial measures and dietary restraint were assessed with regard to BMI; perceived stress, trait anxiety, depressive symptoms, internal locus of control (LOC), chance LOC, powerful others LOC, self-esteem, and mastery. Linear regression was used to estimate associations, controlling for potential confounders. A significant trend was found between increasing pregravid weight categories and increasing scores for perceived stress, trait anxiety, depressive symptoms, powerful others LOC and dietary restraint, and decreasing scores for self-esteem and mastery. In adjusted models, pregravid obesity was independently associated with perceived stress, trait anxiety, and depressive symptoms. Extreme obesity was independently associated with all measures except internal LOC. A strong linear association was found between increasing weight categories and dietary restraint. In conclusion, as pregravid weight increased, pregnant women were at greater risk of reporting higher scores on negative psychosocial state and dietary restraints, and reporting lower score on positive personal dispositions.

Psychosocial determinants of adequacy of gestational weight gain.

Pregnancy is a critical time window for evaluating weight gain on subsequent risk for obesity among women of childbearing age. The purpose of this investigation was to determine whether symptoms of depression, anxiety, stress, self-esteem, and fetal health locus of control (FHLC) beliefs were significant risk factors for adequacy of gestational weight gain (GWG) when maternal sociodemographic characteristics and health behaviors were considered. A total of 1,605 women were prospectively followed from < or =20 weeks' gestation through delivery. Participants completed standard self-report questionnaires. Adequacy of GWG was expressed as the ratio of observed/expected weight gain based on Institute of Medicine recommendations. Multivariate ANOVA models were conducted and generalized linear models were performed to calculate risk ratios. Higher depressive symptoms reported throughout pregnancy were significantly associated with higher adequacy ratios. Stronger beliefs in chance in determining fetal health predicted inadequate relative to adequate GWG and was positively associated with larger GWG ratios overall. Several relationships were attenuated when adjusted for covariates. The relationship between psychosocial status and adequacy of GWG is significantly impacted by maternal sociodemographic factors and health practices engaged in during pregnancy. Women who tend to believe that external factors primarily determine fetal health appear to be more vulnerable to nonadherence to clinical GWG guidelines. These results have important implications for targeting prevention and intervention efforts for improving maternal and fetal outcomes secondary to GWG patterns.