Preconception Micronutrient Supplementation Affects Maternal BMI and Body Composition Postpartum: A Randomized Controlled Trial in Vietnam

BACKGROUND

Although there is growing evidence on the role of preconception nutrition for birth outcomes, limited evidence exists for its effects on maternal health.

OBJECTIVES

This study evaluates the impact of preconception micronutrient supplementation on maternal BMI (kg/m2) and body composition at 6 to 7 y postpartum (PP).

METHODS

We followed females who participated in a randomized controlled trial of preconception supplementation in Vietnam and delivered live offspring (n = 1599). Females received weekly supplements containing either 2800 μg folic acid (FA) only, 60 mg iron and 2800 μg FA (IFA), or multiple micronutrients (MMs) (15 micronutrients including IFA) from baseline until conception followed by daily prenatal IFA supplements until delivery. Height, weight, mid-upper arm circumference, triceps skinfold, and waist-hip circumference were measured at recruitment and at 1, 2, and 6 to 7 y PP. Body fat was assessed using bioelectric impedance at 6 to 7 y PP (n = 867). Group comparisons were made using analysis of variance or chi-square tests and general linear models for adjusted models.

RESULTS

At 6 to 7 y PP, we found significant differences (P < 0.05) by treatment group for mean percent fat (MM: 29.2%; IFA: 27.6%; FA: 27.8%), absolute fat mass (MM: 15.1 kg; IFA: 14.0 kg; FA: 14.3 kg), and prevalence of underweight based on BMI < 18.5 (MM: 5.8%; IFA: 10.3%; FA: 14.3%). Mean BMI and triceps skinfold thickness were higher in the MM group, but these differences were not statistically significant; the differences in absolute fat mass were also attenuated after controlling for body weight. No differences were observed for fat-free mass, prevalence of overweight (BMI >23), or other anthropometric measurements.

CONCLUSIONS

Preconception MM supplementation was associated with lower prevalence of underweight and higher percent fat when compared with IFA and/or FA only. Preconception micronutrient interventions may have long-term effects on maternal health and merit further examination. This trial was registered at clinicaltrials.gov as NCT01665378.

Maternal and Offspring Fatty Acid Desaturase Variants, Prenatal DHA Supplementation, and Dietary n-6:n-3 Fatty Acid Ratio in Relation to Cardiometabolic Health in Mexican Children

BACKGROUND

Single-nucleotide polymorphisms (SNPs) in fatty acid desaturase (FADS) genes may modify dietary fatty acid requirements and influence cardiometabolic health (CMH).

OBJECTIVES

We evaluated the role of selected variants in maternal and offspring FADS genes on offspring CMH at the age of 11 y and assessed interactions of genotype with diet quality and prenatal docosahexaenoic acid (DHA) supplementation.

METHODS

We used data from offspring (n = 203) born to females who participated in a randomized controlled trial of DHA supplementation (400 mg/d) from midgestation to delivery. We generated a metabolic syndrome (MetS) score from body mass index, high-density lipoprotein cholesterol, triglycerides, systolic blood pressure, and fasting glucose and identified 6 distinct haplotypes from 5 offspring FADS SNPs. Dietary n-6 (ω-6):n-3 fatty acid ratios were derived from 24-h recall data (n = 141). We used generalized linear models to test associations of offspring diet and FADS haplotypes with MetS score and interactions of maternal and offspring FADS SNP rs174602 with prenatal treatment group and dietary n-6:n-3 ratio on MetS score.

RESULTS

Associations between FADS haplotypes and MetS score were null. Offspring SNP rs174602 did not modify the association of prenatal DHA supplementation with MetS score. Among children with TT or TC genotype for SNP rs174602 (n = 88), those in the highest n-6:n-3 ratio tertile (>8.61) had higher MetS score relative to the lowest tertile [<6.67) (Δ= 0.36; 95% confidence interval (CI): 0.03, 0.69]. Among children with CC genotype (n = 53), those in the highest n-6:n-3 ratio tertile had a lower MetS score relative to the lowest tertile (Δ= -0.23; 95% CI: -0.61, 0.16).

CONCLUSIONS

There was evidence of an interaction of offspring FADS SNP rs174602 with current dietary polyunsaturated fatty acid intake, but not with prenatal DHA supplementation, on MetS score. Further studies may help to determine the utility of targeted supplementation strategies and dietary recommendations based on genetic profile.

Effects of prenatal docosahexaenoic acid supplementation on offspring cardiometabolic health at 11 years differs by maternal single nucleotide polymorphism rs174602: follow-up of a randomized controlled trial in Mexico

BACKGROUND

There is limited evidence regarding long-term effects of prenatal docosahexaenoic acid (DHA) supplementation on offspring cardiometabolic health (CMH). Inconsistent results may be attributable to variants of fatty acid desaturase (FADS) genes.

OBJECTIVE

We aimed to evaluate the effect of prenatal DHA supplementation on offspring CMH and investigate effect modification by maternal FADS2 single nucleotide polymorphism (SNP) rs174602.

METHODS

We used follow-up data from a double-blind, randomized controlled trial in Mexico in which pregnant females received 400 mg/d of algal DHA or placebo from midgestation until delivery. The study sample included 314 offspring with data at age 11 y and maternal FADS genetic data (DHA: n = 160; Placebo: n = 154). We derived a Metabolic Syndrome (MetS) score from body mass index, HDL, triglycerides, fasting glucose concentrations, and systolic blood pressure. Generalized linear models were used to evaluate the effect of the intervention on offspring MetS score and test interactions between treatment group and genotype, adjusting for maternal, offspring, and household factors.

RESULTS

Offspring MetS score did not differ significantly by treatment group. We observed evidence of effect modification by maternal SNP rs174602 (P = 0.001); offspring of maternal TT genotype who received DHA had lower MetS score relative to the placebo group (DHA (mean ± standard error of the mean (SEM)): -0.21 ± 0.11, n = 21; Placebo: 0.05 ± 0.11, n = 23; Δ= -0.26 (95% CI: -0.55, 0.04), P = 0.09); among CC maternal genotype carriers, offspring of mothers who received DHA had higher MetS score (0.18 ± 0.06, n = 62) relative to the placebo group (-0.05 ± 0.06, n = 65, Δ=0.24 (0.06, 0.41), P < 0.01).

CONCLUSION

The effect of prenatal DHA supplementation on offspring MetS score differed by maternal FADS SNP rs174602. These findings further support incorporating genetic analysis of FADS polymorphisms in DHA supplementation trials.

CLINICAL TRIAL DETAILS

This trial was registered at clinicaltrials.gov as NCT00646360.