Dataset Information

The Effect of Maternal Multiple Micronutrient Supplementation on Female Early Infant Mortality Is Fully Mediated by Increased Gestation Duration and Intrauterine Growth.

ABSTRACT:

Background

Maternal micronutrient supplementation in pregnancy (MMS) has been shown to improve birth weight among infants in low- and middle-income countries. Recent evidence suggests that the survival benefits of MMS are greater for female infants compared to male infants, but the mechanisms leading to differential effects remain unclear.

Objective

The objective of this study was to examine the potential mechanisms through which MMS acts on infant mortality among Tanzanian infants.

Methods

We used data collected from pregnant women and newborns in a randomized, double-blind, placebo-controlled trial of MMS conducted in Tanzania to examine mediators of the effect of MMS on 6-wk infant mortality (NCT00197548). Causal mediation analyses with the counterfactual approach were conducted to assess the contributions of MMS on survival via their effects on birth weight, gestational age, weight-for-gestational age, and the joint effect of gestational age and weight-for-gestational age. The weighting method allowed for interaction between gestational age and weight-for-gestational age.

Results

Among 7486 newborns, the effect of MMS on 6-wk survival was fully mediated (100%) through the joint effect of gestational age and weight-for-gestational age. MMS was also found to have a significant natural indirect effect through increased birth weight (P-value < 0.001) that explained 75% of the total effect on 6-wk mortality. When analyses were stratified by sex, changes in gestational age and weight-for-gestational age fully mediated the mortality effect among female infants (n = 3570), but these mediators only explained 34% of the effect among males (n = 3833).

Conclusions

The potential sex-specific effects of MMS on mortality may be a result of differences in mechanisms related to birth outcomes. In the context of the Tanzanian trial, the observed effect of MMS on 6-wk mortality for female infants was entirely mediated by increased gestation duration and improved intrauterine growth, while these mechanisms did not appear to be major contributors among male infants.

SUBMITTER: Quinn MK

PROVIDER: S-EPMC7308623 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Publications

The Effect of Maternal Multiple Micronutrient Supplementation on Female Early Infant Mortality Is Fully Mediated by Increased Gestation Duration and Intrauterine Growth.

Quinn Mary K MK Smith Emily R ER Williams Paige L PL Urassa Willy W Shi Joy J Msamanga Gernard G Fawzi Wafaie W WW Sudfeld Christopher R CR

The Journal of nutrition 20200201 2

<h4>Background</h4>Maternal micronutrient supplementation in pregnancy (MMS) has been shown to improve birth weight among infants in low- and middle-income countries. Recent evidence suggests that the survival benefits of MMS are greater for female infants compared to male infants, but the mechanisms leading to differential effects remain unclear.<h4>Objective</h4>The objective of this study was to examine the potential mechanisms through which MMS acts on infant mortality among Tanzanian infant ...[more]

PMID: 31605616

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Dataset Information

The Effect of Maternal Multiple Micronutrient Supplementation on Female Early Infant Mortality Is Fully Mediated by Increased Gestation Duration and Intrauterine Growth.

Background

Objective

Methods

Results

Conclusions

Publications

The Effect of Maternal Multiple Micronutrient Supplementation on Female Early Infant Mortality Is Fully Mediated by Increased Gestation Duration and Intrauterine Growth.

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