Prenatal Micronutrient Supplementation Improves Offspring Survival

In a new study designed to better understand which micronutrients and food supplementation best help counteract nutritional insult in fetal life, researchers investigated how prenatal multiple micronutrient supplementation (MMS) and early food supplementation affected maternal hemoglobin levels at 30 weeks’ gestation, birth weight, and infant and child (younger than 5 years) mortality.

The study, which was conducted in Matlab, Bangladesh, followed 4436 pregnant women who were randomized into 6 groups (Table). The micronutrients included varying amounts of folic acid and iron, depending on the group, and food supplementation consisted of powder packs containing 608 kilocalories given 6 days per week. The results showed only marginal improvement in maternal hemoglobin levels at 30 weeks’ gestation and no affect on birth weight. However, survival of offspring was substantially improved for the women who received MMS and early invitation to food supplementation.

Early invitation to food supplementation (9 week’s gestation)

739

MINIMat, Maternal and Infant Nutrition Interventions in Matlab; MMS, multiple micronutrient supplementation.

*Contains 15 micronutrients, including 30 mg of iron and 400 micrograms of folic acid.

Data from Persson LA et al. JAMA. 2012.1

The group of women randomized to MMS with usual invitation to food supplementation had the highest offspring mortality rates and a significantly higher incidence of spontaneous abortions. According to the study authors, these findings suggest that satisfactory dietary intake in early pregnancy may be crucial for placenta function and fetal development.

Previous trials of prenatal multiple micronutrients have found small increases in birth weight compared with folic acid/iron supplementation alone^2,3 and a slight reduction in the number of neonates who were small for gestational age.⁴ However, this new study is the first to show that providing a combination of multiple micronutrients and food supplementation early in pregnancy can reduce childhood mortality rates.¹ It is also the first study in humans to assess the effect of timing of prenatal food supplementation on survival of offspring.

In animal studies, there are critical periods in the mother’s dietary intake in pregnancy that program metabolism and influence future health without affecting birth size.⁵ The study authors suggest that providing adequate nutrition early in pregnancy via food supplementation and MMS can potentially promote adequate responses of the offspring to the stresses at birth and to perinatal infections.^1,6

Pertinent Points:
- For underfed or impoverished women, multiple micronutrients, including iron and folic acid combined with early food supplementation, can decrease childhood mortality.
- Despite the study’s limited external validity, the findings provide important information about which nutrients are most beneficial during pregnancy and when taking them offers the most benefit.

References:

1. Persson LA, Arifeen S, Ekstrom EC, et al, for the MINIMat Study Team. Effects of prenatal micronutrient and early food supplementation on maternal hemoglobin, birth weight, and infant mortality among children in Bangladesh: the MINIMat randomized trial. JAMA. 2012;307:2050-2059.
2. Fall CH, Fisher DJ, Osmond C, Margetts BM, for the Maternal Micronutrient Supplementation Study Group. Multiple micronutrient supplementation during pregnancy in low-income countries: a meta-analysis of effects on birth size and length of gestation. Food Nutr Bull. 2009;30(suppl):S533-S546.
3. Margetts BM, Fall CH, Ronsmans C, et al, for the Maternal Micronutrient Supplementation Study Group. Multiple micronutrient supplementation during pregnancy in low-income countries: review of methods and characteristics of studies included in the meta-analysis. Food Nutr Bull. 2009;30(suppl):S517-S526.
4. Haider BA, Yakoob MY, Bhutta ZA. Effect of multiple micronutrient supplementation during pregnancy on maternal and birth outcomes. BMC Public Health. 2011;11(suppl 3):S19.
5. Hoet JJ, Hanson MA. Intrauterine nutrition: its importance during critical periods for cardiovascular and endocrine development. J Physiol. 1999;514(pt 3):617-627.6. McArdle HJ, Ashworth CJ. Micronutrients in fetal growth and development. Br Med Bull. 1999;55:499-510.