Dietary intakes of women during pregnancy in low- and middle-income countries

Abstract

Objective: To provide a better understanding of dietary intakes of pregnant women in low- and middle-income countries.

Design: Systematic review was performed to identify relevant studies which reported nutrient intakes or food consumption of pregnant women in developing countries. Macronutrient and micronutrient intakes were compared by region and the FAO/WHO Estimated Average Requirements. Food consumption was summarized by region.

Setting: Developing countries in Africa, Asia, and the Caribbean and Central/South America.

Subjects: Pregnant women in the second or third trimester of their pregnancies.

Results: From a total of 1499 retrieved articles, sixty-two relevant studies were analysed. The ranges of mean/median intakes of energy, fat, protein and carbohydrate were relatively higher in women residing in the Caribbean and Central/South America than in Africa and Asia. Percentages of energy from carbohydrate and fat varied inversely across studies in all regions, whereas percentage of energy from protein was relatively stable. Among selected micronutrients, folate and Fe intakes were most frequently below the Estimated Average Requirements, followed by Ca and Zn. Usual dietary patterns were heavily cereal based across regions.

Conclusions: Imbalanced macronutrients, inadequate micronutrient intakes and predominantly plant-based diets were common features of the diet of pregnant women in developing countries. Cohesive public health efforts involving improving access to nutrient-rich local foods, micronutrient supplementation and fortification are needed to improve the nutrition of pregnant women in developing countries.

Fig. 1

Flow diagram of study selection (LAC refers to Mexico, the Caribbean and Central/South America)

Fig. 2

(a) Energy and (b) protein intakes of pregnant women by region: vertical reference lines are the medians of energy and protein intakes across studies; •, mean values; ⧫, median values; LAC refers to Mexico, the Caribbean and Central/South America; numbers in square brackets represent reference numbers

Fig. 3

(a) Fat and (b) carbohydrate intakes of pregnant women by region: vertical reference lines are the medians of fat and carbohydrate intakes across studies; •, mean values; ⧫, median values; LAC refers to Mexico, the Caribbean and Central/South America; numbers in square brackets represent reference numbers

Fig. 4

Contributions of macronutrients to total energy intakes of pregnant women by region: •, protein as a percentage of total energy intake; △, fat as a percentage of total energy intake; ⧫, carbohydrate as a percentage of total energy intake; LAC refers to Mexico, the Caribbean and Central/South America; numbers in square brackets represent reference numbers. Percentages of total energy intake of studies in the present review are compared with the ranges of recommended intake (represented by vertical reference lines; 10–15 % of total energy for protein, 15–30 % of total energy for fat and 55–75 % of total energy for carbohydrate) as defined by WHO/FAO^{( 28 )}. Only studies with intake information available for all three macronutrients are shown

Fig. 5

(a) Vitamin A and (b) vitamin C intakes of pregnant women by region: •, mean values; ⧫, median values; LAC refers to Mexico, the Caribbean and Central/South America; numbers in square brackets represent reference numbers. Estimated mean or median vitamin A and vitamin C intakes of studies in the present review are compared with the Estimated Average Requirement (represented by vertical lines; 571 μg RE (retinol equivalents) for vitamin A and 46 mg for vitamin C)^{( 24 )}

Fig. 6

(a) Thiamin, (b) riboflavin, (c) niacin and (d) folate intakes of pregnant women by region: •, mean values; ⧫, median values; ○, folic acid (μg); LAC refers to Mexico, the Caribbean and Central/South America; numbers in square brackets represent reference numbers. Estimated mean or median thiamin, riboflavin, niacin and folate intakes of studies in the present review are compared with the Estimated Average Requirement (represented by vertical lines; 1·2 mg for thiamin and riboflavin, 14 mg NE (niacin equivalents) for niacin and 480 μg DFE (dietary folate equivalents) for folate)^{( 24 )}

Fig. 7

(a) Iron, (b) zinc and (c) calcium intakes of pregnant women by region: •, mean values; ⧫, median values; LAC refers to Mexico, the Caribbean and Central/South America; numbers in square brackets represent reference numbers. Estimated mean or median iron, zinc and calcium intakes of studies in the present review are compared with the Estimated Average Requirement (represented by vertical lines; 40 mg for iron, 11·7 mg for zinc and 833 mg for calcium)^{( 24 )}