Background

Gestational weight gain (GWG) is a modifiable factor associated with maternal and child health outcomes, but the relationship between diet quality and GWG has not been evaluated using metrics validated for low-income and middle-income countries (LMICs).

Objective

This study aimed to investigate relationships between diet quality, socioeconomic characteristics, and GWG adequacy using the novel Global Diet Quality Score (GDQS), the first diet quality indicator validated for use across LMIC.

Methods

Weights of pregnant women enrolled between 12 and 27 wk of gestation (N = 7577) were recorded in Dar es Salaam, Tanzania, from 2001 to 2005 during a prenatal micronutrient supplementation trial. GWG adequacy was the ratio of measured GWG to Institute of Medicine-recommended GWG, categorized into severely inadequate (<70%), inadequate (70 to <90%), adequate (90 to <125%), or excessive (≥125%). Dietary data were collected using 24-h recalls. Multinomial logit models were used to estimate relationships between GDQS tercile, macronutrient intake, nutritional status, and socioeconomic characteristics and GWG.

Results

GDQS scores in the second [relative risk (RR): 0.82; 95% confidence interval (CI): 0.70, 0.97] tercile were associated with lower risk of inadequate weight gain than those in the first tercile. Increased protein intake was associated with higher risk of severely inadequate GWG (RR: 1.06; 95% CI: 1.02, 1.09). Nutritional status and socioeconomic factors were associated with GWG: underweight prepregnancy BMI (in kg/m²) with a higher risk of severely inadequate GWG (RR: 1.49; 95% CI: 1.12, 1.99), overweight or obese BMI with a higher risk of excessive GWG (RR: 6.80; 95% CI: 5.34, 8.66), and a higher education (RR: 0.61; 95% CI: 0.42, 0.89), wealth (RR: 0.68; 95% CI: 0.48, 0.80), and height (RR: 0.96; 95% CI: 0.95, 0.98) with a lower risk of severely inadequate GWG.

Conclusions

Dietary indicators showed few associations with GWG. However, stronger relationships were revealed between GWG, nutritional status, and several socioeconomic factors.This trial was registered at clinicaltrials.gov as NCT00197548.

Context

Approximately 7.3 million births occur annually among adolescents in low- and middle-income countries. Pregnant adolescents constitute a nutritionally vulnerable group that could benefit from intervention to mitigate the mortality and adverse birth outcomes associated with adolescent pregnancy.

Objective

The aim of this systematic review and meta-analysis was to assess the following: (1) the effect of multiple-micronutrient (MMN) supplementation vs iron and folic acid (IFA) supplementation among adolescents on maternal morbidity, birth outcomes, and mortality outcomes, (2) the effects of MMN supplementation in adolescents compared with the effects in adult women, and (3) the effect modification, if any, of MMN supplementation by baseline and geographic characteristics of adolescents.

Data sources

MEDLINE and Cochrane databases were searched, along with the reference lists of relevant reviews.

Study selection

Multiple-micronutrient supplementation trials in pregnancy that were conducted in a low- or middle-income country and had included at least 100 adolescents (10-19 years of age) were eligible for inclusion. Two independent reviewers assessed study eligibility.

Data extraction

Thirteen randomized controlled trials conducted in Africa and Asia were identified from 1792 reviews and 1578 original trials. Individual-level data was shared by study collaborators and was checked for completeness and extreme values. One- and two-stage individual participant data meta-analyses were conducted using data from randomized controlled trials of MMN supplementation.

Results

A total of 15 283 adolescents and 44 499 adult women with singleton births were included in the individual participant data meta-analyses of MMN supplementation vs IFA supplementation. In adolescents, MMN supplementation reduced low birth weight (1-stage OR = 0.87, 95%CI 0.77-0.97; 2-stage OR = 0.81; 95%CI 0.74-0.88), preterm birth (1-stage OR = 0.88, 95%CI 0.80-0.98; 2-stage OR = 0.86, 95%CI 0.79-0.95), and small-for-gestational-age births (1-stage OR = 0.90, 95%CI 0.81-1.00; 2-stage OR = 0.86, 95%CI 0.79-0.95) when compared with IFA supplementation. The effects of MMN supplementation did not differ between adolescents and older women, although a potentially greater reduction in small-for-gestational-age births was observed among adolescents. Effect modification by baseline characteristics and geographic region was inconclusive.

Conclusions

Multiple-micronutrient supplementation can improve birth outcomes among pregnant adolescents in low- and middle-income countries. Policy related to antenatal care in these settings should prioritize MMN supplementation over the currently recommended IFA supplementation for all pregnant women, especially adolescents.