Maternal Characteristics Affect Fetal Growth Response in the Women First Preconception Nutrition Trial

Abstract

The objective of this secondary analysis was to identify maternal characteristics that modified the effect of maternal supplements on newborn size. Participants included 1465 maternal–newborn dyads in Guatemala, India, and Pakistan. Supplementation commenced before conception (Arm 1) or late 1st trimester (Arm 2); Arm 3 received usual care. Characteristics included body mass index (BMI), stature, anemia, age, education, socio-economic status (SES), parity, and newborn sex. Newborn outcomes were z-scores for length (LAZ), weight (WAZ), and weight to length ratio-for-age (WLRAZ). Mixed-effect regression models included treatment arm, effect modifier, and arm * effect modifier interaction as predictors, controlling for site, characteristics, and sex. Parity (para-0 vs. para ≥1), anemia (anemia/no anemia), and sex were significant effect modifiers. Effect size (95% CI) for Arm 1 vs. 3 was larger for para-0 vs. ≥1 for all outcomes (LAZ 0.56 (0.28, 0.84, p < 0.001); WAZ 0.45 (0.20, 0.07, p < 0.001); WLRAZ 0.52 (0.17, 0.88, p < 0.01) but only length for Arm 2 vs. 3. Corresponding effects for para ≥1 were >0.02. Arm 3 z-scores were all very low for para-0, but not para ≥1. Para-0 and anemia effect sizes for Arm 1 were > Arm 2 for WAZ and WLRAZ, but not LAZ. Arm 1 and 2 had higher WAZ for newborn boys vs. girls. Maternal nulliparity and anemia were associated with impaired fetal growth that was substantially improved by nutrition intervention, especially when commenced prior to conception.

Prevalence and determinants of anemia among women of reproductive age in Thatta Pakistan: Findings from a cross-sectional study

“…More specifically, this study demonstrated that maternal anemia at baseline modified the treatment effect for birth outcomes such as birth weight, weight to length ratio as the improvements in these outcomes were significantly greater for Arm 1 (commencing nutrition intervention prior to conception) vs. Arm 2 (commencing same nutrition intervention early in gestation) [11].…”

“…Anemia is more prevalent in the rural areas of Pakistan, where it is often severe and linked to adverse health consequences such as postpartum hemorrhage, preterm delivery or stillbirth and low birth weight babies [10]. Furthermore, a study conducted by Hambidge et al 2019 found that anemia is an important and potentially modifiable risk factor on birth outcomes among rural Pakistani women [11]. More specifically, this study demonstrated that maternal anemia at baseline modified the treatment effect for birth outcomes such as birth weight, weight to length ratio as the improvements in these outcomes were significantly greater for Arm 1 (commencing nutrition intervention prior to conception) vs.…”

The importance of nutrition in pregnancy and lactation: lifelong consequences

“…In a recently completed multi-country trial in which the effects of a comprehensive nutrition intervention initiated prior to conception was compared to the same intervention initiated late in the first trimester (vs. no intervention), birth outcomes, including birth length and weight, LBW, SGA, and stunting, were strongly impacted by the nutritional intervention, with the largest effects in the preconception arm. 35 Nulliparity and preconception anemia were strong effect modifiers of the response to intervention with more modest effects by baseline BMI. 35,36 The WHO global guidance for antenatal care recommends several central nutritional and health interventions for a healthy pregnancy, including multiple micronutrient supplements containing iron-folic acid, calcium supplementation for prevention of preeclampsia in low J o u r n a l P r e -p r o o f intake contexts, and balanced energy and protein supplementation for undernourished populations to reduce low birthweight.…”

Perceptions of women, their husbands and healthcare providers about anemia in rural Pakistan: Findings from a qualitative exploratory study

“…Similarly, in rural areas of Pakistan anemia is associated with adverse health effects such as postpartum hemorrhage, preterm delivery or stillbirth, and low birth weight babies [ 10 ]. Further, a study conducted by Hambidge et al 2019 found that anemia is a significant and potentially changeable risk factor for birth outcomes among rural Pakistani women in rural Pakistan [ 21 ]. Despite the available data on the burden and magnitude of anemia in rural Pakistan, there is a dearth of literature on understanding the communities’ perceptions about anemia, its causes, consequences, and preventive measures.…”