Pre-pregnancy body mass index (BMI) and maternal gestational weight gain are positively associated with birth outcomes in rural Malawi

Abstract

BackgroundWhereas poor maternal nutritional status before and during pregnancy is widely associated with adverse birth outcomes, studies quantifying this association in low income countries are scarce. We examined whether maternal pre-pregnancy body mass index (BMI) and weight gain during pregnancy are associated with birth outcomes in rural Malawi.MethodsWe analyzed the associations between pre-pregnancy BMI and average weekly gestational weight gain (WWG) and birth outcomes [duration of gestation, birth weight, length-for-age z-score (LAZ), and head circumference-for-age z-score (HCZ)]. We also determined whether women with low or high pre-pregnancy BMI or women with inadequate or excessive WWG were at increased risk of adverse birth outcomes.ResultsThe analyses included 1287 women with a mean BMI of 21.8 kg/m2, of whom 5.9% were underweight (< 18.5 kg/m2), 10.9% were overweight (≥ 25 kg/m2), 71.8% had low WWG [below the lower limit of the Institute of Medicine (IOM) recommendation], and 5.2% had high WWG (above IOM recommendation). In adjusted models, pre-pregnancy BMI was not associated with duration of pregnancy (p = 0.926), but was positively associated with birth weight and HCZ (<0.001 and p = 0.003, respectively). WWG was positively associated with duration of gestation (p = 0.031), birth weight (p<0.001), LAZ (p<0.001), and HCZ (p<0.001). Compared to normal weight women, underweight women were at increased risk of having stunted infants (p = 0.029). Women with low WWG were at increased risk of having infants with low birth weight (p = 0.006) and small head circumference (p = 0.024) compared to those with normal weight gain. Those with high BMI or high WWG were not at increased risk of adverse birth outcomes.ConclusionsWWG is an important predictor of birth outcomes in rural Malawi. The high prevalence of inadequate WWG compared to low pre-pregnancy BMI highlights the need to investigate causes of inadequate weight gain in this region.

Gestational weight gain and newborn anthropometric outcomes in rural Bangladesh

“…In the RDNS, GWG rate was not associated with gestational age at delivery. This is consistent with findings from the United States, Ireland, and Taiwan (Dahly et al, ; Huang et al, ; Sharma et al, ), but not with several other reports suggesting that low GWG is associated with prematurity (Black, Sacks, et al, ; Enomoto et al, ; Li et al, ; Shin & Song, ) or duration of gestation (Gondwe et al, ). One potential explanation for these conflicting results is that most of the studies that have shown an association failed to adjust total GWG for gestational age at last measurement or otherwise account for the duration of pregnancy by calculating GWG rate (Sharma et al, ).…”

“…We found only two other studies in lower income countries that addressed the association between GWG and birth outcomes (Gondwe et al, 2018;Ota et al, 2011). In rural Malawi, women with low weekly weight gain were at increased risk of having infants with LBW and small head circumference (P = .024) than were those with normal weight gain (Gondwe et al, 2018). In Vietnam, GWG < 10 kg was associated with 90% greater odds of SGA than was GWG of 10-15 kg (Ota et al, 2011).…”

“…If these associations are causal, they suggest that achieving adequate GWG could be an important step in reducing the burden of unfavourable birth outcomes in a low-income setting with high rates of maternal undernutrition. We found only two other studies in lower income countries that addressed the association between GWG and birth outcomes (Gondwe et al, 2018;Ota et al, 2011). In rural Malawi, women with low weekly weight gain were at increased risk of having infants with LBW and small head circumference (P = .024) than were those with normal weight gain (Gondwe et al, 2018).…”

Poor maternal anthropometric status before conception is associated with a deleterious infant growth during the first year of life: a longitudinal preconceptional cohort

“…Gondwe et al in Malawi reported a higher risk of stunting at birth in infants born from underweight mothers during pregnancy as well as an association between inadequate GWG and a higher risk of LBW and SGA. 37 In our study, the infant's growth trajectory differed strongly as early as birth between infants born from mothers affected by obesity vs underweight, suggesting the effect of early maternal determinants. This observation is in line with the DOHaD concept.…”

“…In particular, in studies conducted in Sudan, Ghana, and South Africa, obesity during pregnancy was associated with macrosomia at birth. Gondwe et al in Malawi reported a higher risk of stunting at birth in infants born from underweight mothers during pregnancy as well as an association between inadequate GWG and a higher risk of LBW and SGA …”