Publications

OBJECTIVE: To estimate the associations between gestational weight gain (GWG) during pregnancy and neonatal outcomes in low and middle income countries.  DESIGN: Individual participant data meta-analysis. SETTING: Prospective pregnancy  studies from 24 low and middle income countries. MAIN OUTCOME MEASURES: Nine  neonatal outcomes related to timing (preterm birth) and anthropometry (weight,  length, and head circumference) at birth, stillbirths, and neonatal death.  ANALYSIS METHODS: A systematic search was conducted in PubMed, Embase, and Web of  Science which identified 53 prospective pregnancy studies published after the  year 2000 with data on GWG, timing and anthropometry at birth, and neonatal  mortality. GWG adequacy was defined as the ratio of the observed maternal weight  gain over the recommended weight gain based on the Institute of Medicine body  mass index specific guidelines, which are derived from data in high income  settings, and the INTERGROWTH-21st GWG standards. Study specific estimates,  adjusted for confounders, were generated and then pooled using random effects  meta-analysis models. Maternal age and body mass index before pregnancy were  examined as potential modifiers of the associations between GWG adequacy and  neonatal outcomes. RESULTS: Overall, 55% of participants had severely inadequate  (<70%) or moderately inadequate (70% to <90%) GWG, 22% had adequate GWG  (90-125%), and 23% had excessive GWG (≥125%). Severely inadequate GWG was  associated with a higher risk of low birthweight (adjusted relative risk 1.62,  95% confidence interval 1.51 to 1.72; 48 studies, 93 337 participants;  τ(2)=0.006), small for gestational age (1.44, 1.36 to 1.54; 51 studies, 93 191  participants; τ(2)=0.016), short for gestational age (1.47, 1.29 to 1.69; 40  studies, 83 827 participants; τ(2)=0.074), and microcephaly (1.57, 1.31 to 1.88;  31 studies, 80 046 participants; τ(2)=0.145) compared with adequate GWG.  Excessive GWG was associated with a higher risk of preterm birth (1.22, 1.13 to  1.31; 48 studies, 103 762 participants; τ(2)=0.008), large for gestational age  (1.44, 1.33 to 1.57; 47 studies, 90 044 participants; τ(2)=0.009), and macrosomia  (1.52, 1.33 to 1.73; 29 studies, 68 138 participants; τ(2)=0) compared with  adequate GWG. The direction and magnitude of the associations between GWG  adequacy and several neonatal outcomes were modified by maternal age and body  mass index before pregnancy. CONCLUSIONS: Inadequate and excessive GWG are  associated with a higher risk of adverse neonatal outcomes across settings.  Interventions to promote optimal GWG during pregnancy are likely to reduce the  burden of adverse neonatal outcomes, however further research is needed to assess  optimal ranges of GWG based on data from low and middle income countries.