Effectiveness of a normative nutrition intervention in Chilean pregnant women on maternal and neonatal outcomes: the CHiMINCs study

Abstract

ABSTRACT Background Some nutritional interventions have shown their efficacy in reducing gestational weight gain (GWG); however, their applicability in routine care is limited. Objective We assessed the effectiveness of a low-intensity and high-coverage nutritional intervention on maternal and offspring outcomes; the intervention enhanced existing nutritional health care standards and practices at the primary health care level in Chile. Methods This study was a cluster-randomized controlled trial of 12 primary health care centers (PHCCs) from Santiago, Chile. PHCCs were randomly allocated to either nutritional intervention [intervention group (IG), n = 5] or routine care [control group (CG), n = 7]. A total of 4631 pregnant women were recruited (IG, n = 2565; and CG, n = 2066). Primary outcomes were adequate GWG and glycemic control in mothers and birth weight, birth length, macrosomia, and large for gestational age in neonates. The intervention consisted of 4 key actions: training of health care professionals on nutritional recommendations, counseling of pregnant women on diet and physical activity recommendations, offering a physical activity program implemented in the participating PHCCs, and adequate referral to dietitians. Women randomly assigned to the CG received routine antenatal care. Results At baseline, the mean age was 26.1 y; 45% of women were primipara and 24% were obese. No differences were found in the percentage of women achieving adequate GWG (IG: 30.3%, compared with CG: 31.3%; OR: 0.94; 95% CI: 0.81, 1.09), but women in the IG had lower GWG than those in the CG (11.3 compared with 11.9 kg; mean difference: −0.63 kg; 95% CI: −1.19, −0.08). Effects of the intervention were significantly higher in women with obesity at the begining of pregnancy (mean difference: −1.24 kg; 95% CI: −2.18, −0.30; P for interaction < 0.05). No differences were found between groups regarding maternal glycemic control or neonatal outcomes. Conclusions Our findings demonstrate that a low-intensity, high-coverage intervention delivered through the Chilean public health care system under standard operating conditions reduces GWG and has the potential for successful scale-up. This trial was registered at clinicaltrials.gov as NCT01916603.