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. Design This study was a cluster-randomized controlled trial of twelve 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 4,631 pregnant women were recruited (IG n=2,565 and CG n=2,066). 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; offer of a physical activity program implemented in the participating PHCCs; and adequate referral to dietitians. Women randomized to the CG received routine antenatal care. Results At baseline, the mean age was 26.1 years; 45% were primipara and 24% were obese. No differences were found in the percent of women achieving adequate GWG (IG=30.3% versus CG=31.3%,OR=0.94 [0.81,1.09]), but women in the IG had lower GWG than did those in the CG (11.3 versus 11.9 kg, mean difference=-0.63 kg [-1.19,-0.08]). Effects of the intervention were significantly higher in women with obesity at the begining of pregnancy (-1.24 kg [-2.18,-0.30] p-for-interaction<0.05). No differences were 76 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, having the potential for successful scale-up. (Clinicaltrials.gov, number NCT01916603).