RESUMEN
OBJECTIVES: Our aim in this study was to evaluate breastfeeding up to 1 year postpartum and factors related to weaning in women with recent gestational diabetes mellitus (GDM). METHODS: We assembled a cohort study of women with GDM enrolled in prenatal clinics of the Brazilian National Health System as possible candidates for the Lifestyle Intervention for Diabetes Prevention After Pregnancy (LINDA-Brasil) postpartum trial (N=2,220). Sociodemographics and clinical and nutritional information, including breastfeeding, were obtained by interview or chart review. Follow-up by telephone was done at specific intervals during the first year postpartum. RESULTS: The probability of breastfeeding at 1 year postpartum, estimated from Kaplan-Meier survival analysis, was 53.5%. Cox regression models showed increased risk of weaning for those introducing milk or formula before 6 months (hazard ratio [HR], 2.55; 95% confidence interval [CI], 2.10 to 3.09); reporting problems in breastfeeding (HR, 1.49; 95% CI, 1.22 to 1.82); being Caucasian (HR, 1.46; 95% CI, 1.21 to 1.76); smoking during pregnancy (HR, 1.68; 95% CI, 1.28 to 2.20); and living in 2 southern cities of Brazil (HR, 1.58; 95% CI, 1.16 to 2.16; and HR, 1.76; 95% CI, 1.20 to 2.58). CONCLUSIONS: About half of the women with GDM ceased breastfeeding before 1 year postpartum, a rate matching that of the general population in Brazil. The main risk factor was not exclusively breastfeeding up to 6 months. Given the possibility of curbing diabetes risk by maintaining longer breastfeeding, further promotion of exclusive breastfeeding up to 6 months for these high-risk women is much needed.