Breastfeeding and maternal weight changes during 24 months post-partum: a cohort study.

The relationship between breastfeeding and the loss of weight gained during pregnancy remains unclear. This study aimed to investigate the association between breastfeeding and maternal weight changes during 24 months post-partum. We studied a dynamic cohort comprising 315 women living in two cities in the state of Bahia, Brazil. The outcome variable was change in the post-partum weight; the exposure variable was the duration and intensity of breastfeeding. Demographic, socio-economic, environmental, reproductive and lifestyle factors were integrated in the analysis as covariates. The data were analysed using multiple linear regression and linear mixed-effects models. The average cumulative weight loss at 6 months post-partum was 2.561 kg (SD 4.585), increasing at 12 months (3.066 kg; SD 5.098) and decreasing at 18 months (1.993 kg; SD 5.340), being 1.353 kg (SD, 5.574) at 24 months post-partum. After adjustment, the data indicated that for every 1-point increase in breastfeeding score, the estimated average post-partum weight loss observed was 0.191 kg at 6 months (P = 0.03), 0.090 kg at 12 months (P = 0.043), 0.123 kg at 18 months (P < 0.001) and 0.077 kg at 24 months (P = 0.001). Based on these results, we concluded that despite the low expressiveness, the intensity and duration of breastfeeding was associated with post-partum weight loss at all stages of the study during the 24-month follow-up.

Predictors of linear growth in the first year of life of a prospective cohort of full term children with normal birth weight.

OBJECTIVE: To investigate covariates that could affect the variation in mean length/age z scores in the first year of life of children born full term with normal birth weight. METHODS: This was a prospective study of a cohort of mother-infant pairs recruited at public maternity units in two municipalities in the Brazilian state of Bahia, from March 2005 to October 2006. This paper reports the results for linear growth of 489 children who were followed-up for the first 12 months of their lives. A mixed-effect regression model was used to investigate the influence of covariates of mean length/age z score during the first year of life. RESULTS: The multivariate mixed effect analysis indicated that mothers not cohabiting with a partner (beta = 0.2347; p = 0.004) and increased duration of exclusive breastfeeding (beta = 0.0031; p < 0.001) had a positive impact, whereas mother's height less than 150 cm (beta = -0.4393; p < 0.001), birth weight of 2,500-2,999 g (beta = -0.8084; p < 0.001) and anemia in the child (beta = -0.0875; p < 0.001) all had a negative impact on the variation in estimated length/age z score. CONCLUSIONS: Therefore, the results of this study indicate that short maternal stature, birth weight < 3,000 g and anemia in the infant had a negative effect on linear growth during the first year of life, whereas longer duration of exclusive breastfeeding and mothers who did not cohabit with a partner had a positive effect.

Preditores do crescimento linear no primeiro ano de vida em uma coorte prospectiva de crianças a termo com peso adequado / Predictors of linear growth in the first year of life of a prospective cohort of full term children with normal birth weight

OBJETIVO: Investigar covariáveis que possam interferir na variação da média do índice comprimento/idade em escore Z no primeiro ano de vida de crianças nascidas a termo com peso adequado. MÉTODOS: Trata-se de um estudo de coorte prospectivo, envolvendo pares de mães e crianças recrutadas nas maternidades públicas de dois municípios do estado da Bahia, entre março de 2005 e outubro de 2006. Neste estudo, apresentam-se os resultados para o crescimento linear de 489 crianças acompanhadas durante os primeiros 12 meses de vida. O modelo de efeitos mistos foi utilizado para explorar a influência de covariáveis na média do índice comprimento/idade em escore Z no primeiro ano de vida. RESULTADOS: Na análise múltipla de efeito misto, observou-se que ausência de coabitação materna com companheiro (β = 0,2347; p = 0,004) e maior tempo de aleitamento materno exclusivo (β = 0,0031; p < 0,001) contribuíram positivamente, enquanto a altura materna menor do que 150 cm (β = -0,4393; p < 0,001), peso ao nascer entre 2.500-2.999 g (β = -0,8084; p < 0,001) e a anemia na criança (β = -0,0875; p < 0,001) contribuíram de forma negativa na variação das estimativas do índice comprimento/idade em escore Z. CONCLUSÕES: Assim, os resultados deste estudo indicam que a baixa estatura materna, o peso de nascimento < 3.000 g e a anemia influenciaram negativamente o crescimento linear no primeiro ano de vida, enquanto a maior duração do aleitamento materno exclusivo e a ausência de coabitação materna com companheiro exerceram influência positiva.

OBJECTIVE: To investigate covariates that could affect the variation in mean length/age z scores in the first year of life of children born full term with normal birth weight. METHODS: This was a prospective study of a cohort of mother-infant pairs recruited at public maternity units in two municipalities in the Brazilian state of Bahia, from March 2005 to October 2006. This paper reports the results for linear growth of 489 children who were followed-up for the first 12 months of their lives. A mixed-effect regression model was used to investigate the influence of covariates of mean length/age z score during the first year of life. RESULTS: The multivariate mixed effect analysis indicated that mothers not cohabiting with a partner (β = 0.2347; p = 0.004) and increased duration of exclusive breastfeeding (β = 0.0031; p < 0.001) had a positive impact, whereas mother’s height less than 150 cm (β = -0.4393; p < 0.001), birth weight of 2,500-2,999 g (β = -0.8084; p < 0.001) and anemia in the child (β = -0.0875; p < 0.001) all had a negative impact on the variation in estimated length/age z score. CONCLUSIONS: Therefore, the results of this study indicate that short maternal stature, birth weight < 3,000 g and anemia in the infant had a negative effect on linear growth during the first year of life, whereas longer duration exclusive breastfeeding and mothers who did not cohabit with a partner had a positive effect.