ABSTRACT
OBJECTIVE: To identify factors potentially associated with weight retention measured 9 months after childbirth. DESIGN: Prospective study with four follow-up waves in time (0.5, 2, 6 and 9 months postpartum). SETTING: Rio de Janeiro, Brazil. SUBJECTS AND METHODS: Two hundred and sixty-six Brazilian women of childbearing age. Analysis was based on hierarchical logistic regression. The dependent variable was weight retention and was defined as the difference between weight at 9 months postpartum and pre-pregnancy weight, with a dichotomised cut-off at 7.5 kg. Covariates included demographic and socio-economic data, obstetric history, anthropometric data, and data on the infant. These data were grouped in blocks and ordered according to their influence on the dependent variable. RESULTS: Of the women studied, 19.2% presented weight retention values > or =7.5 kg. According to the logistic regression analysis, the following variables remained associated with weight retention > or =7.5 kg: total family income, difficulty or inability to read a letter, age category > or =30 years, age at first childbirth <23 years, gestational weight gain > or =12 kg, body fat at baseline > or =30% and infant birth weight <3500 g. Infant hospitalisation was only marginally significant. CONCLUSIONS: Determinant factors identified by the analysis highlight the need for nutritional intervention policies during pregnancy and in the first months postpartum as a way of minimising obesity and the diseases resulting from it.
Subject(s)
Obesity/epidemiology , Postpartum Period/physiology , Weight Gain/physiology , Adolescent , Adult , Age Factors , Body Composition/physiology , Body Mass Index , Body Weight/physiology , Brazil/epidemiology , Causality , Cohort Studies , Female , Follow-Up Studies , Humans , Logistic Models , Middle Aged , Odds Ratio , Predictive Value of Tests , Prospective Studies , Socioeconomic FactorsABSTRACT
BACKGROUND: The relation between postpartum weight retention and breastfeeding practices is controversial. OBJECTIVE: Defining breastfeeding as the period when a child is exclusively or predominantly breastfed, we studied the association between breastfeeding duration and postpartum weight retention. DESIGN: We followed 405 women aged 18-45 y who were assessed at 0.5, 2, 6, and 9 mo postpartum. The outcome variable, postpartum weight retention, was expressed as the difference between the observed weight at each follow-up and the reported prepregnancy weight. The main statistical procedure used was the longitudinal mixed-effects model. RESULTS: Mean postpartum weight retention at the end of the study was 3.1 kg. Single women aged > or = 30 y retained more weight than did younger single women or married women. The combined effect of breastfeeding duration and percentage of body fat at baseline was significant only for women with < 30% body fat. According to the model's prediction, when women who had 22% body fat and breastfed for 180 d were compared with those who had 22% body fat and breastfed for only 30 d, each month of breastfeeding contributed -0.44 kg to postpartum weight retention. When only the percentage of body fat was varied, the total effect was 3.0, 1.7, 1.2, and 0.04 kg in women with 18%, 25%, 28%, and 35% body fat, respectively. CONCLUSIONS: These results support the hypothesis of an association between breastfeeding and postpartum weight retention and suggest that encouraging prolonged breastfeeding might contribute to decreases in postpartum weight retention.
Subject(s)
Body Weight/physiology , Breast Feeding , Lactation/physiology , Postpartum Period/physiology , Adolescent , Adult , Age Factors , Brazil , Cohort Studies , Female , Follow-Up Studies , Humans , Middle Aged , Postnatal Care , Pregnancy , Risk Factors , Time Factors , Weight LossABSTRACT
The objective of the study was to test the association between gestational weight gain, reproductive factors, and postpartum weight retention based on a cohort conducted with 405 women aged 18-45 y with follow-up waves at 0.5, 2, 6, and 9 mo postpartum. The outcome variable, postpartum weight retention, was calculated as the difference between the measured weight at each visit minus the prepregnancy weight. We estimated the statistical associations between the outcome variable and potential explanatory covariates of interest by fitting a longitudinal mixed-effects model. Women with gestational weight gain above the recommendations of the Institute of Medicine (IOM) retained significantly more weight than women with weight gain within or below the recommendations, independently of prepregnancy BMI [weight (kg)/height (m(2))] or body fat at baseline. Women with the highest gestational weight gain and with body fat >/=30 g/100 g at baseline had the highest likelihood of developing maternal obesity. The final longitudinal model showed that 35% of each kilogram of weight gained during pregnancy was retained 9 mo postpartum, even after adjustment for age, prepregnancy BMI, body fat at baseline, and years since first parturition. Each unit of increase in prepregnancy BMI was associated with a decrease of -0.51 kg in postpartum weight retention. In conclusion, gestational weight gain was one of the most important predictors for postpartum weight retention and must be monitored systematically with the aim of preventing postpartum obesity and the diseases that follow.
