Gestational Weight Gain and Prepregnancy Weight Influence Postpartum Weight Retention in a Cohort of Brazilian Women

Abstract

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.

The association of pregnancy and the development of obesity – results of a systematic review and meta-analysis on the natural history of postpartum weight retention

“…Most studies included primarily adult women. 23,[27][28][29][31][32][33]35,36,38,43,46 Four studies reported a mean age above 30 years, 23,27,28,36,46 one study below 20 years. 42 Two studies did not provide any information on their population's age 24,44 (Table 1).…”

“…Tables 1-3 summarize the results of the qualitative analysis. Fifteen prospective studies, 23,24,[29][30][31][32][33][34][35][36]38,[40][41][42][43][44][45] five retrospective studies, 22,[25][26][27][28]37,46 and the control group from a randomized controlled trial 39 were included in the final analysis. Studies in which women were recruited around the time of delivery and then followed prospectively for postpartum body weight (ambivalent design, as baseline weight was assessed retrospectively) 24,29,30,[34][35][36][44][45][46] were considered as prospective in design, as we wanted to focus on the development of postpartum weight change.…”

“…39 In developing countries, women retain less weight after pregnancy compared with women in developed countries. Two studies were conducted in Brazil [31][32][33] and China. 44 Although these studies included different populations, they did not compromise overall homogeneity as the Brazilian study reported mean reduction rates in weight retention similar to European studies.…”

“…44 Although these studies included different populations, they did not compromise overall homogeneity as the Brazilian study reported mean reduction rates in weight retention similar to European studies. [25][26][27][28][31][32][33][34]36,41,43 The study participants in the study conducted in China recruited middle class women. 44 (Table 1) All but one 34 study were published in English language.…”

“…[22][23][24][25][26][27][28][29][30][31][32][33][35][36][37][38][39][40][41][42][43][44][45][46] The study populations were mainly recruited from inpatients in departments of obstetrics. [24][25][26][31][32][33]35,36,[38][39][40][41][42][43][44][45][46] There was a higher percentage of low-income women in the studies conducted in North America, but socio-economic status was thought to be homogeneous across studies. 35,37,39,42,45,46 The sample size varied between 47 and 1423 women.…”