Predictors of change in physical activity during and after pregnancy: Project Viva

BACKGROUND: Few studies document longitudinal changes in physical activity from prepregnancy to the postpartum period. METHODS: This study estimated change in self-reported leisure-time physical activity in 1442 women before pregnancy, during the second trimester, and at 6 months postpartum. In addition, it also examined predictors of becoming insufficiently active during or after pregnancy. RESULTS: The mean (SD) age was 32.5 (4.5) years, 34% of the women were overweight or obese prepregnancy (body mass index equal to or greater than 25 kg/m(2)), and 76% were white. Before pregnancy, the mean total leisure physical activity was 9.6 hours per week. The reported decrease in total activity between prepregnancy and 6 months postpartum was -1.4 (95% CI=-1.0 to -1.9) hours per week, accounted for by decreases in moderate and vigorous physical activity but not walking. Prevalence of insufficiently active lifestyle (less than 150 minutes per week of total activity) increased from 12.6% before pregnancy to 21.7% during the postpartum period. The OR for becoming insufficiently active during pregnancy was 1.58 (95% CI=1.07-2.32) in women with at least one child compared with no children. Predictors of becoming insufficiently active postpartum included postpartum weight retention (OR=1.31; 95% CI=1.05-1.58 for each 5-kg increment); working longer hours in the first trimester (e.g., OR=5.12; 95% CI=1.96-13.4 for 45+ vs 0 hours); and reporting that lack of child care was a barrier to physical activity (OR=1.73; 95% CI=0.99-3.02). CONCLUSIONS: Women reported decreases in moderate and vigorous physical activity during pregnancy that persisted at 6 months postpartum. Levels of walking did not decline. Children in the home, longer work hours, and lack of child care were predictors of becoming insufficiently active during or after pregnancy.     

Determinants of Excessive Gestational Weight Gain in Urban,Low-Income Women

BackgroundFactors influencing excessive weight gain in pregnancy have not been well-studied among urban, low-income women.MethodsThis prospective cohort study of 94 prenatal care patients at a large university hospital in Philadelphia examined associations of modifiable midpregnancy behaviors and nonmodifiable or early pregnancy factors with excessive gestational weight gain. Data were collected through questionnaires and medical record abstraction from 2009 to 2011.FindingsThe majority of women were African American (83%) and all (100%) received Medicaid. Nearly two thirds (60%) were overweight or obese in early pregnancy and 41% experienced excessive gain. In multivariable logistic regression analyses, significant predictors of excessive gestational weight gain included high early pregnancy body mass index (odds ratio [OR], 4.20; 95% confidence interval [CI], 1.43–12.34 for overweight/obese vs. normal weight), nulliparity (OR, 3.35; 95% CI, 1.17–9.62 for nulliparity vs. multiparity), and clinician advice discordant with Institute of Medicine guidelines (OR, 5.88; 95% CI, 1.04–33.32 for discordant vs. concordant advice). Watching under 2 hours of television daily (OR, 0.18; 95% CI, 0.03–1.03), and engaging in regular physical activity during pregnancy (OR, 0.35; 95% CI, 0.11–1.09) were suggestive of a reduced risk of excessive gain.ConclusionsIn this sample of urban, low-income women, high early pregnancy body mass index, nulliparity, and discordant clinician advice were directly associated with excessive gestational weight gain, with a trend toward decreased risk for viewing fewer hours of television and engaging in regular physical activity. Intervening on these targets may optimize gestational weight gain and promote long-term maternal health.     

Association of fewer hours of sleep at 6 months postpartum with substantial weight retention at 1 year postpartum

Shorter sleep duration is linked to obesity, coronary artery disease, and diabetes. Whether sleep deprivation during the postpartum period affects maternal postpartum weight retention remains unknown. This study examined the association of sleep at 6 months postpartum with substantial postpartum weight retention (SPPWR), defined as 5 kg or more above pregravid weight at 1 year postpartum. The authors selected 940 participants in Project Viva who enrolled during early pregnancy from 1999 to 2002. Logistic regression models estimated odds ratios of SPPWR for sleep categories, controlling for sociodemographic, prenatal, and behavioral attributes. Of the 940 women, 124 (13%) developed SPPWR. Sleep distributions were as follows: 114 (12%) women slept < or =5 hours/day, 280 (30%) slept 6 hours/day, 321 (34%) slept 7 hours/day, and 225 (24%) slept > or =8 hours/day. Adjusted odds ratios of SPPWR were 3.13 (95% confidence interval (CI): 1.42, 6.94) for < or =5 hours/day, 0.99 (95% CI: 0.50, 1.97) for 6 hours/day, and 0.94 (95% CI: 0.50, 1.78) for > or =8 hours/day versus 7 hours/day (p = 0.012). The adjusted odds ratio for SPPWR of 2.05 (95% CI: 1.11, 3.78) was twofold greater (p = 0.02) for a decrease in versus no change in sleep at 1 year postpartum. Sleeping < or =5 hours/day at 6 months postpartum was strongly associated with retaining > or =5 kg at 1 year postpartum. Interventions to prevent postpartum obesity should consider strategies to attain optimal maternal sleep duration.     

孕前体重指数、孕期体重增加与新生儿窒息的关系

目的 了解孕前体重指数(BMI)、孕期体重增加与新生儿窒息发生危险的关系.方法 数据来自"中美预防出生缺陷和残疾合作项目"中嘉兴地区的围产保健监测数据库.研究对象为1995-2000年在嘉兴地区参加婚前/孕前体检且分娩单胎活产儿孕满20周的83 030名孕产妇.运用χ2检验或趋势χ2检验比较不同BMI组或其他特征人群新生儿窒息发病率的差别,利用多元logistic回归分析孕前BMI、孕期体重增加与新生儿窒息发生危险之间的关系.结果 新生儿窒息发病率为11.3%(95% CI:11.1%～11.6%).新生儿窒息发病率从BMI＜18.5 kg/m2组的11.0%(95% CI:10.5%～11.5%)逐渐升至BMI≥25.0 kg/m2组的12.9%(95% CI:11.6%～14.4%),自孕期体重增加＜0.3 kg/wk的12.4%(95% CI:11.9%～13.0%)逐渐降至≥0.5 kg/wk的10.6%(95% CI:10.1%～11.0%).孕前BMI≥25.0 kg/m2组的新生儿重度窒息发生率高于BMI更低组.在调整了地区、年龄、文化程度、职业、产次、产前检查次数、孕期高危因素、产时高危因素、孕周和出生体重后,以BMI＜18.5 kg/m2组为参照组,BMI为18.5～22.9 kg/m2、23.0～24.9 kg/m2和≥25.0 kg/m2组发生新生儿窒息的OR值分别为1.03(95% CI:0.97～1.09)、1.06(95% CI:0.96～1.16)和1.14(95% CI:1.00～1.31).进一步调整孕期增重后,上述OR值分别为1.02(95% CI:0.95～1.09)、1.01(95% CI:0.90～1.13)和1.08(95% CI:0.92～1.28).以孕期体重增加≥0.5 kg/wk组作为参照,孕期体重增加为0.3～kg/wk和＜0.3 kg/wk组发生新生儿窒息的OR值分别为1.06(95% CI:1.01～1.12)和1.09(95% CI:1.02～1.20).结论 孕期体重增加＜0.5 kg/wk加大新生儿窒息发生的危险,提示临床上宜对妇女孕前的BMI进行监测,并据此进行孕前指导和孕期管理,以保持合理的孕期体重,降低新生儿窒息的发生危险.     

Food groups as predictors for short-term weight changes in men and women of the EPIC-Potsdam cohort

This study examined the effect of food group intake on subsequent 2-y weight change. Food-frequency questionnaire-based food intake data of 17,369 nonsmoking subjects of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort were examined in their relation to a subsequent weight change. Dietary data, collected from 1994 to 1998, were grouped into 24 food groups. Weight change per year follow-up was the outcome of interest; large weight gain was defined as > or =2 kg; small weight gain as > or =1 kg to <2 kg; large weight loss as < or = -2 kg; small weight loss as < or = -1 kg to > -2 kg and weight maintenance as +/- 1 kg. For each food group, a separate polytomous logistic regression model with stable weight as the reference group was constructed, controlling for age, body mass index, previous weight change, and behavioral and lifestyle factors. Odds ratios (OR) and 95% confidence intervals (CI) estimated the increase in risk associated with each 100 g/d increment in food group intake. In women, consumption of high energy, high fat food groups significantly predicted large weight gain, e.g., fats (OR = 1.75; 95% CI, 1.01-3.06), sauces (OR = 2.12; 95% CI, 1.17-3.82) and meat (OR = 1.36; 95% CI, 1.04-1.79), and the consumption of cereals predicted large weight loss (OR = 1.43; 95% CI, 1.09-1.88). In men, intake of high energy, high sugar foods, i.e., sweets, was significantly predictive of large weight gain (OR = 1.48; 95% CI, 1.03-2.13). Our data show that a diet rich in high fat and high energy foods predicts short-term weight gain even if controlled for many potential confounding factors.     

Postpartum weight retention among women in Rio de Janeiro: a follow-up study

This study presents follow-up results on trends in postpartum weight retention among women in the city of Rio de Janeiro, Brazil, at 0.5, 2, 6, and 9 months postpartum. The outcome variable, weight retention, was calculated by subtracting the reported pre-pregnancy weight from the observed weight at each interview. Statistical analyses used means and a 95% confidence interval for weight retention. Mean weight retention was 4.7, 4.1, 3.4, and 3.1kg at 0.5, 2, 6 and 9 months postpartum, respectively. At completion of the study, the largest weight retention was observed in women over 30 years of age (4.2kg) and with 30% or more of body fat (5.9kg). The rate of reduction in weight retention was 0.4kg/month, 0.2kg/month, and 0.1kg/ month for the periods 0.5-2, 2-6, and 6-9 months, respectively. The largest reductions were observed among young, single women and those with < 30% of body fat at baseline. The results suggest that variables such as age, parity, schooling, and body fat may be important predictors of postpartum weight retention.     

Postpartum Weight Change in Relation to Pre-Pregnancy Weight and Gestational Weight Gain in Women in Low-Income Setting: Data from the KITE Cohort in the Northern Part of Ethiopia

(1) Background: Postpartum weight may increase compared to pre-pregnancy due to weight retention or decrease due to weight loss. Both changes could pose deleterious effects on maternal health and subsequent pregnancy outcomes. Therefore, this study aimed to assess postpartum weight change and its associated factors. (2) Methods: A total of 585 women from the KIlte-Awlaelo Tigray Ethiopia (KITE) cohort were included in the analysis. (3) Results: The mean pre-pregnancy body mass index and weight gain during pregnancy were 19.7 kg/m² and 10.8 kg, respectively. At 18 to 24 months postpartum, the weight change ranged from −3.2 to 5.5 kg (mean = 0.42 kg [SD = 1.5]). In addition, 17.8% of women shifted to normal weight and 5.1% to underweight compared to the pre-pregnancy period. A unit increase in weight during pregnancy was associated with higher weight change (β = 0.56 kg, 95% CI [0.52, 0.60]) and increased probability to achieve normal weight (AOR = 1.65, 95% CI [1.37, 2.00]). Food insecurity (AOR = 5.26, 95% CI [1.68, 16.50]), however, was associated with a shift to underweight postpartum. Interestingly, high symptoms of distress (AOR = 0.13, 95% CI [0.03, 0.48]) also negatively impacted a change in weight category. (4) Conclusions: In low-income settings such as northern Ethiopia, higher weight gain and better mental health during pregnancy may help women achieve a better nutritional status after pregnancy and before a possible subsequent pregnancy.     

Changes in caffeine intake and long-term weight change in men and women

BACKGROUND: The long-term effects of caffeine intake on weight have not been examined prospectively. OBJECTIVE: The objective was to assess the relation between caffeine intake and 12-y weight change. DESIGN: We conducted a prospective study of 18 417 men and 39 740 women, with no chronic diseases at baseline, who were followed from 1986 to 1998. Caffeine intake was assessed repeatedly every 2-4 y. Weight change was calculated as the difference between the self-reported weight in 1986 and in 1998. RESULTS: The participants reported a change in caffeine intake that varied across quintiles, from decreases of 296 and 342 mg/d to increases of 213 and 143 mg/d in men and women, respectively. Age-adjusted models showed a lower mean weight gain in participants who increased their caffeine consumption than in those who decreased their consumption, but the differences between extreme quintiles were small: -0.43 kg (95% CI: -0.17, -0.69) in men and -0.41 kg (95% CI: -0.20, -0.62) in women. After adjustment for potential confounders and baseline and change in total energy intake and other nutrients and foods, the differences remained similar for men and diminished slightly for women (men: -0.43 kg; 95% CI: -0.17, -0.68; women: -0.35; 95% CI: -0.14, -0.56). An increase in coffee and tea consumption was also associated with less weight gain. In men, the association between caffeine intake and weight was stronger in younger participants (P for interaction < 0.001); in women, the association was stronger in those who had a body mass index (in kg/m2) > or = 25, who were less physically active, or who were current smokers (P for interaction < 0.001). CONCLUSION: Increases in caffeine intake may lead to a small reduction in long-term weight gain.     

Gestational weight gain and prepregnancy weight influence postpartum weight retention in a cohort of brazilian women

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.     

Breastfeeding and postpartum weight retention in a cohort of Brazilian women

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.     

Postpartum weight retention in relation to gestational weight gain and pre-pregnancy body mass index: A prospective cohort study in Vietnam

BackgroundThe prevalence of maternal overweight and obesity is increasing in Asia. This study prospectively investigated the association between pre-pregnancy body mass index (BMI), gestational weight gain (GWG) and 12-month postpartum weight retention (PPWR) in a large cohort of Vietnamese mothers.MethodsOf the 2030 pregnant women recruited from three cities in Vietnam at 24–28 weeks of gestation, a total of 1666 mothers were followed up for 12 months after delivery and available for analysis. The outcome variable PPWR was determined by subtracting the pre-pregnancy weight from the 12-month postpartum measured weight, while GWG and pre-pregnancy BMI were classified according to the Institute of Medicine and WHO criteria for adults, respectively. Linear regression models were used to ascertain the association between pre-pregnancy BMI, GWG and PPWR accounting for the effects of plausible confounding factors.ResultsBoth pre-pregnancy BMI and GWG were significantly associated with PPWR (P < 0.001). The adjusted mean weight retention in underweight women before pregnancy (3.71 kg, 95% confidence interval (CI) 3.37–4.05) was significantly higher than that in those with normal pre-pregnancy weight (2.34 kg, 95% CI 2.13–2.54). Women with excessive GWG retained significantly more weight (5.07 kg, 95% CI 4.63–5.50) on average at 12 months, when compared to mothers with adequate GWG (2.92 kg, 95% CI 2.67–3.17).ConclusionsBeing underweight before pregnancy and excessive GWG contribute to greater weight retention twelve months after giving birth. Interventions to prevent postpartum maternal obesity should target at risk women at the first antenatal visit and control their weight gain during the course of pregnancy.     

Association between dairy food consumption and weight change over 9 y in 19,352 perimenopausal women

BACKGROUND: Dairy foods may play a role in the regulation of body weight. OBJECTIVE: We examined the association between changes in dairy product consumption and weight change over 9 y. DESIGN: The study was conducted in 19 352 Swedish women aged 40-55 y at baseline. Data on dietary intake, body weight, height, age, education, and parity were collected in 1987-1990 and 1997. The intake frequencies of whole milk and sour milk (3% fat), medium-fat milk (1.5% fat), low-fat milk and sour milk (or=1 serving/d; 3) constant, >or=1 serving/d; and 4) decreased from >or=1 serving/d to <1 serving/d. Odds ratios (ORs) with 95% CIs for an average weight gain of >or=1 kg/y were calculated by using multivariable logistic regression analyses, with group 1 as the reference. RESULTS: Mean (+/-SD) body mass index (in kg/m2) at baseline was 23.7 +/- 3.5. The constant (>or=1 serving/d) intakes of whole milk and sour milk and of cheese were inversely associated with weight gain; ORs for group 3 were 0.85 (95% CI: 0.73, 0.99) and 0.70 (95% CI: 0.59, 0.84) respectively. No significant associations were seen for the other 3 intake groups. When stratified by BMI, the findings remained significant for cheese and, for normal-weight women only, for whole milk and sour milk. CONCLUSION: The association between the intake of dairy products and weight change differed according to type of dairy product and body mass status. The mechanism behind these findings warrants further investigation.     

Association between reduced sleep and weight gain in women

Physiologic studies suggest that sleep restriction has metabolic effects that predispose to weight gain. The authors investigated the association between self-reported usual sleep duration and subsequent weight gain in the Nurses' Health Study. The 68,183 women who reported habitual sleep duration in 1986 were followed for 16 years. In analyses adjusted for age and body mass index, women sleeping 5 hours or less gained 1.14 kg (95% confidence interval (CI): 0.49, 1.79) more than did those sleeping 7 hours over 16 years, and women sleeping 6 hours gained 0.71 kg (95% CI: 0.41, 1.00) more. The relative risks of a 15-kg weight gain were 1.32 (95% CI: 1.19, 1.47) and 1.12 (95% CI: 1.06, 1.19) for those sleeping 5 and 6 hours, respectively. The relative risks for incident obesity (body mass index: >30 kg/m(2)) were 1.15 (95% CI: 1.04, 1.26) and 1.06 (95% CI: 1.01, 1.11). These associations remained significant after inclusion of important covariates and were not affected by adjustment for physical activity or dietary consumption. These data suggest that short sleep duration is associated with a modest increase in future weight gain and incident obesity. Further research is needed to understand the mechanisms by which sleep duration may affect weight.     

The contribution of psychosocial and home environmental factors in explaining eating behaviours in adolescents

OBJECTIVE: The present study aimed at investigating the influence of food availability, rules and television viewing habits on eating behaviours in adolescents. DESIGN: Cross-sectional study. SETTING: Four randomly selected middle schools. SUBJECTS: A sample of 534 seventh and eighth graders. INTERVENTIONS: Validated questionnaires were used to measure the family environment and fat, soft drink and fruit consumption. Hierarchical regression analyses on fat, soft drink and fruit consumption, with demographic and psychosocial variables entered as the first and environmental factors as the second block were conducted in boys and girls. RESULTS: Boys with more unhealthy products available at home consumed more fat (P< or =0.001, 95% CI: 8.2-29.4) and more soft drinks (P< or =0.01, 95% CI: 0.2-1.4). Boys who reported better television viewing habits ate more fruit (P< or =0.001, 95% CI: -1.7 to -0.5). Girls who reported better television viewing habits consumed less fat (P< or =0.01, 95% CI: 1.4-9.0) and more fruit (P< or =0.05, 95% CI: -1.0 to -0.1). Girls who reported higher availability of healthy products at home (P< or =0.05, 95% CI: 0.3-3.1) and more food rules (P< or =0.001, 95% CI: -1.8 to -0.5), consumed more fruit. Environmental factors were poor predictors of soft drink consumption among girls. CONCLUSION: Availability of (un)healthy food products, family food rules and TV viewing habits were related to one or more eating behaviours in boys or girls. Although home environmental factors can play an important role in influencing adolescents' eating behaviours, these factors were generally less predictive than demographic and psychosocial variables.     

Prospective study of dietary energy density and weight gain in women

BACKGROUND: Little is known about the long-term effects of dietary energy density (ED) on weight gain. OBJECTIVE: The objective was to assess the long-term relation between changes in dietary ED and age-related weight gain. DESIGN: We conducted a prospective study of 50 026 women (x +/- SD age: 36.5 +/- 4.6 y) in the Nurses' Health Study II followed from 1991 to 1999. Dietary ED and body weight were ascertained in 1991, 1995, and 1999. Total dietary ED was calculated by dividing each subject's daily energy intake (kcal) by the reported weight (g) of all foods consumed. RESULTS: Dietary ED was positively correlated with saturated fat (r = 0.16), trans fat (r = 0.15), and the glycemic index (r = 0.16), but was inversely correlated with vegetable protein (r = -0.30), vegetables (r = -0.27), and fruit (r = -0.17). ED was not significantly correlated with total fat intake as a percentage of energy (r = 0.08). Women who increased their dietary ED during follow-up the most (5th quintile) had a significantly greater multivariate-adjusted weight gain than did those who decreased their dietary ED (1st quintile) (8-y time period: 6.42 kg compared with 4.57 kg; P for trend < 0.001). However, the amount of weight change over time varied considerably according to the ED values of individual foods and beverages. CONCLUSION: A high dietary ED reflects a dietary pattern higher in saturated and trans fats and refined carbohydrates. Increases in dietary ED were associated with greater weight gain among middle-aged women during 8 y of follow-up. However, public health recommendations cannot be made simply on the basis of ED values of individual foods and beverages.     

Physical activity and changes in weight and waist circumference in midlife women: findings from the Study of Women's Health Across the Nation

Controversy exists regarding the extent to which age, menopausal status, and/or lifestyle behaviors account for the increased weight, fat mass, and central adiposity experienced by midlife women. To address this question, the authors longitudinally examined the relations of aging, menopausal status, and physical activity to weight and waist circumference in 3,064 racially/ethnically diverse women aged 42-52 years at baseline who were participating in the Study of Women's Health Across the Nation (SWAN), an observational study of the menopausal transition. Over 3 years of follow-up (1996-1997 to 1999-2000), mean weight increased by 2.1 kg (standard deviation (SD), 4.8) or 3.0% (SD, 6.5) and mean waist circumference increased by 2.2 cm (SD, 5.4) or 2.8% (SD, 6.3). Change in menopausal status was not associated with weight gain or significantly associated with increases in waist circumference. A one-unit increase in reported level of sports/exercise (on a scale of 1-5) was longitudinally related to decreases of 0.32 kg in weight (p < 0.0001) and 0.10 cm in waist circumference (not significant). Similar inverse relations were observed for daily routine physical activity (biking and walking for transportation and less television viewing). These findings suggest that, although midlife women tend to experience increases in weight and waist circumference over time, maintaining or increasing participation in regular physical activity contributes to prevention or attenuation of those gains.     

Gestational Weight Gain and Postpartum Weight Retention in a Cohort of Nova Scotian Women

Excess gestational weight gain (GWG) may predispose mothers to becoming overweight or obese. The aim of this study was to investigate the association between GWG, according to the American Institute of Medicine (IOM) guidelines, and postpartum weight retention (PPWR). A cohort of 12,875 women from Nova Scotia, Canada with at least two consecutively recorded pregnancies was identified through a population-based perinatal database between 1993 and 2010. GWG was calculated as the difference between delivery and prepregnancy weights. PPWR, analyzed as a continuous variable in linear regression models, was calculated via interpregnancy weight change. Fifty eight percent of the total study population gained in excess of the IOM guidelines. Mean PPWR, adjusted for age and prepregnancy body mass index (BMI) among women with excess GWG was 5.0 kg (95 % CI 4.9–5.2), greater than women with adequate (2.1 kg, 95 % CI 1.8–2.3) or inadequate GWG (0.3 kg, 95 % CI 0–0.7). Effect modification by prepregnancy BMI was observed; the relationship between excess GWG and increased PPWR was observed in all prepregnancy BMI categories, yet was greatest among underweight women (7.5 kg, 95 % CI 6.6–8.3). Effect modification by parity was also observed; in contrast to multiparous women, primiparous women who gained in excess of GWG guidelines retained more postpartum weight (5.3 kg, 95 % CI 5.1–5.5 vs. 4.3 kg, 95 % CI 4.0–4.7). This study demonstrates that excess GWG is associated with an increase in the amount of weight retained after pregnancy. Interventions targeted to promote optimal GWG are warranted.     

Dietary Fat and Protein Intake Are Not Associated With Incident Biliary Sludge and Stones During Pregnancy

Background: Dietary composition can cause insulin resistance, elevated serum lipid levels, and obesity, all of which predispose to gallstone formation. The effects of dietary fat (including individual fatty acids) and protein on gallstone formation are controversial. The aim of this study was to examine the effects of dietary fat and protein intake on incident gallstone disease during pregnancy, a high‐risk time for stone formation. Methods: We prospectively studied 3070 pregnant women who underwent serial gallbladder ultrasound examinations during pregnancy and at 4–6 weeks postpartum. All women had at least 2 study ultrasounds for comparison. A semi‐quantitative food frequency questionnaire was completed by subjects in the early third trimester. Multivariate logistic regression was performed to assess the risk of incident gallbladder disease across quartiles of intake of total fat, individual fatty acids (polyunsaturated, monounsaturated, saturated, and total trans‐fatty acids, as well as cholesterol), protein, and protein subtype (animal or vegetable based). Results: The cumulative incidence of new biliary sludge/stones or progression of baseline sludge to stones was 10.2% by 4–6 weeks postpartum. There was no association between total dietary fat (odds ratio [OR], 1.18; 95% confidence interval [CI], 0.64–2.18 comparing lowest and highest quartiles) or protein intake (OR, 0.83; 95% CI, 0.44–1.22 comparing lowest and highest quartiles) and incident gallbladder disease. There was also no association between individual fatty acids or protein subtype and gallbladder disease. Conclusions: Neither total nor subtype of dietary fat or protein was associated with incident biliary stone or sludge formation in this cohort of pregnant women.     

Children's food consumption during television viewing

BACKGROUND: Television viewing is associated with childhood obesity. Eating during viewing and eating highly advertised foods are 2 of the hypothesized mechanisms through which television is thought to affect children's weight. OBJECTIVES: Our objectives were to describe the amounts and types of foods that children consume while watching television, compare those types with the types consumed at other times of the day, and examine the associations between children's body mass index (BMI) and the amounts and types of foods consumed during television viewing. DESIGN: Data were collected from 2 samples. The first sample consisted of ethnically diverse third-grade children, and the second consisted predominantly of Latino fifth-grade children. Three nonconsecutive 24-h dietary recalls were collected from each child. For each eating episode reported, children were asked whether they had been watching television. Height and weight were measured by using standard methods and were used to calculate BMI. RESULTS: On weekdays and weekend days, 17-18% and approximately 26% of total daily energy, respectively, were consumed during television viewing in the 2 samples. Although the fat content of the foods consumed during television viewing did not differ significantly from that of the foods consumed with the television off, less soda, fast food, fruit, and vegetables were consumed with the television on. The amount of food consumed during television viewing was not associated with children's BMI, but in the third-grade sample, the fat content of foods consumed during television viewing was associated with BMI. CONCLUSIONS: A significant proportion of children's daily energy intake is consumed during television viewing, and the consumption of high-fat foods on weekends may be associated with BMI in younger children.     

孕期增重以及产后软饮料的摄入对产后体重滞留的影响

目的 研究孕期增重以及产后膳食对产后体重滞留的影响 方法 采用队列研究的方法,以在北京北方医院进行产后复查的产妇为研究对象,分别在产后1个月、6个月进行追踪随访,调查研究对象的一般信息、孕前、分娩前、产后1个月、6个月的体重;用半定量的食物频数法,收集研究对象的膳食摄入信息。利用多元线性回归模型,分析孕期增重以及膳食摄入量与产后体重滞留的关系。结果 孕期增重（β = 0.73, 95%CI: 0.52～0.71,β = 0.67, 95%CI: 0.51～0.77）、软饮料摄入量（β = 0.14, 95%CI: 0.14～1.34,β = 0.15, 95%CI: 0.05～1.53）与产后1、6个月体重滞留呈正相关关系,关联具有统计学意义;按照喂养方式分层后,孕期增重、软饮料摄入与产后1个月、6个月喂养方式之间不存在交互作用。结论 孕期增重与产后软饮料摄入与产后体重滞留有关,与软饮料摄入量相比,孕期增重是产后体重滞留更重要的预测因子。