Comparison of Dietary Intake of Overweight Postpartum Mothers Practicing Breastfeeding or Formula Feeding

Background: Weight gain in the postpartum period is a risk factor for long-term obesity. Investigations of dietary intake among lactating and non-lactating, overweight women may identify nutritional concerns specific to this population. Objective: To compare nutrient, meal and snack intakes, food group servings and prevalence of dieting among fully breastfeeding (BF) mixed breast and formula feeding (MF), and formula feeding (FF), overweight and obese women. The second aim was to compare nutrient intakes and food group servings to the Dietary Reference Intake (DRI) and MyPyramid recommendations, respectively. Design: Data were collected from September 2004 through April 2006 in Durham, NC. Infant feeding practices and dietary information were collected on 450 women between six and nine weeks postpartum. Two 24-hour dietary recalls were completed by phone, using Nutrition Data Systems for Research. Analysis of covariance was used to compare infant feeding groups in dietary quality (nutrient intake per 1000 kcal) and food group servings, controlling for pre-pregnancy body mass index, race, age, education, income, and marital status. Chi-squared (X 2) analysis was performed to determine differences in meal and snack intake and dieting among infant feeding groups. Results: BF women consumed more energy (2107 ± 50 kcal) than MF (1866 ± 56 kcal) or FF (1657 ± 50 kcal), p<0.001. Adjusted nutrient intake did not differ between groups. All groups were at risk for inadequate intakes of vitamins A, E, C, and folate and did not meet recommended servings of all food groups. BF women consumed lunch and snacks more frequently, were less likely to diet and reported higher intakes of grains and desserts than MF and FF women. Conclusions: To help increase intakes of nutrients lacking in the diet and prevent postpartum weight gain, overweight women should be encouraged to increase fruits, vegetables, low-fat dairy, whole grains, legumes, and healthy types of fat, while decreasing refined grains, regular soda, sweetened beverages, and desserts

Active Mothers Postpartum: A Randomized Controlled Weight-Loss Intervention Trial

Background- Pregnancy may contribute to overweight and obesity. Purpose- The primary objective of Active Mothers Postpartum was to promote a reduction in BMI through 24-months postpartum via sustainable lifestyle changes. Design- Behavioral intervention RCT to enhance postpartum weight loss. Setting/participants- A total of 450 overweight or obese women, enrolled 6-weeks postpartum, were recruited through obstetrics clinics and community posters in the Durham NC area. Intervention- Intervention participants were offered eight healthy-eating classes, ten physical-activity classes, and six telephone-counseling sessions over 9 months. Main outcome measures- Changes from baseline (6-weeks postpartum) to 1-month post-intervention (12-months postpartum) in: (1) diet (caloric intake, calories from fat, intake of certain foods); (2) physical activity (self-reported physical activity, television time); and (3) weight (collected 2004–2007, analyzed 2007–2008). Results- Mean weight loss was 0.90 kg (±5.1 kg) in the intervention group and 0.36 kg (±4.9 kg) in the control group; this difference was not significant. There were also no significant group differences in improvement of diet or increased physical activity. In secondary analyses, there was a positive bivariate relationship between classes attended and weight loss (p=0.01). Conclusions- There were no significant differences among the arms in diet, physical activity, or weight change. Home-based interventions via mail, telephone, or Internet/e-mail may be more feasible and successful in this population. The postpartum period is an important phase in women's lives with regard to weight retention, but engaging them during this busy period remains a challenge. Trial registration- NCT0021225

Effect of Exercise Training on Loss of Bone Mineral Density during Lactation

Purpose: During lactation, women transfer approximately 200 mg of calcium per day to breast milk. For 6 months, this is equivalent to 3%–9% of bone mineral density (BMD) loss at trabecular-rich sites. Bone mass usually returns to prepregnancy levels with cessation of lactation but not in all women. Therefore, the purpose of this study was to determine whether exercise slows bone loss from 4 to 20 wk postpartum (PP).Methods: At 4 wk PP, women were randomized to either an exercise group [EG, n = 10, weight bearing aerobic exercise (3 d·wk-1, 45 min·d-1) and 3 d·wk-1 of resistance exercise] or a control group (CG, n = 10, no exercise) for 16 wk. Body composition and BMD were measured by dual-energy x-ray absorptiometry at the lumbar spine (LS), hip, and total body. Maximal strength and predicted maximal oxygen consumption (V·O2max) were determined by 1-repetition maximum and submaximal treadmill test, respectively. Repeated-measures ANOVA was used to test for time and time by group differences. Results: EG lost significantly less LS BMD than CG (-4.8 ± 0.6% vs -7.0 ± 0.3%, P < 0.01). There were no significant differences in total body and hip BMD. Both groups lost fat mass (EG = -2.9 ± 0.7 kg, CG = -1.8 ± 0.4 kg); however, EG lost less lean body mass (-0.7 ± 0.3 vs -1.6 T 0.3 kg, P = 0.05). Maximal strength increased by 34% to 221% for all exercises in EG, whereas CG changed j5.7% to 12%. Predicted V·O2max increased in both groups (EG = 11.4 ± 2.0, CG = 6.9 ± 1.7%). Conclusions: These results suggest that resistance and aerobic exercise may slow bone loss during lactation

Maternal and infant characteristics associated with human milk feeding in very low birth weight infants.

This study identified maternal and infant characteristics predicting human milk (HM) feeding in very low birth weight (VLBW) infants whose mothers (n = 184) participated in a study of lactation counseling and initiated milk expression. Data were collected prospectively, by maternal interview and medical record review. During hospitalization, 159 (86%) infants received at least 50% HM proportion of feedings in the first 2 weeks of life, and 114 (62%) received some HM until the day of hospital discharge. Analysis showed plan to breastfeed was the strongest predictor of initiation and duration of HM feeding. Greater than 12 years of education, respiratory distress syndrome, Apgar score >6, and female gender were significant predictors, and no perinatal hypertensive disorder, white race, and mechanical ventilation were marginal predictors of HM feeding. Women with a high-risk pregnancy should be provided education about the benefits of breastfeeding for infants who are likely to be born prematurely. J Hum Lact. 25(4):412-419

Effects of Energy Restriction and Exercise on Bone Mineral Density during Lactation

Modest energy restriction combined with resistance training (RT) has been shown in nonlactating women to protect bone during periods of weight loss. However, there is a paucity of research on dietary interventions and exercise in lactating women aimed at promoting bone health and weight loss.Purpose: This study aimed to investigate the effects of energy restriction and exercise on bone mineral density (BMD) and hormones during lactation.Methods: At 4 wk postpartum, participants were randomized to either a 16-wk intervention (diet restricted by 500 kcal and RT 3 d·wk-1) group (IG = 14) or minimal care group (CG = 13). Measurements included BMD by DXA, three 24-h dietary recalls, and hormones. Repeated-measures ANOVA was used to test for group differences over time.Results: Energy intake decreased more in IG (613 ± 521 kcal) than CG (171 ± 435 kcal) (P = 0.03). IG lost more weight (5.8 ± 3.5 kg vs CG = 1.6 ± 5.4 kg, P = 0.02). BMD decreased over time, P < 0.01, with no group differences in lumbar spine (IG = 3.4% ± 2.5%, CG = 3.7% ± 3.3%) or hip (IG and CG = 3.1 ± 1.8%). Prolactin and estradiol decreased over time in both groups, P < 0.01. Basal growth hormone remained stable; however, there was a significant increase in growth hormone response to exercise in IG.Conclusions: These results suggest that moderate energy restriction combined with RT promotes weight loss with no adverse effects on BMD during lactation

The effect of an exercise intervention during early lactation on bone mineral density during the first year postpartum

Background: During lactation, women may lose up to 10% of bone mineral density (BMD) at trabecular-rich sites. Previous studies show that resistance exercise may slow BMD; however, the long-term effects of exercise on BMD during lactation have not been reported. Objective: To evaluate the effect of two 16-week exercise interventions (4- to 20-wk postpartum) in lactating women at 1-year postpartum on lumbar spine, total body, and hip BMD. Methods: To increase sample size at 1-year postpartum, two 16-week exercise interventions were combined for analysis. At 4-week postpartum, 55 women were randomized to intervention group (weight bearing aerobic exercise and resistance exercise) or control group (no exercise) for 16-week, with a 1-year postpartum follow-up. BMD was measured by dual-energy X-ray absorptiometry. Repeated-measures analysis of covariance was used to test for time and group differences for BMD controlling for prolactin concentration and dietary calcium at 1-year postpartum. Results: Change in lumbar spine BMD was significantly different over time and between groups from 4-week to 1-year postpartum, when controlling for prolactin concentration and dietary calcium. There were no significant differences between groups in total body and hip BMD. Conclusion: These results suggest that resistance exercise may slow bone loss during lactation, resulting in higher BMD levels at 1-year postpartum

Effects of a Dairy Supplement and Resistance Training on Lean Mass and Insulin-Like Growth Factor in Women

Purpose: To examine the effect of yogurt supplementation pre- and postexercise on changes in body composition in overweight women engaged in a resistance-training program.Methods: Participants (age = 36.8 ± 4.8 yr) with a body-mass index of 29.1±2.1 kg/m2 were randomized to yogurt supplement (YOG; n = 15) or isoenergetic sucrose beverage (CONT; n = 14) consumed before and after exercise for 16 wk. Participants were also instructed to reduce energy intake daily (–1,046 kJ) during the study. Body composition was assessed by dual-energy X-ray absorptiometry, waist circumference, and sagittal diameter. Strength was measured with 1-repetition maximum. Dietary recalls were obtained by a multipass approach using Nutrition Data System software. Insulin-like growth factor-1 and insulin-like growth-factor-binding protein-3 were measured with ELISA.Results: Significant weight losses of 2.6 ± 4.5 kg (YOG) and 1.2 ± 2.5 kg (CONT) were observed. Total lean weight increased significantly over time in both YOG (0.8 ± 1.2 kg) and CONT (1.1 ± 0.9 kg). Significant reductions in total fat (YOG = 3.4 ± 4.1 kg vs. CONT = 2.3 ± 2.4 kg) were observed over time. Waist circumference, sagittal diameter, and trunk fat decreased significantly over time without group differences. Both groups significantly decreased energy intake while maintaining protein intake. Strength significantly increased over time in both groups. No changes over time or between groups were observed in hormone levels.Conclusions: These data suggest that yogurt supplementation offered no added benefit for increasing lean mass when combined with resistance training and modest energy restriction

Early human milk feeding is associated with a lower risk of necrotizing enterocolitis in very low birth weight infants.

Background: Necrotizing enterocolitis (NEC) is a frequent cause of mortality and morbidity in very low birth weight (VLBW) infants. Human milk (HM) feeding has been associated with lower risk of NEC. However, mothers of VLBW infants often experience insufficient milk production, resulting in mixed feedings of HM and formula. Moreover, medical complications often limit the volume of feeding they can be given. Objective: To determine if high proportions of (50% or greater) HM enteral feeding within the first 14 days of life are protective against NEC. Method: This was a prospective cohort study of VLBW infants who were grouped according to the HM proportion of enteral feeding in the first 14 days: <50% (low human milk, LHM, n=46) and 50% (high human milk, HHM, n=156). The outcome of interest was development of NEC (Bell stage 2 or 3). Logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) and to assess potential confounding due to perinatal risk factors. Result: Two hundred and two infants were studied. Confirmed NEC occurred in 5/46 (10.6%) of the LHM group, as compared with 5/156 (3.2%) of the HHM. Gestational age was the only perinatal factor associated with risk of NEC. After adjustment for gestational age, HHM was associated with a lower risk of NEC ((OR=0.17, 95% CI: 0.04 to 0.68), P=0.01). Conclusion: Enteral feeding containing at least 50% HM in the first 14 days of life was associated with a sixfold decrease in the odds of NEC

Psychosocial predictors of primiparous breastfeeding initiation and duration

Background: Many US women fall short of meeting the recommendations on breastfeeding.Whereas prenatal demographic factors have been well researched in relation to breastfeeding,psychosocial maternal characteristics are less understood but could be important predictors ofbreastfeeding initiation and duration.Objective: This study examined primiparous maternal psychosocial characteristics andtemperamentally based negative infant affect as predictors of breastfeeding initiation andduration while accounting for depression and sociodemographic covariates.Methods: Prenatally, 237 primiparous women were administered the Adult AttachmentInterview and completed a measure of beliefs related to infant crying. At 6 months postpartum,negative infant affect was assessed via mother report. Breastfeeding was assessed at 6 monthsand 1 year postpartum via mother report.Results: Results indicated that younger, low income, less educated, single, ethnic minoritymothers and mothers with elevated depressive symptoms were less likely to initiate breastfeedingand breastfed for a shorter period than other women. Women who initiated breastfeeding tendedto have higher adult attachment coherence scores (more secure attachment) than those who didnot initiate breastfeeding (median score of 6.00 vs 4.00). An interaction was observed betweennegative infant affect and beliefs about crying related to spoiling, such that earlier cessation ofbreastfeeding was observed among mothers who reported high levels of negative infant affectand strongly endorsed the belief that responding to cries spoils infants (hazard ratio = 1.71, P Conclusion: Although these psychosocial variables predicted relatively little variation inbreastfeeding over and above covariates, the results suggest some novel approaches to promotebreastfeeding