Mothers' Use of Social Media to Inform Their Practices for Pumping and Providing Pumped Human Milk to Their Infants

Despite U.S. mothers’ wide adoption of pumps and bottles to provide human milk (HM) to their infants, mothers lack comprehensive, evidence-based guidelines for these practices. Thus, some women use online sources to seek information from each other. We aimed to characterize the information women sought online about pumping. We used data provided by ~25,000 women in an open cohort within a discussion forum about parenting. We examined 543 posts containing questions about providing pumped HM cross-sectionally and longitudinally in three time intervals: prenatal, 0 through 1.5 months postpartum, and 1.5 to 4.5 months postpartum. We used thematic analysis with Atlas.ti to analyze the content of posts. During pregnancy, women commonly asked questions about how and where to obtain pumps, both out-of-pocket and through insurance policies. Between 0–1.5 months postpartum, many mothers asked about how to handle pumped HM to ensure its safety as fed. Between 1.5–4.5 months postpartum, mothers sought strategies to overcome constraints to pumping both at home and at work and also asked about stopping pumping and providing their milk. Women’s questions related to ensuring the safety of pumped HM represent information women need from health professionals, while their questions related to obtaining pumps suggest that women may benefit from clearer guidelines from their insurance providers. The difficulties women face at home and at work identify avenues through which families and employers can support women to meet their goals for providing HM.

Environmental organic pollutants in human milk before and after weight loss

Many persistent organic pollutants (POPs) are banned because they accumulate in organisms and are toxic. Lipophilic POPs are stored in maternal adipose tissue and concentrations in human milk (HM) may increase during weight loss. Our aim was to examine associations between weight loss and concentrations of chlorinated POPs in HM in lactating women participating in a weight loss study. We analysed POPs (PCB 28, PCB 153, HCB, DDE) in HM at 12 and 24 weeks postpartum from 32 women who participated in a randomized, 2 × 2 factorial trial of diet and exercise for postpartum weight loss. Participants donated milk before and after the intervention period. We examined associations between weight loss and change in POP concentrations and estimated the intake of POPs by their breastfed infants. Most (n = 27) women lost weight during intervention, 0.45 ± 0.30 kg/week (mean ± SD). Among these women, the concentration of PCB 153 in HM was significantly (p = 0.04) higher at follow-up than at baseline. Weight loss was significantly positively associated with changes in concentrations of all studied POPs (2.0-2.4% increase per percent weight loss). Estimated mean intakes of POPs (ng/day) remained stable because infant milk consumption decreased during the study period. As infants gained weight, estimated mean intakes per kg body weight decreased 17-22%. Changes in concentrations of POPs in HM correlated positively with maternal weight loss, but it is unlikely that the balance between the benefits and risks of breastfeeding will change if the weight loss is restricted to 0.5 kg per week.

Informal Human Milk Sharing: A Qualitative Exploration of the Attitudes and Experiences of Mothers

BACKGROUND

Little is known about women's participation or likely participation in informal human milk (HM) sharing. The US Food and Drug Administration recommends against feeding infants shared HM acquired directly from individuals or through the Internet.

OBJECTIVE

This study explored the experiences of and attitudes toward HM sharing among mothers with experience of HM feeding and breast pump use, regardless of whether or not they had participated in HM sharing.

METHODS

We conducted qualitative, semistructured, in-depth interviews with 41 mothers from 4 counties in upstate New York, asking about their attitudes toward HM sharing. Interviews were transcribed and analyzed inductively.

RESULTS

Most women were aware of informal HM sharing and some had personal experience with sharing. Many mothers reported a willingness to provide their own HM if they had extra and their own child had enough. Mothers were less trusting about receiving HM, voicing concerns about the dietary intake or disease status of potential providers. Mothers felt that whether or not they participated in HM sharing would depend on the situation; they were most amenable to sharing with a family member or close friend. A novel finding was the involvement of lactation consultants and midwives, who coordinated HM exchanges for mothers in this sample.

CONCLUSION

Awareness of HM sharing was high in this sample. Depending on the situation, mothers may consider participating in informal HM sharing and they may be facilitated by health professionals. Future research is required to establish the benefits and risks associated with informal HM sharing.

Obese women experience multiple challenges with breastfeeding that are either unique or exacerbated by their obesity: discoveries from a longitudinal, qualitative study

Obese women are at risk for shorter breastfeeding duration, but little is known about how obese women experience breastfeeding. The aim of this study was to understand obese women's breastfeeding experiences. We enrolled pregnant women in upstate New York, who were either obese [n = 13; body mass index (BMI) ≥30 kg/m² ] or normal weight (n = 9; BMI 18.5-24.9 kg/m² ) before conception and intended to breastfeed. A longitudinal, qualitative study was conducted from February 2013 through August 2014 with semi-structured interviews during pregnancy and at specific times post-partum through 3 months. Interviews were audio recorded, transcribed and analyzed using content analysis. Themes that emerged in analysis were compared between obese and normal-weight women. Differences were identified and described. Prenatally, obese women expressed less confidence about breastfeeding than normal-weight women. Post-partum, obese women and their infants had more health issues that affected breastfeeding, such as low infant blood glucose. Compared with normal-weight women, they also experienced more challenges with latching and positioning their infants. Breastfeeding required more time, props and pillows, which limited where obese women could breastfeed. Obese women also experienced more difficulty finding nursing bras and required more tangible social support than normal-weight women. In conclusion, obese women experienced more challenges than women of normal weight; some challenges were similar to those of normal-weight women but were experienced to a greater degree or a longer duration. Other challenges were unique. Obese women could benefit from targeted care prenatally and during the hospital stay as well as continued support post-partum to improve breastfeeding outcomes. © 2016 John Wiley & Sons Ltd.

Pumping human milk in the early postpartum period: its impact on long-term practices for feeding at the breast and exclusively feeding human milk in a longitudinal survey cohort

BACKGROUND

Most American mothers who feed human milk (HM) now use pumps to produce some of the HM they feed. Pumping is nationally recommended, but associations between pumping and HM-feeding durations are unknown.

OBJECTIVES

We examined whether and how the pumping frequency and types of reasons for pumping between 1.5 and 4.5 mo postpartum are associated with HM-feeding durations. We classified pumping reasons as nonelective [e.g., because of a difficulty feeding at the breast (FAB)] or elective (e.g., to produce HM to mix with solids). We hypothesized that women who pumped more frequently or nonelectively would have shorter HM-feeding durations.

DESIGN

We used data from 1116 mothers in a longitudinal cohort who fed and pumped HM 1.5-4.5 mo postpartum. We used χ(2) and Cox proportional hazards regression models to examine the survival of any HM feeding, exclusive HM feeding, and FAB.

RESULTS

Compared with mothers who pumped for elective reasons, mothers who reported one nonelective reason had greater hazards of stopping feeding any HM (HR: 1.12; 95% CI: 1.05, 1.21) or exclusive HM (HR: 1.14; 95% CI: 1.09, 1.20) and of stopping FAB (HR: 2.07; 95% CI: 1.77, 2.42). Mothers who pumped most frequently had the highest mean hazards of stopping feeding any HM (HR: 1.82; 95% CI: 1.68, 1.93) and feeding exclusive HM (HR: 1.21; 95% CI: 1.14, 1.26). Hazards of stopping FAB varied across the year. Compared with the least-frequent pumpers, the most-frequent pumpers had a 2.6-fold higher hazard of stopping FAB at 3 mo postpartum and a 1.7-fold higher hazard at 6 mo postpartum.

CONCLUSIONS

Nonelective pumping reasons and higher pumping frequency were associated with shorter HM-feeding durations. Mothers who report that they use a breast pump for reasons related to either employment or FAB difficulty and their infants may be more vulnerable to risks associated with a shorter HM-feeding duration.

Discontinuity of Breastfeeding Care: "There's No Captain of the Ship"

BACKGROUND

Breastfeeding rates in the United States are suboptimal. Health professionals (HPs) have a unique opportunity to support breastfeeding because of the frequency and timing of their visits with mothers and infants as well as their call by professional organizations to do so. The objective of this study was to understand HPs' perceived roles and experiences with providing breastfeeding-related care.

MATERIALS AND METHODS

In-depth qualitative interviews were conducted with 34 HPs (obstetricians, midwives, pediatricians, nurses, and lactation consultants) who care for pregnant or lactating women. Interviews were audio-recorded, transcribed, and verified for accuracy; content analysis was used to identify themes using a grounded theory approach.

RESULTS

The overarching theme was discontinuity in breastfeeding care across the continuum. Most HPs relied on other HPs to provide breastfeeding care, which resulted from and contributed to problematic gaps in care that were reported. A minority of HPs attempted to bridge gaps in breastfeeding care or improve continuity. Contributing to the discontinuity were a lack of time, lack of skills, inconsistent messages, and low communication across stages of care. HPs were unsure whether their help was effective and whether required follow-up was completed.

CONCLUSIONS

Despite HPs' recognition of breastfeeding as the best choice for infant feeding, breastfeeding care may be disjointed and a barrier to achieving breastfeeding recommendations. These problems should be investigated and systemically addressed in future research so that maternal-infant dyad breastfeeding care can be improved.

Early Breastfeeding Problems Mediate the Negative Association between Maternal Obesity and Exclusive Breastfeeding at 1 and 2 Months Postpartum

BACKGROUND

Compared with normal-weight women, women with obesity experience poorer breastfeeding outcomes. Successful breastfeeding among women with obesity is important for achieving national breastfeeding goals.

OBJECTIVES

The objectives were to determine whether the negative association between obesity and any or exclusive breastfeeding at 1 and 2 mo postpartum is mediated through breastfeeding problems that occur in the first 2 wk postpartum and if this association differs by parity.

METHODS

Mothers (1151 normal-weight and 580 obese) in the Infant Feeding Practices Study II provided information on sociodemographic and psychosocial characteristics, body mass index, and breastfeeding outcomes. At 1 mo postpartum, participants reported the breastfeeding problems they experienced in the first 2 wk postpartum from a predefined list of 17 options. We used factor analysis to condense these problems into 4 explanatory variables; continuous factor scores were computed for use in further analyses. We used maximum likelihood logistic regression to assess mediation of the association between obesity and breastfeeding outcomes through early breastfeeding problems.

RESULTS

No significant effect of obesity was found on any breastfeeding at 1 or 2 mo. At 1 mo postpartum, for both primiparous and multiparous women, there was a significant direct effect of obesity on exclusive breastfeeding and a significant indirect effect of obesity through early breastfeeding problems related to the explanatory mediating variable "Insufficient Milk" (throughout the remainder of the Abstract, this factor will be denoted by upper case notation). At 2 mo postpartum both the direct effect of obesity and the indirect effect through Insufficient Milk were significant in primiparous women but only the indirect effect remained significant in multiparous women.

CONCLUSIONS

Early problems related to Insufficient Milk may partially explain the association between obesity and poor exclusive breastfeeding outcomes. Women who are obese, particularly those reporting breastfeeding problems that grouped in the Insufficient Milk factor in the early postpartum period, may benefit from additional breastfeeding support.

Maternal prepregnancy waist circumference and BMI in relation to gestational weight gain and breastfeeding behavior: the CARDIA study

BACKGROUND

Studies suggest that gestational weight gain (GWG) and breastfeeding behavior may influence long-term maternal abdominal fat mass. However, this could be confounded by abdominal fat mass before pregnancy because it is unknown whether abdominal fat mass, independently of body size, affects GWG and breastfeeding behavior.

OBJECTIVE

We investigated how maternal prepregnancy fat distribution, described by waist circumference (WC) and body mass index (BMI), is associated with GWG and breastfeeding behavior.

DESIGN

We analyzed 1371 live births to 1024 women after enrollment in the Coronary Artery Risk Development in Young Adults study (1985-1996). For each birth, maternal prepregnancy BMI and WC were measured at year 0 (baseline), 2, 5, or 7 examinations. Recalled GWG and breastfeeding behavior were collected at years 7 and 10. GWG was analyzed by using linear regression and breastfeeding behavior by using logistic regression and discrete-time logistic regression.

RESULTS

Adjusted for potential confounders, a 1-cm larger WC adjusted for BMI was associated with a 0.19-kg (95% CI: -0.29-, -0.10-kg) lower GWG. In contrast, a 1-unit higher BMI adjusted for WC was associated with a 0.27-kg (95% CI: 0.06-, 0.47-kg) higher GWG. The OR for ever breastfeeding compared with never breastfeeding was 0.93 (95% CI: 0.90, 0.97) per 1-cm larger WC after adjustment for BMI, whereas it was 1.10 (95% CI: 1.02, 1.19) per 1-unit higher BMI adjusted for WC.

CONCLUSIONS

Maternal prepregnancy body size was differently associated with GWG and breastfeeding behavior depending on the location of the fat mass. Thus, maternal fat distribution may be a more important determinant of GWG and breastfeeding behavior than BMI alone.

Maternal weight change from prepregnancy to 7 years postpartum--the influence of behavioral factors

OBJECTIVE

We studied the influence of maternal behavior on weight change from prepregnancy to 7 years postpartum.

METHODS

We used linear regression to study the independent and combined associations between self-reported behavior in pregnancy (dietary intake, leisure-time exercise, sedentary activity, smoking) and postpartum (breastfeeding duration and smoking) on weights at 6 months, 18 months, and 7 years postpartum.

RESULTS

Women's average 7-year weight gain was 2.07 kg, with 23% gaining >5 kg. Multivariable analyses suggested that women with healthier dietary intake, more leisure-time exercise, less sedentary behavior, and longer duration of breastfeeding on average gained 1.66 kg [95% confidence interval (CI): 1.40; 1.91] with a significantly reduced odds [OR 0.56 (95% CI: 0.49; 0.64)] of gaining >5 kg from prepregnancy to 7 years postpartum compared to women with none or one of these behaviors [mean gain 3.03 kg (95% CI: 2.68; 3.39)]. Women who ceased smoking had higher long-term weight gain than nonsmokers, but not smokers.

CONCLUSIONS

Adherence to healthy behaviors during pregnancy lowered long-term weight gain considerably by lowering postpartum weight retention and subsequent weight gain. Public health efforts to help mothers achieve healthy behaviors might prevent childbearing-related weight gain.

Health professionals' experiences providing breastfeeding-related care for obese women

BACKGROUND

Obese women are at high risk of early breastfeeding cessation, and health professionals (HPs) have a unique opportunity to provide them with breastfeeding support. Our objective was to describe HPs' experiences providing breastfeeding care for obese women during the prenatal, peripartum, and postpartum periods.

MATERIALS AND METHODS

In-depth, qualitative interviews were conducted with 34 HPs (including obstetricians, midwives, pediatricians, nurses, and lactation consultants) who care for pregnant or lactating women. They were recruited from a variety of settings in central New York. Interviews were audio-recorded, transcribed, verified for accuracy, and then analyzed qualitatively.

RESULTS

HPs identified obesity in multiple ways, some of which were consistent with standard cutoffs, whereas others implied extreme obesity. Nearly all HPs discussed ways they perceive obese women have challenges with breastfeeding. Some HPs described challenges as specific to obese women (e.g., limited mobility), whereas others described challenges as universal but more likely to occur among obese women (e.g., difficulties positioning the infant to breastfeed). Across professions, HPs described providing breastfeeding care for obese women as requiring more time and physical work and as being more challenging. HPs acknowledged stigma around obesity and discussed treating obese women with dignity and the same as other women. Strategies were suggested for improving breastfeeding support for obese women.

CONCLUSIONS

HPs identified multiple challenges that obese women encounter with breastfeeding, as well as their own challenges with providing care. Comprehensive strategies are needed to assist obese women with breastfeeding and to alleviate strain on HPs who provide their care.

Effects of body size and change in body size from infancy through childhood on body mass index in adulthood

BACKGROUND

Weight and weight gain throughout infancy are related to later obesity, but whether the strength of the associations varies during the infancy period is uncertain.

AIMS

Our aims were to identify the period of infancy when change in body weight has the strongest association with adult body mass index (BMI) and also the extent to which these associations during infancy are mediated through childhood BMI.

METHODS

The Copenhagen Perinatal Cohort, in which participants were followed from birth through 42 years of age, provided information on weight at 12 months and BMI at 42 years for 1633 individuals. Information on weight at birth, 2 weeks, 1, 2, 3, 4 and 6 months was retrieved from health visitors' records and information on BMI at ages 7 and 13 years from school health records. The associations of infant weight and weight gain standard deviation scores (SDS) with adult BMI-SDS were analyzed using multiple linear regression and path analysis.

RESULTS

Higher-weight-SDS at all ages from birth to an age 12 months were associated with higher-BMI-SDS at 42 years (regression coefficients 0.08-0.12). Infant weight gain-SDS was associated with greater BMI-SDS at 42 years only between birth and 3 months (0.09, 95% confidence intervals (CI) 0.04, 0.15) driven by an association between 2 and 3 months (0.12, 95% CI: 0.04, 0.20). The latter was partly mediated through later BMI in the path analysis. Infant weight gain-SDS between 3 and 12 months was not associated with greater BMI-SDS at 42 years.

CONCLUSIONS

Faster weight gain during only the first 3 months of infancy was associated with increased adult BMI, although not in a consistent monthly pattern. Adult BMI is more sensitive to high weight gain during early infancy than late infancy, but not specifically to the first month of life.

Prediction of excessive gestational weight gain from week-specific cutoff values: a cohort study

OBJECTIVE

To assess the prognostic validity of the Institute of Medicine/National Research Council (IOM/NRC) week-specific cutoff values for inadequate or excessive total gestational weight gain (GWG) by 4-week intervals.

STUDY DESIGN

We merged data from two German cohorts (LMU cohort (all maternal-weight categories) and PEACHES cohort (obese women)) to provide information on GWG for 749 women (365 normal weight, 199 overweight and 185 obese). We calculated the prognostic values for suboptimal and excessive GWG according to the IOM/NRC cutoff values.

RESULT

The positive predictive values for excessive total GWG for those who experienced excessive GWG early in pregnancy was 70.1% (95% confidence interval (CI) 60.5; 78.6) as of week 12/1 to 16/0 in normal-weight women, 89.5% (95% CI 75.2; 97.1) and 95.2 (76.2; 99.9) 95.2% (95% CI 76.2; 99.9) as of week 8/1 to 12/0 for overweight and obese women, respectively. In absence of excessive GWG as of week 12/1 to 16/0, normal-weight women had 77.5% (95% CI 77.1; 83.1) probability of not experiencing excessive total GWG (negative predictive value). In overweight and obese women, the negative predictive value was considerably lower up to week 24/1 to 28/0 (60.0% (95% CI 48.8; 70.5) in week 20/1 to 24/0 and 50.6% (95% CI 39.3; 61.9) in week 24/1 to 28/0). Most women with inadequate GWG in the first and second trimester had adequate total final GWG (positive predictive value for total inadequate GWG <50% up to week 16/1 to 20/0 in all groups).

CONCLUSION

As women with excessive weight gain can be identified with high confidence if the GWG exceeds the IOM/NRC week-specific cutoff values, interventions may be initiated early in pregnancy.

Associations of maternal obesity and psychosocial factors with breastfeeding intention, initiation, and duration

BACKGROUND

Psychosocial factors influence breastfeeding outcomes, but little is known about these characteristics and how they influence breastfeeding behavior of obese women, who are a group that experiences poor breastfeeding outcomes.

OBJECTIVES

Our objectives were to determine whether 1) maternal prepregnancy body mass index (BMI) is associated with social knowledge of, social influence toward, maternal confidence in, and behavioral beliefs about breastfeeding; 2) BMI and these psychosocial factors predict outcomes of intention to breastfeed, ever breastfed, and the duration of breastfeeding; and 3) BMI and psychosocial factors are associated with these breastfeeding outcomes independent of each other.

DESIGN

Participants (n = 2824) in the Infant Feeding Practices Study II provided data on psychosocial characteristics and breastfeeding outcomes. In this prospective cohort study, data were analyzed by using logistic and proportional hazards regression models.

RESULTS

Prepregnancy BMI was associated with confidence in (P < 0.0001), social influence toward (P = 0.02), and social knowledge of (P < 0.0001) breastfeeding but not with behavioral beliefs about breastfeeding (P = 0.45). Obese women did not differ from under- and normal-weight women in the intention to breastfeed (P = 0.07) but had lower odds of ever breastfeeding (P = 0.04) and were at greater risk of an earlier cessation of exclusive (P = 0.0009) and any (P = 0.03) breastfeeding. Only the association with exclusive breastfeeding remained significant after controlling for psychosocial factors (P = 0.01). All psychosocial factors were positively associated with each breastfeeding outcome.

CONCLUSIONS

Despite their intentions to breastfeed, women with high prepregnancy BMI had psychosocial characteristics associated with poor breastfeeding outcomes. However, these characteristics did not fully explain the association between maternal obesity and breastfeeding outcomes.

Diet and exercise interventions among overweight and obese lactating women: randomized trial of effects on cardiovascular risk factors

Objective

To examine the effects of Diet (D) and Exercise (E) interventions on cardiovascular fitness, waist circumference, blood lipids, glucose metabolism, inflammation markers, insulin-like growth factor 1 (IGF-1) and blood pressure in overweight and obese lactating women.

Methods

At 10–14 wk postpartum, 68 Swedish women with a self-reported pre-pregnancy BMI of 25–35 kg/m² were randomized to a 12-wk behavior modification treatment with D, E, both or control using a 2×2 factorial design. The goal of D treatment was to reduce body weight by 0.5 kg/wk, accomplished by decreasing energy intake by 500 kcal/d and monitoring weight loss through self-weighing. The goal of E treatment was to perform 4 45-min walks per wk at 60–70% of max heart-rate using a heart-rate monitor. Effects were measured 12 wk and 1 y after randomization. General Linear Modeling was used to study main and interaction effects adjusted for baseline values of dependent variable.

Results

There was a significant main effect of the D treatment, decreasing waist circumference (P = 0.001), total cholesterol (P = 0.007), LDL-cholesterol (P = 0.003) and fasting insulin (P = 0.042), at the end of the 12-wk treatment. The decreased waist circumference (P<0.001) and insulin (P = 0.024) was sustained and HDL-cholesterol increased (P = 0.005) at the 1-y follow-up. No effects from the E treatment or any interaction effects were observed.

Conclusions

Dietary behavior modification that produced sustained weight loss among overweight and obese lactating women also improved risk factors for cardiovascular disease and type 2 diabetes. This intervention may not only reduce weight-related risks with future pregnancies but also long-term risk for metabolic disease.

Trial registration

ClinicalTrials.gov NCT01343238

How do pregnancy-related weight changes and breastfeeding relate to maternal weight and BMI-adjusted waist circumference 7 y after delivery? Results from a path analysis

BACKGROUND

Reproduction has been related to long-term maternal weight gain, and changes in fat mass, with gestational weight gain, have been identified as an important contributor. However, the influence of weight changes during the whole reproductive cycle and the modifying effect of breastfeeding are unknown.

OBJECTIVE

The objective was to examine how prepregnancy weight, gestational weight gain, postpartum weight changes, and breastfeeding influence maternal weight and body mass index-adjusted waist circumference (WCBMI) 7 y after delivery.

DESIGN

This was a prospective cohort study of 23,701 women participating in the Danish National Birth Cohort with singleton births and no births during follow-up. Path analysis was used to assess the total, direct, and indirect effects; the latter was mediated through weight changes on the pathways.

RESULTS

Postpartum weight retention at 6 mo and weight gain from 6 to 18 mo postpartum were highly positively associated with both outcomes. A 1-kg increase in weight retention at 6 mo postpartum corresponded to an average increase of 0.5 kg at 7 y. Gestational weight gain was not associated with WCBMI but was positively associated with weight at 7 y; 87% of this effect was mediated through later weight changes. For both outcomes, a small inverse association was observed for breastfeeding duration. This was strongest for WCBMI, for which 97% of the effect was direct, ie, not mediated through postpartum weight.

CONCLUSIONS

These findings show that postpartum weight retention at 6 mo and weight gain from 6 to 18 mo postpartum contribute equally to adverse maternal anthropometric measures 7 y after delivery. Breastfeeding duration may have a beneficial effect.

Environmental exposure to metals and children's growth to age 5 years: a prospective cohort study

In this prospective cohort study, based on 1,505 mother-infant pairs in rural Bangladesh, we evaluated the associations between early-life exposure to arsenic, cadmium, and lead, assessed via concentrations in maternal and child urine, and children's weights and heights up to age 5 years, during the period 2001–2009. Concurrent and prenatal exposures were evaluated using linear regression analysis, while longitudinal exposure was assessed using mixed-effects linear regression. An inverse association was found between children's weight and height, age-adjusted z scores, and growth velocity at age 5 years and concurrent exposure to cadmium and arsenic. In the longitudinal analysis, multivariable-adjusted attributable differences in children's weight at age 5 years were −0.33 kg (95% confidence interval (CI): −0.60, −0.06) for high (≥95th percentile) arsenic exposure and −0.57 kg (95% CI: −0.88, −0.26) for high cadmium exposure, in comparison with children with the lowest exposure (≤5th percentile). Multivariable-adjusted attributable differences in height were −0.50 cm (95% CI: −1.20, 0.21) for high arsenic exposure and −1.6 cm (95% CI: −2.4, −0.77) for high cadmium exposure. The associations were apparent primarily among girls. The negative effects on children's growth at age 5 years attributable to arsenic and cadmium were of similar magnitude to the difference between girls and boys in terms of weight (−0.67 kg, 95% CI: −0.82, −0.53) and height (−1.3 cm, 95% CI: −1.7, −0.89).

Late pregnancy reversal from excessive gestational weight gain lowers risk of childhood overweight--a cohort study

OBJECTIVE

Whether reversal to adequate gestational weight gain (GWG) in the third trimester reverses the risk for childhood overweight associated with excessive GWG is assessed.

DESIGN AND METHODS

In a retrospective cohort study in 6,665 mother-child pairs, pre-pregnancy weight and the temporal course of GWG were collected from medical records. Overweight as defined by International Obesity Task Force was assessed at a mean age of 5.8 years. Main exposures were exceeding week-specific cut-off values for GWG in the third trimester or any previous trimester. Logistic regression models, adjusted for possible confounding factors, were used to predict the risk of childhood overweight from excessive GWG in the third trimester with stratification by excessive GWG in previous trimesters.

RESULTS

In the final model, women who avoided excessive GWG in the third trimester had children with a 31% (odds ratio [OR]: 0.69, 95% confidence interval [CI]: 0.59, 0.82) lower probability being overweight. A similar association was observed for reversing from excessive GWG in the first or second trimester to normal GWG in the third trimester: 27% (OR: 0.73, 95% CI: 0.53, 0.99).

CONCLUSIONS

Avoidance of excessive GWG in the third trimester is associated with lower risk of childhood overweight even in case of excessive GWG in the first or second trimester.

Comparison of gestational weight gain-related pregnancy outcomes in American primiparous and multiparous women

BACKGROUND

In Danish data, the tradeoffs between mother and infant in the risks of adverse pregnancy outcomes were reached at lower gestational weight gain (GWG) among multiparous than among primiparous women. It is unknown whether the same difference exists among American women.

OBJECTIVE

The objective was to determine whether these tradeoffs also differ by parity among women in a contemporary American birth cohort.

DESIGN

Data from 822 primiparous and 2055 multiparous American women who participated in the Infant Feeding Practices Study II (2005-2007), a national cohort study, were analyzed. Their self-reported GWG was divided into 4 categories (≤10, >10 to <15, 15 to <20, and ≥20 kg). GWG-specific absolute adjusted risks for emergency cesarean delivery, birth of a small-for-gestational-age (SGA) or large-for-gestational-age (LGA) infant, and postpartum weight retention at 6 mo were estimated by multiple logistic regression analyses for women in 3 categories of prepregnancy body mass index.

RESULTS

Primiparous women gained more weight during pregnancy than did multiparous women (mean ± SD: 15.9 ± 6.9 compared with 13.5 ± 6.2 kg; P < 0.0001). The absolute adjusted risk of postpartum weight retention rose steeply with increasing GWG among both primiparous and multiparous women. The risk of emergency cesarean delivery and of delivering LGA infants increased with increasing GWG only among multiparous women. The risk of SGA tended to decrease with increasing GWG in both parity groups.

CONCLUSION

These findings extend the concept of a lower optimal GWG among multiparous than primiparous women to American women.