How should gestational weight gain be assessed? A comparison of existing methods and a novel method, area under the weight gain curve

Associations of Neighborhood Opportunity and Social Vulnerability With Trajectories of Childhood Body Mass Index and Obesity Among US Children

Importance

Physical and social neighborhood attributes may have implications for children's growth and development patterns. The extent to which these attributes are associated with body mass index (BMI) trajectories and obesity risk from childhood to adolescence remains understudied.

Objective

To examine associations of neighborhood-level measures of opportunity and social vulnerability with trajectories of BMI and obesity risk from birth to adolescence.

Design, Setting, and Participants

This cohort study used data from 54 cohorts (20 677 children) participating in the Environmental Influences on Child Health Outcomes (ECHO) program from January 1, 1995, to January 1, 2022. Participant inclusion required at least 1 geocoded residential address and anthropometric measure (taken at the same time or after the address date) from birth through adolescence. Data were analyzed from February 1 to June 30, 2022.

Exposures

Census tract-level Child Opportunity Index (COI) and Social Vulnerability Index (SVI) linked to geocoded residential addresses at birth and in infancy (age range, 0.5-1.5 years), early childhood (age range, 2.0-4.8 years), and mid-childhood (age range, 5.0-9.8 years).

Main Outcomes and Measures

BMI (calculated as weight in kilograms divided by length [if aged <2 years] or height in meters squared) and obesity (age- and sex-specific BMI ≥95th percentile). Based on nationwide distributions of the COI and SVI, Census tract rankings were grouped into 5 categories: very low (<20th percentile), low (20th percentile to <40th percentile), moderate (40th percentile to <60th percentile), high (60th percentile to <80th percentile), or very high (≥80th percentile) opportunity (COI) or vulnerability (SVI).

Results

Among 20 677 children, 10 747 (52.0%) were male; 12 463 of 20 105 (62.0%) were White, and 16 036 of 20 333 (78.9%) were non-Hispanic. (Some data for race and ethnicity were missing.) Overall, 29.9% of children in the ECHO program resided in areas with the most advantageous characteristics. For example, at birth, 26.7% of children lived in areas with very high COI, and 25.3% lived in areas with very low SVI; in mid-childhood, 30.6% lived in areas with very high COI and 28.4% lived in areas with very low SVI. Linear mixed-effects models revealed that at every life stage, children who resided in areas with higher COI (vs very low COI) had lower mean BMI trajectories and lower risk of obesity from childhood to adolescence, independent of family sociodemographic and prenatal characteristics. For example, among children with obesity at age 10 years, the risk ratio was 0.21 (95% CI, 0.12-0.34) for very high COI at birth, 0.31 (95% CI, 0.20-0.51) for high COI at birth, 0.46 (95% CI, 0.28-0.74) for moderate COI at birth, and 0.53 (95% CI, 0.32-0.86) for low COI at birth. Similar patterns of findings were observed for children who resided in areas with lower SVI (vs very high SVI). For example, among children with obesity at age 10 years, the risk ratio was 0.17 (95% CI, 0.10-0.30) for very low SVI at birth, 0.20 (95% CI, 0.11-0.35) for low SVI at birth, 0.42 (95% CI, 0.24-0.75) for moderate SVI at birth, and 0.43 (95% CI, 0.24-0.76) for high SVI at birth. For both indices, effect estimates for mean BMI difference and obesity risk were larger at an older age of outcome measurement. In addition, exposure to COI or SVI at birth was associated with the most substantial difference in subsequent mean BMI and risk of obesity compared with exposure at later life stages.

Conclusions and Relevance

In this cohort study, residing in higher-opportunity and lower-vulnerability neighborhoods in early life, especially at birth, was associated with a lower mean BMI trajectory and a lower risk of obesity from childhood to adolescence. Future research should clarify whether initiatives or policies that alter specific components of neighborhood environment would be beneficial in preventing excess weight in children.

Maternal Obesity as a Risk Factor for Caesarean Delivery in Sub-Saharan Africa: A Systematic Review

Background: Maternal obesity is associated with several adverse reproductive outcomes. It is a growing public health burden in sub-Saharan Africa, a region with low resources and capacity to care for the large, affected population. Objectives: To assess the evidence of maternal obesity as a risk factor for caesarean delivery in women in sub-Saharan Africa. Methods: A systematic review of relevant original articles using PubMed, MEDLINE, and CINAHL was performed. Google Scholar and the reference lists of relevant systematic reviews and meta-analyses were also searched for other eligible studies. Observational studies assessing maternal body mass index (BMI) ≥ 30 kg/m2 before or during gestation and caesarean delivery as birth outcome were included. Results: All 17 studies were published between 2009 and 2021 and included 227,675 (236−153,102) participants. The prevalence of maternal obesity ranged from 3.9 to 44%. All except two studies (88%) indicated an association of obesity and risk of caesarean delivery in pregnant women in sub-Saharan Africa. Overweight/obese women had up to 4-fold increased risk of caesarean delivery compared to normal weight women. Three studies also reported a direct relationship between morbid obesity and prevalence of caesarean delivery in the sub-region. The risk of caesarean delivery appears to increase with increasing BMI e.g., >5 times in women with BMI ≥ 40 kg/m2 than in normal weight women. Conclusions: In sub-Saharan Africa, increased BMI in pregnancy is a risk factor for subsequent caesarean delivery. The risk of caesarean delivery appears to increase with increasing BMI. A robust meta-analysis and other patho-mechanistic studies can be conducted to confirm causal association. Culturally appropriate weight management and nutritional interventions should be implemented to reduce the incidence of obesity-induced caesarean delivery in sub-Saharan Africa.

Associations of midchildhood to early adolescence central adiposity gain with cardiometabolic health in early adolescence

OBJECTIVE

This study examined the associations of central adiposity gain from midchildhood to early adolescence with cardiometabolic health markers in early adolescence.

METHODS

A total of 620 participants were studied in Project Viva. In midchildhood (mean age = 7.8 years) and early adolescence (12.9 years), waist circumference and dual-energy x-ray absorptiometry-measured visceral adipose tissue, subcutaneous abdominal adipose tissue, and trunk fat were obtained. Central adiposity gain was calculated as change per year between visits. Cardiometabolic health markers, including blood pressure, lipids, markers of insulin resistance, inflammation, and adipokines, were collected in early adolescence.

RESULTS

Greater waist circumference gain was associated with higher log triglycerides (β 0.07 mg/dL; 95% CI: 0.02-0.13), log alanine aminotransferase (0.07 U/L; 95% CI: 0.03-0.12), log high-sensitivity C-reactive protein (0.43 mg/L; 95% CI: 0.28-0.58), and other cardiometabolic markers in early adolescence. Directly measured central adiposity gains were associated with higher systolic blood pressure z score in early adolescence (visceral adipose tissue [0.13 SD units; 95% CI: 0.04-0.23], subcutaneous abdominal adipose tissue [0.18 SD units; 95% CI: 0.04-0.31], and trunk fat [0.21 SD units; 95% CI: 0.06-0.36]). These associations were independent of baseline and change in total adiposity from midchildhood to early adolescence.

CONCLUSIONS

Monitoring central adiposity gain may enable identification and intervention in children vulnerable to developing cardiometabolic health risks.

Gestational weight gain in sub-Saharan Africa: Estimation based on pseudo-cohort design

Background

Inadequate or excess gestational weight gain (GWG) leads to multiple undesirable birth outcomes. Yet, in sub-Saharan Africa (SSA) little is known about the weight gain pattern in pregnancy. The purpose of the study is to estimate the average gestational weight gain (GWG) in sub-Saharan Africa (SSA) and to examined whether there had been recent improvements or not.

Methods

Based on cross-sectional anthropometric data extracted from multiple Demographic and Health Surveys conducted in SSA, we estimated the average GWG in the region. Pseudo-cohort design was used to reconstruct GWG trajectories based on aggregated data of 110,482 women extracted from 30 recent surveys. Trend in GWG between 2000 and 2015 was determined using the data of 11 SSA countries. Pre-pregnancy weight was estimated based on the weight of non-pregnant women at risk of conception.

Results

On average, women in SSA gain inadequate weight (6.6 kg, 95% confidence interval, 6.0–7.2) over pregnancy. No meaningful gain was observed in the first trimester; whereas, women in the second and third trimesters put on 2.2 and 3.2 kg, respectively. The highest weight gain (10.5, 8.2–12.9 kg) was observed in Southern African sub-region and the lowest in Western Africa (5.8, 5.0–6.6 kg). The GWG among women who had secondary or above education (9.5, 8.2–10.9 kg) was higher than women with lower education (5.0, 4.3–5.8 kg). Likewise, GWG in women from richest households (9.0, 7.2–10.7 kg) was superior to those from poorest households (6.1, 5.3–7.0 kg). The estimated recent (2015–20) mean GWG (6.6, 5.8–7.4 kg) was not significantly different from what had been at beginning of the new millennium (6.7, 5.9–7.5 kg).

Conclusion

In SSA GWG is extremely low and is not showing improvements.

Effect of Correcting the Postnatal Age of Preterm-Born Children on Measures of Associations Between Infant Length-for-Age z Scores and Mid-Childhood Outcomes

Child growth standards are commonly used to derive age- and sex-standardized anthropometric indices but are often inappropriately applied to preterm-born children (<37 weeks of gestational age (GA)) in epidemiology studies. Using the 2004 Pelotas Birth Cohort, we examined the impact of correcting for GA in the application of child growth standards on the magnitude and direction of associations in 2 a priori–selected exposure-outcome scenarios: infant length-for-age z score (LAZ) and mid-childhood body mass index (scenario A), and infant LAZ and mid-childhood intelligence quotient (scenario B). GA was a confounder that had a strong (scenario A) or weak (scenario B) association with the outcome. Compared with uncorrected postnatal age, using GA-corrected postnatal age attenuated the magnitude of associations, particularly in early infancy, and changed inferences for associations at birth. Although differences in the magnitude of associations were small when GA was weakly associated with the outcome, model fit was meaningfully improved using corrected postnatal age. When estimating population-averaged associations with early childhood growth in studies where preterm- and term-born children are included, incorporating heterogeneity in GA at birth in the age scale used to standardize anthropometric indices postnatally provides a useful strategy to reduce standardization errors.

Timing and Amount of Gestational Weight Gain in Association with Adverse Birth Outcomes

BACKGROUND

Most existing research on gestational weight gain and pregnancy outcomes has not accounted for timing of weight gain. The area under the weight gain curve (AUC) provides a single measure that incorporates both timing of weight gain and total amount gained. This study evaluated predictors and outcomes associated with second- and third-trimester weight gain AUC from the second and third trimester using time-to-event analysis to account for the correlation between gestational weight gain and gestational duration.

METHODS

Our prospective cohort study used data from the LifeCodes study at Brigham and Women's Hospital. Maternal weights were available from all prenatal and study visits. We used log-Poisson models with empirical variance estimation to identify predictors of total AUC from 14 weeks to delivery and Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between AUC quintile and adverse pregnancy outcomes.

RESULTS

Compared to the middle quintile, the highest quintile of accumulated pound-days was associated with a decreased hazard of spontaneous preterm birth among multigravid women (HR = 0.44; 95% CI = 0.23, 0.84), a decreased hazard of small-for-gestational-age births (HR = 0.65; 95% CI = 0.45, 0.92) overall and an increased hazard of large-for-gestational-age births among normal and underweight women (HR = 3.21; 95% CI = 1.50, 6.89) CONCLUSIONS:: In our study, a pattern of gestational weight gain characterized by more rapid gains earlier in pregnancy was associated with improved pregnancy outcomes in some subgroups of pregnant women.

Pre-pregnancy body dissatisfaction and weight-related outcomes and behaviors during pregnancy

To examine relationships among pre-pregnancy body dissatisfaction (BD) and gestational weight gain (GWG), and related attitudes/behaviors. Pre-pregnancy BD was self-reported in early pregnancy. Weight-related attitudes/behaviors were self-reported and physical activity was objectively measured during pregnancy. Overall, 92% of the women reported BD, with 69% desiring a smaller pre-pregnancy size than their actual pre-pregnancy size. Ideal pre-pregnancy weight was 20.7 ± 28 pounds less than self-reported pre-pregnancy weight. Only weight-control strategies used at 35 weeks were associated with BD (p = 0.008). Pre-pregnancy BD may not predict risk for excess GWG and some weight-related issues during pregnancy.

Consumption of ultra-processed foods in the third gestational trimester and increased weight gain: a Brazilian cohort study

Objective:

To investigate whether the consumption of ultra-processed foods (UPF) during pregnancy is associated with gestational weight gain (GWG).

Design:

Cohort study with collection of two 24-h dietary recalls during each gestational trimester obtained on non-consecutive days and differentiating weekday v. weekend/holiday. The foods were classified according to the NOVA system into fresh or minimally processed foods and their culinary preparations, processed and UPF and subsequently analysed as a percentage contribution to dietary energy. The outcome was average GWG in the second and in the third trimesters, expressed in g/week.

Setting:

Botucatu, a medium-sized Brazilian city.

Participants:

Pregnant women with regular obstetric risk (n 259) undergoing prenatal care in primary healthcare.

Results:

In a multiple linear regression model, it was found that an increase of 1 percentage point in energy consumption from UPF in the third gestational trimester led to an average increase of 4·17 (95 % CI 0·55; 7·79) g in weekly GWG in this period. There was no association between second-trimester UPF consumption and GWG.

Conclusions:

Consumption of UPF in the third gestational trimester is positively associated with average weekly GWG in this period.

The association of dietary glycaemic index and glycaemic load with gestational weight gain and newborn birth weight

Diet during pregnancy is related to several maternal and infant health outcomes; however, the relationship between maternal dietary glycaemic index (GI) and glycaemic load (GL) and gestational weight gain (GWG) or newborn birth weight is controversial. The purpose of the present study was to investigate the relationship between maternal dietary GI and GL and GWG and birth weight. A cohort of adult pregnant women with usual obstetric risk was followed in Botucatu, SP, Brazil. Two 24-h dietary recalls were collected in each gestational trimester (<14, 24-27, 31-34 weeks), one in person and the other by telephone. GI and GL were determined using the software Nutrition Data System for Research. GWG was obtained from medical records and evaluated as the weekly GWG between the second and third gestational trimesters. Newborn birth weight z-score in relation to gestational age was evaluated according to Intergrowth-21st Project recommendations. A multiple linear regression model, adjusted for potential confounders, showed a one-point increase in the GI resulted in a mean decrease of 12·9 (95 % CI -21·48, -4·24) g in weekly GWG; GL was not associated with this outcome. The birth weight z-score was not associated with GI (P = 0·763) or GL (P = 0·317). In conclusion, in a cohort of pregnant women considered at usual risk for obstetric complications, maternal dietary GI was negatively associated with weekly GWG in the second and third gestational trimesters. No association was observed between GL and GWG, and neither GI nor GL was associated with birth weight z-score.

Associations between prenatal diet quality and gestational weight gain

BACKGROUND

Improving prenatal diet quality may promote appropriate gestational weight gain (GWG).

AIM

To examine relationships between dietary quality in the second and third trimesters of pregnancy and GWG.

METHODS

Participants' (n = 41) dietary intake was assessed at 14-20 and 35 weeks gestation via the Automated Self-Administered 24-h recall (ASA-24). Kilocalories and Healthy Eating Index (HEI-2015) scores were calculated and associations with GWG were explored via linear regression.

RESULTS

Participants reported consuming 2139 ± 719 and 2085 ± 704 kilocalories at 18 and 35 weeks, respectively. HEI-2015 total scores at 18 (55.6 ±12.6) and 35 weeks gestation (56.6 ± 14.1) indicated a need for improvement. Greens and beans component score at 35 weeks was the only diet quality score associated with GWG.

CONCLUSIONS

GWG was not associated with most diet quality indices. However, vegetable intake may help to attenuate GWG. Future research should seek to elucidate relationships between GWG and dietary quality/intake to provide valuable insight for researchers and clinicians.

[Standard international recommendations for gestational weight gain: suitability for our population]

Introduction

Background: gestational weight gain (GWG) is one of the most commonly used indicators in prenatal care, and probably the most influential factor in perinatal outcomes. Objective: to determine the extent to which the GWG of pregnant women from the Ribera Health Department (Valencia) meets GWG international standards as recommended by the U.S. Institute of Medicine (IOM). Methods: a retrospective observational study of a sample of 4,361 women who gave birth at Hospital Universitario de la Ribera between January 1, 2010 and December 31, 2015. Pregnant women were classified according to GWG international recommendations: adequate weight gain, above and below. Results: a higher GWG increases the risk of cesarean delivery or instrumental delivery (OR = 1.454, p < 0.001; OR = 1.442, p < 0.001, respectively), and of having a macrosomic or larger newborn for gestational age (OR = 3.851, p = 0.008; OR = 1.749, p < 0.001, respectively) as compared to an appropriate GWG. GWG is related to birth weight (p < 0.001). Conclusions: the GPG recommendations issued by the IOM are generally well adapted to pregnant women in our environment. It has been found that a GPG other than these recommendations increases the probability of obtaining poor perinatal outcomes. Nevertheless, a more personalized approach is needed, adapting international recommendations to prenatal control for each of the pre-pregnancy BMI categories.

Accuracy of a mixed effects model interpolation technique for the estimation of pregnancy weight values

BACKGROUND

Interpolation of missing weight values is sometimes used in studies of gestational weight gain, but the accuracy of these methods has not been established. Our objective was to assess the accuracy of estimated weight values obtained by interpolating from the nearest observed weight values and by linear and spline regression models when compared with measured weight values.

METHODS

The study population included participants enrolled in the LIFECODES cohort at Brigham and Women's Hospital. We estimated weights at 28 (n=764) and 40 (n=382) weeks of gestation using participants' two nearest observed weights and subject-specific slopes and intercepts derived from repeated measures mixed effects models. In separate models, gestational age was parameterised as a linear and restricted cubic spline variable. Mean differences, absolute error measures and correlation coefficients comparing observed and estimated weights were calculated.

RESULTS

Mean differences and mean absolute error for weights derived from the 28-week linear model (0.18 lbs (SD 6.92), 2.73 lbs (SD 6.35)) and 40-week linear model (-0.40 lbs (SD 5.43) and 2.84 lbs (SD 4.65)) were low. Mean differences were somewhat greater at 28 weeks for weight values derived from the nearest two observed values (mean difference -1.97 lbs (SD 8.74)) and from spline models (mean difference -2.25 lbs (SD 7.13)). Results were similar at 40 weeks.

CONCLUSIONS

Overall, weight values estimated using this interpolation approach showed good agreement with observed values. When repeated measures of weight are available, mixed effects models may be used to interpolate of missing weight values with minimal error.

Association of Weight for Length vs Body Mass Index During the First 2 Years of Life With Cardiometabolic Risk in Early Adolescence

Importance

The American Academy of Pediatrics currently recommends weight for length (WFL) for assessment of weight status in children younger than 2 years but body mass index (BMI) for children older than 2 years. However, the clinical implications of using WFL vs BMI in children younger than 2 years as an indicator of future health outcomes remains understudied.

Objective

To compare associations of overweight based on WFL vs BMI in children younger than 2 years with cardiometabolic outcomes during early adolescence.

Design, Setting, and Participants

This prospective study of birth cohorts in the United States (Project Viva) and Belarus (Promotion of Breastfeeding Intervention Trial [PROBIT]) performed from June 1, 1996, to November 31, 2002, included 13 666 children younger than 2 years.

Main Exposures

Overweight defined as Centers for Disease Control and Prevention (CDC) WFL in the 95th percentile or greater, World Health Organization (WHO) WFL in the 97.7th percentile or greater, or WHO BMI in the 97.7th percentile or greater at 6, 12, 18, or 24 months of age.

Main Outcomes and Measures

Primary outcomes were fat mass index, insulin resistance, metabolic risk score, and obesity during early adolescence. Secondary outcomes were height and BMI z scores, sum of skinfolds, waist circumference, and systolic blood pressure during early adolescence.

Results

The study included 919 children (mean [SD] age, 12.9 [0.9] years; 460 [50.1%] male; and 598 [65.1%] white) from Project Viva and 12 747 children (mean [SD] age, 11.5 [0.5] years; 6204 [48.7%] male; and 12 747 [100%] white) from PROBIT. During 6 to 24 months of age, in Project Viva, 206 children (22.4%) were overweight at any of the 4 times points according to the CDC WFL, 160 (17.4%) according to WHO WFL, and 161 (17.5%) according to WHO BMI cut points. In PROBIT, 3715 children (29.1%) were overweight at any of the 4 time points according to the CDC WFL, 3069 (24.1%) according to WHO WFL, and 3125 (24.5%) according to WHO BMI cut points. After maternal and child characteristics were adjusted for, being ever overweight (vs never overweight) during 6 to 24 months of age was associated with higher likelihood of adverse cardiometabolic risk markers during early adolescence, but associations did not differ substantially across WFL and BMI cut points in either cohort. For example, for fat mass index in Project Viva, β = 0.9 (95% CI, 0.5-1.4) for the CDC WFL, β = 1.1 (95% CI, 0.6-1.6) for WHO WFL, and β = 1.4 (95% CI, 0.9-1.9) for WHO BMI. For PROBIT, β = 0.5 (95% CI, 0.4-0.6) for the CDC WFL, β = 0.6 (95% CI, 0.5-0.7) for WHO WFL, and β = 0.6 (95% CI, 0.5-0.6) for WHO BMI. Neither growth metric in infancy was superior over the others based on F statistics (Project Viva: 17.1-17.8; PROBIT: 87.1-88.7). Findings were similar for insulin resistance, metabolic risk score, obesity, and secondary outcomes.

Conclusions and Relevance

Choice of WFL vs BMI to define overweight during the first 2 years of life may not greatly affect the association with cardiometabolic outcomes during early adolescence. The findings appear to have important implications for investigators seeking to use BMI as a growth metric for epidemiologic research and for practitioners monitoring the weight status of children younger than 2 years.

Beverage Intake During Pregnancy and Childhood Adiposity

OBJECTIVES

To examine associations of sugar sweetened beverages (SSBs) and other beverage intake during pregnancy with adiposity in midchildhood (median age of 7.7 years).

METHODS

We studied 1078 mother-child pairs in Project Viva, a prospective prebirth cohort study. Exposures were sugary and nonsugary beverage intake assessed in the first and second trimesters of pregnancy by using a food frequency questionnaire. Main outcome measures were offspring overall adiposity (BMI z score, fat mass index [FMI, kg/m²] from dual-energy radiograph absorptiometry, and sum of subscapular [SS] and triceps [TR] skinfold thicknesses) and central adiposity (SS:TR ratio and waist circumference).

RESULTS

In the second trimester, mean (SD) SSB intake was 0.6 (0.9) servings per day. Thirty-two percent of mothers were multiracial or people of color, 68% were college graduates, and 10% smoked during pregnancy. In midchildhood, mean (SD) BMI z score was 0.38 (1.00), and the FMI was 4.4 (1.9) kg/m². In multivariable models adjusted for multiple maternal and child covariates, each additional serving per day of SSB was associated with higher BMI z scores (0.07 U; 95% confidence interval [CI]: -0.01 to 0.15), FMI (0.15 kg/m²; 95% CI: -0.01 to 0.30), SS + TR (0.85 mm; 95% CI: 0.06 to 1.64), and waist circumference (0.65 cm; 95% CI: 0.01 to 1.28). Stratified models suggested that the associations were due primarily to maternal, not child, SSB intake and to sugary soda rather than fruit drinks or juice. We did not find differences between boys and girls, nor did we observe the effects of sugar-free soda or of first-trimester beverage intake.

CONCLUSIONS

Higher SSB intake during the second trimester of pregnancy was associated with greater adiposity in midchildhood.

Higher Maternal Protein Intake during Pregnancy Is Associated with Lower Cord Blood Concentrations of Insulin-like Growth Factor (IGF)-II, IGF Binding Protein 3, and Insulin, but Not IGF-I, in a Cohort of Women with High Protein Intake

Background: Prenatal exposure to dietary protein may program growth-regulating hormones, consequently influencing early-life growth patterns and later risk of associated chronic diseases. The insulin-like growth factor (IGF) axis is of particular interest in this context given its influence on pre- and postnatal growth and its sensitivity to the early nutritional environment.Objective: Our objective was to examine associations of maternal protein intake during pregnancy with cord blood concentrations of IGF-I, IGF-II, IGF binding protein-3 (IGFBP-3), and insulin.Methods: We studied 938 mother-child pairs from early pregnancy through delivery in the Project Viva cohort. Using multivariable linear regression models adjusted for maternal race/ethnicity, education, income, smoking, parity, height, and gestational weight gain and for child sex, we examined associations of second-trimester maternal protein intake [grams per kilogram (weight before pregnancy) per day], as reported on a food frequency questionnaire, with IGF-I, IGF-II, IGFBP-3, and insulin concentrations in cord blood. We also examined how these associations may differ by child sex and parity.Results: Mothers were predominantly white (71%), college-educated (64%), and nonsmokers (67%). Mean ± SD protein intake was 1.35 ± 0.35 g ⋅ kg^-1 ⋅ d^-1 Each 1-SD increment in second-trimester protein intake corresponded to a change of -0.50 ng/mL (95% CI: -2.26, 1.26 ng/mL) in IGF-I and -0.91 μU/mL (95% CI: -1.45, -0.37 μU/mL) in insulin. Child sex and parity modified associations of maternal protein intake with IGF-II and IGFBP-3: protein intake was inversely associated with IGF-II in girls (P-interaction = 0.04) and multiparous mothers (P-interaction = 0.05), and with IGFBP-3 in multiparous mothers (P-interaction = 0.04).Conclusions: In a cohort of pregnant women with relatively high mean protein intakes, higher intake was associated with lower concentrations of growth-promoting hormones in cord blood, suggesting a pathway that may link higher protein intake to lower fetal growth. This trial was registered at clinicaltrials.gov as NCT02820402.

Helicobacter Infection Significantly Alters Pregnancy Success in Laboratory Mice

Helicobacter spp. are gram-negative, helically shaped bacteria that cause gastric and enterohepatic infections in mammalian species. Although Helicobacter infection frequently is implicated to interfere with reproductive success, few experimental data support these claims. We therefore retrospectively investigated the effect of Helicobacter infection on murine pregnancy outcome after the identification of endemic Helicobacter infection in an animal research facility. Multiplex conventional PCR analysis was used to characterize Helicobacter infection status in one inbred and 2 transgenic strains of mice in 2 self-contained rooms assigned to the same investigator. Outcomes of timed-mating experiments were compared among Helicobacter spp.-infected and uninfected mice of the same strain; Helicobacter infection was eradicated from the colony through fostering with uninfected dams. Although Helicobacter infection affected fecundity in only one strain of transgenic mouse, the total number of embryos per gravid uterus was significantly reduced in C57BL/6J mice that were infected with a single Helicobacter species, H. typhlonius. Helicobacter infection was also associated with a significant increase in the number of resorbing embryos per uterus and significant decreases in pregnancy-associated weight gain relative to uninfected mice in C57BL6/J mice and one transgenic strain. Helicobacter spp.-infected mice of all tested strains exhibited higher frequency of intrauterine hemorrhaging relative to uninfected mice. These results indicate that naturally-acquired Helicobacter infection not only reduces the productivity of a research animal breeding colony, but also negatively impacts embryo health. Despite these deleterious effects, these data suggest that colonies can be rederived to be Helicobacter-free by Cesarean section and fostering with uninfected dams. This paper provides the first evidence that H. typhlonius infection is sufficient to interfere with reproductive success and embryo health of C57BL/6J mice. Animal research facilities should therefore implement Helicobacter spp. surveillance and control practices to avoid confounding experimental results and to improve breeding colony efficiency.

First and second trimester gestational weight gains are most strongly associated with cord blood levels of hormones at delivery important for glycemic control and somatic growth

BACKGROUND

Excessive gestational weight gain (GWG) during pregnancy is associated with adverse outcomes for mothers and offspring. Early, mid, and late pregnancy GWGs have different associations with fetal growth and later life adiposity, but associations with cord blood hormones, which might predict later health, are not well studied.

METHODS

In 978 pregnant women from the pre-birth Project Viva cohort, we calculated trimester-specific GWG using clinically recorded prenatal weights. Outcomes were levels of umbilical cord blood hormones related to fetal and postnatal growth. We used linear regression models adjusted for maternal race/ethnicity, pre-pregnancy BMI, parity, education, pregnancy smoking status and child sex; 2nd and 3rd trimester models were additionally adjusted for GWG in prior trimesters.

RESULTS

Mean±SD pre-pregnancy BMI was 24.9±5.5kg/m², 30% were non-white, and 63% were college graduates. Mean±SD cord blood hormone levels were insulin-like growth factor [IGF]-1 (56.4±24.3ng/mL), IGF-2 (408.5±92.7ng/mL), IGFBP-3 (1084±318ng/mL), insulin (6.5±7.2 uU/mL), C-peptide (1.0±0.6ng/mL), leptin (9.0±6.6ng/mL) and adiponectin (28.7±6.8μg/mL). Mean±SD 1st, 2nd and 3rd trimester GWG rates were 0.22±0.22, 0.49±0.19 and 0.46±0.22kg/wk. Greater 1st trimester GWG (per 0.2kg/wk) was associated with higher insulin (0.5 uU/mL; 95% CI 0.1, 0.9) and C-peptide (0.06ng/mL; 95% CI 0.02, 0.09) and lower adiponectin (-0.4μg/mL; 95% CI -0.9, 0.0). Greater 2nd trimester GWG (per 0.2kg/wk) was associated with higher IGF-1 (2.3ng/mL; 95% CI 0.6, 4.0), IGF-2 (7.9ng/mL; 95% CI 1.2, 14.6), IGFBP-3 (41.6ng/mL; 95% CI 19.4, 63.7) and leptin (0.9ng/mL; 0.4, 1.4). 3rd trimester GWG was not associated with cord blood hormones.

CONCLUSION

1st trimester weight gain appears to matter more for cord blood hormones related to offspring glucose/insulin regulation, whereas 2nd trimester gain matters more for hormones related to growth and adiposity.

Classifying Gestational Weight Gain Trajectories Using the SITAR Growth Model

BACKGROUND

Gestational weight gain is often characterized by the total amount of weight gained during pregnancy, however, the pattern of gain may be an important determinant of health outcomes. The SITAR (Super Imposition by Translation And Rotation) model has been used to describe childhood growth trajectories and has appeal because of the biological interpretability of its parameters. The objective of this study was to determine the feasibility of applying this model to gestational weight gain trajectories.

METHODS

The study cohort included 3470 normal-weight, overweight, and obese women delivering at Magee-Womens Hospital in Pittsburgh, Pennsylvania, 1998 to 2010. We applied the SITAR model, a non-linear mixed effects model, to serial prenatal weight gain measurements in each pre-pregnancy body mass index (BMI) category. We fit models of varying complexity, and chose the best-fitting model to describe the pattern of weight gain (by its absolute amount, timing, and acceleration) for each BMI group.

RESULTS

The most complex SITAR models failed to converge, but reduced models could successfully be fit by specifying fewer random effects and simplifying the modelling of gestational age. Best-fitting models for each BMI group explained between 95% and 97% of the variation in weight gain trajectories. Peak rates of weight gain were reached between the 20th and 22nd weeks, and were higher for normal and overweight women (0.59 kg/week and 0.57 kg/week, respectively) than obese women (0.46 kg/week).

CONCLUSIONS

Following some modifications, the SITAR model can be used to characterize pregnancy weight gain patterns.

Sex-Specific Associations of Maternal Gestational Glycemia with Hormones in Umbilical Cord Blood at Delivery

Background Few studies have examined sex-specific associations of maternal gestational glycemia with cord blood hormones, which might predict later health. Methods In 976 women without pre-existing diabetes in the Project Viva cohort, we used linear regression to examine associations of maternal gestational glycemia with cord hormone concentrations, adjusted for maternal characteristics and stratified by infant sex. Results A total of 6.1% of women had gestational diabetes mellitus (GDM), 8.8% isolated hyperglycemia, 3.2% gestational impaired glucose tolerance, and 81.9% were normoglycemic. In boys, compared with infants of normoglycemic mothers, infants of GDM mothers had higher cord levels of IGF-2 (β 35.55 ng/mL; 95% CI: 2.60, 68.50), IGFBP-3 (111.2 ng/mL; 5.53, 216.8), insulin (4.66 uU/mL; 2.38, 6.95), C-peptide (0.46 ng/mL; 0.25, 0.67), and leptin (3.51 ng/mL; 1.37, 5.64), but lower IGF-1 (-6.71 ng/mL; -12.7, - 0.76, adjusted for IGFBP-3). In girls, GDM offspring had higher cord blood levels of IGF-1 adjusted for IGFBP-3 (12.45 ng/mL; 4.85, 20.04). Boys, but not girls, of mothers with abnormal glucose tolerance but not GDM also had higher levels of some hormones. Conclusion GDM was associated with growth factors and adipokines in cord blood from boys, but only IGF-1 in girls. These findings suggest sex differences in responses to fetal overnutrition.

Pre-Pregnancy Maternal Exposure to Persistent Organic Pollutants and Gestational Weight Gain: A Prospective Cohort Study

Persistent organic pollutants (POPs) have been implicated in the development of obesity in non-pregnant adults. However, few studies have explored the association of POPs with gestational weight gain (GWG), an important predictor of future risk of obesity in both the mother and offspring. We estimated the association of maternal pre-pregnancy levels of 63 POPs with GWG. Data are from women (18-40 years; n = 218) participating in a prospective cohort study. POPs were assessed using established protocols in pre-pregnancy, non-fasting blood samples. GWG was assessed using three techniques: (1) total GWG (difference between measured pre-pregnancy weight and final self-reported pre-delivery weight); (2) category based on pre-pregnancy body mass index (BMI)-specific Institute of Medicine (IOM) recommendations; and (3) area under the GWG curve (AUC). In an exploratory analysis, effects were estimated separately for women with BMI < 25 kg/m² versus BMI ≥ 25 kg/m². Multivariable polytomous logistic regression and linear regression were used to estimate the association between each chemical or congener and the three GWG outcomes. p,p'-dichlorodiphenyl trichloroethane (p,p'-DDT) was significantly inversely associated with AUC after adjustment for lipids and pre-pregnancy BMI: beta {95% confidence interval (CI)}, -378.03 (-724.02, -32.05). Perfluorooctane sulfonate (PFOS) was significantly positively associated with AUC after adjustment for lipids among women with a BMI < 25 kg/m² {beta (95% CI), 280.29 (13.71, 546.86)}, but not among women with a BMI ≥ 25 kg/m² {beta (95% CI), 56.99 (-328.36, 442.34)}. In summary, pre-pregnancy levels of select POPs, namely, p,p'-DDT and PFOS, were moderately associated with GWG. The association between POPs and weight gain during pregnancy may be more complex than previously thought, and adiposity prior to pregnancy may be an important effect modifier.

Educational Attainment and Gestational Weight Gain among U.S. Mothers

BACKGROUND

Education is an important social determinant of many health outcomes, but the relationship between educational attainment and the amount of weight gained over the course of a woman's pregnancy (gestational weight gain [GWG]) has not been established clearly.

METHODS

We used data from 1979 through 2010 for women in the National Longitudinal Survey of Youth (1979) cohort (n = 6,344 pregnancies from 2,769 women). We used generalized estimating equations to estimate the association between educational attainment and GWG adequacy (as defined by 2009 Institute of Medicine guidelines), controlling for diverse social factors from across the life course (e.g., income, wealth, educational aspirations and expectations) and considering effect measure modification by race/ethnicity and prepregnancy overweight status.

RESULTS

In most cases, women with more education had increased odds of gaining a recommended amount of gestational weight, independent of educational aspirations and educational expectations and relatively robust to sensitivity analyses. This trend manifested itself in a few different ways. Those with less education had higher odds of inadequate GWG than those with more education. Among those who were not overweight before pregnancy, those with less education had higher odds of excessive GWG than college graduates. Among women who were White, those with less than a high school degree had higher odds of excessive GWG than those with more education.

CONCLUSION

The relationship between educational attainment and GWG is nuanced and nonlinear.

Trajectories of maternal gestational weight gain and child cognition assessed at 5 years of age in a prospective cohort study

BACKGROUND

There has been concern that low gestational weight gain may cause poor fetal neurodevelopment.

METHODS

The association between maternal weight gain and child IQ was examined using serial antenatal weight measurements (median 12) from a prospective cohort of non-obese Scandinavian women (1986-1988). Linear mixed models with piecewise regression were used to estimate participants' (n=552) trimester-specific average rate of weight gain. Linear regression was used to assess the association between weight gain and children's (n=344) full-scale, performance and verbal IQ measured at age 5 using the Wechsler Preschool and Primary Scales of Intelligence-Revised.

RESULTS

Children born to mothers who gained below versus within the 2nd trimester 2009 recommendations tended to have lower IQ scores (Full-scale: 106.6 (SD 15.1) vs 110.2 (15.2), p=0.04; verbal: 102.5 (14.3) vs 105.0 (14.9), p=0.10; performance: 109.5 (15.4) vs 113.4 (14.5), p=0.03). After adjustment there were no differences in child IQ by weight gain adequacy (full-scale: βbelow=-1.1 (95% CI -5.1 to 2.9), βabove=1.5 (-3.8 to 6.8); verbal: βbelow=-0.2 (-3.1 to 2.6), βabove=1.8 (-3.6 to 7.3); performance βbelow=-1.2 (-4.6 to 2.2), βabove=1.0 (-4.6 to 6.7)). No differences were observed based on 3rd trimester adequacy. No differences were observed in IQ scores by quintile of weight gain for any trimester, particularly after adjustment for maternal IQ.

CONCLUSIONS

Our findings are reassuring that among normal weight women, pregnancy weight gain is not associated with child cognitive development. Further investigation should be conducted in contemporary cohorts that also include obese mothers, who are at the greatest risk for low weight gain.

Maternal obesity in Africa: a systematic review and meta-analysis

Background

Maternal obesity is emerging as a public health problem, recently highlighted together with maternal under-nutrition as a ‘double burden’, especially in African countries undergoing social and economic transition. This systematic review was conducted to investigate the current evidence on maternal obesity in Africa.

Methods

MEDLINE, EMBASE, Scopus, CINAHL and PsycINFO were searched (up to August 2014) and identified 29 studies. Prevalence, associations with socio-demographic factors, labour, child and maternal consequences of maternal obesity were assessed. Pooled risk ratios comparing obese and non-obese groups were calculated.

Results

Prevalence of maternal obesity across Africa ranged from 6.5 to 50.7%, with older and multiparous mothers more likely to be obese. Obese mothers had increased risks of adverse labour, child and maternal outcomes. However, non-obese mothers were more likely to have low-birthweight babies. The differences in measurement and timing of assessment of maternal obesity were found across studies. No studies were identified either on the knowledge or attitudes of pregnant women towards maternal obesity; or on interventions for obese pregnant women.

Conclusions

These results show that Africa's levels of maternal obesity are already having significant adverse effects. Culturally adaptable/sensitive interventions should be developed while monitoring to avoid undesired side effects.

Associations of trimester-specific gestational weight gain with maternal adiposity and systolic blood pressure at 3 and 7 years postpartum

OBJECTIVE

Our objective was to examine the associations of total and trimester-specific gestational weight gain (GWG) rate with postpartum maternal weight and cardiometabolic risk. We hypothesized that first-trimester GWG would be most strongly associated with long-term maternal health.

STUDY DESIGN

We studied 801 women enrolled during the first trimester of pregnancy in the Boston-area Project Viva cohort 1999 through 2002. At 3 years postpartum we measured maternal weight, waist circumference (WC), and systolic blood pressure (SBP) and collected fasting blood from a subset. At 7 years postpartum we again measured weight and WC. We used multivariable linear regression to evaluate relations of total and trimester-specific GWG rate with weight change (vs self-reported prepregnancy weight) and WC at each time point, stratified by prepregnancy weight, as well as associations with SBP and insulin resistance at 3 years.

RESULTS

Median age at enrollment was 34.0 years (range, 16.4-44.9); 65% were white. Mean (SD) total GWG rate was 0.38 (0.14) kg/wk. Women gained weight faster during the second (0.47 [0.19] kg/wk) and third (0.44 [0.22] kg/wk) trimesters than the first (0.22 [0.22] kg/wk). Total and first-trimester GWG rate were most strongly associated with postpartum weight change. Among normal-weight women, each 1-SD increase in total and first-trimester GWG rate corresponded with 0.85 (95% confidence interval [CI], 0.07-1.63) kg and 2.08 (1.32-2.84) kg greater weight change at 3 and 7 years postpartum, respectively, but there was not strong evidence of association for either second- (-0.30 kg; 95% CI, -1.08 to 0.48) or third- (-0.26 kg; 95% CI, -1.08 to 0.55) trimester GWG. First-trimester GWG rate also related to 3-year postpartum weight change in overweight (2.28 kg; 95% CI, 0.95-3.61) and obese (2.47 kg; 95% CI, 0.98-3.97) women. Greater total and first-trimester GWG rate were associated with larger WC and higher SBP but not insulin resistance.

CONCLUSION

In this observational cohort, first-trimester weight gain was more strongly associated with maternal weight retention as well as higher WC and blood pressure than second- or third-trimester gain. Interventions targeting GWG beginning very early in pregnancy may benefit long-term maternal health.

Weight gain in pregnancy and application of the 2009 IOM guidelines: toward a uniform approach

OBJECTIVE

There is an urgent need to adopt standardized nomenclature as it relates to gestational weight gain (GWG), a more uniform approach to calculate it, and hence quantifying adherence to the 2009 Institute of Medicine (IOM) guidelines.

METHODS

This perspective highlights the varying methods used to estimate GWG and discuss the advantages and limitations of each.

RESULTS

While these calculations could be argued to have a minimal impact on data at the population level, on the patient level, incorrectly estimating weight at conception can result in misclassification of preconception body mass index (BMI) and assignment of the IOM guidelines which inherently affect the prospective management of weight gain (and potential outcomes) during the current pregnancy.

CONCLUSIONS

This study recommends that preconception BMI and total GWG be determined objectively and total GWG be adjusted for length of gestation before assessing adherence to the IOM GWG guidelines.

Gestational weight gain and exposure of newborns to persistent organic pollutants

BACKGROUND

Exposure to persistent organic pollutants (POPs) during fetal development can increase the risk of adverse health effects during childhood. Maternal characteristics and physiological changes during gestation, such as gestational weight gain (GWG), may have an influence in the overall burden of POPs in neonates. However, the associations between GWG and POP concentrations are still not well established.

OBJECTIVE

We examined the association of GWG with cord serum POPs concentrations after adjusting for prepregnancy maternal body mass index (BMI) and other potential determinants of the transfer of POPs into newborns. The GWG values were evaluated after grouping by the reference guidelines of the Institute of Medicine (IOM).

METHODS

We measured levels of 14 organochlorine pesticides, 7 polychlorobiphenyls (PCBs), and 14 polybrominated diphenyl ethers (PBDEs) in 325 cord serum samples from a Spanish birth cohort. Multivariable models were used to estimate associations of GWG, prepregnancy BMI, and other maternal determinants on cord serum concentrations of POPs.

RESULTS

Neonatal concentrations of POPs were inversely associated with GWG after adjustment for age, prepregnancy BMI, educational level, and fish consumption. On average, neonates of women with IOM-recommended GWG have lower POP concentrations than do neonates of mothers with inadequate GWG.

CONCLUSIONS

The present findings suggest an association between neonatal exposure to POPs and inadequate GWG during pregnancy. Encouraging pregnant women to meet the recommended IOM guidelines for GWG may reduce the accumulation of POPs in newborns.

Gestational weight gain and neonatal adiposity in the Hyperglycemia and Adverse Pregnancy Outcome study-North American region

OBJECTIVE

To examine the associations between gestational weight gain (GWG) exceeding Institute of Medicine (IOM) guidelines and neonatal adiposity in the five North American field centers of the Hyperglycemia and Adverse Pregnancy Outcome study.

METHODS

GWG was categorized as less than, within, or greater than 2009 IOM guidelines. Birthweight, body fat percentage, cord serum C-peptide, and sum of neonatal flank, subscapular, and triceps skin fold thicknesses were dichotomized as >90th percentile or ≤90th percentile obtained by quantile regression. Logistic regression analysis was used.

RESULTS

Of the 5297 participants, 11.6% gained less, 31.9% gained within, and 56.5% gained more than the recommendation. With adjustment for glucose tolerance levels, normal and overweight women who gained more than the recommendation had increased odds of delivering infants with sum of skin folds >90th percentile (OR = 1.75 and 4.77, respectively) and percentage body fat >90th percentile (OR = 2.41 and 2.59, respectively), and normal weight and obese women who gained more than the recommendation had increased odds of delivering infants with birthweight >90th percentile (OR = 2.80 and 1.93, respectively) compared to women who gained within the recommendation.

CONCLUSIONS

This analysis showed independent associations between exceeding IOM GWG recommendations and neonatal adiposity in normal and overweight women, controlling for glucose tolerance levels.

Should obese women gain less weight in pregnancy than recommended?

BACKGROUND

Previous research on inadequate gestational weight gain among obese women and adverse outcomes has been mixed. The objective of this study was to examine associations between inadequate gain among obese women and antepartum, intrapartum, and infant outcomes.

METHODS

Obese women from the U.S. Collaborative Perinatal Project were divided into obesity classes I (30.0-34.9 kg/m(2)) and II/III (> 35.0 kg/m(2)) and three weight gain categories (inadequate: < 5 kg, adequate: 5-9 kg, excessive: > 9 kg) as defined by the U.S. Institute of Medicine. Associations between 1-kg increments of inadequate gain (< 5 kg) and outcomes were examined. Women with inadequate gain were also compared with women gaining normal (5-9 kg) and excessive (> 9 kg) weight.

RESULTS

Each fewer 1-kg of weight gain increased small-for-gestational age (SGA) risk and reduced large-for-gestational age (LGA) risk by similar magnitude. Compared with excessive gain, inadequate gain reduced the odds of preeclampsia (OR: 0.56, CI: 0.37, 0.84), gestational hypertension (OR: 0.66, CI: 0.47, 0.92), and LGA (OR: 0.48, CI: 0.38, 060) and increased the odds of SGA (OR: 2.26, CI: 1.52, 3.35). Inadequate gain offered fewer advantages over adequate weight gain: lower odds of LGA (OR: 0.75, CI: 0.57, 0.99); increased odds of SGA (OR: 1.86, CI: 1.18, 2.91). Most associations applied to obesity class I but not class II/III women.

CONCLUSIONS

Inadequate weight gain poses benefits and risks to mothers and infants, but is preferable to excessive gain. The risks and benefits apply differently to class I versus class II/III obese women, indicating the need for weight gain recommendations by obesity class.

An investigation into utilising gestational body mass index as a screening tool for adverse birth outcomes and maternal morbidities in a group of pregnant women in Khayelitsha

OBJECTIVE

The aim of this study was to investigate the ability of the gestational body mass index (BMI) method to screen for adverse birth outcomes and maternal morbidities.

DESIGN

This was a substudy of a randomised controlled trial, the Philani Mentor Mothers' study.

SETTING AND SUBJECTS

The Philani Mentor Mothers' study took place in a peri-urban settlement, Khayelitsha, between 2009 and 2010. Pregnant women living in the area in 2009-2010 were recruited for the study.

OUTCOME MEASURES

Maternal anthropometry (height and weight) and gestational weeks were obtained at baseline to calculate the gestational BMI, which is maternal BMI adjusted for gestational age. Participants were classified into four gestational BMI categories: underweight, normal, overweight and obese. Birth outcomes and maternal morbidities were obtained from clinic cards after the births.

RESULTS

Pregnant women were recruited into the study (n = 1 058). Significant differences were found between the different gestational BMI categories and the following birth outcomes: maternal (p-value = 0.019), infant hospital stay (p-value = 0.03), infants staying for over 24 hours in hospital (p-value = 0.001), delivery mode (p-value = 0.001), birthweight (p-value = 0.006), birth length (p-value = 0.007), birth head circumference (p-value = 0.007) and pregnancy-induced hypertension (p-value = 0.001).

CONCLUSION

To the best of our knowledge, this is the first study that has used the gestational BMI method in a peri-urban South African pregnant population. Based on the findings that this method is able to identify unfavourable birth outcomes, it is recommended that it is implemented as a pilot study in selected rural, peri-urban and urban primary health clinics, and that its ease and effectiveness as a screening tool is evaluated. Appropriate medical and nutritional advice can then be given to pregnant women to improve both their own and their infants' birth-related outcomes and maternal morbidities.

Fibre intake and evolution of BMI: from pre-pregnancy to postpartum

Objective

To evaluate the effect of fibre intake on the evolution of maternal BMI from pregnancy to postpartum and to identify dietary patterns associated with fibre intake.

Design

Cohort study. Food intake was obtained using an FFQ. Focused principal component analysis was used focusing on the variables: postpartum weight retention and total dietary fibre intake. Poisson regression models with robust variance were built in order to measure the effect of fibre intake during the postpartum period on obesity risk.

Setting

Primary care clinics in southern Brazil.

Subjects

Pregnant women (n370) were followed until the 5th month postpartum.

Results

The highest contribution to fibre intake came from the consumption of beans. Consumption of bread and rice indicated a common Brazilian food pattern along with beans. Participants retained a median of 4·4 (interquartile range 0·6, 7·9) kg of weight gained during pregnancy. Obesity risk, defined as an unfavourable evolution of BMI during pregnancy and postpartum, was present in 189 (55·1 %) women. Individual food items did not have an important effect on weight retention. In Poisson regression adjusting for maternal age, pre-pregnancy BMI and total gestational weight gain, inadequate postpartum fibre intake increased obesity risk by 24 % (relative risk = 1·24; 95 % CI 1·05, 1·47).

Conclusions

Important maternal weight retention occurred in these women. Adequate fibre intake may reduce obesity risk in the period following childbirth.

Mediating effects of body image satisfaction on exercise behavior, depressive symptoms, and gestational weight gain in pregnancy

BACKGROUND

Body image satisfaction in pregnancy may have an important influence on maternal biopsychosocial outcomes.

PURPOSE

This study aims to examine the mediating influence of trimesters 2 and 3 body image satisfaction on trimesters 2 and 3 depressive symptoms, exercise behavior, and gestational weight gain.

METHODS

Pregnant women (N = 151; mean age = 30) prospectively completed study measures via mail during their 1st, 2nd, and 3rd trimesters.

RESULTS

As predicted, trimesters 2 and 3 body image satisfaction mediated the relationship between trimester 1 body image satisfaction and trimester 2 depressive symptoms and the relationship between trimester 2 body image satisfaction and trimester 3 depressive symptoms. In contrast to the hypothesis, no mediation was observed for the relationship between body image satisfaction and exercise behavior or gestational weight gain.

CONCLUSIONS

These preliminary findings demonstrate that body image satisfaction is an important psychological determinant of depressive symptoms in pregnancy. Promoting healthy body image may be a non-pharmacological strategy that offers protective effects against depressive symptoms during pregnancy.

Prepregnancy body mass index and gestational weight gain in relation to child body mass index among siblings

There is increasing evidence that in utero effects of excessive gestational weight gain may result in increased weight in children; however, studies have not controlled for shared genetic or environmental factors between mothers and children. Using 2,758 family groups from the Collaborative Perinatal Project, the authors examined the association of maternal prepregnancy body mass index (BMI) and gestational weight gain on child BMI at age 4 years using both conventional generalized estimating equations and fixed-effects models that account for shared familial factors. With generalized estimating equations, prepregnancy BMI and gestational weight gain had similar associations with the child BMI z score (β = 0.09 units, 95% confidence interval (CI): 0.08, 0.11; and β = 0.07 units, 95% CI: 0.04, 0.11, respectively. However, fixed effects resulted in null associations for both prepregnancy BMI (β = 0.03 units, 95% CI: -0.01, 0.07) and gestational weight gain (β = 0.03 units, 95% CI: -0.02, 0.08) with child BMI z score at age 4 years. The positive association between gestational weight gain and child BMI at age 4 years may be explained by shared family characteristics (e.g., genetic, behavioral, and environmental factors) rather than in utero programming. Future studies should continue to evaluate the relative roles of important familial and environmental factors that may influence BMI and obesity in children.

Higher infant body fat with excessive gestational weight gain in overweight women

OBJECTIVE

Gestational weight gain (GWG) is positively associated with birthweight and maternal prepregnancy body mass index (BMI) is directly related to infant fat mass (FM). This study examined whether differences exist in infant body composition based on 2009 GWG recommendations.

STUDY DESIGN

Body composition was measured in 306 infants, and GWG was categorized as appropriate or excessive. Analysis of covariance was used to investigate the effects of GWG and prepregnancy BMI and their interaction on infant body composition.

RESULTS

Within the appropriate group, infants from obese mothers had greater percent fat (%fat) and FM than offspring from normal and overweight mothers. Within the excessive group, infants from normal mothers had less %fat and FM than infants from overweight and obese mothers. A difference was found for %fat and FM within the overweight group between GWG categories.

CONCLUSION

Excessive GWG is associated with greater infant body fat and the effect is greatest in overweight women.

Socioeconomic, demographic and nutritional factors associated with maternal weight gain in general practices in Southern Brazil

In order to describe adequacy of weight gain during pregnancy and its association with pre-pregnancy nutritional status and other factors, a cohort study of pregnant women enrolled at 16-36 weeks of gestation and followed up until delivery was carried out in prenatal care in primary care services in Rio Grande do Sul State, Brazil. Maternal weight was recorded at each prenatal care visit. Weight gain was classified as "adequate," "insufficient" or "excessive" (Institute of Medicine). Poisson regression was used to measure the associations. The sample was comprised of 667 women, and insufficient and excessive weight gain incidences were 25.8% and 44.8%, respectively. Overweight and obese before pregnancy had a significant increased risk of excessive weight gain in pregnancy (RR: 1.75; 95%CI: 1.48-2.07, RR: 1.55; 95%CI: 1.23-1.96, respectively). Women with fewer than six prenatal visits had a 52% increased risk for weight gain below recommended values. Although insufficient weight gain may still be a public health problem, excessive gain is becoming a concern that needs immediate attention in prenatal care.

Physical activity and gestational weight gain: a meta-analysis of intervention trials

BACKGROUND

high gestational weight gain (GWG) has been found to be associated with a number of adverse perinatal and long-term outcomes.

OBJECTIVES

we aimed to perform a systematic review and meta-analysis to find out whether physical activity in pregnancy might help avoid high GWG.

SEARCH STRATEGY

a literature search in relevant databases and an additional search by hand through bibliographies of various publications were performed.

SELECTION CRITERIA

we included randomised controlled trials on healthy women, with increased physical activity as the only intervention. GWG had to be documented for the intervention and control group separately.

DATA COLLECTION AND ANALYSIS

two reviewers independently extracted data and performed quality assessment. Data from the included trials were combined using a random-effects model. The effect size was expressed as mean difference (MD).

MAIN RESULTS

of 1380 studies identified, 12 trials met the inclusion criteria. In seven trials, GWG was lower in the exercise group compared with the control group, whereas five trials showed a lower GWG in the control groups. The meta-analysis resulted in an MD of GWG of -0.61 (95% CI: -1.17, -0.06), suggesting less GWG in the intervention groups compared with the control groups. We found no indication for publication bias or dose effects.

AUTHOR'S CONCLUSIONS

in summary, our analyses suggest that physical activity during pregnancy might be successful in restricting GWG.

A preliminary study on the pattern of weight change from pregnancy to 6 months postpartum: a latent growth model approach

OBJECTIVE

There is a lack of comprehensive understanding about patterns of weight change from pregnancy to childbirth and beyond. We describe the trajectory of weight change pattern from pre-pregnancy to 6 months postpartum and examine demographical and perinatal variables that predict the weight change using the latent growth model (LGM).

DESIGN AND SUBJECTS

This study used a longitudinal design. The study participants were 120 women whose body weights were measured at eight time points.

RESULTS

The adjusted mean pre-pregnancy weight was 52.57 kg. When the weight growth rate for 10-13 weeks of pregnancy and pre-pregnancy weight was set to 1, the body-weight change rate was 2.20 during the second trimester, 2.14 during the third trimester, -2.90 during the period from the third trimester to 2-3 weeks postpartum, -0.08 during the period from 2-3 weeks to 4-5 weeks postpartum, -0.37 during the period from 4-5 weeks to 11-12 weeks postpartum, and -0.65 during the period from 11-12 weeks to 24-25 weeks postpartum. On average, body weight increased 26.54% (13.95 kg) from pre-pregnancy to 36-39 weeks of pregnancy and body weight remained 6.26% (3.29 kg) higher at 24-25 weeks postpartum compare with pre-pregnancy. In terms of factors related to body weight, age was positively associated with pre-pregnancy body weight. Parity had a negative effect on the change of body weight. Women who had an increased change rate in body weight had higher newborn birth weights.

CONCLUSIONS

We found that weight change from pregnancy to postpartum followed a pattern that could be specified using the LGM approach. The women retained more than 6% of weight at 6 months postpartum compared with their pre-pregnancy weight.

Attitudes toward weight gain during pregnancy: results from the Norwegian mother and child cohort study (MoBa)

OBJECTIVE

To explore attitudes toward weight gain during pregnancy in women with and without eating disorders and across eating disorder subtypes, and to examine associations among weight-gain attitudes and actual gestational weight gain, infant birth weight, and infant size-for-gestational-age.

METHOD

Pregnant women (35,929) enrolled in the prospective population-based Norwegian mother and child cohort study (MoBa) provided information at approximately week 18 of gestation regarding eating disorders and weight gain attitudes. We explored these variables in women with anorexia nervosa, bulimia nervosa, eating disorder not otherwise specified, purging type, and binge eating disorder (BED).

RESULTS

The presence of an eating disorderly was associated with greater worry over gestational weight gain. In women without eating disorders, greater worry was associated with higher gestational weight gain, higher infant weights, greater likelihood of a large-for-gestational-age infant, and reduced likelihood of a small-for-gestational-age infant. Women with BED who reported greater worry also experienced higher weight gains during pregnancy.

DISCUSSION

Women with eating disorders tend to experience weight-gain-related worry during pregnancy. Early worry about gestational weight-gain may be a harbinger of high gestational gain.

Prenatal nutrition: a critical window of opportunity for mother and child

The prenatal period encompasses a critical window for future health and functioning of mother and child. Attention previously focused on undernutrition risk (i.e., in developing countries and famine conditions) shifted to mismatch between prenatal 'programming' by undernutrition and postnatal overconsumption (i.e., low birthweight vs rapid postnatal growth), now to overconsumption/overweight throughout the reproductive cycle and short- and long-term health risks, including obesity, diabetes, dyslipidemia and cardiovascular disease. Moreover, overconsumption/overweight do not guarantee adequacy of critical nutrients (i.e., against birth defects or for brain development). Multinutrient supplementation - including zinc, iodine, choline and long-chain polyunsaturated fatty acids, especially n-3 - may have advantages over single-nutrient supplements, for example, iron or folate. Future nutritional care for healthy in utero programming may necessitate individual assessment and follow-up, including preconception nutritional preparation, appropriate weight gain, metabolic balance and food-based regimens enhanced by key nutrient fortification and/or supplementation, warranting further research into nutritional optimization of pregnancy outcomes.