Abstract Context Contrary to nutritional guidelines, accumulating evidence shows that pregnant women’s energy intakes remain stable throughout trimesters. Although pregnant women may eat below their needs or underreport their energy intakes, it is also relevant to question how energy requirements – estimated through measurements of energy expenditure (EE) – change throughout pregnancy. Objective This review examined prospective studies that measured EE during pregnancy, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data sources PubMed/MEDLINE, Web of Science, Embase, and CINAHL databases were searched to identify relevant publications up to November 14, 2019. Study selection All studies that measured EE prospectively and objectively during pregnancy were included in this systematic review. Two authors independently screened 4852 references. A total of 32 studies were included in the final analysis. Data extraction One author extracted data and assessed the risk of bias and a second author did so for a random sample of studies (n = 7; 22%). Data analysis Increases in resting EE ranged from 0.5% to 18.3% (8–239 kcal), from 3.0% to 24.1% (45–327 kcal), and from 6.4% to 29.6% (93–416 kcal) between early and mid-, mid- and late, and early and late pregnancy, respectively. Increases in total EE ranged from 4.0% to 17.7% (84–363 kcal), from 0.2% to 30.2% (5–694 kcal), and from 7.9% to 33.2% (179–682 kcal) between early and mid-, mid- and late, and early and late pregnancy, respectively. Participants were mainly of normal weight, although many studies did not report important covariates such as prepregnancy body mass index and gestational weight gain adequacy. Conclusions Additional high-quality longitudinal studies (ie, with multiple objective measurements of EE in all periods of pregnancy while considering important confounding variables, like gestational weight gain) are required.
AbstractBackground:Insufficient and excessive gestational weight gain (GWG) have emerged as rising public health concerns affecting the majority of pregnant women in high-income countries, and are associated with a multitude of adverse maternal and infant health outcomes. The goal of this scoping review was to identify key structural vulnerability factors related to GWG and to examine the extent, range, and nature of research examining associations between those factors and GWG before the advent of the COVID-19 pandemic. Methods: Electronic searches were performed in October 2018, and updated in August 2019in the databases MEDLINE(R) ALL, EMBASE, PsycINFO, CINAHL, and Sociological Abstracts. Studies included needed to be set in high-income countries, have pregnant participants and an observational methodological design with inferential statistics performed between one or more structural vulnerability factors and GWG. Results: Of the 11,382 citations identified through database searches, 157 articles were included in the review. The structural vulnerability factors most commonly studied in association with GWG were race and ethnicity (n=91 articles), age (n=87), parity (n=48), education (n=44), income (n=39), marital status (n=28), immigration (n=19) and abuse (n=12). Moststudies were conducted in the USA (77%), a majority reported significant associations between these factors and GWG and 34% were specific to a population where all individuals were affected by one of more structural vulnerability factors. Race and ethnicity stood out as the most extensively studied factor; i.e., for the longest period (since 1976), with the highest number of published articles, the largest sample size (n=7,966,573) and the second highest (79%) proportion of studies reporting a significant relationship with GWG, with immigration status having the highest proportion (95%). Conclusions: To advance knowledge on the causes and consequences of excessive and insufficient GWG, research should extend beyond the USA and adopt an intersectional approach to unravel the complex interplay between social context, interacting structural vulnerability factors and specific measures of GWG. Such knowledge is required for the prevention of detrimental impacts on both maternal and offspring health.
The present study aimed to characterize dietary intake and diet quality from late pregnancy to six months postpartum. Participants (n = 28) completed 2–3 Web-based 24 h recalls at three distinct periods: (1) during the third trimester of pregnancy; (2) three months and (3) six months after delivery. Energy, macro-and micronutrient intakes (from foods and supplements), as well as the Canadian healthy eating index (C-HEI) were derived from the dietary recalls. No significant variation in energy and macronutrient intakes was observed between time points. The proportion of women taking at least one supplement decreased over time (p = 0.003). The total intake of several micronutrients (vitamins A, C, D, group B vitamins, iron, magnesium, zinc, calcium, phosphorus, manganese, and copper) decreased significantly over time (p < 0.05 for all micronutrients). The total C-HEI score and its components did not change, except for the total vegetables and fruit subscore, which decreased over time (8.2 ± 2.0 in the 3rd trimester, 7.1 ± 2.2 at three months postpartum, 6.9 ± 2.4 at 6 months postpartum, p = 0.04). In conclusion, we observed a general stability in diet quality, energy, and macronutrient intakes from the third trimester of pregnancy to six months postpartum. However, several micronutrient intakes decreased over time, mostly due to changes in supplement use.
Genetic polymorphisms of glutathione S ‐transferases (GSTs) have been shown to affect fasting serum ascorbic acid (vitamin C) concentrations. The objective of this study was to determine whether three common polymorphisms in the GSTM1, GSTT1 and GSTP1 genes modify the serum ascorbic acid response to dietary vitamin C. Non‐smoking men and women (n= 1016) aged 20‐29 completed a 196‐item food frequency questionnaire that was used to estimate vitamin C intake, and provided a fasting blood sample for genotyping and determining serum ascorbic acid concentrations by HPLC. A significant diet‐gene interaction was observed for the GSTT1 polymorphism (p = 0.04). After adjusting for caloric intake, sex, ethnicity, season, c‐reactive protein and BMI, the Spearman correlation between dietary vitamin C and serum ascorbic acid was 0.36 (p<0.0001) for the GSTT1*0/*0 genotype and 0.14 (p=0.01) for the GSTT1*1/*1 + *1/*0 genotypes). Average serum ascorbic acid concentrations (mean ± SE) were higher among individuals with the GSTT1*1/*1 + *1/*0 than those with the GSTT1*0/*0 genotype (28.8 ± 1.1 versus 25.4 ± 1.5μmol/L) (p= 0.04, adjusted for caloric intake, sex, race, season, c‐reactive protein and BMI). No significant diet‐gene interactions were observed for GSTM1 (p=0.59) or GSTP1 (p=0.72). Our findings suggest that GSTT1 genotypes modify the serum ascorbic acid response to vitamin C intake. Grant Funding Source Advanced Foods & Materials Network
Canadian expert guidelines recommend low-risk women to consume a daily multivitamin supplement containing 400 µg of folic acid (FA) to prevent neural tube defects. Mandatory food fortification coupled with intake of prenatal vitamin/mineral supplements (PVS), most of which contain ≥ 1000 µg-FA, has resulted in an unprecedented shift in Canadian pregnant women folate status. This study assessed the knowledge, attitude and practice (KAP) of physicians regarding periconceptional FA recommendations, intake and health related outcomes, since they play an essential role in promoting appropriate FA intake. Seventy-seven physicians answered the self-administered KAP survey. Only half of physicians knew the correct dose and duration of FA for low-risk women. Approximately 70% were unsure of, or unfamiliar with the most recent guidelines and 60% of physicians most often recommend a ≥ 1000 µg-FA supplement. Knowledge score 1 (KS1), which related to low-risk women, was associated with physicians' attitude toward believing that most PVS contain the recommended amount of FA (p = 0.004). Significant correlations were also found between KS1 and the total practice score (TPS) (r = 0.45,
AbstractBackground: Inadequate and excessive gestational weight gain (GWG) are rising epidemiological health concerns, affecting a substantial proportion of pregnant women in high-income countries and contributing to a multitude of adverse maternal and infant health outcomes. The aim of this scoping review was to identify key structural vulnerability factors (SVFs) related to GWG, and to examine the extent, range, and nature of the existing literature to inform future research. Methods: Electronic searches were performed in October 2018 (updated in August 2019)in MEDLINE(R) ALL, EMBASE, PsycINFO, CINAHL, and Sociological Abstracts databases. Eligible studies had an observational design, had to be conducted before COVID-19, in a high-income country, have pregnant participants, and perform inferential statistics between an SVF and GWG. Results: Of the 157 included articles, the eight SVFs most commonly studied in association with GWG were race/ethnicity (n=91 articles), age (n=87), parity (n=48), education (n=44), income (n=39), marital status (n=28), immigration (n=19), and abuse (n=12). Substantialheterogeneity across study contexts, methodologies, populations, and findings was identified. Studies spanned 22 high-income countries, were predominantly conducted in the USA (77%), and most studies (60%) had a retrospective design. Race/ethnicity was the most extensively studied factor, covering the longest time period (since 1976) and having the largest sample size, and the second-highest proportion of studies reporting a significant relationship with GWG (79%), following immigration status (95%). Conclusions: Given the heterogeneity in findings across studies, adopting an intersectional approach may enhance our understanding of the complex interplay between SVFs and the social context in relation to GWG. This nuanced perspective is critical for informing future research and developing effective strategies to address the pervasive perinatal health challenges associated with inadequate and excessive GWG.
