Institute Of Medicine Guidelines Research Articles

Optimal gestational weight gain associated with improved perinatal outcomes in women with gestational diabetes mellitus: a population-based study in the United States

BackgroundOptimal gestational weight change (GWC) is little known among pregnant women with gestational diabetes mellitus (GDM). ObjectiveThis study aimed to explore the optimal GWC ranges for women with GDM and validate these ranges compared to the Institute of Medicine (IOM) guidelines. MethodsA population-based cohort study using natality data from the National Center for Health Statistics (NCHS) in the United States included 1,338,460 mother-infant pairs with GDM from 2014 to 2020. Poisson regression models were performed to identify GWC ranges (GDM targets) associated with acceptable risks (< 10% increase) for a severity-weighted composite outcome including preterm birth (PTB) < 37 weeks, large for gestational age (LGA, birthweight > 90th percentile) and small for gestational age (SGA, birthweight < 10th percentile). These targets were validated in individual outcomes including PTB, LGA, SGA, hypertensive disorders of pregnancy, neonatal intensive care unit admission and neonatal respiratory morbidity and compared with the IOM guidelines using logistic regression models with population-attributable fractions (PAFs) calculated. ResultsThe severity-weighted composite outcome had a U-shaped or a J-shaped relationship with GWC across body mass index (BMI) categories. The GDM targets were 14.1-20.3 kg, 9.0-17.0 kg, 4.8-13.8 kg, -0.8-10.8 kg, -2.4-8.2 kg, and -8.3-6.0 kg for underweight, normal weight, overweight, class 1 obesity, class 2 obesity, and class 3 obesity, respectively. GWC outside the GDM or the IOM targets was associated with increased adverse perinatal outcomes in validation analyses. PAFs indicated that the IOM guidelines reduced a similar or higher proportion of adverse perinatal outcomes compared to the GDM targets for women with GDM, with the exception of those with class 2 and 3 obesity. ConclusionsThe IOM guidelines are generally applicable for women with GDM, with the exception of women with moderate and severe obesity. The optimal GWC ranges for women with GDM and moderate to severe obesity may be lower than the IOM guidelines.

Complicaciones del embarazo en pacientes con ganancia excesiva de peso gestacional en un hospital público peruano

Objective: TTo determine the demographic and clinical characteristics, of pregnant women with excessive gestational weight gain. And determine their relationship with maternal complications. Methods: Analytical, retrospective study. Full-term pregnant women, older than 18 years and with single live fetuses, with legible clinical history and prenatal care card with first and last check-up, treated at a public hospital in Peru between January - June 2022, were included. Patients with mental problems and those with fetuses with malformations, were excluded. The variables measured were: sociodemographic characteristics, obstetric, gestational weight gain, and maternal complications. Excess gestational weight was defined using pre-pregnancy body mass index, difference in weight between the first and last prenatal check-up, and Institute of Medicine guidelines. A descriptive analysis was made and to recognize the relationship between excessive gestational weight and maternal results, the X2 test was used. The National University of San Agustín Institutional Research Ethics Committee granted approval of the study. Results: We included 1021 pregnant women in the study. Of these, 49.0% had excessive gestational weight. 43.0% of overweight patients had maternal complications. A relationship was found between excessive weight gain in pregnancy and gestational diabetes. Conclusions: Patients with excessive weight gain in pregnancy were more likely to have gestational diabetes. Keywords: Body mass index, Gestational weight gain, Pregnancy complications, Gestational diabetes, Peru.

Combined effects of pre-pregnancy BMI and gestational weight gain on preterm birth: comparison between spontaneous and ART conception.

Inappropriate pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) are both linked to preterm birth (PTB); however, which one plays a dominant role in PTB risk is not yet sure. We aimed to evaluate the combined effect of pre-pregnancy BMI and GWG on the risk of PTB in singleton pregnancies conceived both spontaneously and through assisted reproductive technology (ART). The data included all mothers (n = 17,540,977) who had a live singleton birth from the US National Vital Statistics System (NVSS) 2015-2019. Logistic regression models, quantile-g-computation, and generalized additive model were used to analyze the combined association of pre-pregnancy BMI and GWG with PTB. The singleton PTB rate was significantly higher in ART pregnancies (11.5%) than in non-ART pregnancies (7.9%). When compared to those women with pre-pregnancy normal weight and GWG within Institute of Medicine (IOM) guidelines, the highest PTB risk was observed in non-ART women with pre-pregnancy underweight and GWG below IOM guidelines (aOR 2.56; 95% CI 2.53-2.60) and in ART women with pre-pregnancy obese and GWG below IOM guidelines (aOR 2.56; 95%CI 2.36-2.78). GWG dominated the combined effect with its joint effect coefficient of - 0.281 (P < 0.05) in non-ART women and - 0.108 (P < 0.05) in ART women. Inappropriate GWG played a dominant role in increasing the risk of PTB in both non-ART and ART populations. Counseling regarding pre-pregnancy BMI and especially GWG appears to be even more crucial for pregnancies conceived via ART, given their impact on PTB.

Digital Self-Monitoring Tools for the Management of Gestational Weight Gain: Protocol for a Systematic Review.

Gestational weight gain (GWG) exceeding the recommendations of the Institute of Medicine (in the United States) is associated with numerous adverse maternal and infant health outcomes. While many behavioral interventions targeting nutrition and physical activity have been developed to promote GWG within the Institute of Medicine guidelines, engagement and results are variable. Technology-mediated interventions can potentially increase the feasibility, acceptability, and reach of interventions, particularly for pregnant women, for whom integration of interventions into daily life may be critical to retention and adherence. Previous reviews highlight GWG self-monitoring as a common intervention component, and emerging work has begun to integrate digital self-monitoring into technology-mediated interventions. With rapid advances in technology-mediated interventions, a focused synthesis of literature examining the role of digital self-monitoring tools in managing GWG is warranted to guide clinical practice and inform future studies. The proposed review aims to synthesize the emerging research base evaluating digital GWG self-monitoring interventions, primarily focusing on whether the intervention is effective in managing GWG. Depending on the characteristics of the included research, secondary focus areas will comprise intervention recruitment and retention, feasibility, acceptability, and differences between stand-alone and multicomponent interventions. This protocol was developed following the PRISMA-P (Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols) guidelines for systematic review protocols. The proposed review would use a planned and systematic approach to identify, evaluate, and synthesize relevant and recent empirical quantitative studies (reported in English) examining the use of digital weight self-monitoring tools in the context of technology-mediated interventions to manage GWG in pregnant US adults, with at least 2 instances of data collection. Literature eligible for inclusion will have a publication date between January 2010 and July 2020. The Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies will be used to assess the methodological quality of included studies across various domains, and results will be synthesized and summarized per the synthesis without meta-analysis guidelines. The initial queries of 1150 records have been executed and papers have been screened for inclusion. Data extractions are expected to be finished by December 2023. Results are expected in 2024. The systematic review that will be generated from this protocol will offer evidence for the use of digital self-monitoring tools in the management of GWG. The planned, focused synthesis of relevant literature has the potential to inform the use of digital weight self-monitoring tools in the context of future technology-mediated interventions to manage GWG. In addition, the planned review has the potential to contribute as part of a broader movement in research toward empirically supporting the inclusion of specific components within more extensive, multicomponent interventions to balance parsimony and effectiveness. PROSPERO CRD42020204820; https://tinyurl.com/ybzt6bvr. PRR1-10.2196/50145.

High pre-pregnancy body mass index and gestational weight gain among women belonging to upper SES from Delhi, India

Background and objectiveWith increase in prevalence of obesity and an increasing trend in the birth of macrosomic infants, Institute of Medicine (IOM) guidelines pertaining to optimal gestational weight gain (GWG) required for positive pregnancy outcome were revised in 1990 and 2009. Since, in the Indian scenario, no recommendations exist for optimum GWG for obese (OB) and overweight (OW) women, we assessed the pattern of GWG w.r.t Institute of Medicine (IOM), 2009 among the subjects with different body mass index (BMI). Study designPresent data were a part of a longitudinal observational study wherein, 312 pregnant women (≤12th week of gestation) attending private antenatal clinics were followed till term and their weight was monitored regularly at pre-determined intervals i.e., 12th–14th, 18th–20th, 24th–26th, 30th–32nd, 36th + week of gestation and compared w.r.t IOM guidelines 2009. Results66.37 %, 57.89 % and 11.69 % of OB, OW and normal weight (NW) subjects respectively had weight gain exceeding their GWG limits. About 5 %,10.53 %, 33.77 % of OB, OW and NW subjects respectively had gained weight less than GWG limits (p = 0.000***). ConclusionAn increase in GWG inadequacy with increase in BMI and pronounced variations in GWG among OB and OW subjects underscore the necessity to monitor GWG especially among the subjects with high BMI.

Risk factors for inadequate and excessive gestational weight gain in 25 low- and middle-income countries: An individual-level participant meta-analysis.

Many women experience suboptimal gestational weight gain (GWG) in low- and middle-income countries (LMICs), but our understanding of risk factors associated with GWG in these settings is limited. We investigated the relationships between demographic, anthropometric, lifestyle, and clinical factors and GWG in prospectively collected data from LMICs. We conducted an individual participant-level meta-analysis of risk factors for GWG outcomes among 138,286 pregnant women with singleton pregnancies in 55 studies (27 randomized controlled trials and 28 prospective cohorts from 25 LMICs). Data sources were identified through PubMed, Embase, and Web of Science searches for articles published from January 2000 to March 2019. Titles and abstracts of articles identified in all databases were independently screened by 2 team members according to the following eligibility criteria: following inclusion criteria: (1) GWG data collection took place in an LMIC; (2) the study was a prospective cohort or randomized trial; (3) study participants were pregnant; and (4) the study was not conducted exclusively among human immunodeficiency virus (HIV)-infected women or women with other health conditions that could limit the generalizability of the results. The Institute of Medicine (IOM) body mass index (BMI)-specific guidelines were used to determine the adequacy of GWG, which we calculated as the ratio of the total observed weight gain over the mean recommended weight gain. Study outcomes included severely inadequate GWG (percent adequacy of GWG <70), inadequate GWG (percent adequacy of GWG <90, inclusive of severely inadequate), and excessive GWG (percent adequacy of GWG >125). Multivariable estimates from each study were pooled using fixed-effects meta-analysis. Study-specific regression models for each risk factor included all other demographic risk factors measured in a particular study as potential confounders, as well as BMI, maternal height, pre-pregnancy smoking, and chronic hypertension. Risk factors occurring during pregnancy were further adjusted for receipt of study intervention (if any) and 3-month calendar period. The INTERGROWTH-21st standard was used to define high and low GWG among normal weight women in a sensitivity analysis. The prevalence of inadequate GWG was 54%, while the prevalence of excessive weight gain was 22%. In multivariable models, factors that were associated with a higher risk of inadequate GWG included short maternal stature (<145 cm), tobacco smoking, and HIV infection. A mid-upper arm circumference (MUAC) of ≥28.1 cm was associated with the largest increase in risk for excessive GWG (risk ratio (RR) 3.02, 95% confidence interval (CI) [2.86, 3.19]). The estimated pooled difference in absolute risk between those with MUAC of ≥28.1 cm compared to those with a MUAC of 24 to 28.09 cm was 5.8% (95% CI 3.1% to 8.4%). Higher levels of education and age <20 years were also associated with an increased risk of excessive GWG. Results using the INTERGROWTH-21st standard among normal weight women were similar but attenuated compared to the results using the IOM guidelines among normal weight women. Limitations of the study's methodology include differences in the availability of risk factors and potential confounders measured in each individual dataset; not all risk factors or potential confounders of interest were available across datasets and data on potential confounders collected across studies. Inadequate GWG is a significant public health concern in LMICs. We identified diverse nutritional, behavioral, and clinical risk factors for inadequate GWG, highlighting the need for integrated approaches to optimizing GWG in LMICs. The prevalence of excessive GWG suggests that attention to the emerging burden of excessive GWG in LMICs is also warranted.

Maternal and neonatal outcomes in women with twin pregnancies based on gestational weight gain: An updated systematic review and meta-analysis.

This updated systematic review and meta-analysis aimed to assess maternal and fetal outcomes of pregnancies based on the Institute of Medicine (IOM) guidelines of gestational weight gain (GWG). PubMED, SCOPUS, EMBASE and Web of Science were searched up to 30th July 2022. All studies evaluating maternal and/or neonatal outcomes of twin pregnancies based on the IOM guidelines of gestational weight gain were included. Twenty two studies were included. Mothers with twin pregnancies experiencing inadequate GWG showed higher incidence of gestational diabetes with the risk ratio (RR) 1.22 95% CI (0.95,1.57), p=0.0005, i2= 69% and premature rupture of membrane (PROM) with RR 1.14 95% CI (0.99, 1.30), p=0.07; i2=0% that coincided with higher rates of preterm birth, low birth weight, small for gestational age (SGA) and admission to NICU in neonates. Mothers with excessive GWG had higher risk of developing gestational hypertension with RR 1.59 95% CI (1.22, 2.07), p=0.0006, i2=75% and extremely preterm delivery (<32 weeks). Within the limitations of this review, GWG was found to be a predictable risk factor for adverse maternal and neonatal outcomes of twin pregnancies.

Evaluating the application of the 2009 Institute of Medicine gestational weight gain guidelines on pregnant Chinese women

ABSTRACT Background The 2009 Institute of Medicine (IOM) gestational weight gain (GWG) guidelines were initially developed for pregnant women in the United States. Objective This study aimed to investigate whether the IOM guidelines were suitable for pregnant Chinese women. Methods A retrospective cohort study comprising 20,593 singleton pregnant women was conducted at the Beijing Obstetrics and Gynaecology Hospital (1 January 2018 to 31 December 2019). Applicability was evaluated by comparing the GWG corresponding to the lowest point of the predicted composite risk curve with the 2009 IOM GWG Guidelines. The IOM Guidelines serve as the standard for the GWG categories and the pre-pregnancy body mass index. An exponential function model was used to fit the weight gain during pregnancy and the probability of caesarean section, preterm birth, small for gestational age, and large for gestational age. A quadratic function model was used to fit the combined probability of the above-mentioned adverse pregnancy outcomes. The applicability of the IOM guidelines was evaluated by comparing the weights corresponding to the lowest predicted probability with the GWG range recommended by the IOM guidelines. Results According to the 2009 IOM GWG Guidelines, 43% of the women achieved adequate weight, almost 32% gained excessive weight, and 25% gained inadequate weight. The GWG range proposed by the IOM included the lowest predicted probability value for underweight women and exceeded the lowest predicted probability for normal weight, overweight, and obese women. Conclusions The 2009 IOM guidelines were suitable for Chinese women whose pre-pregnancy body mass index was classified as underweight. The guidelines were not suitable for normal, overweight, or obese pre-pregnancy body mass index classifications. Therefore, based on the above evidence, the 2009 IOM guidelines are not suitable for all Chinese women.

Comparison of the 2009 Institute of Medicine and 2021 Chinese guidelines for gestational weight gain: A retrospective population-based cohort study.

To analyze the associations between gestational weight gain (GWG) and perinatal outcomes based on the GWG guidelines of the Chinese Nutrition Society (CNS) and the Institute of Medicine (IOM). This was a retrospective study with 9075 low-risk singleton pregnant women. Logistic regression model was used to analyze associations between GWG categories and perinatal outcomes. Sensitivity analyses were performed based on pre-pregnancy body mass index (calculated as weight in kilograms divided by the square of height in meters). Excessive GWG as defined by the two guidelines was associated with a higher risk of adverse perinatal outcomes. Inadequate GWG was associated with higher risks of small for gestational age (adjusted odds ratio [aOR] 1.34, 95% confidence interval [CI] 1.10-1.64) and preterm birth (aOR 1.70, 95% CI 1.22-2.36), but a lower risk of large for gestational age (LGA) (aOR 0.77, 95% CI 0.63-0.95) according to the IOM guidelines. When using the CNS guidelines, inadequate GWG was associated with only a lower risk of preterm birth (aOR 1.80, 95% CI 1.19-2.70). Sensitivity analyses suggested that excessive GWG was associated with a higher risk of LGA in underweight women. Both guidelines could demonstrate the relationship between GWG and adverse perinatal outcomes. The CNS guidelines were more suitable for the Chinese population with underweight or normal weight before pregnancy, whereas IOM was more suitable for pregnant women with inadequate GWG.

Effect of Circadian Distribution of Energy and Macronutrients on Gestational Weight Gain in Chinese Pregnant Women.

Gestational weight gain (GWG) may be affected by the timing of dietary intake. Previous studies have reported contradictory findings, possibly due to inconsistent characterizations of meal timing. We conducted a birth cohort study in Tianjin to determine the effect of daily energy and macronutrient distribution in mid and late pregnancy on GWG. Dietary intake information in the second and third trimesters used three 24-h dietary recalls, and meal timing was defined in relation to sleep/wake timing. The adequacy of GWG was assessed using recommendations from the Institute of Medicine guidelines. Pregnant women who had a relatively high average energy and macronutrient distribution in the late afternoon-early evening time window exhibited a greater GWG rate and a greater total GWG than that in morning time window during the third trimester (β = 0.707; β = 0.316). Carbohydrate intake in the morning of the second and third trimesters (β = 0.005; β = 0.008) was positively associated with GWG rates. Morning carbohydrate intake in the second trimester was also positively associated with total GWG (β = 0.004). Fat intake in the morning of the third trimester (β = 0.051; β = 0.020) was positively associated with the GWG rates and total GWG. Excessive GWG of Chinese pregnant women was related closely to eating behavior focused on the late afternoon-early evening and carbohydrate and fat intake in the morning during the second and third trimesters.

Conflicts of Interest Among Infectious Diseases Clinical Practice Guideline Authors and the Pharmaceutical Industry

This cross-sectional study assesses the prevalence of conflicts of interest (COI) associated with guideline-recommended drugs among Infectious Diseases Society of America clinical practice guideline authors and compliance with the Council on Medical Specialty Societies and Institute of Medicine guidelines.

Binge-spectrum symptoms in their association with higher gestational weight gain.

Gestational weight gain (GWG) above or below recommendations is common and has implications for parent and infant health. Bulimia nervosa and binge-eating disorder during pregnancy have been associated with higher GWG. Yet, little research has examined the associations between binge-spectrum symptoms and GWG. Likewise, few interventions exist to adequately prevent GWG. The current study investigated a broad range of predictors of GWG, with the goal of identifying potentially modifiable risk factors. We conducted secondary data analyses of a subsample of individuals from the Alberta Pregnancy Outcome and Nutrition (APrON) longitudinal cohort study. Multinomial logistic regression estimated the odds of gestational weight gain (GWG) outside of Institute of Medicine (IOM) recommendations and linear regression was used to examine total GWG continuously. Of the 1644 participants included, 848 (51.6%) exceeded the IOM's guidelines for GWG, and 272 (16.5%) gained below these recommendations. Binge-spectrum symptom symptomatology during pregnancy was not associated with exceeding GWG recommendations after accounting for post-secondary education, identifying as European Canadian, and higher pre-pregnancy body mass index (BMI). However, greater self-reported binge-spectrum symptomatology during pregnancy was associated with higher total GWG after accounting for age, parity, and pre-pregnancy BMI. In addition to replicating identified predictors of higher GWG, we found that greater binge-spectrum symptomatology was associated with higher total GWG. These findings suggest that routine screening for eating pathology during pregnancy may identify those at risk for excess GWG. Gestational weight gain (GWG) outside of recommended ranges is associated with adverse outcomes. Little work has examined the associations between eating disorder symptoms and GWG. This study found that bulimia and binge-eating symptoms were uniquely associated with higher GWG beyond known risk factors. These findings support routine screening of eating disorder symptoms and interventions to help individuals gain within GWG recommendations during pregnancy.

Rates of maternal weight gain over the course of pregnancy and offspring risk of neurodevelopmental disorders

BackgroundPrevious studies have suggested that gestational weight gain (GWG) outside an optimal range increases the risks of neurodevelopmental disorders (NDDs) in offspring including autism spectrum disorder (ASD), intellectual disability (ID), and attention deficit/hyperactivity disorder (ADHD). The sequential development of the fetal brain suggests that its vulnerability may vary depending on the timing of exposure. Therefore, we aimed to investigate the associations of not only gestational age-standardized total GWG (GWG z-scores) but also the rate of GWG (RGWG) in the second and third trimesters with risks of NDDs in offspring.MethodsIn this population-based cohort study, we used maternal weight data from antenatal care records collected for 57,822 children born to 53,516 mothers between 2007 and 2010 in the Stockholm Youth Cohort. Children were followed from 2 years of age to December 31, 2016. GWG z-scores and RGWG (kg/week) in the second and third trimesters were considered as continuous variables in cox regression models, clustered on maternal identification numbers. Nonlinear relationships were accommodated using restricted cubic splines with 3 knots. RGWG were also categorized according to the 2009 US Institute of Medicine (IOM) guidelines for optimal GWG. According to the IOM guidelines, the optimal rate of GWG for the second and third trimesters for underweight, normal weight, overweight, and obese categories were 0.44–0.58, 0.35–0.50, 0.23–0.33, and 0.17–0.27 kg/week, respectively.ResultsDuring a mean follow-up of 5.4 years (until children were on average 7.4 years old), 2205 (3.8%) children were diagnosed with NDDs, of which 1119 (1.9%) received a diagnosis of ASD, 1353 (2.3%) ADHD, and 270 (0.5%) ID. We observed a J-shaped association between total GWG z-score and offspring risk of NDDs, with higher total GWG (GWG z-score = 2) associated with 19% increased risk of any NDD (95% CI = 3–37%) and lower total GWG (GWG z-score = − 2) associated with 12% increased risk of any NDDs (95% CI = 2–23%), compared to the reference (GWG z-score = 0). In the second trimester, lower RGWG (0.25 kg/week) was associated with a 9% increased risk of any NDD diagnosis (95% CI = 4–15%) compared to the median of 0.57 kg/week, with no apparent relationship between higher RGWG and risk of NDDs. In the third trimester, there was no apparent association between lower RGWG and risk of NDDs, though higher RGWG (1 kg/week) was associated with a 28% increased risk of NDD diagnosis (95% CI = 16–40%), compared to the median (0.51 kg/week). When considering categorized RGWG, we found that slow weight gain in the second trimester followed by rapid weight gain in the third trimester most significantly increased the risk of ADHD (HRadjusted = 1.55, 1.13–2.13) and ID (HRadjusted = 2.53, 1.15–5.55) in offspring. The main limitations of our study are the relatively few years for which detailed GWG data were available and the relatively short follow-up for the outcomes, limiting power to detect associations and misclassifying children who receive an NDD diagnosis later in childhood.ConclusionsThe relationship between maternal weight gain and children’s risk of NDDs varied according to timing in pregnancy, with the greatest risks associated with slow weight gain in the second trimester and rapid weight gain in the third trimester.

Dietary Quality Indices in Early Pregnancy and Rate of Gestational Weight Gain among a Prospective Multi-Racial and Ethnic Cohort.

Meeting the Institute of Medicine (IOM) gestational weight gain (GWG) guidelines is associated with a reduced risk of adverse perinatal outcomes. Overall diet quality comprehensively assesses dietary components and accounts for interactions between them. While GWG is influenced by maternal diet, its association with overall diet quality-measured by various dietary quality indices-is not well-defined. We prospectively estimated the relationship between four established dietary quality indices and the risk of GWG rate above (excessive) or below (inadequate) IOM guidelines in a multi-racial and ethnic cohort of 2914 pregnant people from the Pregnancy Environment and Lifestyle Study (2014-2019). We assessed diet quality using the Healthy Eating Index 2010 (HEI-2010), alternate Mediterranean Diet (aMED), Dietary Approaches to Stop Hypertension (DASH), and Empirical Dietary Inflammatory Index (EDIP). Following the first trimester, 56% of the cohort had excessive GWG, and 14% had inadequate GWG. Poor diet quality (below the 75th percentile), measured by HEI-2010, was associated with a higher risk of excessive GWG in the second and third trimesters [RR = 1.03 (1.00, 1.06)]. Effect modification of this relationship by race and ethnicity and pre-pregnancy BMI was assessed. We found poor diet quality to be associated with elevated risk of excessive GWG among Black participants [RR = 1.14 (1.02, 1.28)] and White participants [RR 1.07 (1.01, 1.12)]. This was also the case for participants with pre-pregnancy BMI < 25.0 [RR 1.05 (1.00, 1.10)]. These results suggest that diet quality measured by the HEI-2010 is associated with excessive GWG, and the associations appear to be stronger among pregnant people without overweight or obesity and pregnant people who identify as Black or White race and ethnicity.

Associations between gestational weight gain and adverse neonatal outcomes: a comparison between the US and the Chinese guidelines in Chinese women with twin pregnancies

BackgroundAppropriate gestational weight gain (GWG) is essential for maternal and fetal health. For twin pregnancies among Caucasian women, the Institute of Medicine (IOM) guidelines can be used to monitor and guide GWG. We aimed to externally validate and compare the IOM guidelines and the recently released guidelines for Chinese women with twin pregnancies regarding the applicability of their recommendations on total GWG (TGWG).MethodA retrospective cohort study of 1534 women who were aged 18–45 years and gave birth to twins at ≥ 26 gestational weeks between October 2016 and June 2020 was conducted in Guangzhou, China. Women's TGWG was categorized into inadequate, optimal, and excess per the IOM and the Chinese guidelines. Multivariable generalized estimating equations logistic regression was used to estimate the risk associations between TGWG categories and adverse neonatal outcomes. Cohen’s Kappa coefficient was calculated to evaluate the agreement between the IOM and the Chinese guidelines.ResultsDefined by either the IOM or the Chinese guidelines, women with inadequate TGWG, compared with those with optimal TGWG, demonstrated higher risks of small-for-gestational-age birth and neonatal jaundice, while women with excess TGWG had a higher risk of delivering large-for-gestational-age infants. The agreement between the two guidelines was relatively high (Kappa coefficient = 0.721). Compared with those in the optimal TGWG group by both sets of the guidelines, women classified into the optimal group by the Chinese guidelines but into the inadequate group by the IOM guidelines (n = 214) demonstrated a statistically non-significant increase in the risk of all the adverse neonatal outcomes combined.ConclusionsThe IOM and the Chinese guidelines are both applicable to Chinese women with twin pregnancies.

Gestational Weight Gain and Small for Gestational Age in Obese Women: A Systematic Review and Meta-Analysis.

This systematic review and meta-analysis evaluates the relationship between gestational weight gain and the risk of small for gestational age in obese pregnant women. Studies were identified by searching the Web of Science, Embase, and PubMed databases up to June 30th, 2022. The meta-analysis was carried out to determine the risk of small for gestational age with gestational weight gain (GWG) below the 2009 Institute of Medicine (IOM) guidelines compared with within the guidelines in obese women. The Newcastle-Ottawa Scale was used to assess the methodological quality. The chi-squared test, Q test, and I2 test were used to evaluate statistical heterogeneity. Subgroup analyses were conducted, and publication bias was assessed by funnel plots and Egger's test. Sensitivity analyses were performed for three groups of obese people (I: BMI 30-34.9 kg/m2, II: BMI 35-39.9 kg/m2, and III: BMI ≥ 40 kg/m2) to examine the association of obesity and SGA. A total of 788 references were screened, and 29 studies (n = 1242420 obese women) were included in the systematic review. Obese women who gained weight below the IOM guideline had a higher risk of SGA than those who gained weight within the guideline (OR = 1.27, 95% CI = 1.16-1.38, Z = 5.36). Both weight loss (<0 kg) and inadequate weight (0-4.9 kg) during pregnancy in obese women are associated with an increased risk of SGA (OR = 1.50, 95% CI = 1.37-1.64, Z = 8.82) (OR = 1.18, 95% CI = 1.14-1.23, Z = 8.06). The same conclusions were also confirmed for the three obesity classes (I: OR = 1.38, 95% CI = 1.29-1.47; II: OR = 1.39, 95% CI = 1.30-1.49; and III: OR = 1.26, 95% CI = 1.16-1.37). Subgroup analysis by country showed that GWG below guidelines in obese women of the USA and Europe was associated with risk for SGA (USA (OR = 1.30, 95% CI = 1.15-1.46), Europe (OR = 1.24, 95% CI = 1.11-1.40)) and not in Asia (OR = 1.17, 95% CI = 0.91-1.50). Our findings indicated that obese pregnant women who had weight loss or inadequate weight (0-4.9 kg) according to the IOM guideline had increased risks for SGA. Moreover, we also evaluated that gestational weight loss (<0 kg) in these pregnancies was associated with an increased risk for SGA compared with inadequate weight (0-4.9 kg) in these pregnancies. Therefore, the clinical focus should assist obese women to achieve GWG within the IOM guidelines to decrease the risk for SGA.

Circulating vitamin D and breast cancer risk: an international pooling project of 17 cohorts.

Laboratory and animal research support a protective role for vitamin D in breast carcinogenesis, but epidemiologic studies have been inconclusive. To examine comprehensively the relationship of circulating 25-hydroxyvitamin D [25(OH)D] to subsequent breast cancer incidence, we harmonized and pooled participant-level data from 10 U.S. and 7 European prospective cohorts. Included were 10,484 invasive breast cancer cases and 12,953 matched controls. Median age (interdecile range) was 57 (42-68) years at blood collection and 63 (49-75) years at breast cancer diagnosis. Prediagnostic circulating 25(OH)D was either newly measured using a widely accepted immunoassay and laboratory or, if previously measured by the cohort, calibrated to this assay to permit using a common metric. Study-specific relative risks (RRs) for season-standardized 25(OH)D concentrations were estimated by conditional logistic regression and combined by random-effects models. Circulating 25(OH)D increased from a median of 22.6nmol/L in consortium-wide decile 1to93.2nmol/L in decile 10. Breast cancer risk in each decile was not statistically significantly different from risk in decile 5 in models adjusted for breast cancer risk factors, and no trend was apparent (P-trend = 0.64). Compared to women with sufficient 25(OH)D based on Institute of Medicine guidelines (50- < 62.5nmol/L), RRs were not statistically significantly different at either low concentrations (< 20nmol/L, 3% of controls) or high concentrations (100- < 125nmol/L, 3%of controls; ≥ 125nmol/L, 0.7%of controls). RR per 25nmol/L increase in 25(OH)D was 0.99 [95% confidence intervaI (CI) 0.95-1.03]. Associations remained null across subgroups, including those defined by body mass index, physical activity, latitude, and season of blood collection. Although none of the associations by tumor characteristics reached statistical significance, suggestive inverse associations were seen for distant and triple negative tumors. Circulating 25(OH)D, comparably measured in 17 international cohorts and season-standardized, was not related to subsequent incidence of invasive breast cancer over a broad range in vitamin D status.

Correlation between maternal weight gain and birth weight among term babies

Introduction: Healthy and well-nourished mother is likely to give birth to a healthy normal child with adequate birth weight. We aimed to determine the correlation of gestational weight gain and newborn’s birth weight. Methods: We studied participant-level data for 295 pregnant women coming for delivery services between January 2018 and December 2020 at Shree Birendra Hospital, Chhauni, Kathmandu, Nepal. A retrospective data of pre-pregnancy body mass index, maternal weight gain during different trimesters of pregnancy were collected. The prevalence of small and large for gestational babies were compared with mother’s weight gain according to Institute of Medicine (IOM) guidelines. Pearson test was used to assess the correlation between gross maternal weight gain during pregnancy and birth weight. Results: Among 295 women, 12.2% underweight, 55.6% normal weight, 26.1% overweight and 6.1% were obese. The overall mean gestational weight gain (GWG) was 11.78 kg. Birth weight of the babies ranged from 1500 gm to 5100 gm with mean weight of 3148 gm. Majority of small for gestational age and large for gestational babies were seen among women below and above IOM guidelines respectively. Conclusions: Findings from this study suggest that maternal weight gain during pregnancy increases the birth weight. Across all BMI categories, insufficient GWG is associated with slightly increased risk of SGA, while relative risk of LGA is higher in excess GWG group.

Gestational weight gain influences neonatal outcomes in women with obesity and gestational diabetes

IntroductionObesity and gestational diabetes mellitus (GDM) are associated with an increased risk of perinatal complications and obesity in the offspring. However, the impact of gestational weight gain (GWG) on maternal and foetal outcomes is controversial. Patients and methodsRetrospective study of 220 women with GDM and pre-pregnancy body mass index (BMI)>30kg/m2. Pregnant women were classified according to the Institute of Medicine (IOM) recommendations regarding their prior BMI and GWG. We evaluated the impact of GWG on perinatal and obstetric outcomes. ResultsMean maternal age was 34.7±5.3 years. Pre-pregnancy obesity was classified as class I in 55.3% of the cases, class II in 32.0% and class III in 12.7%. GWG was adequate (5–9kg) in 24.2%, insufficient (<5kg) in 41.8% and excessive (>9kg) in 34.2%. Birth weight was within normal range in 81.9%, 3.6% were small for gestational age (microsomia) and 14.4% were large for gestational age (macrosomia). Insufficient GWG was associated with a higher rate of microsomal offspring, excessive GWG was associated to macrosomia and adequate GWG with normal birth weight. ConclusionGWG in women with pre-pregnancy obesity and GDM impacts neonatal birthweight. Insufficient GWG is associated with microsomia and excessive GWG is associated with macrosomia. Women with adequate GWG according to the IOM guidelines obtained better perinatal outcomes.

Association between maternal weight gain during pregnancy and child's body mass index at preschool age.

Recent studies reported that prepregnancy body mass index (BMI) and weight gain during pregnancy affect birth weight and contribute to childhood obesity. However, no such data are available in Korea. This study gathered data on weight gain during pregnancy and its impact on birth weight and childhood obesity in Korea. We reviewed 1,753 singleton full-term babies born at CHA Bundang Medical Center in 2014-2016. We first review each maternal and baby factor based on prepregnancy BMI (underweight, normal, overweight/obese) and then divided them into low, normal, and excess gestational weight gain (GWG) groups based on the American Institute of Medicine (IOM) guidelines. We reviewed the characteristics of each group and analyzed the association between maternal GWG based on IOM guidelines and child BMI after 6 years. The maternal prepregnancy BMI group showed a significant difference in birth weight and child BMI at 6 years. As the prepregnancy BMI increased, the birth weight and BMI at 6 years also increased (P<0.001). Mean birth weight and child BMI at 6 years differed significantly among the GWG groups. Furthermore, excess postpartum weight gain increased the risk of childhood overweight and obesity (odds ratio, 2.21; 95% confidence interval, 1.40-3.49). Excess weight gain during pregnancy should be avoided due to its short- and long-term association with childhood obesity. Owing to the high prevalence of excess GWG and childhood obesity, excess weight gain during pregnancy can have significant public health implications.