Mediating role of gestational weight gain in the relationship between socioeconomic status and preterm birth: a Chinese population-based study.

BACKGROUND: The modifiable mechanisms underlying the association between socioeconomic status (SES) and preterm birth remain unclear. This study aimed to investigate the relationship between preterm birth and maternal SES or gestational weight gain (GWG), as well as the role of GWG in mediating SES disparities in preterm birth. METHODS: Data was from a hospital-based sub-study of physical growth and development survey for Chinese newborns with various gestational ages. Singleton newborns aged from 24 to 42weeks' gestation and their mothers were included. Using information from maternal questionnaire, a composite SES was constructed with parental education and family annual income. GWG as mediator was calculated by deducting pre-pregnancy weight from maternal weight at delivery. Logistic regression model was adopted to investigate the association of preterm birth with SES or GWG. Causal mediation analysis was performed to measure mediating effect of GWG on the pathway from SES to preterm birth. RESULTS: After controlling for potential confounders, risk of preterm birth was reduced by 12.4% (OR = 0.876, 95%CI:0.855-0.879) for per one-kilogram increase of GWG, and risk of preterm birth was reduced by 24% (OR = 0.760, 95%CI: 0.717-0.806) for per one-unit increase of SES score. Mediation analysis supported a significant association between higher SES and decreased risk of preterm partly through higher GWG, in which estimated proportion mediated by GWG was 13.04% (95%CI: 11.89-16.25). GWG also played a significant role as a mediator when socioeconomic status was indicated by maternal education, paternal education or family income. GWG mediated approximately 11.03% (95% CI: 8.56-18.25) of the total effect of SES on very preterm birth, which was greater than that for moderate preterm birth (6.72%, 95%CI: 2.72-31.52) and late preterm birth (9.04%, 95%CI: 5.24-24.04). A series of sensitive analysis confirmed the robustness of association of interest. CONCLUSION: Increased GWG and higher socioeconomic status are strongly associated with a lower risk of preterm birth. GWG mediates socioeconomic disparities in preterm birth, most notably in very preterm birth. Understanding this mechanism will aid in the development of interventions and policy for maternal and child health care.

The Effect of Prenatal Docosahexaenoic Acid Supplementation on Offspring Fat Mass and Distribution at 24 Months Old.

Background: Excessive gestational weight gain (GWG) is related to increased offspring fat accrual, and increased fat mass (FM) is related to obesity development. Prenatal DHA supplementation has been linked to lower levels of offspring FM; however, conflicting data exist. Objectives: This study aimed to determine if there is a protective effect of prenatal DHA supplementation on offspring fat accrual and adipose tissue deposition at 24 mo in offspring born to females who gain excessive weight compared with nonexcessive weight during pregnancy. We also explored if the effect of DHA dose on FM differed by offspring sex. Methods: Infants born to females who participated in the Assessment of DHA on Reducing Early Preterm Birth randomized controlled trial (ADORE) were recruited. In ADORE, females were randomly assigned to either a high or low prenatal DHA supplement. Offspring body composition and adipose tissue distribution were measured using dual-energy x-ray absorptiometry (DXA). GWG was categorized as excessive or not excessive based on clinical guidelines. Results: For total FM, there was a significant main effect for the DHA dose (P = 0.03); however, the dose by GWG status was nonsignificant (P = 0.44). Therefore, a higher prenatal DHA dose was related to greater offspring FM (622.9 g greater) and unrelated to GWG status. When investigating a DHA dose by sex effect, a significant main effect for DHA dose (P = 0.01) was detected for central FM. However, no interaction was detected (P = 0.98), meaning that both boys and girls had greater central FM if their mother was assigned to the higher DHA dose. Conclusions: Greater prenatal DHA supplementation was associated with greater offspring FM and adipose tissue distribution at 24 mo. It will be important to understand if these effects persist into childhood.This trial was registered at clinicaltrials.gov as NCT03310983.

Differing intensities of a midwife-led antenatal healthy lifestyle service on maternal and neonatal outcomes: A retrospective cohort study.

INTRODUCTION: Maternal obesity and excessive gestational weight gain are associated with adverse maternal and neonatal outcomes. There is uncertainty over the most effective antenatal healthy lifestyle service, with little research determining the impact of different lifestyle intervention intensities on pregnancy outcomes. METHOD: This retrospective cohort study compared pregnancy and birth outcomes in women with a body mass index of 40 or above who were offered a low intensity midwife-led antenatal healthy lifestyle service (one visit) with women who were offered an enhanced service (three visits). The primary outcome was gestational weight gain. RESULTS: There were no differences between the two healthy lifestyle service intensities (N = 682) in the primary outcome of mean gestational weight gain [adjusted mean difference (aMD) -1.1 kg (95 % CI -2.3 to 0.1)]. Women offered the enhanced service had lower odds of gaining weight in excess of Institute of Medicine recommendations [adjusted odds ratio (aOR) 0.63 (95 % CI 0.40-0.98)] with this reduction mainly evident in multiparous women. Multiparous women also gained less weight per week [aMD -0.06 kg/week (95 % CI -0.11 to -0.01)]. No overall beneficial effects were seen in maternal or neonatal outcomes measured such as birth weight [aMD 25 g (95 % CI -71 to 121)], vaginal birth [aOR 0.87 (95 % CI 0.64-1.19)] or gestational diabetes mellitus [aOR 1.42 (95 % CI 0.93-2.17)]. However, multiparous women receiving the enhanced service had reduced odds of small for gestational age [aOR 0.52 (95 % CI 0.31-0.87)]. This study was however underpowered to detect differences in some outcomes with low incidences. DISCUSSION: Uncertainty remains over the best management of women with severe obesity regarding effective interventions in terms of intensity. It is suggested that further research needs to consider the different classes of obesity separately and have a particular focus on the needs of nulliparous women given the lack of effectiveness of this service among these women.

Total Gestational Weight Gain Is Explained by Leptin and Body Fat, Regardless of Pre-Pregnancy Body Mass Index and Other Adipokines, in Mexican Adolescents.

Pre-pregnancy body mass index (pBMI) is a predictor of gestational weight gain (GWG). However, other factors, such as adipokines and inflammation markers, may also be associated with GWG. The aim of the study was to determine the association of leptin, adiponectin, irisin, and C-reactive protein, with GWG in adolescents. A longitudinal study was conducted from 2018 to 2023 in adolescents with a clinically healthy pregnancy. The assessments included sociodemographic and clinical data, pBMI, percent of body fat, serum concentrations of leptin, adiponectin, irisin, and high-sensitivity C-reactive protein (hsCRP), and total GWG adequacy. Cox regression models were performed, the outcome variables were inadequate and excessive GWG. In 198 participants, being overweight/obesity was marginally associated with a protective effect against inadequate GWG (HR = 0.44, 95%CI = 0.18-1.06), regardless of maternal characteristics and adipokines. Leptin (HR = 1.014, 95%CI = 1.008-1.021), and body fat percent (HR = 1.11, 95%CI = 1.05-1.17) were associated with a higher risk of excessive GWG, independent of other maternal variables such as pBMI, while adiponectin was associated with a lower risk. These findings suggest that, in Mexican adolescents, adipose tissue and its adipokines during pregnancy may play a more significant role in the final GWG than body weight.

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

BACKGROUND: Optimal gestational weight change (GWC) is little known among pregnant women with gestational diabetes mellitus (GDM). OBJECTIVE: This study aimed to explore the optimal GWC ranges for women with GDM and validate these ranges compared to the Institute of Medicine (IOM) guidelines. METHODS: A 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. RESULTS: The 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. CONCLUSIONS: The 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.

Gestational weight gain as a mediator of the relationship between pre-pregnancy body mass index and the risk of preterm birth: A four-way decomposition analysis.

OBJECTIVE: The aim of the present study was to examine and quantify whether the association between preterm birth (PTB) and pre-pregnancy body mass index (BMI) is mediated by gestational weight gain (GWG). METHODS: This is a secondary analysis of a large randomized community non-inferiority trial using a cohort design. The data of 26 101 pregnant women in their first trimester who sought prenatal care and met eligibility criteria were included. The four-way decomposition method was applied to screen for all types of association effects of pre-pregnancy BMI on the risk of PTB. These effects include the total, direct, and various indirect effects including pure mediation via GWG, interactive effects with GWG, and mediated interaction with GWG, all adjusted for potential confounders. RESULTS: Among the study participants, 24 461 (93.7%) had term deliveries, while 1640 (6.3%) experienced PTB. The results of the study showed that there was a positive association between pre-pregnancy BMI among those with BMI more than 25 kg/m2 and the risk of PTB and this association was negatively mediated and interacted by GWG, which differed quantitatively between those who had inadequate, adequate, or excessive GWG. The total association effect showed that the risk was lowest for those who had underweight pre-pregnancy BMI and adequate GWG (excess relative risk [RR]: 0.06, 95% CI: 0.01-0.11, P value: 0.022) and was highest for those who had obese pre-pregnancy BMI and excessive GWG (excess RR: 0.67, 95% CI: 0.35-1.00, P value <0.001). CONCLUSION: The findings of the present prospective population-based study demonstrated that pre-pregnancy BMI >25 kg/m2 is directly and positively associated with the risk of preterm birth. The highest risk of preterm birth was observed among individuals with an obese pre-pregnancy BMI who also experienced excessive GWG.

Practical weight management to minimize pregnancy complications and promote women's health: the possibility of interpregnancy care.

Pregnancy is an excellent opportunity to provide medical interventions to women. It is also a stress test used to predict health. Numerous studies have demonstrated that the pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) are critical factors for pregnancy complications such as hypertensive disorders of pregnancy (HDP), gestational diabetes mellitus (GDM), large or small gestational age infants, and spontaneous preterm birth (sPTB). These complications are associated with an increased risk of cardiovascular disease (CVD), which is a leading cause of mortality in women. In addition, complications adversely affect the short- and long-term prognoses of children. Optimal GWG to reduce complications is recommended based on pre-pregnancy BMI; however, racial differences should also be noted. The values in the Japanese guidelines are lower than those in the American Institute of Medicine guidelines. The Asian BMI thresholds for CVD risk are also lower than those in Europe. Therefore, weight management should be based on racial/genetic background. Interpregnancy weight gain or loss has also been reported to be associated with the risk of pregnancy complications; however, few studies have been conducted in Asian populations. Our previous reports suggested that avoiding an excess of 0.6 kg/m2/year of annual BMI gain may reduce the risk of HDP or GDM, and insufficient gain of < 0.25 kg/m2/year may increase sPTB recurrence. Annual BMI is useful for practical weight control during interpregnancy. Based on these findings, effective approaches should be established to improve the health of women and their offspring.

Contribution of gestational weight gain to childhood asthma phenotypes: a prospective cohort study.

BACKGROUND: The contribution of prenatal anthropometric measures to the development of specific childhood asthma phenotypes is not known. OBJECTIVE: We aimed to evaluate associations between prepregnancy body mass index (BMI) and gestational weight gain (GWG) with allergic and non-allergic asthma phenotypes in childhood. METHODS: Our study population included term, healthy infants in the middle Tennessee region of the United States. Prepregnancy BMI and GWG were ascertained from questionnaires administered during early infancy and categorized based on World Health Organization (WHO) and Institute of Medicine (IOM) recommendations, respectively. Allergic asthma was defined as 5-year current asthma and a positive skin test or specific IgE to aeroallergen(s). We used multivariable logistic regression models for asthma and multinomial logistic regression models for non-asthma, allergic asthma, and non-allergic asthma. RESULTS: A total of 1,266 children were included. At the 5-year follow-up, 194 (15.3%) had asthma; among them, 102 (52.6%) had allergic asthma. Both inadequate and excessive GWG, compared to adequate GWG, were associated with increased odds of asthma (inadequate: aOR 1.76 [95% CI: 1.03-2.98]; excessive: aOR 1.70 [95% CI: 1.12-2.57]) and increased odds of allergic asthma compared to no asthma (inadequate: aOR 3.49 [95% CI: 1.66-7.32]; excessive: aOR 2.55 [95% CI: 1.34-4.85]). Prepregnancy BMI was not associated with asthma nor with asthma phenotypes. CONCLUSION: Both inadequate and excessive GWG were associated with allergic asthma risk. These results support the benefits of optimal GWG during pregnancy on child health outcomes.

Serum Folate, Red Blood Cell Folate, and Zinc Serum Levels Are Related with Gestational Weight Gain and Offspring's Birth-Weight of Adolescent Mothers.

BACKGROUND: Gestational weight gain below or above the Institute of Medicine recommendations has been associated with adverse perinatal and neonatal outcomes. Very few studies have evaluated the association between serum and red blood cell folate concentrations and gestational weight gain in adolescents. Additionally, zinc deficiency during pregnancy has been associated with impaired immunity, prolonged labor, preterm and post-term birth, intrauterine growth restriction, low birth weight, and pregnancy-induced hypertension. OBJECTIVE: The purpose of our study is to evaluate the association between serum concentrations of zinc, serum folate, and red blood cell folate, with the increase in gestational weight and the weight and length of the newborn in a group of adolescent mothers from Mexico City. RESULTS: In our study, 406 adolescent-neonate dyads participated. The adolescents' median age was 15.8 years old. The predominant socioeconomic level was middle-low (57.8%), single (57%), 89.9% were engaged in home activities, and 41.3% completed secondary education. Excessive gestational weight gain was observed in 36.7% of cases, while insufficient gestational weight gain was noted in 38.4%. Small for gestational age infants were observed in 20.9% of the sample. Low serum folate (OR 2.1, 95% CI 1.3-3.3), decreased red blood cell folate (OR 1.6, 95% CI 1.0-2.6), and reduced serum zinc concentrations (OR 3.3, 95% CI 2.1-5.2) were associated with insufficient gestational weight gain. Decreased serum zinc levels (OR 1.2, 95% CI 1.2-3.4) were linked to an increased probability of delivering a baby who is small for their gestational age. CONCLUSIONS: Low serum folate, red blood cell folate, and serum zinc concentrations were associated with gestational weight gain and having a small gestational age baby. Both excessive and insufficient gestational weight gain, as well as having a small gestational age baby, are frequent among adolescent mothers.

Gestational weight gain and its determinants among pregnant women in Gurage zone, Central Ethiopia: a cohort study.

BACKGROUND: The nutritional status of the mothers before pregnancy and the weights gained during pregnancy are very crucial factors affecting the pregnancy outcomes and health of the infants. This study aimed to assess early pregnancy weight, determine the magnitude of gestational weight gain, and investigate the factors affecting gestational weight gain among pregnant women in the Gurage zone, 2022. METHODS: A prospective cohort study was conducted among pregnant women who started antenatal care follow-up before the 16th week of gestation in the selected hospitals and health centers of the Gurage zone, Ethiopia. The gestational weight gain was obtained by subtracting the early pregnancy weight from the last pregnancy weight and categorizing based on the Institute of Medicine (IOM) recommendation. RESULTS: The early pregnancy weight status of the women at enrollment indicates that 10% of them were underweight and 83% of them had normal weight. On average, the study participants gained 13.3 kgs of weight with [95% CI: 13.0, 13.6]. More than half (56%) of them gained adequate weight, a quarter (26%) of them gained inadequate weight, and 18% of them gained excess weight during pregnancy compared to the IOM recommendation. Maternal age, occupational status, and early pregnancy weight status were found to have a statistically significant association with the gestational weight gained. CONCLUSION: Almost half (44%) of the pregnant women gained either inadequate or excess weight during pregnancy. Promoting gestational weight gain within recommended guidelines should be emphasized for younger, employed women and those who are either underweight or overweight.

Gestational weight gain and adverse birth outcomes in South African women with HIV on antiretroviral therapy and without HIV: a prospective cohort study.

INTRODUCTION: Outside of pregnancy, evidence shows that persons with HIV initiating or switching to dolutegravir (DTG)-based antiretroviral therapy (ART) experience greater weight gain compared to those on other ART classes. However, there are few data on the impact of DTG-based ART on gestational weight gain (GWG) in sub-Saharan Africa where HIV is most common. According to the National Academy of Medicine (NAM), GWG below and above NAM guidelines is associated with adverse birth outcomes. Therefore, the objective of this study was to describe GWG by HIV status and ART regimen, and examine the associations with adverse birth outcomes. METHODS: We enrolled pregnant women with HIV (WHIV) and without HIV (≥18 years) in a peri-urban primary healthcare facility in Cape Town, South Africa between 2019 and 2022. GWG was study-measured at 24-28 (baseline) and 33-38 weeks gestation and converted to GWG rate (kg/week) in accordance with NAM guidelines. GWG z-scores were generated using the INTEGROWTH-21 and US standards to account for differing lengths of gestation. Birth outcome data were obtained from medical records. Associations of GWG z-score with adverse birth outcomes were assessed using multivariable linear or log-binomial regression. RESULTS: Among 292 participants (48% WHIV), median age was 29 years (IQR, 25-33), median pre-pregnancy body mass index (BMI) was 31 kg/m2 (IQR, 26-36) and 20% were primiparous at baseline. The median weekly rate of GWG was 0.30 kg/week (IQR, 0.12-0.50), 35% had GWG below NAM standards (59% WHIV) and 48% had GWG above NAM standards (36% WHIV). WHIV gained weight more slowly (0.25 vs. 0.37 kg/week, p<0.01) than women without HIV. Weekly rate of GWG did not differ by ART regimen (DTG-based ART 0.25 vs. efavirenz-based ART 0.27 kg/week, p = 0.80). In multivariable analyses, GWG z-score was positively associated with continuous birth weight (mean difference = 68.53 95% CI 8.96, 128.10) and categorical high birth weight of >4000 g (RR = 2.18 95% CI 1.18, 4.01). CONCLUSIONS: Despite slower GWG among WHIV, nearly half of all women gained weight faster than recommended by the NAM. GWG was positively associated with infant birth weight. Interventions to support healthy GWG in sub-Saharan Africa are urgently needed.

A Systematic Review and Bayesian Network Meta-Analysis Comparing In-Person, Remote, and Blended Interventions in Physical Activity, Diet, Education, and Behavioral Modification on Gestational Weight Gain among Overweight or Obese Pregnant Individuals.

BACKGROUND: Despite the well-documented adverse outcomes associated with obesity during pregnancy, this condition remains a promising modifiable risk factor. OBJECTIVES: The aim of this study was to ascertain the most effective treatment modalities for gestational weight gain (GWG) in pregnant women classified as overweight or obese. METHODS: A systematic search was conducted across 4 electronic databases: Embase, EBSCOhost, PubMed, and Web of Science. To assess the quality of evidence, the Confidence In Network Meta-Analysis (CINeMA) approach, grounded in the Grading of Recommendations Assessment, Development, and Evaluation framework, was employed. A Bayesian network meta-analysis was conducted to synthesize the comparative effectiveness of treatment modalities based on GWG outcomes. RESULTS: The analysis incorporated 60 randomized controlled trials, encompassing 16,615 participants. Modes of intervention administration were classified as remote (R: eHealth [e] and mHealth [m]), in-person (I), and a combination of both (I+R). The interventions comprised 5 categories: education (E), physical activity (PA), dietary (D), behavior modification (B), and combinations thereof. The quality of the evidence, as evaluated by CINeMA, ranged from very low to high. Compared to the control group, the I-D intervention (mean difference [MD]: -1.27; 95% confidence interval [CI]: -2.23, -0.32), I-PADB (MD: -0.60, 95% CI: -1.19, -0.00), and I-B (MD: -0.34, 95% CI: -0.57, -0.10) interventions showed significant efficacy in reducing GWG. CONCLUSIONS: Preliminary findings suggest that the I-D intervention is the most efficacious in managing GWG among pregnant women who are overweight or obese, followed by I-PADB and I-B+R-B(m) treatments. These conclusions are drawn from evidence of limited quality and directness, including insufficient data on PA components used in the interventions. Owing to the absence of robust, direct evidence delineating significant differences among various GWG management strategies, it is tentatively proposed that the I-D intervention is likely the most effective approach. This study was registered with PROSPERO as CRD42023473627.

Barriers and facilitators to healthy gestational weight gain amongst pregnant women from ethnic minority groups: A systematic search and narrative synthesis.

BACKGROUND: Excessive weight gain can be detrimental to the health and wellbeing of both mother and child. There is evidence that women from ethnic minority groups are more likely to gain excessive weight during pregnancy. For the purpose of this review, ethnic minority women are defined as those with different national or cultural traditions from the main population. AIM: Our aim was to identify barriers and facilitators to healthy gestational weight gain in pregnant women in ethnic minority groups. METHODS: Databases searched were MEDLINE, CINAHL, PsycInfo and PsycArticles between 2011 and 2022. Inclusion criteria were empirical studies of any method considering gestational weight gain in ethnic minority women published in English. Data were extracted according to aim, participants, methods, and findings in relation to barriers and facilitators. Included papers were assessed for quality according to relevant Joanna Briggs Institute checklists. FINDINGS: Twenty-six studies were identified. Five themes were revealed: (1) knowledge and beliefs, (2) cultural and social influences, (3) confidence, (4) physical experiences, and (5) personal and environmental factors. DISCUSSION: Some barriers and facilitators were relevant to all groups and others were more specific to ethnic minority groups. The latter included social and cultural influences, which were reported extensively. Our search was comprehensive, although it is possible we may not have captured all relevant papers. CONCLUSION: We recommend that the barriers and facilitators identified here are considered in designing future, or adjusting current, health care practitioner mediated interventions to support healthy gestational weight gain in ethnic minority women.

Polybrominated diphenyl ethers and gestational weight gain: a multi-center prospective cohort study.

OBJECTIVE: To evaluate the associations of plasma polybrominated diphenyl ether (PBDE) concentrations in early pregnancy with gestational weight gain (GWG). DESIGN: Prospective cohort study. SETTING: US-based, multicentre cohort of pregnant women. POPULATION: We used data from 2052 women without obesity and 397 women with obesity participating in the NICHD Fetal Growth Studies - Singleton Cohort, with first-trimester plasma PBDE concentrations and weight measurements throughout pregnancy. METHODS: We applied generalised linear models and Bayesian kernel machine regression (BKMR) to evaluate both the individual and joint associations of PBDEs with measures of GWG, adjusting for potential confounders. MAIN OUTCOME MEASURES: Total GWG (kg), total and trimester-specific GWG velocities (kg/week), and GWG categories and trajectory groups. RESULTS: Mean pre-pregnancy BMIs were 23.6 and 34.5 kg/m2 for women without and with obesity, respectively. Among women without obesity, there were no associations of PBDEs with any GWG measure. Among women with obesity, one standard deviation increase in log-transformed PBDE 47 was associated with a 1.87 kg higher total GWG (95% CI 0.39-3.35) and a 0.05 kg/week higher total GWG velocity (95% CI 0.01-0.09). Similar associations were found for PBDE 47 in BKMR among women with obesity, and PBDE 47, 99 and 100 were associated with lower odds of being in the low GWG trajectory group. CONCLUSIONS: PBDEs were not associated with GWG among individuals without obesity. Among those with obesity, only PBDE 47 showed consistent positive associations with GWG measures across multiple statistical methods. Further research is needed to validate this association and explore potential mechanisms.

Perinatal Outcomes of Diet Therapy in Gestational Diabetes Mellitus Diagnosed before 24 Gestational Weeks.

To evaluate perinatal outcomes and risk factors for large for gestational age (LGA; birth weight over 90 percentile) in gestational diabetes diagnosed before 24 gestational weeks and treated with diet therapy alone until delivery (Diet Early gestational diabetes mellitus (Diet Early GDM)), we assessed the maternal characteristics and perinatal outcomes of patients with early GDM (n = 309) and normal glucose tolerance (NGT; n = 309) at Keio University Hospital. The gestational weight gain (GWG) expected at 40 weeks was significantly lower in the Diet Early GDM group than in the NGT group. The Diet Early GDM group exhibited a significantly lower incidence of low birth weight (<2500 g) and higher Apgar score at 5 min than the NGT group. Multiple logistic regression analysis revealed that the pre-pregnancy body mass index and GWG expected at 40 weeks were significantly associated with LGA for Diet Early GDM. No differences were observed in random plasma glucose levels in the first trimester, 75 g oral glucose tolerance test values, and initial increase or subsequent decrease between the two groups. Dietary early GDM did not exhibit a worse prognosis than NGT. To prevent LGA, it might be important to control maternal body weight not only during pregnancy but also before conception.

[Effect of gestational weight gain on growth trajectory in children aged 0 to 3 years].

OBJECTIVE: To describe the growth trajectory of body mass index for age Z score(BAZ) in children aged 0 to 3 years and to explore the association between gestational weight gain and BAZ growth trajectory. METHODS: Based on a prospective cohort study, we recruited pregnant women in their early pregnancy into this study from 2013 to 2017 in Taicang of Jiangsu Province, tracked their weight changes until they gave birth, and calculated and evaluated their gestational weight gain(GWG) as appropriate, inadequate or excessive GWG based on Chinese GWG standard. Children's height/length and weight were measured at birth, 1, 3, 6, 8, 12, 18, 24, 30 and 36 months of age, and their BAZ scores were calculated. Group-based trajectory modeling(GBTM) was used for fitting BAZ trajectories. Multilevel Logistic regression was used to analyze the association between the level of GWG and BAZ growth trajectories. RESULTS: There were 1864 mother-child pairs in the study, and three groups of BAZ trajectories were fitted including slow growth trajectory(34.07%), appropriate growth trajectory(48.23%), and fast growth trajectory(17.70%). In univariate analysis, compared with children whose mothers had appropriate GWG, the children whose mothers had inadequate GWG were more likely in the group of slow growth trajectory(OR = 1.95, 95%CI 1.28-2.96), and the children whose mothers had excessive GWG were more likely in the group of fast growth trajectory(OR = 1.57, 95% CI 1.19-2.07). After adjusting for maternal pre-pregnancy body mass index(BMI) and parity, and the child's gender and birth weight, the children whose mothers gained in adequate GWG were more likely in the group of slow growth trajectory(OR = 1.84, 95%CI 1.19-2.84), while the association between excessive GWG and fast growth trajectory was not statistically significant(OR = 1.26, 95%CI 0.94-1.68). CONCLUSION: The BAZ trajectories of children aged 0-3 years can be categorized into slow, appropriate, and fast growth groups, and children's slow growth was associated with maternal inadequate GWG.

Genomic Insights into Gestational Weight Gain: Uncovering Tissue-Specific Mechanisms and Pathways.

Increasing gestational weight gain (GWG) is linked to adverse outcomes in pregnant persons and their children. The Early Growth Genetics (EGG) Consortium identified previously genetic variants that could contribute to early, late, and total GWG from fetal and maternal genomes. However, the biologic mechanisms and tissue-Specificity of these variants in GWG is unknown. We evaluated the association between genetically predicted gene expression in five relevant maternal (subcutaneous and visceral adipose, breast, uterus, and whole blood) from GTEx (v7) and fetal (placenta) tissues and early, late, and total GWG using S-PrediXcan. We tested enrichment of pre-defined biological pathways for nominally (P < 0.05) significant associations using the GENE2FUNC module from Functional Mapping and Annotation of Genome-Wide Association Studies. After multiple testing correction, we did not find significant associations between maternal and fetal gene expression and early, late, or total GWG. There was significant enrichment of several biological pathways, including metabolic processes, secretion, and intracellular transport, among nominally significant genes from the maternal analyses (false discovery rate p-values: 0.016 to 9.37×10). Enriched biological pathways varied across pregnancy. Though additional research is necessary, these results indicate that diverse biological pathways are likely to impact GWG, with their influence varying by tissue and weeks of gestation.

Association between maternal gestation weight gain and preterm birth according to pre-pregnancy body mass index and HbA1c.

BACKGROUND: To investigate the association between gestational weight gain (GWG) and preterm birth (PTB) according to pre-pregnancy body mass index (pp-BMI) and glycated haemoglobin (HbA1c) within the normal range. METHODS: We conducted a population-based retrospective cohort study between July 2017 and January 2020 at Women's Hospital, Zhejiang University School of Medicine. Women were classified into three groups (inadequate GWG, appropriate GWG, and excessive GWG). In addition, women were divided into different subgroups according to pp-BMI and HbA1c. We estimated the odds ratios (OR) with 95% confidence intervals (CI) to assess the associations between GWG and the risk of PTB. Meanwhile, we adjusted for possible confounding factors, including maternal age, infant sex, family history of diabetes, education, pregnancy mode, delivery mode, parity, and gravidity. RESULTS: The study involved 23,699 pregnant women, of which 1124 (4.70%) were PTB. Women who had inadequate GWG were found to have a significantly higher risk of PTB compared to women with appropriate GWG. In contrast, women with excessive GWG had a reduced risk of PTB. Similarly, GWG and PTB had similar risk associations in the HbA1c and pp-BMI subgroups. Among women with pp-BMI <18.5 kg/m2, women with inadequate GWG had a significantly increased risk of PTB compared with women in the control group (HbA1c 4.6-5.0%, appropriate GWG), and the risk increased with increasing HbA1c levels. Similar results were observed in women with normal pp-BMI. CONCLUSIONS: There was a significant association between GWG and the risk of PTB, but the risk varied by pp-BMI and HbA1c levels. Reasonable weight gain during pregnancy is essential to prevent PTB. Furthermore, while HbA1c is within the normal range, the higher levels should be noticed.

Preterm birth (PTB) rates have recently increased in China, drawing increased attention from physicians and society. Even though various risk factors for PTB have been well known, risk factors for PTB still need to be explored. This study aimed to investigate the association between gestational weight gain (GWG) and preterm birth (PTB) according to pre-pregnancy body mass index (pp-BMI) and glycated haemoglobin (HbA1c) within the normal range. Our research revealed that the underweight (pp-BMI <18.5 kg/m²) and normal weight (pp-BMI 18.5­24.9 kg/m²) groups' risk of preterm birth increased with rising HbA1c levels when GWG was inadequate. Despite HbA1c within the normal range, higher levels of HbA1c should be considered. As a result, among women with inadequate GWG, high levels of HbA1c confer a higher risk of PTB, which could alert clinicians to carry out early intervention to prevent PTB.

Reliability and validity of the Japanese version of the Pregnancy and Weight Gain Attitude Scale.

This study aimed to develop the Japanese version of the Pregnancy and Weight Gain Attitude Scale (J-PWGAS) as a measurement of body image regarding body weight and shape during pregnancy. This cross-sectional study was conducted at a perinatal medical center in Osaka, Japan, between March and November 2020. We recruited pregnant women in their second or third trimester, who were 20 years old or older and without pregnancy complications. This study evaluated the criterion validity, construct validity, internal consistency, and test-retest reliability. Of the participants, 218 and 102 women participated in the validation and test-retest reliability studies, respectively. An exploratory factor analysis revealed a 17-item, five-factor structure. The J-PWGAS indicated acceptable criterion validity, internal consistency, and test-retest reliability. The J-PWGAS can measure attitudes toward gestational weight gain in Japanese pregnant women and would be useful in examining the association of body image with weight gain and psychological status during pregnancy.

Rethinking causal assumptions about maternal BMI, gestational weight gain, and adverse pregnancy outcomes.

BACKGROUND: The aim of this study was to evaluate commonly assumed causal relationships between body mass index (BMI), gestational weight gain (GWG), and adverse pregnancy outcomes, which have formed the basis of guidelines and interventions aimed at limiting GWG in women with overweight or obesity. We explored relationships between maternal BMI, total GWG (as a continuous variable and as 'excessive' GWG), and pregnancy outcomes (including infant birthweight measures and caesarean birth). METHODS: Analysis of individual participant data (IPD) from the i-WIP (International Weight Management in Pregnancy) Collaboration, from randomised trials of diet and/or physical activity interventions during pregnancy reporting GWG and maternal and neonatal outcomes. Women randomised to the control arm of 20 eligible randomised trials (4370 of 8908 participants) from the i-WIP dataset of 36 randomised trials (total 12,240 women). The main research questions were to characterise the relationship between maternal BMI and (a) total GWG, (b) the risk of 'excessive' GWG (using the Institute of Medicine's guidelines), and (c) adverse pregnancy outcomes as mediated via GWG versus other pathways to determine the extent to which the observed effect of maternal BMI on pregnancy outcomes is mediated via GWG. We utilised generalised linear models and regression-based mediation analyses within an IPD meta-analysis framework. RESULTS: Mean GWG decreased linearly as maternal BMI increased; however, the risk of 'excessive' GWG increased markedly at BMI category thresholds (i.e. between the normal and overweight BMI category threshold and between the overweight and obese BMI category threshold). Increasing maternal BMI was associated with increased risk of all pregnancy outcomes assessed; however, there was no evidence that this effect was mediated via effects on GWG. CONCLUSIONS: There is evidence of a meaningful relationship between maternal BMI and GWG and between maternal BMI and adverse pregnancy outcomes. There is no evidence that the effect of maternal BMI on outcomes is via an effect on GWG. Our analyses also cast doubt on the existence of a relationship between 'excessive' GWG and adverse pregnancy outcomes. Our findings challenge the practice of actively managing GWG throughout pregnancy.