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.

Contribution of greenness, air pollution, and residential food environment to excess gestational weight gain: A cross-sectional study in Wuhan, China.

OBJECTIVES: Our goal was to explore how greenness, air pollution, and residential food environment were linked to excessive gestational weight gain (EGWG), and to estimate their combined effects on this condition. METHOD: This cross-sectional analysis included 51,507 pregnant women from the Wuhan Maternal and Child Health Management Information System between 2016 and 2019. Generalized linear mixed regression models were employed to explore the relationships between greenness, air pollution, residential food environmental exposure, and EGWG; and the combined effects were further estimated by cluster analysis and principal components analysis. RESULT: We only found a significant association between convenience store density within the 250 m buffer zone (OR = 1.03 and 95% CI: 1.01,1.05) and EGWG. In terms of air pollution, sulfur dioxide(SO2), particulate matter with a diameter of 10 µm or less(PM10), and particulate matter with a diameter of 2.5 µm or less(PM2.5) were substantially correlated with a higher prevalence of EGWG and higher GWG, with (OR = 1.16 and 95% CI: 1.12,1.21; OR = 1.12 and 95% CI: 1.08,1.16; OR = 1.17 and 95% CI: 1.14,1.21, respectively) per interquartile range(IQR) increase. Cluster analysis revealed the presence of three clusters representing urban exposures. In contrast to urban environment clusters characterized by favourable conditions, those exhibiting elevated air pollution levels, high-density residential food environment and low levels of greenness were found to have increased odds of EGWG (OR = 1.10, 95% CI: 1.03, 1.19). CONCLUSION: This study emphasizes that exposure to elevated air pollution, high-density residential neighbourhood food environments, and low levels of greenness is a neighbourhood obesogenic environment for pregnant women.

Association between sleep duration and quality with food intake, chrononutrition patterns, and weight gain during pregnancy.

To analyse the association between sleep duration and quality with food intake, chrononutrition patterns, and weight gain during pregnancy. A prospective cohort study was conducted with 100 pregnant women. Data collection occurred once during each gestational trimester. The assessment of sleep quality and duration was performed using the Pittsburgh Sleep Quality Index. Food intake was assessed using three 24-h recalls in each trimester. Body weight was measured during the three trimesters, and height was measured only once to calculate the BMI. Linear regression analyses were performed to associate sleep duration and quality with food consumption and weight gain variables. Longer sleep duration was associated with a later dinner in the first trimester (ß = 0·228, P = 0·025) and earlier in the third trimester (ß = -0·223, P = 0·026), in addition to a later morning snack in the second trimester (ß = 0·315, P = 0·026). Worse sleep quality was associated with higher total energy intake (ß = 0·243, P = 0·044), total fat (ß = 0·291, P = 0·015) and the chrononutrition variables such as a higher number of meals (ß = 0·252, P = 0·037), higher energetic midpoint (ß = 0·243, P = 0·044) and shorter fasting time (ß = -0·255, P = 0·034) in the third trimester. Sleep quality was also associated with a higher BMI in the first trimester of pregnancy (ß = 0·420, P = < 0·001). Most of the associations found in the present study show that poor sleep is associated with higher energy and fat intake and higher BMI. Longer sleep duration was associated with a later dinner in early pregnancy and an earlier dinner in late pregnancy, as well as with a later morning snack in the second trimester of pregnancy.

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.

Body mass index and weight gain in pregnancy and cardiovascular health in middle age: A cohort study.

OBJECTIVE: To examine associations between body mass index (BMI) in early pregnancy and gestational weight gain (GWG) with cardiovascular health in middle age using the 'Life's Essential 8' (LE8) concept of the American Heart Association (AHA). DESIGN: Population-based cohort study. SETTING: Swedish CardioPulmonary bioImage Study (SCAPIS). POPULATION: A total of 8871 women from SCAPIS were included. METHODS: Information on cardiovascular health in middle age was collected from SCAPIS and linked to pregnancy weight data obtained from the Swedish Medical Birth Register, with an average follow-up time of 24.5 years. An LE8 score between 0 and 100 was determined, where a score under 60 points was defined as poor cardiovascular health. Binary logistic regression and restricted cubic splines were used. MAIN OUTCOME MEASURES: Cardiovascular health according to LE8 in middle age. RESULTS: The odds of having poor cardiovascular health in middle age were significantly higher in women who had overweight (adjusted odds ratio, aOR 3.30, 95% CI 2.82-3.88) or obesity (aOR 7.63, 95% CI 5.86-9.94), compared with women classified as being of normal weight in pregnancy. Higher odds were also found for excessive GWG (aOR 1.31, 95% CI 1.09-1.57), compared with women who gained weight within the recommendations. CONCLUSIONS: A high BMI in early pregnancy and excessive GWG were associated with greater odds of poor cardiovascular health in middle age. Although further studies are needed, our results highlight pregnancy as an important period to support long-term cardiovascular health.

Mediating effect of gestational weight gain on the preventive effect of exercise during pregnancy on macrosomia: a randomized clinical trial.

OBJECTIVE: We sought to investigate the impact of individualized exercise guidance during pregnancy on the incidence of macrosomia and the mediating effect of gestational weight gain (GWG). DESIGN: A prospective randomized clinical trial. SETTING: A Hospital in Xingtai District, Hebei Province. POPULATION: Older than 20 years of age, mid-pregnancy, and singleton pregnant women without contraindications to exercise during pregnancy. METHODS: A randomized clinical trial was conducted from December 2021 to September 2022 to compare the effects of standard prenatal care with individualized exercise guidance on the incidence of macrosomia. MAIN OUTCOME MEASURE: Incidence of macrosomia. RESULTS: In all, 312 singleton women were randomized into an intervention group (N = 162) or a control group (N = 150). Participants who received individualized exercise guidance had a significantly lower incidence of macrosomia (3.73% vs. 13.61%, P = 0.002) and infants large for gestational age (9.94% vs. 19.73%, P = 0.015). However, no differences were observed in the rate of preterm birth (1.86% vs. 3.40%, P = 0.397) or the average gestational age at birth (39.14 ± 1.51 vs. 38.69 ± 1.85, P = 0.258). Mediation analysis revealed that GWG mediated the effect of exercise on reducing the incidence of macrosomia. CONCLUSION: Individualized exercise guidance may be a preventive tool for macrosomia, and GWG mediates the effect of exercise on reducing the incidence of macrosomia. However, evidence does not show that exercise increases the rate of preterm birth or affects the average gestational age at birth. TRIAL REGISTRATION: The trial is registered at www.clinicaltrails.gov [registration number: NCT05760768; registration date: 08/03/2023 (retrospectively registered)].

Maternal metabolic profiling across body mass index groups: An exploratory longitudinal study.

INTRODUCTION: Increased BMI has been identified as a risk factor for most pregnancy complications, but the underlying metabolic factors mediating the detrimental effects of BMI are largely unknown. We aimed to compare metabolic profiles in overweight/obese women (body mass index [BMI] ≥ 25 kg/m2 ) and normal weight/underweight women (BMI < 25 kg/m2 ) across gestation. We also explored how gestational weight gain (GWG) affected maternal metabolic profiles. MATERIAL AND METHODS: Exploratory nested case-control study based on a prospective longitudinal cohort of women who were healthy prior to pregnancy and gave birth at Oslo University Hospital from 2002 to 2008. The sample consisted of 48 women who were overweight/obese and 59 normal-weight/underweight women. Plasma samples from four time points in pregnancy (weeks 14-16, 22-24, 30-32 and 36-38) were analyzed by nuclear magnetic resonance spectroscopy and 91 metabolites were measured. Linear regression models were fitted for each of the metabolites at each time point. RESULTS: Overweight or obese women had higher levels of lipids in very-low-density lipoprotein (VLDL), total triglycerides, triglycerides in VLDL, total fatty acids, monounsaturated fatty acids, saturated fatty acids, leucine, valine, and total branched-chain amino acids in pregnancy weeks 14-16 compared to underweight and normal-weight women. Docosahexaenoic acid and degree of unsaturation were significantly lower in overweight/obese women in pregnancy weeks 36-38. In addition, overweight or obese women had higher particle concentration of XXL-VLDL and glycoprotein acetyls (GlycA) at weeks 14-16 and 30-32. GWG did not seem to affect the metabolic profile, regardless of BMI group when BMI was treated as a dichotomous variable, ≥25 kg/m2 (yes/no). CONCLUSIONS: Overweight or obese women had smaller pregnancy-related metabolic alterations than normal-weight/underweight women. There was a trend toward higher triglyceride and VLDL particle concentration in overweight/obese women. As this was a hypothesis-generating study, the similarities with late-onset pre-eclampsia warrant further investigation. The unfavorable development of fatty acid composition in overweight/obese women, with possible implication for the offspring, should also be studied further in the future.

The implementation of online and offline hybrid weight management approach for pregnant women based on the Fogg behavior model in Hainan, China: a pilot randomized controlled trial.

OBJECTIVE: This study aimed at evaluating the effects of online and offline hybrid weight management approach based on the Fogg behavior model on total gestational weight gain and perinatal outcomes. METHODS: Pregnant women in Hainan, the southernmost province of China, were recruited into a randomized controlled trial, which was designed to develop a WeChat platform for pregnancy weight management, and implement individualized and continuous pregnancy weight management services for pregnant women under the guidance of the Fogg behavior model. All pregnant women participating in the study were included in the full analysis set (FAS) for analysis. The pregnant women who completed the intervention and provided all outcome indicators were included in the per protocol set (PPS) for outcome evaluation. RESULTS: Fifty-eight pregnant women were included in FAS analysis, and 52 pregnant women were finally included in PPS analysis. There was no statistically significant difference (P > 0.05) between the two groups at baseline. The gestational weight gain of the intervention group was significantly lower than that of the control group (P < 0.05). In the control group, the rate of appropriate weight gain during pregnancy was 48.26%, the rate of appropriate weight gain during pregnancy was 93.30% in the intervention group, with a statistically significant difference (P < 0.05). In the delivery outcomes, the cesarean section rate in the intervention group was significantly lower than that in the control group, and the differences were statistically significant (P < 0.05). The incidence of gestational diabetes mellitus and gestational hypertension in the intervention group was lower than those in the control group, and the differences were statistically significant (P < 0.05). The neonatal weight and incidence of macrosomia of the intervention group were lower than that of the control group, and the difference was statistically significant (P < 0.05). CONCLUSIONS: This study combined the individualized and continuous pregnancy weight management of the online WeChat platform and offline consultation based on the Fogg behavior model, showing great potential in improving maternal and infant outcomes. TRIAL REGISTRATION: The study was registered with www.chictr.org.cn/index.aspx , Chinese Clinical Trial Registry (ChiCTR2200066707, 2022-12-14, retrospectively registered).

The influence of maternal prepregnancy weight and gestational weight gain on the umbilical cord blood metabolome: a case-control study.

BACKGROUND: Maternal overweight/obesity and excessive gestational weight gain (GWG) are frequently reported to be risk factors for obesity and other metabolic disorders in offspring. Cord blood metabolites provide information on fetal nutritional and metabolic health and could provide an early window of detection of potential health issues among newborns. The aim of the study was to explore the impact of maternal prepregnancy overweight/obesity and excessive GWG on cord blood metabolic profiles. METHODS: A case control study including 33 pairs of mothers with prepregnancy overweight/obesity and their neonates, 30 pairs of mothers with excessive GWG and their neonates, and 32 control mother-neonate pairs. Untargeted metabolomic profiling of umbilical cord blood samples were performed using UHPLC‒MS/MS. RESULTS: Forty-six metabolites exhibited a significant increase and 60 metabolites exhibited a significant reduction in umbilical cord blood from overweight and obese mothers compared with mothers with normal body weight. Steroid hormone biosynthesis and neuroactive ligand‒receptor interactions were the two top-ranking pathways enriched with these metabolites (P = 0.01 and 0.03, respectively). Compared with mothers with normal GWG, in mothers with excessive GWG, the levels of 63 metabolites were increased and those of 46 metabolites were decreased in umbilical cord blood. Biosynthesis of unsaturated fatty acids was the most altered pathway enriched with these metabolites (P < 0.01). CONCLUSIONS: Prepregnancy overweight and obesity affected the fetal steroid hormone biosynthesis pathway, while excessive GWG affected fetal fatty acid metabolism. This emphasizes the importance of preconception weight loss and maintaining an appropriate GWG, which are beneficial for the long-term metabolic health of offspring.

The impact of gestational weight gain on fetal and neonatal outcomes: the Araraquara Cohort Study.

BACKGROUND: Gestational weight gain (GWG) is an important indicator for monitoring maternal and fetal health. OBJECTIVE: To evaluate the effect of GWG outside the recommendations of the Institute of Medicine (IOM) on fetal and neonatal outcomes. STUDY DESIGN: A prospective cohort study with 1642 pregnant women selected from 2017 to 2023, with gestational age ≤ 18 weeks and followed until delivery in the city of Araraquara, Southeast Brazil. The relationship between IOM-recommended GWG and fetal outcomes (abdominal subcutaneous tissue thickness, arm and thigh subcutaneous tissue area and intrauterine growth restriction) and neonatal outcomes (percentage of fat mass, fat-free mass, birth weight and length, ponderal index, weight adequateness for gestational age by the Intergrowth curve, prematurity, and Apgar score) were investigated. Generalized Estimating Equations were used. RESULTS: GWG below the IOM recommendations was associated with increased risks of intrauterine growth restriction (IUGR) (aOR 1.61; 95% CI: 1.14-2.27), low birth weight (aOR 2.44; 95% CI: 1.85-3.21), and prematurity (aOR 2.35; 95% CI: 1.81-3.05), and lower chance of being Large for Gestational Age (LGA) (aOR 0.38; 95% CI: 0.28-0.54), with smaller arm subcutaneous tissue area (AST) (-7.99 g; 95% CI: -8.97 to -7.02), birth length (-0.76 cm; 95% CI: -1.03 to -0.49), and neonatal fat mass percentage (-0.85%; 95% CI: -1.12 to -0.58). Conversely, exceeding GWG guidelines increased the likelihood of LGA (aOR 1.53; 95% CI: 1.20-1.96), with lower 5th-minute Apgar score (aOR 0.42; 95% CI: 0.20-0.87), and increased birth weight (90.14 g; 95% CI: 53.30 to 126.99). CONCLUSION: Adherence to GWG recommendations is crucial, with deviations negatively impacting fetal health. Effective weight control strategies are imperative.

Optimal range of gestational weight gain for singleton pregnant women: a cohort study based on Chinese specific body mass index categories.

BACKGROUND: The purpose was to explore the optimal proportion of GWG in Chinese singleton pregnant women according to Chinese specific body mass index (BMI) categories. METHODS: A retrospective cohort study with 16,977 singleton pregnant women was conducted. Among the including subjects, 2/3 of which were randomly imported into the training set for calculating the optimal GWG ranges using the percentile method, the Odd Ratio (OR) method, and the combined risk curve method. And another third of the subjects were used to evaluate the GWG ranges obtained. The detection rate of adverse outcomes of pregnant women was used to evaluate the applicability of GWG obtained. The range corresponding to the lowest detection rate is the recommended GWG range in this study. RESULTS: According to the percentile method, the suitable GWG of pregnant women with underweight, normal weight, overweight or obesity before pregnancy were 12.0 ∼ 17.5 kg, 11.0 ∼ 17.0 kg, and 9.0 ∼ 15.5 kg, respectively. According to the OR method, the suitable GWG range were 11 ∼ 18 kg, 7 ∼ 11 kg, and 6 ∼ 8 kg, respectively. According to the combined risk curve method, the suitable GWG range were 11.2 ∼ 17.2 kg, 3.6 ∼ 11.5 kg, and - 5.2 ∼ 7.0 kg, respectively. When the GWG for different BMI categories were 11 ∼ 18 kg, 7 ∼ 11 kg, and 6 ∼ 8 kg, the pregnant women have the lowest detection rate of adverse maternal and infant outcomes. CONCLUSIONS: The recommended GWG based on this study for underweight, normal, overweight or obese pregnant women were 11 ∼ 18 kg, 7 ∼ 11 kg, and 6 ∼ 8 kg, respectively.

Maternal age-specific risks for adverse birth weights according to gestational weight gain: a prospective cohort in Chinese women older than 30.

BACKGROUND: It is unclear whether the effects of abnormal gestational weight gain (GWG) on birth outcomes are differently in women with different maternal ages. This study aimed to investigate maternal age-specific association between GWG and adverse birth weights in Chinese women older than 30. METHODS: 19,854 mother-child dyads were selected from a prospective cohort study in Southwest China between 2019 and 2022. Logistic regression model was used to assess the association between GWG, which defined by the 2009 Institute of Medicine guidelines, and adverse birth weights including large- and small-for-gestational-age (LGA and SGA), stratified by maternal age (31-34 years and ≥ 35 years). RESULTS: In both maternal age groups, excessive and insufficient GWG were associated with increased odds of LGA and SGA, respectively. After women were categorized by pre-pregnancy body mass index, the associations remained significant in women aged 31-34 years, whereas for women aged ≥ 35 years, the association between excessive GWG and the risk of LGA was only significant in normal weight and overweight/obese women, and the significant effect of insufficient GWG on the risk of SGA was only observed in underweight and overweight/obese women. Moreover, among overweight/obese women, the magnitude of the association between insufficient GWG and the risk of SGA was greater in those aged ≥ 35 years (31-34 years: OR 2.08, 95% CI 1.19-3.55; ≥35 years: OR 2.65, 95% CI 1.47-4.74), while the impact of excessive GWG on the risk of LGA was more pronounced in those aged 31-34 years (31-34 years: OR 2.18, 95% CI 1.68-2.88; ≥35 years: OR 1.71, 95% CI 1.30-2.25). CONCLUSIONS: The stronger associations between abnormal GWG and adverse birth weights were mainly observed in women aged 31-34 years, and more attention should be paid to this age group.

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.

Assessment of Sleep Quality in Spanish Twin Pregnancy: An Observational Single-Center Study.

Women with twin pregnancies experience greater sleep disturbance compared to women with singleton pregnancies. The aims of this study were to explore the sleep quality in women with twin pregnancies and to compare their sleep dimensions with coetaneous single pregnancies. This was an observational study in which women were enrolled at the end of pregnancy in the Obstetric Service of Hospital La Paz (Spain). The women were classified as single (n = 143) or twin pregnancy (n = 62). Pregnant women responded to the Pittsburgh Sleep Quality Index to evaluate sleep quality, latency, duration, efficiency, perturbance, use of medication, and daytime dysfunction. The higher the index, the greater the alteration of sleep quality. Without statistical differences, a poor sleep quality was higher in women with single (66.7%) than women with twin pregnancies (22.8%). The good sleeper slept 6.8 h/day in single pregnancy and 7.3 h/day in twin pregnancy. The sleep perturbation and dysfunctionality were higher in women with twin than single pregnancies. The use of medication to sleep was significantly lower in women with twin than single pregnancies. In women with twin pregnancy, the body weight gain during first trimester had a positive correlation with worse sleep quality and sleep perturbations. Twin pregnancy needed more than 7 h/day to have a high sleep quality, showing greater sleep perturbations and daytime dysfunction than single pregnancies. The control of gestational body weight can improve the sleep quality, disturbances, and duration in twin gestations. Sleep screening during pregnancy would be necessary to handle sleep issues and increase benefits in twin gestational outcomes.

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.

Exploring the relationship between sunlight exposure, psychological health, and gestational weight gain: a prospective observational study.

INTRODUCTION: Gestational weight gain (GWG) is influenced by various factors during pregnancy. This study attempts to explore the relationship between environmental factors i.e., sunlight exposure and psychological health i.e. psychological well-being and sleep quality during pregnancy with total gestational weight gain. METHODS: This was a prospective observational study conducted in government maternity clinics in Kuala Lumpur. Pregnant women aged 19-39 years without comorbidities were recruited during second trimester and followed up until birth. The participants were required to wear a UVB dosimeter for a total of three consecutive days (2 weekdays and 1 weekend) to determine sunlight exposure (SED) during their second trimester. The PSQI and DASS-21 were used to determine sleep quality and psychological wellbeing, respectively. GWG data were collected from clinic health records. The association of sun exposure and psychological health with total GWG was determined using multiple linear regression. RESULTS: A total of 73 pregnant women aged 27.9 ± 3.3 years were included in the analysis. The prevalence of pregnant women exhibiting stress, anxiety, and depression symptoms was 11%, 40%, and 16% respectively. The global PSQI median score was 5 (IQR = 3), with 59% having poor sleep quality. Median sleep duration was 7 h (IQR = 2) while median sleep efficiency was 92% (IQR = 14). The median SED was 0.04 (IQR = 0.09), with 51% of them being under the 50th percentile. The majority had adequate GWG (58%). Sleep parameters were not found to be correlated with total GWG except for sleep latency (ρ = -0.356, p = 0.002). Sunlight exposure was found to have no significant relationship with sleep and total GWG. Adjusted multiple linear regression showed that greater depression is associated with higher total GWG (ß = 0.239, p = 0.039) while controlling for sleep quality. CONCLUSION: Depression was associated with total GWG when sleep quality was controlled for while sunlight exposure had no significant association with GWG. Future studies should study the complex relationship between factors of mental health, sleep, and weight gain during pregnancy. Healthcare providers may be better equipped to develop interventions aimed to prevent negative maternal and fetal health outcomes.

Pregnancy health in a multi-state U.S. population of systemically underserved patients and their children: PROMISE cohort design and baseline characteristics.

BACKGROUND: Gestational weight gain (GWG) is a routinely monitored aspect of pregnancy health, yet critical gaps remain about optimal GWG in pregnant people from socially marginalized groups, or with pre-pregnancy body mass index (BMI) in the lower or upper extremes. The PROMISE study aims to determine overall and trimester-specific GWG associated with the lowest risk of adverse birth outcomes and detrimental infant and child growth in these underrepresented subgroups. This paper presents methods used to construct the PROMISE cohort using electronic health record data from a network of community-based healthcare organizations and characterize the cohort with respect to baseline characteristics, longitudinal data availability, and GWG. METHODS: We developed an algorithm to identify and date pregnancies based on outpatient clinical data for patients 15 years or older. The cohort included pregnancies delivered in 2005-2020 with gestational age between 20 weeks, 0 days and 42 weeks, 6 days; and with known height and adequate weight measures needed to examine GWG patterns. We linked offspring data from birth records and clinical records. We defined study variables with attention to timing relative to pregnancy and clinical data collection processes. Descriptive analyses characterize the sociodemographic, baseline, and longitudinal data characteristics of the cohort, overall and within BMI categories. RESULTS: The cohort includes 77,599 pregnancies: 53% had incomes below the federal poverty level, 82% had public insurance, and the largest race and ethnicity groups were Hispanic (56%), non-Hispanic White (23%) and non-Hispanic Black (12%). Pre-pregnancy BMI groups included 2% underweight, 34% normal weight, 31% overweight, and 19%, 8%, and 5% Class I, II, and III obesity. Longitudinal data enable the calculation of trimester-specific GWG; e.g., a median of 2, 4, and 6 valid weight measures were available in the first, second, and third trimesters, respectively. Weekly rate of GWG was 0.00, 0.46, and 0.51 kg per week in the first, second, and third trimesters; differences in GWG between BMI groups were greatest in the second trimester. CONCLUSIONS: The PROMISE cohort enables characterization of GWG patterns and estimation of effects on child growth in underrepresented subgroups, ultimately improving the representativeness of GWG evidence and corresponding guidelines.

Maternal weight, smoking, and diabetes provided early predictors of longitudinal body mass index growth patterns in childhood.

AIM: The aim of this study was to identify factors affecting overweight growth development using extended body mass index (BMI) data combined with birth and maternal records from Finnish national registries. METHODS: The longitudinal data consist of growth measurements of 7372 from six birth cohorts in Finland: 1974 (n = 1109), 1981 (n = 983), 1991 (n = 607), 1994-1995 (n = 829), 2001 (n = 821), and 2003-2004 (n = 3023). Anthropometric data were collected from birth to age 15 years from the health records. Pregnancy health data were included for the four most recent birth cohorts (n = 2810). A statistical method called trajectory analysis was used to identify different BMI development trajectories. Factors associated with abnormal growth tracks were analysed using logistic regression models. RESULTS: High pre-pregnancy BMI, gestational diabetes mellitus, maternal smoking, and greater gestational weight gain than the Institute of Medicine (United States) recommendations were associated with the overweight growth track. Two of the trajectories didn't seem to follow the normal growth pattern: overweight growth track appeared to lead to overweight, while low birth BMI track showed accelerating growth after the adiposity rebound point of BMI growth. CONCLUSION: These findings suggest that maternal overweight before pregnancy, excessive gestational weight gain, gestational diabetes mellitus, and smoking could potentially be associated with the risk of obesity in children.

Relation of preconception eating behaviours to dietary pattern trajectories and gestational weight gain from preconception to late pregnancy.

Studies examining preconception eating behaviours with longitudinal dietary patterns from preconception to late pregnancy as well as gestational weight gain (GWG) are limited. We derived dietary pattern trajectories from preconception to late-pregnancy, and related preconception eating behaviours to these trajectories and GWG. Preconception eating behaviours were assessed using the Three-Factor Eating Questionnaire measuring cognitive restraint (CR) - conscious restriction of food intake, emotional eating (EE) - overeating in response to negative emotions, and uncontrolled eating (UE) - overeating with a feeling of lack of control. Dietary intakes were measured at preconception, 20-21 and 34-36 weeks' gestation with food frequency questionnaires. Dietary patterns were determined using factor analysis, and trajectories derived using group-based trajectory modelling. Inadequate and excessive GWG were defined according to Institute of Medicine guidelines based on weights at preconception and the last antenatal visit (median: 38 weeks' gestation). Two dietary patterns were derived: 'Fast Food, Fried Snacks and Desserts (FFD)' and 'Soup, Fish and Vegetables (SFV)'. Adherence trajectories from preconception to late-pregnancy were characterised as consistently high ("stable-high") and low ("stable-low"). Women with higher UE scores had higher odds of being in the "stable-high" trajectory (n = 34) of the FFD pattern [Odds Ratio (OR): 1.25, 95% Confidence Interval (CI): 1.03, 1.51], compared to "stable-low" (n = 260). Percentages of women with inadequate, adequate or excessive GWG were 21.7% (n = 70), 25.8% (n = 83), and 52.5% (n = 169), respectively; women with higher EE scores had a higher likelihood of excessive GWG [Relative Risk Ratio (RRR): 1.35, 95% CI: 1.02, 1.80], but this association was attenuated after adjusting for preconception body mass index. Eating behaviour interventions to improve dietary patterns among pregnant women may need to start as early as preconception, incorporating strategies to manage UE.

Associations Between Gestational Weight Gain, Gestational Diabetes, and Childhood Obesity Incidence.

INTRODUCTION: Excessive maternal gestational weight gain (GWG) is strongly correlated with childhood obesity, yet how excess maternal weight gain and gestational diabetes mellitus (GDM) interact to affect early childhood obesity is poorly understood. The purpose of this study was to investigate whether overall and trimester-specific maternal GWG and GDM were associated with obesity in offspring by age 6 years. METHODS: A cohort of 10,335 maternal-child dyads was established from electronic health records. Maternal weights at conception and delivery were estimated from weight trajectory fits using functional principal components analysis. Kaplan-Meier curves and Cox regression, together with generalized raking, examined time-to-childhood-obesity. RESULTS: Obesity diagnosed prior to age 6 years was estimated at 19.7% (95% CI: 18.3, 21.1). Maternal weight gain during pregnancy was a strong predictor of early childhood obesity (p < 0.0001). The occurrence of early childhood obesity was lower among mothers with GDM compared with those without diabetes (adjusted hazard ratio = 0.58, p = 0.014). There was no interaction between maternal weight gain and GDM (p = 0.55). Higher weight gain during the first trimester was associated with lower risk of early childhood obesity (p = 0.0002) whereas higher weight gain during the second and third trimesters was associated with higher risk (p < 0.0001). DISCUSSION: Results indicated total and trimester-specific maternal weight gain was a strong predictor of early childhood obesity, though obesity risk by age 6 was lower for children of mothers with GDM. Additional research is needed to elucidate underlying mechanisms directly related to trimester-specific weight gain and GDM that impede or protect against obesity prevalence during early childhood.

Excessive maternal gestational weight gain (GWG) and gestational diabetes mellitus (GDM) have been linked to childhood obesity. Yet, research on how excessive total and trimester-specific GWG and GDM interact to affect early childhood obesity remains inconclusive. This study found that inadequate weight gain in the first trimester and excessive weight gain in the second and third trimester were associated with higher risks of childhood obesity by age 6. No significant interaction between maternal GWG and GDM was noted suggesting that these two important maternal conditions do not have a combined effect on the risk of early childhood obesity.