Maternal pre-pregnancy body mass index, gestational weight gain trajectory, and risk of adverse perinatal outcomes

Effects of an mHealth intervention on maternal and infant outcomes from pregnancy to early postpartum for women with overweight or obesity: A randomized controlled trial

BACKGROUND

Women with overweight (OW) and those with obesity (OB) tend to gain excessive weight during pregnancy, often resulting in adverse outcomes. The long-term effects of mobile health (mHealth) interventions on maternal and infant outcomes remain unclear.

AIMS

To examine the effects of an mHealth intervention on OW and OB from the course of their pregnancy to six months postpartum.

METHODS

A randomized controlled trial was conducted in northern Taiwan. Ninety-two pregnant women with a body mass index (BMI)of ≥25 kg/m2 were recruited from prenatal clinics at <17 weeks of gestation. Prepregnancy weight was baseline maternal weight, with data collected subsequently at the last assessment before childbirth and six months postpartum. The intervention group (IG) received the mHealth intervention, while the control group (CG) received standard antenatal care. The trial was registered on ClinicalTrials.gov (identifier: NCT04553731) with the initial registration date of September 16, 2020.

FINDINGS

The IG tended to have a lower mean body weight than the CG at the last assessment before childbirth (82.23 kg vs 84.35 kg) and at six months postpartum (72.55 Kg vs 72.58 Kg). IG's newborn birth weight was significantly lower than CG's (3074.8 vs. 3313.6 g; p = 0.009). Regression analysis revealed that OB in IG had a significant reduction in weight before childbirth (β = -7.51, p = 0.005) compared to OB in CG. Compared to OW in CG, both OW in IG (β = -243.59, p = 0.027) and OB in IG (β = -324.59, p = 0.049) were associated with decreased newborn birth weight.

CONCLUSIONS

mHealth helped women with obesity to successfully manage their GWG and body weight before childbirth and newborns' birth weight, despite this effect not persisting to reduce weight retention at six months postpartum.

Exposure to PM2.5 and Its Constituents in Relation to Thyroid Function of Pregnant Women: Separate and Mixture Analyses

The relationships between exposure to PM2.5 and its constituents and thyroid hormone (TH) levels in pregnant women are still uncertain, particularly regarding the impact of mixed exposure to PM2.5 constituents on thyroid function during pregnancy. This study aimed to investigate the individual and mixed effects of PM2.5 and its constituents on TH levels during pregnancy. Fluorescence and chemiluminescence immunoassays were utilized to measure serum concentrations of free thyroxine (FT4) and thyroid-stimulating hormone (TSH) in pregnant women participating in the Fujian Birth Cohort Study (FJBCS). PM2.5 and its constituents were obtained from the ChinaHighAirPollutants dataset. Generalized linear regression model and mixture analysis were applied to explore the individual and mixed effects of PM2.5 and its constituents on TH levels. 13711 participants from the FJBCS were taken into the final analysis. In the context of separate exposure, an increase of one interquartile range (IQR) in PM2.5 exposure during the 1st trimester, 2nd trimester, and entire pregnancy was associated with a decrease of -0.042 (-0.050, -0.034), -0.017 (-0.026, -0.009), and -0.011 (-0.017, -0.004) in FT4 levels, respectively. As well, significant negative associations were observed between FT4 levels and PM2.5 constituents. Additionally, PM2.5 and its constituents were in relation to an increased risk of hypothyroxinemia in pregnant women. It is noteworthy that, in the context of mixed exposure, the weighted quantile sum regression (WQS) indices were significantly associated with both FT4 levels (1st trimester: -0.031 (-0.036, -0.026); 2nd trimester: -0.026 (-0.030, -0.023); whole pregnancy: -0.024 (-0.028, -0.020)) and hypothyroxinemia risk (1st trimester: 1.552 (1.312, 1.821); 2nd trimester: 1.453 (1.194, 1.691); whole pregnancy: 1.402 (1.152, 1.713)). PM2.5 and its chemical constituents may affect thyroid function in pregnant women individually and in combination, with the effects observed during early gestational exposure being most pronounced.

Gestational weight gain trajectories in patients with gestational diabetes mellitus: a retrospective cohort study

Aims/Background Gestational diabetes mellitus is a common pregnancy complication that affects approximately 14% of pregnancies worldwide and can lead to adverse maternal and neonatal outcomes. This study aimed to investigate the trajectories of gestational weight gain among gestational diabetes mellitus patients and to inform the development of effective weight management strategies. Methods Demographic and antenatal examination data from 1421 pregnant women diagnosed with gestational diabetes mellitus were retrospectively analysed. Quantitative data comparisons were performed using Chi-square tests, Fisher's exact test, t-tests, and one-way analysis of variance. Group-based trajectory modelling was employed to identify the trajectories of gestational weight gain among patients with gestational diabetes mellitus. Results This study revealed that pre-pregnancy body mass index and types of gestational diabetes mellitus significantly influence gestational weight gain (p < 0.05). Group-based trajectory modelling identified three distinct gestational weight gain trajectories. Patients with gestational diabetes mellitus demonstrated a continuous weight gain throughout pregnancy, while women who were overweight or obese before pregnancy were more likely to follow a low-speed growth trajectory. Women in the rapid growth trajectory group were more inclined to deliver by caesarean section and were more likely to give birth to macrosomic infants. Conclusion Our research underscores the importance of identifying and distinguishing between different gestational weight gain trajectories in pregnant women, thereby identifying high-risk groups, which is crucial for improving the health conditions of both mothers and newborns.

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.

Associations between gestational weight gain and weight development of the offspring: Differences depending on maternal pre-pregnancy BMI

PURPOSE

Obesity rates are rising, and the gestational weight gain (GWG) of most women does not comply with current guidelines. This study assesses the association of pre-pregnancy BMI (ppBMI) and GWG with the child's weight development and investigates whether associations with GWG differ depending on ppBMI.

METHODS

Data were obtained from the cohort study LIFE Child (Germany), comprising 691 mother-child pairs. Children's weight was followed until age five. Associations between maternal ppBMI, GWG, and children's weight were evaluated using regression analyses.

RESULTS

The association between GWG and birth weight (BW) was significantly positive in normal and underweight (n/u) women (βGWG = 0.05, p < 0.01, 95% confidence interval (CI) 0.03-0.07), but not in women with overweight or obesity (o/o) (βGWG = 0.0002, p = 0.99, 95% CI -0.03 to 0.03). The risk of giving birth to an infant who was large for gestational age (LGA) increased with rising GWG in n/u women (OR = 1.6, p < 0.01, 95% CI 1.23-2.25). Women with o/o were at increased risk for a LGA baby regardless of GWG (OR = 3, p < 0.01, 95% CI 1.34-6.97). This trend persisted in the child's weight development during the first 5 years of life.

CONCLUSION

Women with o/o might increase their offspring's risk for higher weight at birth and in early childhood. In n/u women, GWG might be the more influential factor. Women should strive for normal weight before conception and should be more attentive to GWG.

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.

Association of prepregnancy body mass index and gestational weight gain trajectory with adverse pregnancy outcomes-a prospective cohort study in Shanghai

OBJECTIVES

The objective was to investigate the associations of maternal prepregnancy body mass index (BMI) and gestational weight gain (GWG) trajectories with adverse pregnancy outcomes (APOs).

DESIGN

This was a prospective cohort study.

SETTING

This study was conducted in Shanghai Pudong New Area Health Care Hospital for Women and Children, Shanghai, China.

PRIMARY AND SECONDARY OUTCOME MEASURES

A cohort study involving a total of 2174 pregnant women was conducted. Each participant was followed to record weekly weight gain and pregnancy outcomes. The Institute of Medicine classification was used to categorise prepregnancy BMI, and four GWG trajectories were identified using a latent class growth model.

RESULTS

The adjusted ORs for the risks of large for gestational age (LGA), macrosomia, gestational diabetes mellitus (GDM) and hypertensive disorders of pregnancy (HDP) were significantly greater for women with prepregnancy overweight/obesity (OR=1.77, 2.13, 1.95 and 4.24; 95% CI 1.3 to 2.42, 1.32 to 3.46, 1.43 to 2.66 and 2.01 to 8.93, respectively) and lower for those who were underweight than for those with normal weight (excluding HDP) (OR=0.35, 0.27 and 0.59; 95% CI 0.22 to 0.53, 0.11 to 0.66 and 0.36 to 0.89, respectively). The risk of small for gestational age (SGA) and low birth weight (LBW) was significantly increased in the underweight group (OR=3.11, 2.20; 95% CI 1.63 to 5.92, 1.10 to 4.41; respectively) compared with the normal-weight group; however, the risk did not decrease in the overweight/obese group (p=0.942, 0.697, respectively). GWG was divided into four trajectories, accounting for 16.6%, 41.4%, 31.7% and 10.3% of the participants, respectively. After adjustment for confounding factors, the risk of LGA was 1.54 times greater for women in the slow GWG trajectory group than for those in the extremely slow GWG trajectory group (95% CI 1.07 to 2.21); the risk of SGA and LBW was 0.37 times and 0.46 times lower for women in the moderate GWG trajectory group and 0.14 times and 0.15 times lower for women in the rapid GWG trajectory group, respectively; the risk of macrosomia and LGA was 2.65 times and 2.70 times greater for women in the moderate GWG trajectory group and 3.53 times and 4.36 times greater for women in the rapid GWG trajectory group, respectively; and the women in the other three trajectory groups had a lower risk of GDM than did those in the extremely slow GWG trajectory group, but there was not much variation in the ORs. Notably, different GWG trajectories did not affect the risk of HDP.

CONCLUSIONS

As independent risk factors, excessively high and low prepregnancy BMI and GWG can increase the risk of APOs.

The adverse impact of maternal ozone exposure on fetal growth in utero and the interaction with residential greenness

This study aimed to investigate the effect of maternal ozone exposure on fetal growth during pregnancy, as well as the combined effect and interaction of ozone and residential greenness. We included a total of 14990 singleton pregnancies from the Fujian Birth Cohort Study. During pregnancy, fetal growth parameters including estimated fetal weight (EFW), femur length (FL), head circumference (HC), and abdominal circumference (AC). To investigate the associations between ozone exposure and the above-mentioned outcomes, generalized estimating equation approach and generalized linear regression were used, as appropriate. In the adjusted models, we observed that the Z scores of EFW (-0.031 (-0.048, -0.014)), FL (-0.021 (-0.038, -0.004)), and AC (-0.025 (-0.042, -0.007)) decreased with per interquartile range (IQR) increase of ozone concentration. Compared to participants with low ozone exposure and high NDVI, those with high ozone exposure and low NDVI experienced the largest decrease in Z scores for EFW (-0.049 (-0.079, -0.02)), FL (-0.034 (-0.063, -0.004)), HC (-0.034 (-0.065, -0.004)), and AC (-0.041 (-0.072, -0.01)), respectively. Interestingly, we discovered the effect modification of NDVI on the relationship between ozone exposure and fetal growth restriction (P for interaction < 0.05). This study established a negative relationship of maternal ozone exposure and fetal growth. Of importance, this study discovered the joint effect and interaction between ozone and residential greenness exposure.

Pre-pregnancy body mass index and glycated-hemoglobin with the risk of metabolic diseases in gestational diabetes: a prospective cohort study

Background

Metabolic diseases during pregnancy result in negative consequences for mothers. Pre-pregnancy body mass index (BMI) and late-pregnancy glycated-hemoglobin (HbA1c) are most important factors independently affecting the risk of gestational diabetes mellitus (GDM). However how both affect the combined risk of other metabolic diseases in women with GDM is unclear. The study aims to investigate the influence of pre-pregnancy BMI and pregnancy glycemic levels on other gestational metabolic diseases in women with GDM.

Methods

Pregnancies with GDM from January 2015 to December 2018 in the Xi'an longitudinal mother-child cohort study (XAMC) were retrospectively enrolled. Those without other metabolic diseases by the time of oral glucose tolerance test (OGTT) detection were finally recruited and divided into four groups by pre-pregnancy BMI (Underweight <18.5kg/m2; Normal weight 18.5-23.9 kg/m2; Overweight 24.0-27.9 kg/m2; Obesity ≥28.0 kg/m2, respectively) or two groups by HbA1c in late pregnancy (normal HbA1c<5.7%; high HbA1c≥5.7%). Multivariate logistic regression analysis was used to identify risk factors. Interaction between pre-pregnancy BMI (reference group 18.5-23.9 kg/m2) and HbA1c (reference group <5.7%) was determined using strata-specific analysis.

Results

A total of 8928 subjects with GDM were included, 16.2% of which had a composite of metabolic diseases. The pre-pregnancy overweight and obesity, compared with normal BMI, were linked to the elevated risk of the composite of metabolic diseases, particularly pre-eclampsia (both P <0.001) and gestational hypertension (both P <0.001). Meanwhile, patients with high HbA1c had an obvious higher risk of pre-eclampsia (P< 0.001) and gestational hypertension (P= 0.005) compared to those with normal HbA1c. In addition, there were significant interactions between pre-pregnancy BMI and HbA1c (P< 0.001). The OR of pre-pregnancy BMI≥ 28 kg/m2 and HbA1c≥ 5.7% was 4.46 (95% CI: 2.85, 6.99; P< 0.001). The risk of other metabolic diseases, except for pre-eclampsia (P= 0.003), was comparable between the two groups of patients with different HbA1c levels at normal pre-pregnancy BMI group. However, that was remarkably elevated in obese patients (P= 0.004), particularly the risk of gestational hypertension (P= 0.004).

Conclusion

Pre-pregnancy overweight/obesity and late-pregnancy high HbA1c increased the risk of other gestational metabolic diseases of women with GDM. Monitoring and controlling late-pregnancy HbA1c was effective in reducing metabolic diseases, particularly in those who were overweight/obese before conception.

Effectiveness of a nurse-led mHealth app to prevent excessive gestational weight gain among overweight and obese women: A randomized controlled trial

OBJECTIVE

To explore the effectiveness of a nurse-led mobile health (mHealth) intervention to prevent excessive gestational weight gain (GWG) in overweight and obese women.

METHODS

A randomized controlled trial with an experimental study design. Ninety-two pregnant women with body mass index (BMI) ≥25 kg/m² at less than 17 weeks gestation were recruited from two prenatal clinics in northern Taiwan from January to June 2020. The experimental group used the MyHealthyWeight (MHW) app and a wearable activity tracker (WAT), and the controls received standard antenatal treatments with no mHealth-based elements. Two hospital follow-up visits were scheduled at 24-26 weeks in the second trimester and 34-36 weeks in the third trimester. A generalized estimating equation (GEE) was used to examine the trajectories and the effectiveness of mHealth on GWG.

RESULTS

No difference in GWG was found between the intervention and control groups at baseline (p > 0.05). The GWG trajectory in the entire cohort of women with obesity exhibited a quadratic pattern (ß = 1.8, 95% confidence interval [CI] = 1.27-2.32), and intervention participants' weekly GWG was gained significantly lower than their controls in the second trimester (p < 0.05). Throughout the pregnancy, the mHealth intervention group had a significantly lower proportion of individuals who exceeded their GWG in both total (21.6% vs. 32.6%) and weekly weight gain (first trimester = 58.7% vs. 65.2%; second trimester = 45% vs. 67.4%; third trimester = 48.6% vs. 55.1%). In particular, among obese women in the third trimester, those in the intervention group gained less gestational weight than their controls. The adjusted body weight difference was 5.44 kg (p = 0.023), signifying the total GWG difference (3.30 vs. 8.74 kg) between the means of the two groups. The GEE model indicated that obese women who were aged 35 years, had prepregnancy exercise habits, perceived self-efficacy of diet, and more physical activity tended to have low GWG (p < 0.05).

CONCLUSIONS

The nurse-led mHealth-based intervention shows promising results in significantly preventing excessive GWG among high-BMI women. More effectiveness was found among the obese subgroup.

CLINICAL RELEVANCE

The mHealth-based intervention would be successfully implemented by nurses to help high-BMI women maintain their optimal body weight and promote healthy behavioral changes, particularly in diet and physical activity during pregnancy.