Optimizing healthy gestational weight gain in women at high risk of gestational diabetes: a randomized controlled trial

Investigating discrepancies in findings between rigorous randomized trials and meta-analyses evaluating pregnancy interventions to limit gestational weight gain

INTRODUCTION

Robust randomized trials consistently demonstrate little impact from diet and physical activity interventions on gestational weight gain (GWG) and clinical outcomes, although meta-analyses report some benefit. Our aim was to evaluate the effect of trial quality on treatment effect estimates and review conclusions.

METHODS

We conducted a systematic review of dietary and/or physical activity interventions for pregnant women with a body mass index ≥18.5 kg/m2. We assessed studies for risk of bias and methodological features impacting reliability. Outcomes included GWG; gestational diabetes mellitus (GDM); pre-eclampsia; caesarean birth; and birth weight measures. For each outcome, a sequence of meta-analyses was performed based on intervention group and level of potential bias in the effect estimate.

RESULTS

We identified 128 eligible studies. The most robust estimate from a combined diet and physical activity behavioral intervention, with only studies at negligible risk of bias, was a difference in GWG of 1.10 kg (95% CI -1.62 to -0.58; 17,755 women). There was no evidence of an effect on any clinical outcomes.

CONCLUSIONS

Our findings highlight discrepancies produced by the indiscriminate inclusion of studies with methodological flaws in previous systematic reviews. Regular weighing of pregnant women is futile in the absence of clinical benefit.

Gestational Metabolic Risk: A Narrative Review of Pregnancy-Related Complications and of the Effectiveness of Dietary, Exercise and Lifestyle Interventions during Pregnancy on Reducing Gestational Weight Gain and Preventing Gestational Diabetes Mellitus

Objective: This study is a Narrative Review that aims at investigating the implications of obesity, excessive gestational weight gain (GWG) and gestational diabetes mellitus (GDM). Additionally, this Review seeks to explore the effectiveness of nutrition, and/or exercise interventions during pregnancy on reducing GWG and preventing GDM. Materials and Methods: The search in literature included studies that identified obesity, GWG, GDM and associated risks during pregnancy. Also, SR and MA focusing on interventions including diet, or physical activity (PA), or combined (i.e., lifestyle interventions) and their impact on metabolic risk during pregnancy, were identified through searches in PubMed, Cochrane Database of Systematic Reviews (CDSRs), and Scopus. Results: The study findings suggest that lifestyle interventions during pregnancy may be effective in reducing excessive GWG. Regarding the prevention of GDM, results from studies evaluating lifestyle interventions vary. However, significant and less controversial results were reported from studies assessing the efficacy of exercise interventions, particularly in high-risk pregnant women. Conclusions: Lifestyle interventions during pregnancy may reduce excessive GWG. Exercise during pregnancy may prevent GDM, especially in high-risk pregnant women. Future research is warranted to tailor lifestyle interventions for optimal effectiveness 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.

Effective interventions in preventing gestational diabetes mellitus: A systematic review and meta-analysis

BACKGROUND

Lifestyle choices, metformin, and dietary supplements may prevent GDM, but the effect of intervention characteristics has not been identified. This review evaluated intervention characteristics to inform the implementation of GDM prevention interventions.

METHODS

Ovid, MEDLINE/PubMed, and EMBASE databases were searched. The Template for Intervention Description and Replication (TIDieR) framework was used to examine intervention characteristics (who, what, when, where, and how). Subgroup analysis was performed by intervention characteristics.

RESULTS

116 studies involving 40,940 participants are included. Group-based physical activity interventions (RR 0.66; 95% CI 0.46, 0.95) reduce the incidence of GDM compared with individual or mixed (individual and group) delivery format (subgroup p-value = 0.04). Physical activity interventions delivered at healthcare facilities reduce the risk of GDM (RR 0.59; 95% CI 0.49, 0.72) compared with home-based interventions (subgroup p-value = 0.03). No other intervention characteristics impact the effectiveness of all other interventions.

CONCLUSIONS

Dietary, physical activity, diet plus physical activity, metformin, and myoinositol interventions reduce the incidence of GDM compared with control interventions. Group and healthcare facility-based physical activity interventions show better effectiveness in preventing GDM than individual and community-based interventions. Other intervention characteristics (e.g. utilization of e-health) don't impact the effectiveness of lifestyle interventions, and thus, interventions may require consideration of the local context.

Mapping Lifestyle Interventions for Gestational Diabetes Prevention: A Scoping Review

PURPOSE OF REVIEW

The purpose of this study was to conduct a scoping review to map intervention, sample, and physiologic measurement characteristics of lifestyle interventions for gestational diabetes mellitus (GDM) prevention.

RECENT FINDINGS

A total of 19 studies met selection criteria from 405 articles screened (PubMed, Web of Science). No studies were US-based (47% multi-site), and all were delivered in clinical settings. The most targeted nutrition components were low carbohydrate intake (sugar rich foods/added sugars, low glycemic index), low fat intake (mainly low-fat meat, dairy, and saturated fat), and increased fruits and vegetables. Many studies promoted 150 min/week moderate-intensity physical activity. Only two studies provided supervised physical activity sessions. Dietitians and nurses were the most common implementers. Samples were characterized as adults with obesity (mean age 31 yr, BMI 31 kg/m2). Asian populations were predominantly studied. Four studies used theoretical frameworks (75% of which used Social Cognitive Theory). GDM diagnostic criteria set forth by the American Diabetes Association were the most widely used. Insulin sensitivity was commonly assessed via fasting indices. There was a lack of multi-disciplinary, multi-level, and theory-based lifestyle interventions for reducing GDM risk. Addressing these gaps and prioritizing high-risk populations in the US with measurement of traditional and novel biomarkers will advance the field.

Interventions in preconception and pregnant women at risk of gestational diabetes; a systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Women at risk of gestational diabetes mellitus (GDM) need preventative interventions.

OBJECTIVE

To evaluate targeted interventions before and during pregnancy for women identified as being at risk of developing GDM.

METHODS

Systematic review and meta-analysis conducted following PRISMA guidelines. MEDLINE, EMBASE and the Cochrane Library in addition to reference and citation lists were searched to identify eligible randomised controlled trials (RCTs) utilising risk stratification during the preconception period or in the first/early second trimester. Screening and data extraction were carried out by the authors independently. Quality assessment was conducted based on the Cochrane risk-of-bias tool. Random effects meta-analysis and narrative synthesis were performed.

RESULTS

Eighty-four RCTs were included: two during preconception and 82 in pregnancy, with a pooled sample of 22,568 women. Interventions were behavioural (n = 54), dietary supplementation (n = 19) and pharmacological (n = 11). Predictive factors for risk assessment varied; only one study utilised a validated prediction model. Gestational diabetes was reduced in diet and physical activity interventions (risk difference - 0.03, 95% CI 0.06, - 0.01; I2 58.69%), inositol (risk difference - 0.19, 95% CI 0.33, - 0.06; I2 92.19%), and vitamin D supplements (risk difference - 0.16, 95% CI 0.25, - 0.06; I2 32.27%). Subgroup analysis showed that diet and physical activity interventions were beneficial in women with ≥ 2 GDM risk factors (risk difference - 0.16, 95% CI 0.25, - 0.07; I2 11.23%) while inositol supplementation was effective in women with overweight or obesity (risk difference - 0.17, 95% CI 0.22, - 0.11; I2 0.01%). Effectiveness of all other interventions were not statistically significant.

CONCLUSIONS

This review provides evidence that interventions targeted at women at risk of GDM may be an effective strategy for prevention. Further studies using validated prediction tools or multiple risk factors to target high-risk women for intervention before and during pregnancy are warranted.

Temporal validation and updating of a prediction model for the diagnosis of gestational diabetes mellitus

OBJECTIVE

The original Monash gestational diabetes mellitus (GDM) risk prediction in early pregnancy model is internationally externally validated and clinically implemented. We temporally validate and update this model in a contemporary population with a universal screening context and revised diagnostic criteria and ethnicity categories, thereby improving model performance and generalizability.

STUDY DESIGN AND SETTING

The updating dataset comprised of routinely collected health data for singleton pregnancies delivered in Melbourne, Australia from 2016 to 2018. Model predictors included age, body mass index, ethnicity, diabetes family history, GDM history, and poor obstetric outcome history. Model updating methods were recalibration-in-the-large (Model A), intercept and slope re-estimation (Model B), and coefficient revision using logistic regression (Model C1, original ethnicity categories; Model C2, revised ethnicity categories). Analysis included 10-fold cross-validation, assessment of performance measures (c-statistic, calibration-in-the-large, calibration slope, and expected-observed ratio), and a closed-loop testing procedure to compare models' log-likelihood and akaike information criterion scores.

RESULTS

In 26,474 singleton pregnancies (4,756, 18% with GDM), the original model demonstrated reasonable temporal validation (c-statistic = 0.698) but suboptimal calibration (expected-observed ratio = 0.485). Updated model C2 was preferred, with a high c-statistic (0.732) and significantly better performance in closed testing.

CONCLUSION

We demonstrated updating methods to sustain predictive performance in a contemporary population, highlighting the value and versatility of prediction models for guiding risk-stratified GDM care.

Effectiveness of Lifestyle Interventions during Pregnancy on Preventing Gestational Diabetes Mellitus in High-Risk Women: A Systematic Review and Meta-Analyses of Published RCTs

BACKGROUND

Until now, it is uncertain whether lifestyle interventions during pregnancy can prevent gestational diabetes mellites (GDM) in high-risk pregnant women.

OBJECTIVE

This study aims at investigating the effectiveness of dietary interventions and/or exercise interventions during pregnancy for preventing GDM in high-risk pregnant women.

MATERIALS AND METHODS

Eligible randomized controlled trials (RCTs) were selected after a search in CENTRAL, Scopus, and PubMed. Synthesis was performed for the outcome of GDM in women with any identified GDM risk factor. Separate meta-analyses (MA) were performed to assess the efficacy of either nutrition or physical activity (PA) interventions or both combined compared with standard prenatal care for preventing GDM. Subgroup and sensitivity analyses, as well as meta-regressions against OR, were performed to assess potentional heterogeneity. Overall quality, the quality of RCTs, and publication bias were also evaluated.

RESULTS

A total of 13,524 participants comprising high-risk pregnant women in 41 eligible RCTs were analyzed for GDM. Women receiving only a nutrition intervention during pregnancy were less likely to experience GDM compared with women following standard prenatal care. Among 3109 high-risk pregnant women undergoing only dietary intervention for preventing GDM, 553 (17.8%) developed GDM; however, the result of the MA was marginally not significant (OR 0.73, 95%CI 0.51, 1.03; p-value 0.07), (Q 21.29, p-value 0.01; I2 58% (95%CI 10, 78%)). Subgroup analyses demonstrated an effect for studies that were conducted in Great Britain (OR 0.65, 95%CI 0.49, 0.81; p-value 0.003), and in Spain (OR 0.50, 95%CI 0.27, 0.94; p-value 0.03), for studies with forms of the Mediterranean diet as the intervention's component (OR 0.61; 95%CI 0.46, 0.81; p-value 0.0005), and for studies including a motivation arm in the intervention (OR 0.71, 95%CI 0.58, 0.87; p-value 0.0008). Among 2742 high-risk pregnant women being analyzed for GDM outcome after receiving only an exercise intervention, 461 (16.8%) were diagnosed with GDM. Women after receiving PA intervention were less likely to develop GDM (OR 0.64, 95%CI 0.51, 0.80; p-value < 0.0001), (Q 11.27, p-value 0.51; I2 0% (95%CI 0, 99%)). Finally, 1308 (17%) cases of GDM were diagnosed among 7673 high-risk pregnant women undergoing both diet and PA intervention. Women in the group of mixed lifestyle intervention had a significant reduction in incidence of GDM (OR 0.70, 95%CI 0.55, 0.90; p-value 0.005), (Q 50.32, p-value < 0.0001, I2 66%, (95% CI 44, 79%)).

CONCLUSIONS

The results of this study support the efficacy of lifestyle interventions during pregnancy for preventing GDM in high-risk women if an exercise component is included in the intervention arm, either alone, or combined with diet. A combined lifestyle intervention including physical exercise and a Mediterranean diet accompanied by motivation support may be considered the most effective way to prevent GDM among high-risk women during pregnancy. Future research is needed to strengthen these findings.

Key Components of Antenatal Lifestyle Interventions to Optimize Gestational Weight Gain: Secondary Analysis of a Systematic Review

Importance

Randomized clinical trials have found that antenatal lifestyle interventions optimize gestational weight gain (GWG) and pregnancy outcomes. However, key components of successful interventions for implementation have not been systematically identified.

Objective

To evaluate intervention components using the Template for Intervention Description and Replication (TIDieR) framework to inform implementation of antenatal lifestyle interventions in routine antenatal care.

Data Sources

Included studies were drawn from a recently published systematic review on the efficacy of antenatal lifestyle interventions for optimizing GWG. The Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, Health Technology Assessment Database, MEDLINE, and Embase were searched from January 1990 to May 2020.

Study Selection

Randomized clinical trials examining efficacy of antenatal lifestyle interventions in optimizing GWG were included.

Data Extraction and Synthesis

Random effects meta-analyses were used to evaluate the association of intervention characteristics with efficacy of antenatal lifestyle interventions in optimizing GWG. The results are reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline. Data extraction was performed by 2 independent reviewers.

Main Outcomes and Measures

The main outcome was mean GWG. Measures included characteristics of antenatal lifestyle interventions comprising domains related to theoretical framework, material, procedure, facilitator (allied health staff, medical staff, or researcher), delivery format (individual or group), mode, location, gestational age at commencement (<20 wk or ≥20 wk), number of sessions (low [1-5 sessions], moderate [6-20 sessions], and high [≥21 sessions]), duration (low [1-12 wk], moderate [13-20 wk], and high [≥21 wk]), tailoring, attrition, and adherence. For all mean differences (MDs), the reference group was the control group (ie, usual care).

Results

Overall, 99 studies with 34 546 pregnant individuals were included with differential effective intervention components found according to intervention type. Broadly, interventions delivered by an allied health professional were associated with a greater decrease in GWG compared with those delivered by other facilitators (MD, -1.36 kg; 95% CI, -1.71 to -1.02 kg; P < .001). Compared with corresponding subgroups, dietary interventions with an individual delivery format (MD, -3.91 kg; 95% CI -5.82 to -2.01 kg; P = .002) and moderate number of sessions (MD, -4.35 kg; 95% CI -5.80 to -2.89 kg; P < .001) were associated with the greatest decrease in GWG. Physical activity and mixed behavioral interventions had attenuated associations with GWG. These interventions may benefit from an earlier commencement and a longer duration for more effective optimization of GWG.

Conclusions and Relevance

These findings suggest that pragmatic research may be needed to test and evaluate effective intervention components to inform implementation of interventions in routine antenatal care for broad public health benefit.

The effect of motivational interviewing and/or cognitive behaviour therapy techniques on gestational weight gain - a systematic review and meta-analysis

BACKGROUND

Women with gestational weight gain (GWG) that is below or above recommendations are at risk of adverse perinatal outcomes. Motivational interviewing and/or cognitive behaviour therapy have demonstrated efficacy in initiating and sustaining behaviour change, including weight control. The objective of this review was to investigate the effect of antenatal interventions that include components of motivational interviewing and/or cognitive behaviour therapy on gestational weight gain.

METHODS

This review was designed and reported in accordance with guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Five electronic databases were systematically searched to March 2022. Randomised controlled trials evaluating interventions with identified components of motivational interviewing and/or cognitive behaviour therapies were included. Pooled proportions of appropriate GWG and GWG above or below guidelines, and standardised mean difference for total gestational weight gain, were calculated. Risk of bias in included studies was evaluated using the Risk of Bias 2 tool, and the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach was used to evaluate the quality of evidence.

RESULTS

Twenty-one studies (8030 participants) were included. Overall, MI and/or CBT interventions had a small effect on the total gestational weight gain (SMD: -0.18, 95% confidence interval: -0.27 to -0.09, p < 0.001) and improved the proportion of women achieving recommended gestational weight gain (29% versus 23% in the comparison, p < 0.001). The GRADE assessment indicated that overall quality of evidence is very uncertain, however sensitivity analyses to account for high risk of bias produced similar results to original meta-analyses. The magnitude of effect was greater in women with overweight or obesity when compared to women with BMI < 25 kg/m².

CONCLUSION

Motivational interviewing and/or cognitive behaviour therapy techniques may be effective for promoting healthy gestational weight gain. Nevertheless, a high proportion of women do not achieve recommended gestational weight gain. Future interventions should consider factors, including clinician and consumer perspectives, in the design and delivery of psychosocial interventions that aim to support healthy gestational weight gain.

TRIAL REGISTRATION

The protocol for this review was registered with the PROSPERO International register of systematic reviews (registration number CRD42020156401).

Effects of prenatal exercise on gestational weight gain, obstetric and neonatal outcomes: FitMum randomized controlled trial

BACKGROUND

To investigate the effects of two different exercise interventions during pregnancy on gestational weight gain (GWG) and obstetric and neonatal outcomes compared to standard care. Additionally, we aimed to improve standardization of GWG measurements by developing a model to estimate GWG for a standardized pregnancy period of 40 weeks and 0 days accounting for individual differences in gestational age (GA) at delivery.

METHODS

In a randomized controlled trial we compared the effects of structured supervised exercise training (EXE) three times per week throughout pregnancy versus motivational counselling on physical activity (MOT) seven times during pregnancy with standard care (CON) on GWG and obstetric and neonatal outcomes. Uniquely, to estimate GWG for a standardized pregnancy period, we developed a novel model to predict GWG based on longitudinally observed body weights during pregnancy and at admission for delivery. Observed weights were fitted to a mixed effects model that was used to predict maternal body weight and estimate GWG at different gestational ages. Obstetric and neonatal outcomes, among them gestational diabetes mellitus (GDM) and birth weight, were obtained after delivery. GWG and the investigated obstetric and neonatal outcomes are secondary outcomes of the randomized controlled trial, which might be underpowered to detect intervention effects on these outcomes.

RESULTS

From 2018-2020, 219 healthy, inactive pregnant women with median pre-pregnancy BMI of 24.1 (21.8-28.7) kg/m² were included at median GA 12.9 (9.4-13.9) weeks and randomized to EXE (n = 87), MOT (n = 87) or CON (n = 45). In total 178 (81%) completed the study. GWG at GA 40 weeks and 0 days did not differ between groups (CON: 14.9 kg [95% CI, 13.6;16.1]; EXE: 15.7 kg [14.7;16.7]; MOT: 15.0 kg [13.6;16.4], p = 0.538), neither did obstetric nor neonatal outcomes. For example, there were no differences between groups in the proportions of participants developing GDM (CON: 6%, EXE: 7%, MOT: 7%, p = 1.000) or in birth weight (CON: 3630 (3024-3899), EXE: 3768 (3410-4069), MOT: 3665 (3266-3880), p = 0.083).

CONCLUSIONS

Neither structured supervised exercise training nor motivational counselling on physical activity during pregnancy affected GWG or obstetric and neonatal outcomes compared to standard care.

TRIAL REGISTRATION

ClinicalTrials.gov; NCT03679130; 20/09/2018.

The Role of Phytochemicals and Plant-Based Diets in Gestational Diabetes: Evidence from Clinical Trials

Gestational diabetes mellitus (GDM) is defined as glucose intolerance identified during pregnancy. The increased risk of pregnancy complications and the adverse health effects for the mother and baby associated with GDM require urgent and effective ways to control the condition. The primary goal of this semi-quantitative review was to examine the effects of phytochemicals and plant-based diets on GDM in clinical studies involving women undergoing pregnancy and to summarize the findings for application in clinical practice and disease management. The articles included in this review show that intervention strategies, including fruits, vegetables, whole grains, nuts and seeds, and tea, may be beneficial in the management of GDM and lower blood glucose and improve adverse pregnancy outcomes in these women. The randomized controlled trials reviewed collectively show improved glycemic control markers, blood lipid values, and body weight and composition when supplemented with phytochemical-rich supplements and foods compared to those in the control groups. The findings support the clinical observations of lower GDM risks in women consuming plant-derived diets rich in phytochemicals. Nutrition interventions involving plant-based foods and diets are thus a practical way to reduce hyperglycemia both in patients diagnosed with GDM and those at high risk for the development of GDM.

Effect of Gestational Weight Gain during the First Half of Pregnancy on the Incidence of GDM, Results from a Pregnant Cohort in Northern Greece

The aim of this study was to evaluate the effect of gestational weight gain (GWG) up to 23⁺⁶ weeks of gestation on the incidence of Gestational Diabetes Mellitus (GDM). A pregnant cohort of 5948 women in Northern Greece was recruited. Anthropometric features before and during pregnancy were recorded, the GWG by 23⁺⁶ weeks was calculated and a Generalized Linear Regression Model (GLM) with subgroup analyses based on weight status were computed. GDM was diagnosed in 5.5% of women. GLM results showed that GDM likelihood increased with maternal age (MA) and pre-pregnancy BMI (aOR: 1.08, 95%CI: [1.06, 1.11] and aOR: 1.09, 95%CI: [1.09, 1.11], respectively). Ιn the normal pre-pregnancy weight group, when the extra weight gain was >8 kgs, the odds of GDM increased (OR: 2.13, 95%CI: [0.98, 4.21], p = 0.03). Women with pre-pregnancy level 2 clinical obesity (OB2 pre) (BMI > 35 and <40 kg/m²) that shifted to OB3 category (BMI ≥ 40 kg/m²) had an increased GDM likelihood (OR: 4.85, 95%CI: [1.50, 15.95]). Women of higher MA may require stricter monitoring for GDM from early pregnancy, while in obese women, recommended GWG may need to be re-evaluated, since refraining from any weight gain may have a preventive effect for GDM.

The Role of Lifestyle Interventions in the Prevention and Treatment of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is one of the most common pregnancy-related endocrinopathies, affecting up to 25% of pregnancies globally. GDM increases the risk of perinatal and delivery complications, and the chance of developing type 2 diabetes mellitus and its complications, including cardiovascular diseases. This elevated risk is then passed on to the next generation, creating a cycle of metabolic dysfunction across generations. For many years, GDM preventive measures have had inconsistent results, but recent systematic reviews and meta-analyses have identified promising new preventative routes. This review aims to summarize the evidence investigating the efficacy of lifestyle treatments for the prevention of GDM and to summarize the effects of two lifestyle interventions, including physical activity and dietary interventions. Based on the present research, future studies should be conducted to investigate whether initiating lifestyle interventions during the preconception period is more beneficial in preventing GDM. In addition, research targeting pregnancy should be designed with a personalized approach. Therefore, studies should customize intervention approaches depending on the presence of modifiable and non-modifiable risk factors at the individual level.

Acceptability and feasibility of a planned preconception weight loss intervention in women with long-acting reversible contraception: the Plan-it mixed-methods study

BACKGROUND

Women with overweight (a body mass index of ≥ 25 kg/m2) or obesity (a body mass index of ≥ 30 kg/m2) are at greater risk of experiencing complications during pregnancy and labour than women with a healthy weight. Women who remove their long-acting reversible contraception (i.e. coils or implants) are one of the few groups of people who contact services as part of their preparation for conception, creating an opportunity to offer a weight loss intervention.

OBJECTIVES

The objectives were to understand if routine NHS data captured the pathway from long-acting reversible contraception removal to pregnancy and included body mass index; to identify the suitable components of a preconception weight loss intervention; and to engage with key stakeholders to determine the acceptability and feasibility of asking women with overweight/obesity to delay the removal of their long-acting reversible contraception in order to take part in a preconception weight loss intervention.

DESIGN

This was a preparatory mixed-methods study, assessing the acceptability and feasibility of a potential intervention, using routine NHS data and purposefully collected qualitative data.

PARTICIPANTS

The NHS routine data included all women with a long-acting reversible contraception code. There were three groups of participants in the surveys and interviews: health-care practitioners who remove long-acting reversible contraception; weight management consultants; and women of reproductive age with experience of overweight/obesity and of using long-acting reversible contraception.

SETTING

UK-based health-care practitioners recruited at professional meetings; and weight management consultants and contraceptive users recruited via social media.

DATA SOURCES

Anonymised routine data from UK sexual health clinics and the Clinical Practice Research Datalink, including the Pregnancy Register; and online surveys and qualitative interviews with stakeholders.

RESULTS

The records of 2,632,871 women aged 16-48 years showed that 318,040 had at least one long-acting reversible contraception event, with 62% of records including a body mass index. Given the identified limitations of the routine NHS data sets, it would not be feasible to reliably identify women with overweight/obesity who request a long-acting reversible contraception removal with an intention to become pregnant. Online surveys were completed by 100 health-care practitioners, four weight management consultants and 243 contraceptive users. Ten health-care practitioners and 20 long-acting reversible contraception users completed qualitative interviews. A realist-informed approach generated a hypothesised programme theory. The combination of weight discussions and the delay of long-acting reversible contraception removal was unacceptable as an intervention to contraceptive users for ethical and practical reasons. However, a preconception health intervention incorporating weight loss could be acceptable, and one potential programme is outlined.

LIMITATIONS

There was very limited engagement with weight management consultants, and the sample of participating stakeholders may not be representative.

CONCLUSIONS

An intervention that asks women to delay long-acting reversible contraception removal to participate in a preconception weight loss intervention would be neither feasible nor acceptable. A preconception health programme, including weight management, would be welcomed but requires risk communication training of health-care practitioners.

FUTURE WORK

Work to improve routine data sets, increase awareness of the importance of preconception health and overcome health-care practitioner barriers to discussing weight as part of preconception care is a priority.

TRIAL REGISTRATION

This trial is registered as ISRCTN14733020.

FUNDING

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 27, No. 1.

Effectiveness of interventions to increase device-measured physical activity in pregnant women: systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Interventions that provide pregnant women with opportunities to access and participate in physical activity have been shown to be beneficial to their health. Much of this evidence however has been based on self-reported physical activity data, which may be prone to inflated effects due to recall bias and social desirability bias. No previous synthesis of randomised controlled trials has assessed the effectiveness of these interventions using only device measured data, to assess their health benefits more accurately in pregnant women. This systematic review and meta-analysis aimed to address this evidence gap.

DATA SOURCES

Cochrane Central Register of Controlled Trials, Medline, SportDiscus, APA PsycINFO, Embase and Web of Science databases were queried from inception up to December 2, 2021. An updated search of PubMed was conducted on May 16, 2022.

STUDY ELIGIBILITY CRITERIA

Randomised controlled trials that recruited pregnant women, participating in any physical activity intervention (excluding interventions aimed entirely at body conditioning), compared with standard antenatal care (comparators), using device-measured total physical activity as an outcome were eligible for inclusion.

METHODS

3144 titles and abstracts were screened for eligibility, and 18 met the inclusion criteria. Data were analysed using random effect models, (standardised mean difference and mean difference), using data from baseline to last available follow-up (primary end point), and until between 24 to 30 weeks gestation. Gestational weight gain was also assessed at these timepoints in the included trials.

RESULTS

No significant differences between the groups were found for total physical activity at last available follow-up or 24 to 30 weeks gestation (95% CI 0.03 to 0.27, p = 0.10: 95% CI -0.05 to 0.33, p = 0.15) respectively. On average, pregnant women randomised to a physical activity intervention completed 435 and 449 more steps per day than comparators at last available follow-up and at 24 to 30 weeks gestation (95% CI -0.5-870.6, p = 0.05: 95% CI 5.5-892.7, p = 0.05) respectively. Intervention participants also gained 0.69 kg less (95% CI -1.30 to -0.08, p = 0.03) weight than comparators.

CONCLUSION

Based on device-measured data, interventions to promote physical activity during pregnancy have small but important effects on increasing physical activity and managing excessive gestational weight gain.

Addressing Obesity in Preconception, Pregnancy, and Postpartum: A Review of the Literature

PURPOSE OF REVIEW

Reproductive-aged women (aged 19 to 50 years) are a key population warranting focused research for the prevention of overweight and obesity. This review highlights the importance of addressing weight before, during and after pregnancy.

RECENT FINDINGS

Obesity decreases fertility during the preconception period; increases the risk of adverse pregnancy outcomes including gestational diabetes, pre-eclampsia and caesarean section and postpartum weight retention; and increases the long-term health risks for both the mother and offspring. Despite overwhelming efficacy evidence on solutions, there are significant implementation gaps in translating this evidence into pragmatic models of care and real-world solutions. Interventions during preconception, pregnancy and postpartum are likely to be cost-effective or cost-saving, with future investigation needed in the preconception and postpartum period. International clinical guidelines and public health policies are needed for a concerted effort to prevent unhealthy weight gain in these life stages and to reverse the significant adverse health outcomes for women and the next generation.

Exercise During Pregnancy

BACKGROUND

Pregnancy is a good time to motivate women to implement health-promoting behaviors in their everyday lives. There is no official German-language guideline for the counseling of pregnant women by professionals involved in their care. The goal of this review is, therefore, to discuss the links between exercise and gestational diabetes mellitus (GDM), low birth weight, and prematurity.

METHODS

This review is based on pertinent articles retrieved by a systematic search of PubMed and the Web of Science. The articles included in the evaluation were reports of randomized controlled trials (RCTs) and meta-analyses of RCTs of exercise interventions in pregnant women that were published from 1 January 2011 to 15 November 2021.

RESULTS

A structured exercise program during pregnancy can lower the risk of gestational diabetes by as much as 49%. A 25% risk reduction for GDM was achieved with 140 minutes of exercise per week. The mean birth weight was not affected but the rate of excessively heavy newborns was lowered by 32-59% in the normal-weight subgroup. This effect was not seen in the overweight subgroup, possibly because of poorer compliance. Exercise did not elevate the risk of preterm delivery.

CONCLUSION

Regular exercise during pregnancy lessens gestationally induced weight gain and lowers the risk of excessive weight gain, as well as the risk of GDM, without elevating the risk of preterm delivery.

Implementation of Antenatal Lifestyle Interventions Into Routine Care: Secondary Analysis of a Systematic Review

IMPORTANCE

Lifestyle interventions in pregnancy optimize gestational weight gain and improve pregnancy outcomes, with implementation recommended by the US Preventive Services Task Force. Yet, implementation research taking these efficacy trials into pragmatic translation remains limited.

OBJECTIVE

To evaluate success factors for implementing pregnancy lifestyle interventions into antenatal care settings in a meta-analysis, using the penetration, implementation, participation, and effectiveness (PIPE) impact metric.

DATA SOURCES

Data from a previous systematic review that searched across 9 databases, including MEDLINE, Embase, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, and Health Technology Assessment Database, were obtained, in 2 stages, up to May 6, 2020.

STUDY SELECTION

Randomized clinical trials reporting gestational weight gain in singleton pregnancies.

DATA EXTRACTION AND SYNTHESIS

The association of penetration, implementation, and participation with effectiveness of antenatal lifestyle interventions in optimizing gestational weight gain was estimated using random-effects meta-analyses. The Cochrane risk of bias tool, version 1.0, was used to assess risk of bias.

MAIN OUTCOMES AND MEASURES

Penetration (reach), implementation (fidelity), participation, and effectiveness of randomized clinical trials of lifestyle interventions in pregnancy.

RESULTS

Ninety-nine studies with 34 546 participants were included. Only 14 studies reported penetration of target populations. Overall, 38 studies (38.4%) had moderate fidelity, 25 (25.2%) had high fidelity, and 36 (36.4%) had unclear fidelity. Participation was reported in 84 studies (84.8%). Lifestyle interventions were associated with reducing gestational weight gain by 1.15 kg (95% CI, -1.40 to -0.91 kg).

CONCLUSIONS AND RELEVANCE

The findings of this systematic review and meta-analysis suggest that, despite the large body of evidence on efficacy of lifestyle interventions during pregnancy in optimizing gestational weight gain, little guidance is available to inform implementation of this evidence into practice. There is a need to better elucidate implementation outcomes in trial design alongside pragmatic implementation research to improve the health of women who are pregnant and the next generation.

Development and testing of a reduced carbohydrate intervention for the management of obesity and reduction of gestational diabetes (RECORD): protocol for a feasibility randomised controlled trial

INTRODUCTION

Previous trials of dietary interventions to prevent gestational diabetes mellitus (GDM) have yielded only limited success. Low-carbohydrate diets have shown promise for the treatment of type 2 diabetes, but there is no evidence to support their use in pregnancy. The aim of this study is to explore the feasibility of a moderately reduced-carbohydrate dietary intervention delivered from mid-pregnancy alongside routine antenatal care.

METHODS AND ANALYSIS

This is a feasibility randomised controlled trial (RCT) with embedded qualitative study. Sixty women who are pregnant <20 weeks' gestation, with body mass index ≥30 kg/m2 at their antenatal booking appointment, will be randomised 2:1 intervention or control (usual care) and followed up until delivery. The intervention is a moderately reduced-carbohydrate diet (~130-150 g total carbohydrate/day), designed to be delivered alongside routine antenatal appointments. Primary outcomes are measures of adoption of the diet and retention of participants. Secondary outcomes include incidence of GDM, change in markers of glycaemic control, gestational weight gain, total carbohydrate and energy intake. Process outcomes will examine resources and management issues. Exploratory outcomes include further dietary changes, quality of life, maternal and neonatal outcomes, and qualitative measures.

ETHICS AND DISSEMINATION

This trial was reviewed and approved by the South-Central Oxford B Research Ethics Committee NHS National Research Ethics Committee and the Health Research Authority (Reference: 20/SC/0442). The study results will inform whether to progress to a full-scale RCT to test the clinical effectiveness of the RECORD programme to prevent GDM in women at high risk. The findings will be published in peer-reviewed journals and presented at conferences.

TRIAL REGISTRATION NUMBER

ISRCTN16235884.

Effectiveness of exercise intervention during pregnancy on high-risk women for gestational diabetes mellitus prevention: A meta-analysis of published RCTs

Objective

We aimed at investigating the preventive role of exercise intervention during pregnancy, in high-risk women for gestational diabetes mellitus (GDM).

Materials and methods

We searched PubMed, CENTRAL, and Scopus for randomized controlled trials (RCTs) that evaluated exercise interventions during pregnancy on women at high risk for GDM. Data were combined with random effects models. Between study heterogeneity (Cochran’s Q statistic) and the extent of study effects variability [I² with 95% confidence interval (CI)] were estimated. Sensitivity analyses examined the effect of population, intervention, and study characteristics. We also evaluated the potential for publication bias.

Results

Among the 1,508 high-risk women who were analyzed in 9 RCTs, 374 (24.8%) [160 (21.4%) in intervention, and 214 (28.1%) in control group] developed GDM. Women who received exercise intervention during pregnancy were less likely to develop GDM compared to those who followed the standard prenatal care (OR 0.70, 95%CI 0.52, 0.93; P-value 0.02) [Q 10.08, P-value 0.26; I² 21% (95%CI 0, 62%]. Studies with low attrition bias also showed a similar result (OR 0.70, 95%CI 0.51, 0.97; P-value 0.03). A protective effect was also supported when analysis was limited to studies including women with low education level (OR 0.55; 95%CI 0.40, 0.74; P-value 0.0001); studies with exercise intervention duration more than 20 weeks (OR 0.54; 95%CI 0.40, 0.74; P-value 0.0007); and studies with a motivation component in the intervention (OR 0.69, 95%CI 0.50, 0.96; P-value 0.03). We could not exclude large variability in study effects because the upper limit of I² confidence interval was higher than 50% for all analyses. There was no conclusive evidence for small study effects (P-value 0.31).

Conclusions

Our study might support a protective effect of exercise intervention during pregnancy for high-risk women to prevent GDM. The protective result should be corroborated by large, high quality RCTs.

Programming by maternal obesity: a pathway to poor cardiometabolic health in the offspring

There is an ever increasing prevalence of maternal obesity worldwide such that in many populations over half of women enter pregnancy either overweight or obese. This review aims to summarise the impact of maternal obesity on offspring cardiometabolic outcomes. Maternal obesity is associated with increased risk of adverse maternal and pregnancy outcomes. However, beyond this exposure to maternal obesity during development also increases the risk of her offspring developing long-term adverse cardiometabolic outcomes throughout their adult life. Both human studies and those in experimental animal models have shown that maternal obesity can programme increased risk of offspring developing obesity and adipose tissue dysfunction; type 2 diabetes with peripheral insulin resistance and β-cell dysfunction; CVD with impaired cardiac structure and function and hypertension via impaired vascular and kidney function. As female offspring themselves are therefore likely to enter pregnancy with poor cardiometabolic health this can lead to an inter-generational cycle perpetuating the transmission of poor cardiometabolic health across generations. Maternal exercise interventions have the potential to mitigate some of the adverse effects of maternal obesity on offspring health, although further studies into long-term outcomes and how these translate to a clinical context are still required.

Limiting Postpartum Weight Retention in Culturally and Linguistically Diverse Women: Secondary Analysis of the HeLP-her Randomized Controlled Trial

Postpartum weight retention (PPWR) contributes to maternal obesity development and is more pronounced in culturally and linguistically diverse (CALD) women. Our antenatal healthy lifestyle intervention (HeLP-her) demonstrated efficacy in reducing PPWR in non-Australian-born CALD women compared with Australian-born women. In this secondary analysis, we aimed to examine differences in the intervention effect on behavioral and psychosocial outcomes between Australian-born and non-Australian-born women and explore factors associated with the differential intervention effect on PPWR. Pregnant women at risk of gestational diabetes (Australian-born n = 86, non-Australian-born n = 142) were randomized to intervention (four lifestyle sessions) or control (standard antenatal care). PPWR was defined as the difference in measured weight between 6 weeks postpartum and baseline (12-15 weeks gestation). Behavioral (self-weighing, physical activity (pedometer), diet (fat-related dietary habits questionnaire), self-perceived behavior changes), and psychosocial (weight control confidence, exercise self-efficacy, eating self-efficacy) outcomes were examined by country of birth. Multivariable linear regression analysis was conducted to assess factors associated with PPWR. The intervention significantly increased self-weighing, eating self-efficacy, and self-perceived changes to diet and physical activity at 6 weeks postpartum in non-Australian-born women, compared with no significant changes observed among Australian-born women. Intervention allocation and decreased intake of snack foods were predictors of lower PPWR in non-Australian-born women. Results indicate that the HeLP-her intervention improved dietary behaviors, contributing to the reduction of PPWR in CALD women. Future translations could prioritize targeting diet while developing more effective strategies to increase exercise engagement during pregnancy in this population.

OptimalMe Intervention for Healthy Preconception, Pregnancy, and Postpartum Lifestyles: Protocol for a Randomized Controlled Implementation Effectiveness Feasibility Trial

Background

Reproductive-aged women are a high-risk population group for accelerated weight gain and obesity development, with pregnancy recognized as a critical contributory life-phase. Healthy lifestyle interventions during the antenatal period improve maternal and infant health outcomes, yet translation and implementation of such interventions into real-world health care settings remains limited.

Objective

We aim to generate key implementation learnings to inform the feasibility of future scale up and determine the effectiveness of intervention delivery methods on engagement, experience, acceptability, knowledge, risk perception, health literacy, and modifiable weight-related health behaviors in women during preconception, pregnancy, and postpartum periods.

Methods

This randomized hybrid implementation effectiveness study will evaluate the penetration, reach, feasibility, acceptability, adoption, and fidelity of a healthy lifestyle intervention (OptimalMe) implemented into, and in partnership with, private health care. Individual health outcomes associated with implementation delivery mode, including knowledge, risk perception, health literacy, self-management, and health behaviors, are secondary outcomes. A total of 300 women aged 18 to 44 years, who are not pregnant but wish to conceive within the next 12 months, and with access to the internet will be recruited. All participants will receive the same digital lifestyle intervention, OptimalMe, which is supported by health coaching and text messages during preconception, pregnancy, and postpartum periods. We will use a parallel 2-arm design to compare telephone with videoconference remote delivery methods for health coaching. Methods are theoretically underpinned by the Consolidated Framework for Implementation Research and outcomes based on the Reach, Engagement, Adaptation, Implementation and Maintenance framework.

Results

The study was approved on August 16, 2019 and has been registered. Recruitment commenced in July 2020, and data collection is ongoing. Results are expected to be published in 2022.

Conclusions

The study’s design aligns with best practice implementation research. Results will inform translation of evidence from randomized controlled trials on healthy lifestyle interventions into practice targeting women across preconception, pregnancy, and postpartum periods. Learnings will target consumers, program facilitators, health professionals, services, and policy makers to inform future scale up to ultimately benefit the health of women across these life-phases.

Trial Registration

Australian and New Zealand Clinical Trial Registry ACTRN12620001053910; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=378243&isReview=true

International Registered Report Identifier (IRRID)

DERR1-10.2196/33625

Encouraging appropriate gestational weight gain in high-risk gravida: A randomized controlled trial

Trial Design

Excessive gestational weight gain (GWG) can increase pregnancy morbidity and is particularly problematic for women with pregestational obesity. A lifestyle modification intervention was introduced to gravida with obesity to decrease excessive GWG as compared to usual care (UC).

Methods

A randomized controlled trial was conducted to improve healthy lifestyle behaviors to manage appropriate GWG. Consenting participants with prepregnancy obesity and singletons ≤17 weeks were randomized to (1) Usual Care (UC): usual written educational materials and counseling by obstetric provider or (2) Enhanced Care (EC): UC plus (a) personalized letter from physician detailing appropriate GWG; (b) access to individualized GWG chart; (c) ongoing counseling with registered dietitian/nutritionist (RDN). The primary outcome was proportion with GWG ≤9.1 kg, as this is upper limit recommended by Institute of Medicine (IOM). Total GWG and GWG as less than/within/greater than IOM recommendations (in aggregate and stratified by obesity class), and pregnancy/neonatal outcomes were evaluated as secondary outcomes.

Results

Analyses included 105 participants in EC and 109 in UC arms. The groups had similar demographics: 46% with class I obesity, 26% class II, and 28% class III. There were no group differences for any GWG, pregnancy, or neonatal outcomes when analyzed in aggregate. As compared to those randomized to the EC arm, participants in UC arm with class I obesity gained 1.4 kg less and those with class II obesity were significantly more likely to gain within IOM guidelines (14.8% vs. 40.0%, adjusted p = 0.04). Participants with class III obesity randomized to EC arm were more likely to gain within IOM guidelines as compared to participants randomized to UC arm (29.0% vs. 6.7%, adjusted p = 0.02).

Conclusion

There were no differences in GWG observed between groups when analyzing participants in aggregate. However, a physician's letter detailing appropriate GWG, patient portal access to a personalized GWG chart, and RDN consultation were helpful for encouraging GWG within IOM guidelines for women with prepregnancy class III obesity. Women with class I or II obesity had better GWG outcomes without these additional interventions.

Efficacy of behavioral interventions in managing gestational weight gain (GWG): A component network meta-analysis

OBJECTIVE

To identify the most effective behavioral components within lifestyle interventions to optimize gestational weight gain (GWG) to inform guidelines, policy and translation into healthcare.

METHODS

Behavioral components were identified from study level data of randomized antenatal lifestyle interventions using a behavioral taxonomy framework and analyzed using component network meta-analysis (NMA). The NMA ranked behavioral combinations hierarchically by efficacy of optimizing GWG. Direct and estimated indirect comparisons between study arms (i.e., control and intervention) and between different component combinations were estimated to evaluate component combinations associated with greater efficacy.

RESULTS

Overall, 32 studies with 11,066 participants were included. Each intervention contained between 3 and 7 behavioral components with 26 different behavioral combinations identified. The majority (n = 24) of combinations were associated with optimizing GWG, with standard mean differences (SMD) ranging from -1.01 kg (95% CI -1.64 to -0.37) and -0.07 kg (-0.38 to 0.24), compared with controls. The behavioral cluster identified as most effective, included components of goals, feedback and monitoring, natural consequences, comparison of outcomes, and shaping knowledge (SMD -1.01 kg [95% CI -1.64 to -0.37]).

CONCLUSION

Findings support the application of goal setting, feedback and monitoring, natural consequences, comparison of outcomes, and shaping knowledge as essential, core components within lifestyle interventions to optimize gestational weight gain.

Association of Antenatal Diet and Physical Activity-Based Interventions With Gestational Weight Gain and Pregnancy Outcomes: A Systematic Review and Meta-analysis

IMPORTANCE

Excessive gestational weight gain (GWG) is common and associated with adverse pregnancy outcomes. Antenatal lifestyle interventions limit GWG; yet benefits of different intervention types and specific maternal and neonatal outcomes are unclear.

OBJECTIVE

To evaluate the association of different types of diet and physical activity-based antenatal lifestyle interventions with GWG and maternal and neonatal outcomes.

DATA SOURCES

A 2-stage systematic literature search of MEDLINE, Embase, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, and Health Technology Assessment Database was conducted from February 1, 2017, to May 31, 2020. Search results from the present study were integrated with those from a previous systematic review from 1990 to February 2017.

STUDY SELECTION

Randomized trials reporting GWG and maternal and neonatal outcomes.

DATA EXTRACTION AND SYNTHESIS

Data were extracted for random-effects meta-analyses to calculate the summary effect estimates and 95% CIs.

MAIN OUTCOMES AND MEASURES

Outcomes were clinically prioritized, with mean GWG as the primary outcome. Secondary outcomes included gestational diabetes, hypertensive disorders of pregnancy, cesarean section, preterm delivery, large or small for gestational age neonates, neonatal intensive care unit admission, or fetal death.

RESULTS

A total of 117 randomized clinical trials of antenatal lifestyle interventions (involving 34 546 women) were included. Overall lifestyle intervention was associated with reduced GWG (-1.15 kg; 95% CI, -1.40 to -0.91), risk of gestational diabetes (odds ratio [OR], 0.79; 95% CI, 0.70-0.89), and total adverse maternal outcomes (OR, 0.89; 95% CI, 0.84-0.94) vs routine care. Compared with routine care, diet was associated with less GWG (-2.63 kg; 95% CI, -3.87 to -1.40) than physical activity (-1.04 kg; 95% CI, -1.33 to -0.74) or mixed interventions (eg, unstructured lifestyle support, written information with weight monitoring, or behavioral support alone) (-0.74 kg; 95% CI, -1.06 to -0.43). Diet was associated with reduced risk of gestational diabetes (OR, 0.61; 95% CI, 0.45-0.82), preterm delivery (OR, 0.43; 95% CI, 0.22-0.84), large for gestational age neonate (OR, 0.19; 95% CI, 0.08-0.47), neonatal intensive care admission (OR, 0.68; 95% CI, 0.48-0.95), and total adverse maternal (OR, 0.75; 95% CI, 0.61-0.92) and neonatal outcomes (OR, 0.44; 95% CI, 0.26-0.72). Physical activity was associated with reduced GWG and reduced risk of gestational diabetes (OR, 0.60; 95% CI, 0.47-0.75), hypertensive disorders (OR, 0.66; 95% CI, 0.48-0.90), cesarean section (OR, 0.85; 95% CI, 0.75-0.95), and total adverse maternal outcomes (OR, 0.78; 95% CI, 0.71-0.86). Diet with physical activity was associated with reduced GWG (-1.35 kg; 95% CI, -1.95 to -0.75) and reduced risk of gestational diabetes (OR, 0.72; 95% CI, 0.54-0.96) and total adverse maternal outcomes (OR, 0.81; 95% CI, 0.69-0.95). Mixed interventions were associated with reduced GWG only.

CONCLUSIONS AND RELEVANCE

This systematic review and meta-analysis found level 1 evidence that antenatal structured diet and physical activity-based lifestyle interventions were associated with reduced GWG and lower risk of adverse maternal and neonatal outcomes. The findings support the implementation of such interventions in routine antenatal care and policy around the world.

Preventing postpartum weight retention following antenatal lifestyle intervention: One year postpartum follow up of the Healthy Lifestyles in Pregnancy (HeLP-her) randomised controlled trial

Antenatal lifestyle interventions optimise gestational weight gain, yet longer-term efficacy on postpartum weight retention is unclear. Overall, 228 pregnant women <15 weeks gestation were randomised to intervention (four behavioural self-management sessions) or control (generic health information). Median weight retention at 12 months postpartum was significantly reduced in the intervention with a between group difference of -2.3 (-2.8 (-5.9 to 0.35) vs -0.5 (-2.6 to 2.1) kg, respectively P < 0.05, (n = 75) ± 6.3 kg vs -0.5 ± 4.7 kg, respectively, P < 0.05) and associated increased self-weighing behaviours, compared with the control group (regular weighing: 68% vs 43%, P < 0.01). Results demonstrate the efficacy of a low-intensity, behavioural lifestyle intervention in limiting postpartum weight retention.

Effective psychological therapies to improve lifestyle behaviors in (pre)pregnant women: A systematic review

Poor lifestyle behaviors impact (pre)pregnant women by affecting pregnancy outcomes and offspring health. This systematic review provides an overview of psychological therapies to support lifestyle behavior changes among (pre)pregnant women. Scientific databases were searched from their inception to 20 December 2020 for studies investigating the effects of psychological therapies on improvements in lifestyle behaviors. Studies were eligible if they included (pre)pregnant women, examined the effects of a psychological therapy on at least one lifestyle behavior and used a control group receiving usual pregnancy care or a non-psychological intervention. Lifestyle behaviors of interest were dietary intake, physical activity, smoking, alcohol consumption, drug use, body weight loss and body weight gain during pregnancy. Pregnancy complications were included as outcome measures. Motivational interviewing (MI) (n = 21), cognitive behavioral therapy (CBT) (n = 8), incentive-based contingency management (IBCM) (n = 9), mindfulness (n = 1) and hypnosis (n = 1) were investigated as lifestyle behavior interventions. The findings revealed that MI was effective in reducing (self-reported) smoking and alcohol consumption and restricting gestational weight gain (GWG). CBT was only studied as an intervention to restrict GWG and the results predominantly confirmed its effectiveness. IBCM showed the strongest effect on reducing smoking and substance use. The studies using hypnosis or mindfulness to reduce smoking or restrict GWG, respectively, showed no associations. The use of psychological therapies to improve lifestyle behaviors among (pre)pregnant women is new and the scientific proof is promising. Before wide implementation is legitimated, more evidence is needed on the consequences of lifestyle change for pregnancy outcomes.

Goals for reaching optimal wellness (GROWell): A clinical trial protocol of a digital dietary intervention for pregnant and postpartum people with prenatal overweight or obesity

Background:

Excess gestational weight gain (EGWG) is associated with multiple pregnancy complications and health risks for birthing people and their infants. Likewise, postpartum weight retention (PPWR), or not losing all pregnancy weight, has long-term health consequences. EGWG among people who enter pregnancy with overweight or obesity have worse obstetric outcomes and increased PPWR compared to women who gain within Institute of Medicine guidelines.

Methods:

This study protocol describes the details of a blinded, randomized clinical trial of GROWell: Goals for Reaching Optimal Wellness, a mHealth tool designed to improve diet quality among people who enter pregnancy with overweight or obese BMIs to help them achieve appropriate GWG and safe postpartum pregnancy weight loss. Individuals with overweight and obesity will be randomly assigned to an attention control or intervention arm. The intervention group will receive personalized, goal-oriented text messages regarding dietary choices, while the attention control group will receive text messages about healthy pregnancy, labor, delivery, and early infancy. Both groups will complete online surveys at baseline, follow up, 3 and 6 months postpartum.

Results and discussion:

Currently, 162 subjects have been enrolled. Outcomes associated with GWG and pregnancy are expected in late 2023, while outcomes on postpartum weight retention GROWell adherence are expected in late 2024. The results of this trial will support the use of an evidence-based mHealth tool to be integrated into clinical practice to reduce EGWG and PPWR among pregnant people with overweight and obese BMIs, a resource that is currently lacking.

Trial registration:

ClinicalTrials.gov identifier: NCT04449432. Registered on June 26, 2020.

Facilitators and barriers to behaviour change within a lifestyle program for women with obesity to prevent excess gestational weight gain: a mixed methods evaluation

Background

Maternal obesity is associated with health risks for women and their babies and is exacerbated by excess gestational weight gain. The aim of this study was to describe women’s experiences and perspectives in attending a Healthy Pregnancy Service designed to optimise healthy lifestyle and support recommended gestational weight gain for women with obesity.

Methods

An explanatory sequential mixed methods study design utilised two questionnaires (completed in early and late pregnancy) to quantify feelings, motivation and satisfaction with the service, followed by semi-structured interviews that explored barriers and enablers of behaviour change. Data were analysed separately and then interpreted together.

Results

Overall, 49 women attending the service completed either questionnaire 1, 2 or both and were included in the analysis. Fourteen women were interviewed. Prior to pregnancy, many women had gained weight and attempted to lose weight independently, and reported they were highly motivated to achieve a healthy lifestyle. During pregnancy, diet changes were reported as easier to make and sustain than exercise changes. Satisfaction with the service was high. Key factors identified in qualitative analysis were: service support enabled change; motivation to change behaviour, social support, barriers to making change (intrinsic, extrinsic and clinic-related), post-partum lifestyle and needs. On integration of data, qualitative and quantitative findings aligned.

Conclusions

The Healthy Pregnancy service was valued by women. Barriers and enablers to the delivery of an integrated model of maternity care that supported healthy lifestyle and recommended gestational weight gain were identified. These findings have informed and improved implementation and further scale up of this successful service model, integrating healthy lifestyle into routine antenatal care of women with obesity.

Trial registration

This trial is registered with the Australian New Zealand Clinical Trials Registry (no.12620000985987). Registration date 30/09/2020, retrospectively registered. http://www.anzctr.org.au/

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04034-7.

Counseling and Behavioral Interventions for Healthy Weight and Weight Gain in Pregnancy: Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Counseling and active behavioral interventions to limit excess gestational weight gain (GWG) during pregnancy may improve health outcomes for women and infants. The 2009 National Academy of Medicine (NAM; formerly the Institute of Medicine) recommendations for healthy GWG vary according to prepregnancy weight category.

OBJECTIVE

To review and synthesize the evidence on benefits and harms of behavioral interventions to promote healthy weight gain during pregnancy to inform the US Preventive Services Task Force recommendation.

DATA SOURCES

Ovid MEDLINE and the Cochrane Library to March 2020, with surveillance through February 2021.

STUDY SELECTION

Randomized clinical trials and nonrandomized controlled intervention studies focused on diet, exercise, and/or behavioral counseling interventions on GWG.

DATA EXTRACTION AND SYNTHESIS

Independent data abstraction and study quality rating with dual review.

MAIN OUTCOMES AND MEASURES

Gestational weight-related outcomes; maternal and infant morbidity and mortality; harms.

RESULTS

Sixty-eight studies (N = 25 789) were included. Sixty-seven studies evaluated interventions during pregnancy, and 1 evaluated an intervention prior to pregnancy. GWG interventions were associated with reductions in risk of gestational diabetes (43 trials, n = 19 752; relative risk [RR], 0.87 [95% CI, 0.79 to 0.95]; absolute risk difference [ARD], -1.6%) and emergency cesarean delivery (14 trials, n = 7520; RR, 0.85 [95% CI, 0.74 to 0.96]; ARD, -2.4%). There was no significant association between GWG interventions and risk of gestational hypertension, cesarean delivery, or preeclampsia. GWG interventions were associated with decreased risk of macrosomia (25 trials, n = 13 990; RR, 0.77 [95% CI, 0.65 to 0.92]; ARD, -1.9%) and large for gestational age (26 trials, n = 13 000; RR, 0.89 [95% CI, 0.80 to 0.99]; ARD, -1.3%) but were not associated with preterm birth. Intervention participants experienced reduced weight gain across all prepregnancy weight categories (55 trials, n = 20 090; pooled mean difference, -1.02 kg [95% CI, -1.30 to -0.75]) and demonstrated lower likelihood of GWG in excess of NAM recommendations (39 trials, n = 14 271; RR, 0.83 [95% CI, 0.77 to 0.89]; ARD, -7.6%). GWG interventions were associated with reduced postpartum weight retention at 12 months (10 trials, n = 3957; mean difference, -0.63 kg [95% CI, -1.44 to -0.01]). Data on harms were limited.

CONCLUSIONS AND RELEVANCE

Counseling and active behavioral interventions to limit GWG were associated with decreased risk of gestational diabetes, emergency cesarean delivery, macrosomia, and large for gestational age. GWG interventions were also associated with modest reductions in mean GWG and decreased likelihood of exceeding NAM recommendations for GWG.

Pregnant Women Living with Obesity: A Cross-Sectional Observational Study of Dietary Quality and Pregnancy Outcomes

Good maternal nutrition is key to optimal maternal and foetal health. A poor-quality diet is often associated with obesity, and the prevalence and severity of maternal obesity has increased significantly in recent years. This study observed dietary intakes in pregnant women living with obesity and assessed the quality of their diet. In total, 140 women with a singleton pregnancy, aged > 18 years and BMI ≥ 35 kg/m², were recruited from antenatal clinics, weighed and completed food diaries at 16-, 28- and 36-weeks' gestation. Clinical data were recorded directly from the women's medical records. Nutrient intake was determined using 'Microdiet^TM', then compared to Dietary Reference Values (DRVs). Energy intakes were comparable with DRVs, but intakes of sugar and saturated fatty acids were significantly higher. Intake of fibre and several key micronutrients (Iron, Iodine, Folate and Vitamin D) were significantly low. Several adverse obstetric outcomes were higher than the general obstetric population. Women with obesity, often considered 'over nourished', may have diets deficient in essential micronutrients, often associated with poor obstetric outcomes. To address the intergenerational transmission of poor health via poor diets warrants a multi-disciplinary approach focusing away from 'dieting' onto positive messages, emphasising key nutrients required for good maternal and foetal health.

Structured supervised exercise training or motivational counselling during pregnancy on physical activity level and health of mother and offspring: FitMum study protocol

INTRODUCTION

A physically active lifestyle during pregnancy improves maternal and offspring health but can be difficult to follow. In Denmark, less than 40% of pregnant women meet physical activity (PA) recommendations. The FitMum study aims to explore strategies to increase PA during pregnancy among women with low PA and assess the health effects of PA. This paper presents the FitMum protocol, which evaluates the effects of structured supervised exercise training or motivational counselling supported by health technology during pregnancy on PA level and health of mother and offspring.

METHODS AND ANALYSIS

A single-site three-arm randomised controlled trial that aims to recruit 220 healthy, pregnant women with gestational age (GA) no later than week 15 and whose PA level does not exceed one hour/week. Participants are randomised to one of three groups: structured supervised exercise training consisting of three weekly exercise sessions, motivational counselling supported by health technology or a control group receiving standard care. The interventions take place from randomisation until delivery. The primary outcome is min/week of moderate-to-vigorous intensity PA (MVPA) as determined by a commercial activity tracker, collected from randomisation until GA of 28 weeks and 0-6 days, and the secondary outcome is gestational weight gain (GWG). Additional outcomes are complementary measures of PA; clinical and psychological health parameters in participant, partner and offspring; analyses of blood, placenta and breastmilk samples; process evaluation of interventions; and personal understandings of PA.

ETHICS AND DISSEMINATION

The study is approved by the Danish National Committee on Health Research Ethics (# H-18011067) and the Danish Data Protection Agency (# P-2019-512). Findings will be disseminated via peer-reviewed publications, at conferences, and to health professionals via science theatre performances.

TRIAL REGISTRATION NUMBER

NCT03679130.

PROTOCOL VERSION

This paper was written per the study protocol version 8 dated 28 August 2019.

The Role of Lifestyle Intervention in the Prevention and Treatment of Gestational Diabetes

Obesity during pregnancy is associated with the development of adverse outcomes, including gestational diabetes mellitus (GDM). GDM is highly associated with obesity and independently increases the risk of both complications during pregnancy and future impaired glycemic control and risk factors for cardiovascular disease for both the mother and child. Despite extensive research evaluating the effectiveness of lifestyle interventions incorporating diet and/or exercise, there remains a lack of definitive consensus on their overall efficacy alone or in combination for both the prevention and treatment of GDM. Combination of diet and physical activity/exercise interventions for GDM prevention demonstrates limited success, whereas exercise-only interventions report of risk reductions ranging from 3 to 49%. Similarly, combination therapy of diet and exercise is the first-line treatment of GDM, with positive effects on maternal weight gain and the prevalence of infants born large-for-gestational age. Yet, there is inconclusive evidence on the effects of diet or exercise as standalone therapies for GDM treatment. In clinical care, women with GDM should be treated with a multidisciplinary approach, starting with lifestyle modification and escalating to pharmacotherapy if needed. Several key knowledge gaps remain, including how lifestyle interventions can be optimized during pregnancy, and whether intervention during preconception is effective for preventing the rising prevalence of GDM.

The Healthy Pregnancy Service to Optimise Excess Gestational Weight Gain for Women with Obesity: A Qualitative Study of Health Professionals' Perspectives

Maternal obesity is associated with health risks for women and their babies, exacerbated by excess gestational weight gain. We describe health professionals’ perspectives in the provision of a Healthy Pregnancy service designed to optimise healthy lifestyle and support recommended gestational weight gain for women with obesity. Semi-structured interviews were conducted with health professionals. Questions were based on the Theoretical Domains Framework (TDF) and deductive thematic analysis was performed. A total of 14 multidisciplinary staff were interviewed. Six themes were identified: 1. health professionals view themselves as part of a team; 2. health professionals reported having necessary skills; 3. experience generated confidence in discussing gestational weight gain; 4. gestational weight gain is considered of variable importance; 5. health professionals want women to be comfortable; 6. the environmental context and resources presented some barriers. Staff were supportive of the Healthy Pregnancy service and valued developing teamwork with staff and rapport with women. Most felt relatively comfortable discussing weight gain with women. Barriers included ability to navigate sensitive topics with women, limited awareness of the intervention among new staff, communication between teams, and waiting time for women. Barriers and enablers to the delivery of an integrated model of maternity care were identified. These findings should inform and improve implementation of service models integrating healthy lifestyle in the antenatal care of women with obesity.

The Design of a Randomized Clinical Trial to Evaluate a Pragmatic and Scalable eHealth Intervention for the Management of Gestational Weight Gain in Low-Income Women: Protocol for the SmartMoms in WIC Trial

BACKGROUND

Less than one-third of women gain an appropriate amount of weight during pregnancy, which can influence the long-term health of both the mother and the child. Economically disadvantaged women are the most vulnerable to maternal obesity, excessive weight gain during pregnancy, and poor birth outcomes. Effective and scalable health care strategies to promote healthy weight gain during pregnancy specifically tailored for these women are lacking.

OBJECTIVE

This paper presents the design and protocol of a biphasic, community-based eHealth trial, SmartMoms in WIC, to increase the adherence to healthy gestational weight gain (GWG) recommendations in low-income mothers receiving women, infant, and children (WIC) benefits.

METHODS

Phase 1 of the trial included using feedback from WIC mothers and staff and participants from 2 community peer advisory groups to adapt an existing eHealth gestational weight management intervention to meet the needs of women receiving WIC benefits. The health curriculum, the format of delivery, and incentive strategies were adapted to be culturally relevant and at an appropriate level of health literacy. Phase 2 included a pragmatic randomized controlled trial across the 9 health care regions in Louisiana with the goal of enrolling 432 women. The SmartMoms in WIC intervention is an intensive 24-week behavioral intervention, which includes nutrition education and exercise strategies, and provides the technology to assist with weight management, delivered through a professionally produced website application.

RESULTS

Phase 1 of this trial was completed in July 2019, and recruitment for phase 2 began immediately thereafter. All data are anticipated to be collected by Spring 2023.

CONCLUSIONS

The SmartMoms in WIC curriculum was methodically developed using feedback from community-based peer advisory groups to create a culturally relevant, mobile behavioral intervention for mothers receiving WIC benefits. The randomized clinical trial is underway to test the effectiveness of a sustainable eHealth program on the incidence rates of appropriate GWG. SmartMoms in WIC may be able to offer an innovative, cost-effective, and scalable solution for GWG management in women served by WIC.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04028843; https://clinicaltrials.gov/ct2/show/NCT04028843.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/18211.

Cost Effectiveness of Antenatal Lifestyle Interventions for Preventing Gestational Diabetes and Hypertensive Disease in Pregnancy

BACKGROUND

Lifestyle interventions (diet, physical activity and/or behavioural) to optimise gestational weight gain can prevent adverse maternal outcomes such as gestational diabetes, pre-eclampsia and caesarean section.

OBJECTIVE

We aimed to model the cost effectiveness of lifestyle interventions during pregnancy on reducing adverse maternal outcomes.

METHODS

Decision tree modelling was used to determine the cost effectiveness of lifestyle interventions compared with usual care on preventing cases of gestational diabetes and hypertensive disease in pregnancy. Participants were pregnant women receiving routine antenatal care in secondary and tertiary care hospitals. The main outcome measures were cases of gestational diabetes and/or hypertensive disease in pregnancy prevented, costs, and incremental cost-effectiveness ratios. Analysis was conducted from the perspective of the Australian healthcare system, with a time horizon of early pregnancy to discharge after birth.

RESULTS

Women in the intervention group were 2.25% less likely to have gestational diabetes and/or hypertensive disease in pregnancy (9.53%) compared with the control group (11.78%). Intervention costs were Australian dollars (AUD) 228 per person. Costs were AUD33 per person higher in the intervention group (AUD8281) than the control group (AUD8248). The incremental cost-effectiveness ratio was AUD1470 per case prevented. Sensitivity analysis showed that base-case results were robust. In the probabilistic sensitivity analysis, 44.8% of data points fell within the north-east quadrant, and 52.2% in the south-east quadrant (cost saving), with a 95% confidence interval ranging from AUD - 50,018 to 32,779 per case prevented.

CONCLUSIONS

While there is no formally accepted cost-effectiveness threshold for willingness-to-pay to prevent an adverse maternal event, the cost per person receiving a lifestyle intervention compared with controls was close to neutral, and therefore likely to be cost effective. Exploration of the cost effectiveness of different lifestyle delivery modes across various models of antenatal care is now required. Future cost-effectiveness studies should investigate longer time horizons, quality-adjusted life-years and productivity loss.

TRIAL REGISTRATION

Not applicable.

Relationships between Total, Free and Bioavailable Vitamin D and Vitamin D Binding Protein in Early Pregnancy with Neonatal Outcomes: A Retrospective Cohort Study

Maternal vitamin D deficiency has been associated with adverse neonatal outcomes, however, existing results are inconsistent. Current data focus on total 25-hydroxyvitamin D (25(OH)D) as the common measure of vitamin D status, while additional measures including vitamin D-binding protein (VDBP) and free and bioavailable metabolites have not been explored in relation to neonatal outcomes. We examined whether VDBP and total, free, and bioavailable vitamin D metabolites in early pregnancy are associated with subsequent neonatal outcomes. In this retrospective analysis of 304 women in early pregnancy (<20 weeks gestation), demographic and anthropometric data were collected and total 25(OH)D (chemiluminescent assay), VDBP (polyclonal enzyme-linked immunosorbent assay (ELISA)) and albumin (automated colorimetry) were measured in bio-banked samples. Free and bioavailable 25(OH)D were calculated using validated formulae. Neonatal outcomes were derived from a medical record database. Higher maternal total and free 25(OH)D concentrations were associated with higher neonatal birthweight (β = 5.05, p = 0.002 and β = 18.06, p = 0.02, respectively), including after adjustment for maternal covariates including age, body mass index (BMI) and ethnicity (all p ≤ 0.04). Higher total 25(OH)D and VDBP concentrations were associated with a lower likelihood of neonatal jaundice (odds ratio [OR] [95%CI] = 0.997 [0.994, 1.000], p = 0.04 and 0.98 [0.96, 0.99], p = 0.03, respectively), but these were attenuated after adjustment for the above maternal covariates (both p = 0.09). Our findings suggest a novel association between free 25(OH)D and neonatal birthweight. Total 25(OH)D concentrations were also associated with birthweight, and both total 25(OH)D and VDBP were associated with jaundice, but the latter were not significant after adjustment. These results suggest a potential link between these metabolites and neonatal outcomes; however, further large-scale prospective studies are warranted.

Early Pregnancy Vitamin D Binding Protein Is Independently Associated with the Development of Gestational Diabetes: A Retrospective Cohort Study

BACKGROUND

Vitamin D-binding protein (VDBP) has been implicated in several adverse pregnancy outcomes either directly or indirectly via influencing the concentrations of biologically active vitamin D metabolites. However, human studies exploring these metabolites in pregnancy remain sparse. Here, we examine whether VDBP and total, free, and bioavailable 25-hydroxyvitamin D (25(OH)D) metabolites in early pregnancy are associated with subsequent adverse pregnancy outcomes.

METHODS

We conducted a retrospective analysis of 304 pregnant women in early pregnancy (<20 weeks gestation). The demographic characteristics, anthropometric data, and total 25(OH)D were measured and plasma or serum samples were collected and bio-banked. Using these samples, we measured VDBP (polyclonal ELISA) and albumin (automated colorimetry), and calculated free and bioavailable 25(OH)D using validated formulae. Pregnancy outcomes were derived from scanned medical records. Regression models were used to analyse the relationships between vitamin D metabolites in early pregnancy and subsequent pregnancy outcomes (gestational diabetes mellitus (GDM), pre-eclampsia, preterm birth), with adjustment for predetermined clinically relevant maternal factors including age, body mass index (BMI), and ethnicity.

RESULTS

Lower VDBP concentrations were associated with higher glucose levels and a greater likelihood of developing GDM at 26-28 weeks gestation (odds ratio [OR] (95% CI) = 0.98 (0.97,0.99), p = 0.015). This finding remained significant after adjustment for maternal covariates including age, BMI, and ethnicity (β = -0.003, p = 0.03). Lower total, free and bioavailable 25(OH)D, but not VDBP, were associated with a shorter length of gestation, but only the relationship with total 25(OH)D remained significant after adjustment for the above maternal covariates (β = 0.02, p = 0.006).

CONCLUSIONS

This is the first study to examine VDBP, and total, free and bioavailable 25(OH)D in relation to pregnancy outcomes in a well characterised multi-ethnic cohort of pregnant women. Our findings show that VDBP and total 25(OH)D are associated with GDM and length of gestation, respectively; however, further investigations using large-scale prospective studies are needed to confirm our findings.

Interventions including a nutrition component aimed at managing gestational weight gain or postpartum weight retention: a systematic review and meta-analysis

OBJECTIVES

The objective of this systematic review was to evaluate the effectiveness of interventions that include a nutrition component aimed at improving gestational weight gain and/or postpartum weight retention.

INTRODUCTION

Excessive gestational weight gain and postpartum weight retention increase the risk of adverse maternal and neonatal outcomes. Current evidence comprises many interventions targeting gestational weight gain and postpartum weight retention that incorporate a nutrition component. To date, no review has synthesized evidence from pregnancy through the postpartum period or described the intervention approaches in detail.

INCLUSION CRITERIA

The review included women (≥18 years) during pregnancy and/or up to 12 months postpartum. Studies were included if they involved a weight management intervention with a nutrition component and had the primary objective of determining the impact of gestational weight gain and/or postpartum weight change. Interventions were compared to usual care (i.e. control conditions with no intervention or wait-list control or standard pregnancy or postpartum care) or "other" (alternative intervention). The review considered randomized controlled trials published between 1980 and January 21, 2016. Studies that included a weight related primary outcome measured during pregnancy and/or postpartum were included.

METHODS

Seven databases were searched and the reference lists of included studies were searched for additional studies not previously identified. Two independent reviewers assessed the methodological quality of studies using the Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instrument (JBI SUMARI). The JBI SUMARI standardized data extraction tool was used to extract data. A narrative synthesis was undertaken to qualitatively synthesize included studies, with meta-analyses used to pool weight outcome data from studies conducted separately for pregnancy and postpartum. Effect sizes for meta-analyses have been expressed as weighted mean differences (95% confidence intervals).

RESULTS

The search yielded 4063 articles of which 48 articles from 39 studies were included. Eleven of 20 studies during pregnancy reported significant reductions in gestational weight gain with the intervention when compared to control groups. One of five studies where the intervention was conducted during both pregnancy and postpartum reported statistically significant reductions in gestational weight gain, and postpartum weight retention between intervention and control groups. Nine of 14 studies conducted after childbirth reported statistically significant intervention effects, indicating lesser postpartum weight retention. Random effects meta-analyses indicated that despite considerable heterogeneity, interventions conducted during pregnancy (-1.25 kg; 95% CI: -2.10 kg, -0.40 kg; p = 0.004), and postpartum (-3.25 kg; 95% CI: -4.69 kg, -1.82 kg; p < 0.001) were significantly more effective at improving weight outcomes compared to usual care or other interventions. Most studies were of moderate quality due to lack of clarity in describing study details required for appraising methodological quality. Few interventions were conducted from pregnancy through the postpartum period (n = 5). Limited interventions adopted online modalities in intervention delivery (n = 4). Intention-to-treat analysis was used in only 12 studies.

CONCLUSIONS

The pregnancy and postpartum period presents a unique opportunity to engage women in interventions to help optimize lifestyle behaviors for weight management, however the optimal approach is unclear. Improving consistency in intervention implementation and reporting will improve future evidence synthesis.

Interventions to prevent women from developing gestational diabetes mellitus: an overview of Cochrane Reviews

BACKGROUND

The prevalence of gestational diabetes mellitus (GDM) is increasing, with approximately 15% of pregnant women affected worldwide, varying by country, ethnicity and diagnostic thresholds. There are associated short- and long-term health risks for women and their babies.

OBJECTIVES

We aimed to summarise the evidence from Cochrane systematic reviews on the effects of interventions for preventing GDM.

METHODS

We searched the Cochrane Database of Systematic Reviews (6 August 2019) with key words 'gestational diabetes' OR 'GDM' to identify reviews pre-specifying GDM as an outcome. We included reviews of interventions in women who were pregnant or planning a pregnancy, irrespective of their GDM risk status. Two overview authors independently assessed eligibility, extracted data and assessed quality of evidence using ROBIS and GRADE tools. We assigned interventions to categories with graphic icons to classify the effectiveness of interventions as: clear evidence of benefit or harm (GRADE moderate- or high-quality evidence with a confidence interval (CI) that did not cross the line of no effect); clear evidence of no effect or equivalence (GRADE moderate- or high-quality evidence with a narrow CI crossing the line of no effect); possible benefit or harm (low-quality evidence with a CI that did not cross the line of no effect or GRADE moderate- or high-quality evidence with a wide CI); or unknown benefit or harm (GRADE low-quality evidence with a wide CI or very low-quality evidence).

MAIN RESULTS

We included 11 Cochrane Reviews (71 trials, 23,154 women) with data on GDM. Nine additional reviews pre-specified GDM as an outcome, but did not identify GDM data in included trials. Ten of the 11 reviews were judged to be at low risk of bias and one review at unclear risk of bias. Interventions assessed included diet, exercise, a combination of diet and exercise, dietary supplements, pharmaceuticals, and management of other health problems in pregnancy. The quality of evidence ranged from high to very low. Diet Unknown benefit or harm: there was unknown benefit or harm of dietary advice versus standard care, on the risk of GDM: risk ratio (RR) 0.60, 95% CI 0.35 to 1.04; 5 trials; 1279 women; very low-quality evidence. There was unknown benefit or harm of a low glycaemic index diet versus a moderate-high glycaemic index diet on the risk of GDM: RR 0.91, 95% CI 0.63 to 1.31; 4 trials; 912 women; low-quality evidence. Exercise Unknown benefit or harm: there was unknown benefit or harm for exercise interventions versus standard antenatal care on the risk of GDM: RR 1.10, 95% CI 0.66 to 1.84; 3 trials; 826 women; low-quality evidence. Diet and exercise combined Possible benefit: combined diet and exercise interventions during pregnancy versus standard care possibly reduced the risk of GDM: RR 0.85, 95% CI 0.71 to 1.01; 19 trials; 6633 women; moderate-quality evidence. Dietary supplements Clear evidence of no effect: omega-3 fatty acid supplementation versus none in pregnancy had no effect on the risk of GDM: RR 1.02, 95% CI 0.83 to 1.26; 12 trials; 5235 women; high-quality evidence. Possible benefit: myo-inositol supplementation during pregnancy versus control possibly reduced the risk of GDM: RR 0.43, 95% CI 0.29 to 0.64; 3 trials; 502 women; low-quality evidence. Possible benefit: vitamin D supplementation versus placebo or control in pregnancy possibly reduced the risk of GDM: RR 0.51, 95% CI 0.27 to 0.97; 4 trials; 446 women; low-quality evidence. Unknown benefit or harm: there was unknown benefit or harm of probiotic with dietary intervention versus placebo with dietary intervention (RR 0.37, 95% CI 0.15 to 0.89; 1 trial; 114 women; very low-quality evidence), or probiotic with dietary intervention versus control (RR 0.38, 95% CI 0.16 to 0.92; 1 trial; 111 women; very low-quality evidence) on the risk of GDM. There was unknown benefit or harm of vitamin D + calcium supplementation versus placebo (RR 0.33, 95% CI 0.01 to 7.84; 1 trial; 54 women; very low-quality evidence) or vitamin D + calcium + other minerals versus calcium + other minerals (RR 0.42, 95% CI 0.10 to 1.73; 1 trial; 1298 women; very low-quality evidence) on the risk of GDM. Pharmaceutical Possible benefit: metformin versus placebo given to obese pregnant women possibly reduced the risk of GDM: RR 0.85, 95% CI 0.61 to 1.19; 3 trials; 892 women; moderate-quality evidence. Unknown benefit or harm:eight small trials with low- to very low-quality evidence showed unknown benefit or harm for heparin, aspirin, leukocyte immunisation or IgG given to women with a previous stillbirth on the risk of GDM. Management of other health issues Clear evidence of no effect: universal versus risk based screening of pregnant women for thyroid dysfunction had no effect on the risk of GDM: RR 0.93, 95% CI 0.70 to 1.25; 1 trial; 4516 women; moderate-quality evidence. Unknown benefit or harm: there was unknown benefit or harm of using fractional exhaled nitrogen oxide versus a clinical algorithm to adjust asthma therapy on the risk of GDM: RR 0.74, 95% CI 0.31 to 1.77; 1 trial; 210 women; low-quality evidence. There was unknown benefit or harm of pharmacist led multidisciplinary approach to management of maternal asthma versus standard care on the risk of GDM: RR 5.00, 95% CI 0.25 to 99.82; 1 trial; 58 women; low-quality evidence.

AUTHORS' CONCLUSIONS

No interventions to prevent GDM in 11 systematic reviews were of clear benefit or harm. A combination of exercise and diet, supplementation with myo-inositol, supplementation with vitamin D and metformin were of possible benefit in reducing the risk of GDM, but further high-quality evidence is needed. Omega-3-fatty acid supplementation and universal screening for thyroid dysfunction did not alter the risk of GDM. There was insufficient high-quality evidence to establish the effect on the risk of GDM of diet or exercise alone, probiotics, vitamin D with calcium or other vitamins and minerals, interventions in pregnancy after a previous stillbirth, and different asthma management strategies in pregnancy. There is a lack of trials investigating the effect of interventions prior to or between pregnancies on risk of GDM.

Exercise and insulin resistance in PCOS: muscle insulin signalling and fibrosis

OBJECTIVE

Mechanisms of insulin resistance in polycystic ovary syndrome (PCOS) remain ill defined, contributing to sub-optimal therapies. Recognising skeletal muscle plays a key role in glucose homeostasis we investigated early insulin signalling, its association with aberrant transforming growth factor β (TGFβ)-regulated tissue fibrosis. We also explored the impact of aerobic exercise on these molecular pathways.

METHODS

A secondary analysis from a cross-sectional study was undertaken in women with (n = 30) or without (n = 29) PCOS across lean and overweight BMIs. A subset of participants with (n = 8) or without (n = 8) PCOS who were overweight completed 12 weeks of aerobic exercise training. Muscle was sampled before and 30 min into a euglycaemic-hyperinsulinaemic clamp pre and post training.

RESULTS

We found reduced signalling in PCOS of mechanistic target of rapamycin (mTOR). Exercise training augmented but did not completely rescue this signalling defect in women with PCOS. Genes in the TGFβ signalling network were upregulated in skeletal muscle in the overweight women with PCOS but were unresponsive to exercise training except for genes encoding LOX, collagen 1 and 3.

CONCLUSIONS

We provide new insights into defects in early insulin signalling, tissue fibrosis, and hyperandrogenism in PCOS-specific insulin resistance in lean and overweight women. PCOS-specific insulin signalling defects were isolated to mTOR, while gene expression implicated TGFβ ligand regulating a fibrosis in the PCOS-obesity synergy in insulin resistance and altered responses to exercise. Interestingly, there was little evidence for hyperandrogenism as a mechanism for insulin resistance.

Health in Preconception, Pregnancy and Postpartum Global Alliance: International Network Pregnancy Priorities for the Prevention of Maternal Obesity and Related Pregnancy and Long-Term Complications

In this article, we describe the process of establishing agreed international pregnancy research priorities to address the global issues of unhealthy lifestyles and rising maternal obesity. We focus specifically on the prevention of maternal obesity to improve related clinical pregnancy and long-term complications. A team of multidisciplinary, international experts in preconception and pregnancy health, including consumers, were invited to form the Health in Preconception, Pregnancy and Postpartum (HiPPP) Global Alliance. As an initial activity, a priority setting process was completed to generate pregnancy research priorities in this field. Research, practice and policy gaps were identified and enhanced through expert and consumer consultation, followed by a modified Delphi process and Nominal Group Technique, including an international workshop. Research priorities identified included optimising: (1) healthy diet and nutrition; (2) gestational weight management; (3) screening for and managing pregnancy complications and pre-existing conditions; (4) physical activity; (5) mental health; and (6) postpartum (including intrapartum) care. Given extensive past research in many of these areas, research priorities here recognised the need to advance pregnancy research towards pragmatic implementation research. This work has set the agenda for large-scale, collaborative, multidisciplinary, implementation research to address the major public health and clinical issue of maternal obesity prevention.

Supporting women of childbearing age in the prevention and treatment of overweight and obesity: a scoping review of randomized control trials of behavioral interventions

BACKGROUND

Women of childbearing age are vulnerable to weight gain. This scoping review examines the extent and range of research undertaken to evaluate behavioral interventions to support women of childbearing age to prevent and treat overweight and obesity.

METHODS

Eight electronic databases were searched for randomized controlled trials (RCT) or systematic reviews of RCTs until 31st January 2018. Eligible studies included women of childbearing age (aged 15-44 years), evaluated interventions promoting behavior change related to diet or physical activity to achieve weight gain prevention, weight loss or maintenance and reported weight-related outcomes.

RESULTS

Ninety studies met the inclusion criteria (87 RCTs, 3 systematic reviews). Included studies were published from 1998 to 2018. The studies primarily focused on preventing excessive gestational weight gain (n = 46 RCTs, n = 2 systematic reviews), preventing postpartum weight retention (n = 18 RCTs) or a combination of the two (n = 14 RCTs, n = 1 systematic review). The RCTs predominantly evaluated interventions that aimed to change both diet and physical activity behaviors (n = 84) and were delivered in-person (n = 85).

CONCLUSIONS

This scoping review identified an increasing volume of research over time undertaken to support women of childbearing age to prevent and treat overweight and obesity. It highlights, however, that little research is being undertaken to support the young adult female population unrelated to pregnancy or preconception.

Effects of a lifestyle intervention in routine care on prenatal physical activity - findings from the cluster-randomised GeliS trial

BACKGROUND

Excessive gestational weight gain (GWG) is associated with an increased risk of pregnancy and obstetric complications. The "healthy living in pregnancy" (GeliS) study was performed in a routine care setting with the aim of limiting excessive GWG. The purpose of this secondary analysis is to evaluate the effect of the intervention on physical activity (PA) behaviour and to assess the impact of PA intensities on GWG.

METHODS

The cluster-randomised, multicentre GeliS trial was performed in a routine care setting alongside scheduled prenatal visits. Pregnant women with a pre-pregnancy BMI between 18.5 and 40.0 kg/m2 were either assigned to the control group receiving usual care or to the intervention group. Participants in the intervention group attended three antenatal counselling sessions on diet and PA and one additional postpartum session. Data on PA behaviour were collected twice, before the end of the 12th (baseline) and after the 29th week of gestation using the Pregnancy Physical Activity Questionnaire.

RESULTS

PA data were available for 1061 (93%) participants in the intervention and 1040 (93%) in the control group. Women in the intervention group reported significant improvements in the levels of total PA (p < 0.001), total PA of light intensity and above (p < 0.001), moderate-intensity (p = 0.024) and vigorous-intensity activities (p = 0.002) as well as sport activities (p < 0.001) in late pregnancy compared to the control group. The proportion of women meeting the international PA recommendations in late pregnancy was significantly higher in the intervention (64%) versus the control group (49%, p < 0.001). Activities of light-intensity and above (p = 0.006), light-intensity (p = 0.002) and vigorous-intensity (p = 0.014) in late pregnancy were inversely associated with total GWG.

CONCLUSION

We found significant evidence of improvements in the PA pattern of pregnant women receiving lifestyle counselling within the framework of routine care. Most PA intensities were inversely associated with total GWG which indicates that PA across different intensities should be promoted.

TRIAL REGISTRATION

NCT01958307, ClinicalTrials.gov, retrospectively registered 9 October, 2013.

"It's not easy" - A qualitative study of lifestyle change during pregnancy

BACKGROUND

Maternal lifestyle in the months leading up to conception and throughout pregnancy has both immediate and transgenerational impacts on offspring health.

AIM

To explore how women's lifestyles change when they become pregnant, and their perspectives of the lifestyle advice they receive throughout pregnancy.

METHODS

A descriptive qualitative approach was used. Semi-structured interviews with 17 childbearing women (mean gestational age, 30.2 ± 2.0 weeks) recruited from a large hospital network in Victoria, Australia between July and October 2018 were transcribed and analysed using an inductive process of thematic analysis.

FINDINGS

Three themes and six sub-themes were identified. Lifestyle change during pregnancy was highly influenced by participants' preconception lifestyle, the physiological demands of pregnancy and the pressures of daily life. While participants proactively sought lifestyle advice from a range of sources, including the Internet, they were generally less proactive in seeking advice during routine maternity care visits. Participants appreciated the lifestyle advice they received from health professionals, including midwives, as part of their maternity care despite acknowledging that they often received it only if they asked. Overall, it seemed that the lifestyle advice received from health professionals was much less influential on maternal lifestyle behaviour change than the broader socio-ecological environment.

CONCLUSION

Childbearing women want lifestyle advice that supports positive lifestyle change during pregnancy and health professionals, including midwives, must be proactive as they provide it. Other factors that impact on childbearing women's capability and opportunity to make lifestyle change should be considered when providing advice that supports positive lifestyle behaviour change.

β-3 adrenergic receptor gene polymorphisms are associated with gestational diabetes mellitus in a Chinese population

Increasing studies demonstrated that genetic susceptibility attributes to the development of gestational diabetes mellitus (GDM). The polymorphisms of the β-3 adrenergic receptor(β-3AR) gene have been found to be of great importance in bodyweight elevation and dyslipidaemias. We aimed to determine the influence of β-3AR polymorphisms on the GDM risk. Thus, we performed a case-control study including 136 GDM cases and 138 controls to evaluate the relation between the rs201607471 and susceptibility to GDM. Likelihood ratios X analysis showed the distribution of the genotype frequency (rs201607471 in β-3AR gene) was accorded with the Hardy-Weinberg genetic equilibrium. Although no significant association between rs201607471 alleles and GDM susceptibility (Chi-square test, P > .05), we observed that β-3AR gene rs201607471 CT genotype was significantly prevalent in GDM (Chi-square test, P < .05). Moreover, we observed that β-3AR gene rs201607471 C > T was significantly associated with an increased risk of GDM using the recessive model (CC vs CT/TT: P = .026) and the additive model (CC vs CT vs TT: P = .038). These data indicate that β-3AR rs201607471 may be a helpful susceptibility marker for GDM in Chinese pregnant women.