Prenatal exercise for the prevention of gestational diabetes mellitus and hypertensive disorders of pregnancy: a systematic review and meta-analysis

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.

Physical activity differentially regulates VEGF, PlGF, and their receptors in the human placenta

Physical activity (PA) has beneficial effects on the function of many organs by modulating their vascular development. Regular PA during pregnancy is associated with favorable short‐ and long‐term outcomes for both mother and fetus. During pregnancy, appropriate vascularization of the placenta is crucial for adequate maternal–fetal nutrient and gas exchange. How PA modulates angiogenic factors, VEGF, and its receptors in the human placenta, is as of yet, unknown. We objectively measured the PA of women at 24–28 and 34–38 weeks of gestation. Participants were considered “active” if they had met or exceeded 150 min of moderate‐intensity PA per week during their 2nd trimester. Term placenta tissues were collected from active (n = 23) or inactive (n = 22) women immediately after delivery. We examined the expression of the angiogenic factors VEGF, PlGF, VEGFR‐1, and VEGFR‐2 in the placenta. Western blot analysis showed VEGF and its receptor, VEGFR‐1 was significantly (p < 0.05) higher both at the protein and mRNA levels in placenta from physically active compared to inactive women. No difference in VEGFR‐2 was observed. Furthermore, immunohistochemistry showed differential staining patterns of VEGF and its receptors in placental endothelial, stromal, and trophoblast cells and in the syncytial brush border. In comparison, PlGF expression did not differ either at the protein or mRNA level in the placenta from physically active or inactive women. The expression and localization pattern of VEGF and its receptors suggest that PA during pregnancy may support a pro‐angiogenic milieu to the placental vascular network.

Markers of branched-chain amino acid catabolism are not affected by exercise training in pregnant women with obesity

Despite the role of branched-chain amino acids (BCAAs) in physiological processes such as nutrient signaling and protein synthesis, there is ongoing debate about the link between circulating BCAAs and insulin resistance (IR) in various populations. In healthy women, IR mildly increases during pregnancy, whereas both BCAAs and markers of BCAA catabolism decrease, indicating that fetal growth is being prioritized. Exercise reduces IR in nonpregnant adults, but less is known about the effect of exercise during pregnancy in women with obesity on IR and BCAA breakdown. The aim of this study was to determine the effect of a moderate-intensity exercise intervention during pregnancy on maternal circulating BCAAs and markers of BCAA catabolism [short-chain acylcarnitines (ACs)], and their associations with IR. Healthy obese [n = 80, means ± SD; body mass index (BMI): 36.9 ± 5.7 kg/m²] pregnant women were randomized into an exercise (n = 40, aerobic/resistance 3×/wk, ∼13th gestation week until birth) or a nonexercise control (n = 40) group. Blood was collected at 12.2 ± 0.5 and 36.0 ± 0.4 gestation weeks and analyzed for BCAA-derived acylcarnitine concentrations as markers of BCAA breakdown toward oxidative pathways, and glucose and insulin concentrations [updated homeostatic model assessment of IR (HOMA2-IR)]. After adjusting for HOMA2-IR, there were no interaction effects of group by time. In addition, there was a main positive effect of time on HOMA2-IR (12 wk: 2.3 ± 0.2, 36 wk: 3.0 ± 0.2, P = 0.003). A moderate-intensity exercise intervention during pregnancy in women with obesity was not associated with changes in BCAA-derived ACs versus standard of care. The decrease in BCAA-derived ACs throughout gestation could not be explained by IR.NEW & NOTEWORTHY This research showed an increase in insulin resistance (IR) and decrease in branched-chain amino acid catabolism throughout gestation in women with obesity, and addition of a moderate exercise intervention (known to attenuate IR in nonpregnant populations) did not alter these shifts. Findings provide support for metabolic safety of exercise during pregnancy.

Correlation Analysis between GDM and Gut Microbial Composition in Late Pregnancy

The prevalence of GDM is very high worldwide. The specific pathogenesis of GDM is currently not very clear. Recent research suggests that changes in the intestinal flora during pregnancy play a key role in it. Therefore, this study is aimed at exploring the characteristics of the intestinal flora of patients with gestational diabetes in the third trimester of pregnancy and at finding the intestinal flora with significant differences in healthy pregnant women to provide a basis for future clinical attempts of using intestinal microecological agents to treat gestational diabetes mellitus (GDM). We sequenced the V3-V4 regions of the 16S ribosomal ribonucleic acid (rRNA) gene from stool samples of 52 singleton pregnant women at >28 weeks of gestation. Our results showed that there were significant differences between the NOR group vs. GDM group and the G group vs. LG group among Bacteroides, Firmicutes, and Firmicutes/Bacteroides. At the species level, there were significant differences in the abundance of eight species in the NOR and GDM groups. Among them, the relative abundance of Clostridium_spiroforme, Eubacterium_dolichum, and Ruminococcus_gnavus was positively correlated with FBG, and Pyramidobacter_piscolens was negatively correlated with FBG, whereas there were significant differences in the abundance of five species in the G and LG groups. Functional analysis showed that there were differences in the biosynthesis and metabolism of polysaccharides, digestive system, classification, and degradation of the intestinal microbes between the NOR and GDM groups and between the G and LG groups. These results indicated that the gut microbes between GDM patients in the third trimester of pregnancy and healthy controls had essential characteristic changes and might be involved in the regulation of patients' blood glucose levels.

Non-Coding RNAs and Extracellular Vehicles: Their Role in the Pathogenesis of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is defined as glucose intolerance with onset or first recognition in the second or third trimester of pregnancy. GDM has a considerable impact on health outcomes of the mother and offspring during pregnancy, delivery, and beyond. Although the exact mechanism regarding GDM remains unclear, numerous studies have suggested that non-coding RNAs, including long non-coding (lnc)RNAs, microRNAs, and circular RNAs, were involved in the pathogenesis of GDM in which they played vital regulatory roles. Additionally, several studies have revealed that extracellular vehicles also participated in the pathogenesis of GDM, highlighting their important role in this disease. Considering the lack of effective biomarkers for the early identification of and specific treatment for GDM, non-coding RNAs and extracellular vehicles may be promising biomarkers and even targets for GDM therapies. This review provides an update on our understanding of the role of non-coding RNAs and extracellular vehicles in GDM. As our understanding of the function of lncRNAs and extracellular vehicles improves, the future appears promising for their use as potential biomarkers and treatment targets for GDM in clinical practice.

Is yoga considered exercise within systematic reviews of exercise interventions? A scoping review

OBJECTIVE

Yoga is an increasingly popular choice of exercise for the Western population, with people engaging in yoga for a range of physical and mental health and well-being reasons. The aim of this scoping review is to examine whether yoga is considered an exercise modality within relevant leading journals, as evidenced by its consideration in systematic reviews (SRs) of exercise interventions for health-related outcomes.

METHODS

Design: Scoping review.

DATA SOURCES

Three leading sources (Sports Medicine, British Journal of Sports Medicine and Cochrane Collaboration) were searched. Eligibility criteria for selecting studies: The ten most recently published systematic reviews of exercise interventions for health-related outcomes from each journal were included (N = 30) that met these criteria: systematic review studying humans participating in general exercise and measuring a health-related outcome. Exercise interventions with any specific qualifying terms (e.g. aquatic, strength, aerobic) were excluded.

RESULTS

The articles retrieved were published between 2007 and 2019, and collectively included 991 interventions. Seven reviews explicitly stated that yoga was to be included/excluded while twenty-three studies made no mention of how yoga was being considered in the methodology. Five studies included yoga in the search strategy, implying its inclusion. Post-hoc analyses found that the definitions of exercise in general were also variable. Exercise definition specificity was not associated with whether or not yoga was assessed for inclusion.

CONCLUSIONS

Systematic reviews of exercise and physical activity interventions for health-related outcomes do not consistently make clear whether or not they include or exclude yoga as a form of exercise.

Association of high maternal triglyceride levels early and late in pregnancy with adverse outcomes: A retrospective cohort study

BACKGROUND

Excess maternal triglyceride (mTG) exposure during early or late pregnancy increases risks of adverse pregnancy outcomes. However, it is inconclusive whether persistently high maternal triglyceride during whole pregnancy has more negative associations.

OBJECTIVE

To explore whether persistently high maternal triglyceride (mTG) levels from early to late pregnancy further increases the risk of adverse pregnancy outcomes.

METHODS

We included 12,715 women who had a singleton birth and who underwent routine serum lipid screenings in both early (9-13 weeks) and late (28-42 weeks) pregnancy during May 2018 to July 2019 in a university-based maternity center. Risks for gestational diabetes mellitus (GDM), preeclampsia, preterm delivery, small/large for gestational age (LGA) were estimated.

RESULTS

Elevated mTG levels during early pregnancy were associated with increased risks of preterm delivery (AOR, 1.52; 95% CI, 1.21 to 1.90), preeclampsia (1.75; 1.29 to 2.36), gestational diabetes mellitus (1.95; 1.69 to 2.25), and LGA (1.28; 1.12 to 1.46). Compared with those with low mTG levels both in the 1st and 3rd trimesters, persistently high mTG levels increased the risks of preeclampsia (2.53; 1.66 to 3.84), GDM (1.97; 1.57 to 2.47), and LGA (1.68; 1.37 to 2.07). However, persistently high mTG levels only slightly increased risk of LGA when compared with high mTG levels during the 1st trimester alone (1.34, 1.01 to 1.77).

CONCLUSIONS

Elevated mTG levels during early pregnancy not in late pregnancy could be the crucial risk factor associated with adverse pregnancy outcomes. These results suggest the importance of lipid screenings and preventions during early pregnancy, which may help to improve pregnancy outcomes.

Exercise during pregnancy mitigates negative effects of parental obesity on metabolic function in adult mouse offspring

Parental health influences embryonic development and susceptibility to disease in the offspring. We investigated whether maternal voluntary running during gestation could protect the offspring from the adverse effects of maternal or paternal high-fat diet (HF) in mice. We performed transcriptomic and whole-genome DNA methylation analyses in female offspring skeletal muscle and targeted DNA methylation analysis of the peroxisome proliferator-activated receptor-γ coactivator-1α (Pgc-1α) promoter in both male and female adult offspring. Maternal HF resulted in impaired metabolic homeostasis in male offspring at 9 mo of age, whereas both male and female offspring were negatively impacted by paternal HF. Maternal exercise during gestation completely mitigated these metabolic impairments. Female adult offspring from obese male or female parent had skeletal muscle transcriptional profiles enriched in genes regulating inflammation and immune responses, whereas maternal exercise resulted in a transcriptional profile similar to offspring from normal chow (NC)-fed parents. Maternal HF, but not paternal HF, resulted in hypermethylation of the Pgc-1α promoter at CpG-260, which was abolished by maternal exercise. These findings demonstrate the negative consequences of maternal and paternal HF for the offspring's metabolic outcomes later in life possibly through different epigenetic mechanisms, and maternal exercise during gestation mitigates the negative consequences.NEW & NOTEWORTHY Maternal or paternal obesity causes metabolic impairment in adult offspring in mice. Maternal exercise during gestation can completely mitigate metabolic impairment. Maternal obesity, but not paternal obesity, results in hypermethylation of the Pgc-1α promoter at CpG-260, which can be abolished by maternal exercise.

Treadmill Running of Mouse as a Model for Studying Influence of Maternal Exercise on Offspring

Epidemiological studies robustly show the beneficial effects of maternal exercise in reducing maternal birth complications and improving neonatal outcomes, though underlying mechanisms remain poorly understood. To facilitate mechanistic exploration, a protocol for maternal exercise of mice is established, with the regimen following the exercise guidelines for pregnant women. Compared to volunteer wheel running, treadmill running allows precise control of exercise intensity and duration, dramatically reducing variations among individual mouse within treatments and facilitating translation into maternal exercise in humans. Based on the maximal oxygen consumption rate (VO₂max) before pregnancy, the treadmill exercise protocol is separated into three stages: early stage (E1.5 to E7.5 at 40% VO₂max), mid stage (E8.5 to E14.5 at 65% VO₂max), and late stage of pregnancy (E15.5 to birth at 50% VO₂max), which demonstrated persistent beneficial effects on maternal health and fetal development. This protocol can be useful for standardizing maternal treadmill exercise using mice as an experimental model.

Applying the Ecological Model to understand pregnant women's perspectives on the modifiable constraints to physical activity during pregnancy: A qualitative research study

The benefits of physical activity (PA) during pregnancy are widely reported; however, PA practice is seemingly not a valued habit among pregnant women attending public antenatal health centres in the Eastern Cape of South Africa. Guided by the ecological model, we sought to explore modifiable barriers to PA among pregnant women.Semi-structured interviews involved a purposive sample of 15 pregnant women. Interview questions were guided by the ecological model constructs at intrapersonal, interpersonal, and environmental level. Thematic analysis was applied to summarise the modifiable barriers to PA during pregnancy.Three main themes emerged, based on the modifiable barriers to PA during pregnancy that belong to the varying Ecological Model constructs. On the intrapersonal level, 5 themes emerged, namely, time-constraint beliefs, feeling of tiredness, low energy, lack of motivation, and a lack of knowledge on benefits and types of PA. Two themes emerged for the interpersonal level, lack of PA advice and lack of information on PA recommendations and guidelines. Another theme defined the environmental level lacking resources. Most themes related to individual factors, which prevent PA-promoting behaviour.Overall, intrapersonal factors relating to tiredness and exhaustion, lack of time beliefs, work and household commitments, and lack of motivation were key modifiable barriers to PA by the women. The findings provide insights into possible interventional strategies to optimise PA during pregnancy among women in this setting. Appropriate knowledge, education and advice on the benefits, types, and intensity of PA in pregnancy are needed.

Physical activity and exercise during pregnancy in Africa: a review of the literature

BACKGROUND

Pregnancy is an important phase in a woman's life, with health status at this stage affecting both the woman and her child's life. Global evidence suggests that many women engage in low levels of physical activity (PA) and exercise during pregnancy despite its beneficial effects. This is particularly the case in Africa.

METHODS

This article reviews the literature on levels of PA and exercise among pregnant women in Africa, highlighting the level of PA or exercise participation during pregnancy in Africa, including types of PA, factors affecting PA, beliefs about and benefits of prenatal activity, advice or counselling on PA during pregnancy in Africa, and PA interventions proposed to promote the uptake of prenatal PA. Electronic search databases used were Google Scholar, Science Direct, Scopus, EMBASE, ERIC, Medline, Web of Science, EBSCOhost, PubMed, BIOMED Central, and African Journal Online. The basic search terms were: 'Physical activity', 'Exercise', 'Pregnancy', 'Pregnant women' and 'Africa'. A total of 40 references were found. On the basis of an analysis of titles, abstracts and the language of publication (other than English), 11 articles were rejected, and 29 articles were fully read, although two had to be rejected due to a lack of access to the full version. Finally, 27 references were included in the review.

RESULTS

Few studies exist on PA during pregnancy in Africa. The limited data available suggests that, compared to the Western world, pregnant women in Africa do not adhere to the recommendations for PA during pregnancy. Levels of participation in PA during pregnancy are low and decline as the pregnancy progresses. The majority of the studies used direct, objective measures to assess PA during pregnancy. Personal and environmental factors such as lack of time, lack of knowledge, inadequate information from healthcare providers, feelings of tiredness and an absence of social support constituted the main barriers to PA during pregnancy. The types of PA participation among pregnant women varied across studies and geographical settings.

CONCLUSIONS

While published data is limited, it seems clear that the participation of pregnant women in PA during pregnancy in Africa is low and declines with advancing pregnancy. There is a need for more studies to examine the dynamics of PA during pregnancy in Africa to guide contextual interventions to improve and promote maternal health on the continent.

Prenatal Exercise and Cardiorespiratory Health and Fitness: A Meta-analysis

PURPOSE

This study aimed to examine the influence of prenatal exercise on maternal cardiorespiratory health and fitness during pregnancy.

METHODS

Online databases were searched up to February 25, 2019. Studies of randomized controlled trials (RCTs) were eligible, which contained information on the relevant population (pregnant women), intervention (subjective or objective measures of frequency, intensity, duration, volume, or type of exercise), comparator (no exercise intervention), and outcomes (maternal cardiorespiratory fitness, including V˙O2max, submaximal V˙O2, V˙O2 at anaerobic threshold, and cardiorespiratory health, including resting heart rate, and resting systolic and diastolic blood pressures during pregnancy).

RESULTS

From 2699 unique citations, 26 RCTs (N = 2292 women) were included. Of these, one study reported measured V˙O2max, seven reported predicted V˙O2max, three reported submaximal V˙O2, and two studies reported VO2AT. "Low"- to "high"-certainty evidence revealed that exercise was associated with improved predicted/measured V˙O2max (5 RCTs, n = 430; mean difference [MD], 2.77 mL·kg·min; 95% confidence interval [CI], 0.32 to 5.21 mL·kg·min; I = 69%), reduced resting heart rate (9 RCTs, n = 637; MD, -1.71 bpm; 95% CI, -3.24 to -0.19 bpm; I = 13%), resting systolic blood pressure (16 RCTs, n = 1672; MD, -2.11 mm Hg; 95% CI, -3.71 to -0.51 mm Hg; I = 69%), and diastolic blood pressure (15 RCTs, n = 1624; MD, -1.77 mm Hg; 95% CI, -2.90 to -0.64 mm Hg; I = 60%).

CONCLUSION

Prenatal exercise interventions improve maternal predicted/measured V˙O2max and reduce resting heart rate and blood pressure. This review highlights the need for additional high-quality studies of cardiorespiratory fitness (namely, V˙O2max and V˙O2 peak) in pregnancy.PROSPERO registration number: CRD42019131249.

Physical Activity Level during Pregnancy in South Africa: A Facility-Based Cross-Sectional Study

Physical activity participation during pregnancy confers many maternal and foetal health benefits to the woman and her infant and is recommended by various health bodies and institutions. However, in South Africa, scant information exists about the physical activity status and its determinants among pregnant women. The aim of this study was to assess the physical activity level and associated factors among pregnant women. This cross-sectional study enrolled 1082 pregnant women attending public health facilities in Buffalo City Municipality, Eastern Cape, South Africa. Information on socio-demographic and maternal characteristics were obtained, and the Pregnancy Physical Activity Questionnaire was used to assess physical activity during pregnancy. Multiple logistic regression analyses were used to assess associations between physical activity and the predictor variables during pregnancy. Adjusted odds ratios with 95% confidence interval were applied to estimate factors associated with physical activity levels. Statistical significance was set at p < 0.05. Only 278 of the women (25.7%) met recommendations for prenatal activity (≥150 min moderate intensity exercise per week). The average time spent in moderate-vigorous physical activity was 151.6 min (95% CI: 147.2-156.0). Most of the women participated in light exercises with a mean of 65.9% (95% CI: 64.8-67.0), and 47.6% (95% CI: 46.3-48.9) participated in household activities. The majority of the women did not receive physical activity advice during prenatal care sessions (64.7%). Factors negatively associated with prenatal physical activity were lower age (<19 years) (adjusted odd ratio (AOR) = 0.3; CI: 0.16-0.76), semi-urban residence (AOR = 0.8; CI: 0.55-1.03), lower educational level (AOR = 0.5; CI: 0.20-0.71), unemployment (AOR = 0.5; CI: 0.29-0.77) and nulliparity (AOR = 0.6; CI: 0.28-1.31). However, prenatal physical activity was positively associated with starting physical activity in the first trimester (AOR = 1.9; CI: 1.06-3.31) compared to other trimesters. The findings of this study demonstrated low levels of physical activity during pregnancy in South Africa. The majority of women did not meet the recommendation of 150 min of moderate intensity activity per week. Light intensity and household activities were the most preferred form of activity. The factors affecting physical activity of women in this present study include lower age, semi-urban setting, low educational level, unemployment and nulliparity. In order to increase activity levels, future work should seek to improve knowledge, access and support for physical activity in pregnant women in South Africa. This should include education and advocacy regarding physical activity for professionals involved in maternal health provision.

Lifestyle interventions for the prevention and treatment of hypertension

Hypertension affects approximately one third of the world's adult population and is a major cause of premature death despite considerable advances in pharmacological treatments. Growing evidence supports the use of lifestyle interventions for the prevention and adjuvant treatment of hypertension. In this Review, we provide a summary of the epidemiological research supporting the preventive and antihypertensive effects of major lifestyle interventions (regular physical exercise, body weight management and healthy dietary patterns), as well as other less traditional recommendations such as stress management and the promotion of adequate sleep patterns coupled with circadian entrainment. We also discuss the physiological mechanisms underlying the beneficial effects of these lifestyle interventions on hypertension, which include not only the prevention of traditional risk factors (such as obesity and insulin resistance) and improvements in vascular health through an improved redox and inflammatory status, but also reduced sympathetic overactivation and non-traditional mechanisms such as increased secretion of myokines.

Blood Test Results of Pregnant COVID-19 Patients: An Updated Case-Control Study

Background: Coronavirus disease (COVID-19) is a current global public health emergency. However, current research on the blood test results of pregnant women with COVID-19 is insufficient. Methods: A case-control study was carried out based on clinical blood test results. Pregnant COVID-19 patients, pregnant COVID-19 patients with diabetes, and pregnant COVID-19 patients with hypertension, were assessed in this study. Also, 120 controls were matched by age, parity, fetus number, and presence of chronic disease. T-tests, Chi-square tests, Wilcoxon signed-rank tests, and Kruskal-Wallis tests were used to compare data from the blood tests and liver function indices among the selected groups. Results: Between January 24 and March 14, 2020, 60 pregnant COVID-19 patients delivered at the Maternal and Child Health Hospital of Hubei Province. The average maternal age of pregnant COVID-19 patients was 30.97 years and the mean gestational period was 37.87 weeks. 71.67% (43/60) of pregnant COVID-19 patients gave birth by cesarean delivery. In total, 21.67% (13/60) were diagnosed with diabetes and 18.33% (11/60) were diagnosed with hypertension during pregnancy. Compared to controls, pregnant COVID-19 patients showed significantly lower numbers of blood lymphocytes and higher numbers of neutrophils, as well as higher levels of C-reactive protein and total bilirubin. Among the three groups, pregnant COVID-19 patients with diabetes had significantly higher levels of neutrophils and lower levels of total protein. Aspartate transaminase levels were higher in pregnant COVID-19 patients with hypertension than in pregnant COVID-19 patients with no comorbidities and controls with hypertension. Interpretations: Blood and liver function indices indicate that chronic complications, including hypertension and diabetes, could increase the risk of inflammation and liver injury in pregnant COVID-19 patients.

Knowledge translation and social media: Twitter data analysis of the 2019 Canadian Guideline for Physical Activity throughout Pregnancy

OBJECTIVES

Despite extensive evidence demonstrating the benefits of prenatal physical activity (PA), inefficient knowledge translation may contribute to low rates of PA during pregnancy. This study aimed to examine the impact of the 2019 Canadian Guideline for Physical Activity throughout Pregnancy (hereafter Guideline) on knowledge transmission via Twitter.

METHODS

Tweets containing keywords regarding prenatal PA were mined using the Twitter Application Programming Interface 1 month prior to (PRE), and 2 months following (POST-Month1 and Month2) Guideline release (October 18, 2018). The volume, user and location of Tweets relevant to prenatal PA were analyzed.

RESULTS

In this 3-month period, 19,944 Tweets were collected. After randomization to select 10% of the sample, 1995 Tweets were analyzed. Tweets related to prenatal PA increased following Guideline release (PRE = 318/674 [45%]; POST-Month1 = 377/755 [50%]); however, this was not sustained into POST-Month2 (202/566 [36%]). The main users Tweeting about prenatal PA were categorized as 'General Population' (33%), whereas top users Tweeting about the Guideline were 'Academics' (25%), 'Exercise Specialists' (27%) and 'Medical Professionals' (20%). POST-Guideline, Tweets originated from users in 42 countries (PRE = 28).

CONCLUSIONS

Twitter can be an effective tool for knowledge transmission of PA guidelines to a variety of end-users around the globe.

Adaptation of an exercise intervention for pregnant women to community-based delivery: a study protocol

INTRODUCTION

Despite well-established guidelines and benefits to exercise, the majority of pregnant women in the USA fail to meet recommended activity levels. Studies need to determine feasible ways to translate clinical interventions to community settings by engaging pregnant women in widely accessible locations to ensure benefits to more women. The aim of this study is to adapt and determine feasibility, acceptability and fidelity of the research clinic-based Expecting intervention (NCT02125149) with pregnant women with obesity in community settings.

METHODS AND ANALYSIS

We will use the Replicating Effective Programs (REP) to guide the adaptation and implementation of the research clinic-based intervention into the community. REP provides a four-phase process for implementing evidence-based interventions including collection of feedback from community stakeholders, iterative piloting of the intervention in the community and a process for standardising the intervention across community settings. Following adaptation, the updated intervention will be piloted. The pilot study will include 60 expecting women. We will randomise half to receive the community-adapted Expecting intervention (intervention, N=30) and half to receive standard of care (control, N=30). Feasibility and Acceptability of Intervention Measures are primary outcomes as key indicators of feasibility. Secondary outcomes will include the number of intervention sessions completed, the change in the number of minutes of physical activity as measured by accelerometer, as well as change in health indicators from enrolment to time of delivery and 6 months post-delivery (ie, body mass index, blood pressure and total cholesterol).

ETHICS AND DISSEMINATION

This study has been approved by the Institutional Review Board (#260132). Findings will be shared with study participants and stakeholder advisors through written summaries and in-person presentations; results will also be shared through presentations at scientific conferences and publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT04298125; Pre-results.

Effects of maternal and paternal exercise on offspring metabolism

Maternal and paternal obesity and type 2 diabetes are recognized risk factors for the development of metabolic dysfunction in offspring, even when the offspring follow a healthful lifestyle. Multiple studies have demonstrated that regular physical activity in mothers and fathers has striking beneficial effects on offspring health, including preventing the development of metabolic disease in rodent offspring as they age. Here, we review the benefits of maternal and paternal exercise in combating the development of metabolic dysfunction in adult offspring, focusing on offspring glucose homeostasis and adaptations to metabolic tissues. We discuss recent findings regarding the roles of the placenta and sperm in mediating the effects of parental exercise on offspring metabolic health, as well as the mechanisms hypothesized to underlie these beneficial changes. Given the worldwide epidemics of obesity and type 2 diabetes, if these findings translate to humans, regular exercise during the reproductive years might limit the vicious cycles in which increased metabolic risk propagates across generations.

Physical Activity Programs during Pregnancy Are Effective for the Control of Gestational Diabetes Mellitus

Gestational diabetes mellitus has an incidence of 14% worldwide and nursing is responsible for its monitoring during pregnancy. Excessive weight gain during pregnancy is directly related to gestational diabetes mellitus development. Gestational diabetes mellitus (GDM) has negative repercussions on the evolution of the pregnancy and the fetus. The objective of this systematic review is to establish how physical activity influences pregnant women with gestational diabetes mellitus and to analyze what benefits physical activity has in the control of gestational diabetes mellitus. A systematic search was carried out in different databases (Cochrane, Superior Council of Scientific Investigations (CSIC), EBSCOhost, Pubmed, Scopus, Web os Science, and Proquest) for papers published within the last 12 years, taking into account different inclusion and exclusion criteria. Six randomized controlled studies and one observational case-control study of a high quality were selected. Fasting, postprandial glucose and HbcA1 were assessed, as well as the requirement and amount of insulin used. Thus, there is a positive relationship between the performance of physical activity and the control of gestational diabetes mellitus. Resistance, aerobic exercise, or a combination of both are effective for the control of glucose, HbcA1, and insulin. Due to the variability of the exercises of the analyzed studies and the variability of the shape of the different pregnant women, it does not permit the recommendation of a particular type of exercise. However, any type of physical activity of sufficient intensity and duration can have benefits for pregnant women with GDM. Pregnant women with gestational diabetes mellitus should exercise for at least 20–50 min a minimum of 2 times a week with at a least moderate intensity.

Maternal physical activity significantly alters the placental transcriptome

INTRODUCTION

Maternal lifestyle, in particular physical activity (PA), influences many of the physiological adaptations during pregnancy associated with feto-placental development and growth. There is limited to no information on the link between PA during pregnancy and the molecular mechanisms governing placental function. The aim of this study was to investigate the molecular mechanisms through which maternal PA may influence placental function.

METHODS

The level of PA was measured by accelerometry and gene expression was measured in term placenta with custom polymerase chain reaction (PCR) arrays and microarray analysis followed by a pathway analyses on significantly differentially expressed genes (DEGs).

RESULTS

Microarray analysis showed 43 significantly DEGs between active and non-active participants. RT-qPCR validation of a sub-sample of DEGs revealed significant changes in the level of expression between active and non-active moms (student's t-test, p < 0.05, n = 11). Genes involved in transport of water (p = 0.00236) and uptake of glycerol (p = 0.00219) were enriched in active moms. PA was also associated with the alteration of alternative splicing patters. The most consistent splicing changes were observed for AQP9 where active moms lacked exon 2.

DISCUSSION

Variations in maternal PA influences placental gene. We show significant expression changes of genes that are involved in transport and localization between active and non-active women. Most notably, the expression of the aquaporin family of genes (e.g. AQP1 and AQP9) were found to be significantly higher in the placentas of active women suggesting an adaptive response for the transport of water and glycerol in this population.

The effects of aerobic exercise on markers of maternal metabolism during pregnancy

BACKGROUND

Optimal maternal metabolism during pregnancy is essential for healthy fetal growth and development. Chronic exercise is shown to positively affect metabolism, predominantly demonstrated in nonpregnant populations.

OBJECTIVE

To determine the effects of aerobic exercise on maternal metabolic biomarkers during pregnancy, with expected lower levels of glucose, insulin, and lipids among exercise-trained pregnant women.

METHODS

Secondary data analyses were performed using data from two, longitudinal prenatal exercise intervention studies (ENHANCED by MOM and GESTAFIT). Exercisers completed 150 min of weekly moderate-intensity exercise during pregnancy (24+ weeks) while nonexercisers attended stretching sessions. Pregnant women were 31-33 years of age, predominantly non-Hispanic white, and "normal weight" body mass index. At 16 and 36 weeks of gestation, fasting blood samples were collected via fingerstick and venipuncture. Maternal glucose, insulin, insulin resistance (HOMA-IR), total cholesterol (TC), low-density lipoproteins (LDL), high-density lipoproteins (HDL), and triglycerides (TG) were analyzed. ANCOVA analyses were performed to evaluate the effects of aerobic exercise on markers of maternal metabolism in late pregnancy, controlling for baseline levels.

RESULTS

Our sample included 12 aerobic exercisers and 54 nonexercising control groups. Significant between-groups differences at 16 weeks of gestation were found for TG (92.3 vs. 121.2 mg/dl, p = .04), TC (186.8 vs. 219.6 mg/dl, p = .002), and LDL (104.1 vs. 128.8 mg/dl, p = .002). Aerobic-trained pregnant women exhibited lower insulin levels in late pregnancy (β = -2.6 μIU/ml, 95% CI:-4.2, -0.95, p = .002) and a reduced increase in insulin levels from 16 to 36 week of gestation (β = -2.3 μIU/ml, 95% CI: -4.4, -0.2, p = .034) compared with nonexercising pregnant women. No statistically significant effects were observed for maternal HOMA-IR, TC, LDL, HDL, TC:HDL, and TG in late pregnancy.

CONCLUSIONS

The observations of this study demonstrate that prenatal exercise may positively affect maternal insulin, with aerobic-trained pregnant women exhibiting lower insulin levels in late pregnancy. Additionally, we found no appreciable effects of prenatal exercise on maternal lipids in late pregnancy.

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.

Why can't I exercise during pregnancy? Time to revisit medical 'absolute' and 'relative' contraindications: systematic review of evidence of harm and a call to action

BACKGROUND

Clinical guidelines recommend pregnant women without contraindication engage in regular physical activity. This is based on extensive evidence demonstrating the safety and benefits of prenatal exercise. However, certain medical conditions or contraindications warrant a reduction, modification or cessation of activity due to potential health risks.

AIM

To review and evaluate the evidence related to medical disorders which may warrant contraindication to prenatal exercise.

METHODS

Online databases were searched up to 5 April 2019. Forty-four unique studies that reported data on our Population (pregnant women with contraindication to exercise), Intervention (subjective/objective measures of acute or chronic exercise), Comparator (not essential) and Outcomes (adverse maternal or fetal outcomes) were included in the review.

KEY FINDINGS

We found that the majority of medical conditions listed as contraindications were based on expert opinion; there is minimal empirical evidence to demonstrate harm of exercise and benefit of activity restriction. We identified 11 complications (eg, gestational hypertension, twin pregnancy) previously classified as contraindications where women may in fact benefit from regular prenatal physical activity with or without modifications. However, the evidence suggests that severe cardiorespiratory disease, placental abruption, vasa previa, uncontrolled type 1 diabetes, intrauterine growth restriction, active preterm labour, severe pre-eclampsia and cervical insufficiency are associated with strong potential for maternal/fetal harm and warrant classification as absolute contraindications.

CONCLUSION

Based on empirical evidence, we provide a call to re-evaluate clinical guidelines related to medical disorders that have previously been considered contraindications to prenatal exercise. Removing barriers to physical activity during pregnancy for women with certain medical conditions may in fact be beneficial for maternal-fetal health outcomes.

The Effect of Exercise Training During Pregnancy to Improve Maternal Vascular Health: Focus on Gestational Hypertensive Disorders

Hypertensive disorders of pregnancy, including gestational hypertension and pre-eclampsia, occur in up to 10% of pregnancies and are associated with increased life-long cardiovascular risk. Physical activity improves cardiovascular health in pregnancy and may lower the risk of developing hypertensive disorders of pregnancy. However, a minority of pregnant women comply with the recommended level of physical activity. Adequate knowledge on the physiological effects of exercise in healthy pregnancy could help to overcome potential barriers as pregnancy is a unique window of opportunity to improve health outcomes for both mother and child. In this mini review, we discuss structural and functional vascular adaptations during healthy and hypertensive pregnancies, we elaborate on the effects of exercise on the vasculature and review the safety and existing evidence of exercise training as preventive therapy for gestational hypertensive disorders.

Physical activity, sedentary behavior and development of preeclampsia in women with preexisting diabetes

AIMS

To explore the association between physical activity in early pregnancy and development of preeclampsia in women with preexisting diabetes.

METHODS

In a prospective cohort study of 189 women with preexisting diabetes (110 type 1 and 79 type 2 diabetes), physical activity during pregnancy including sedentary behavior was evaluated with the Pregnancy Physical Activity Questionnaire. Primary outcome was preeclampsia. Secondary outcomes were preterm delivery, large and small for gestational age infants.

RESULTS

Women developing preeclampsia (n = 23) had higher diastolic blood pressure in early pregnancy (mean 82 ± 9 SD vs. 77 ± 8, p = 0.004) and were more often nulliparous (91 vs. 52%, p < 0.001) compared with the remaining women (n = 166). Total physical activity in early pregnancy was similar between the groups (median 148 metabolic equivalent of task hours per week (MET-h/week) (interquartile range 118-227) versus 153 (121-205), p = 0.97). In early pregnancy, women developing preeclampsia reported a higher level of sedentary behavior (15 MET-h/week (7-18) versus 7 (4-15); p = 0.04); however, when adjusting for parity, diastolic blood pressure and smoking, the association attenuated (p = 0.13). Total physical activity and sedentary behavior in early pregnancy were not associated with preterm delivery, large or small for gestational age infants.

CONCLUSIONS

Among women with diabetes, sedentary behavior was reported higher in early pregnancy in women developing preeclampsia compared with the remaining women, while total physical activity was similar. Sedentary behavior was a predictor of preeclampsia in the univariate analysis, but not in the multiple regression analysis, and larger studies are needed to evaluate this possible modifiable risk factor. Trial registration The study was registered at ClinicalTrials.gov (ID: NCT02890836).

Animal Models of Preeclampsia: Causes, Consequences, and Interventions

Preeclampsia is a common pregnancy complication, affecting 2% to 8% of pregnancies worldwide, and is an important cause of both maternal and fetal morbidity and mortality. Importantly, although aspirin and calcium are able to prevent preeclampsia in some women, there is no cure apart from delivery of the placenta and fetus, often necessitating iatrogenic preterm birth. Preclinical models of preeclampsia are widely used to investigate the causes and consequences of preeclampsia and to evaluate safety and efficacy of potential preventative and therapeutic interventions. In this review, we provide a summary of the published preclinical models of preeclampsia that meet human diagnostic criteria, including the development of maternal hypertension, together with new-onset proteinuria, maternal organ dysfunction, and uteroplacental dysfunction. We then discuss evidence from preclinical models for multiple causal factors of preeclampsia, including those implicated in early-onset and late-onset preeclampsia. Next, we discuss the impact of exposure to a preeclampsia-like environment for later maternal and progeny health. The presence of long-term impairment, particularly cardiovascular outcomes, in mothers and progeny after an experimentally induced preeclampsia-like pregnancy, implies that later onset or reduced severity of preeclampsia will improve later maternal and progeny health. Finally, we summarize published intervention studies in preclinical models and identify gaps in knowledge that we consider should be targets for future research.

Physical activity and blood pressure during pregnancy: Mediation by anxiety symptoms

BACKGROUND

During pregnancy, physiological systems and psychological perceptions vary across individuals. Prenatal physical activity has been linked to reduced anxiety symptoms and lower blood pressure values. However, whether anxiety symptoms can mediate the relationship between physical activity and blood pressure during pregnancy remains unclear.

METHODS

In this prospective cohort study, 1275 pregnant women enrolled in Nanjing, China. Life behaviours and anxiety symptoms were investigated during the first trimester. Anxiety symptoms were measured by the Self-Rating Anxiety Scale. Blood pressure values were taken during the third trimester. Multivariate linear regression models were used to estimate the associations of physical activity with anxiety symptoms and blood pressure, and mediating effect models were used to detect the regulating effect by anxiety.

RESULTS

The participants were assigned to 3 groups based on their frequency and intensity of physical activity, and those who engaged in regular physical activity had lower blood pressure values. Anxiety symptoms were milder in the regular group than in the insufficient group. Partial mediating effect of anxiety on the association between regular physical activity and systolic blood pressure was significant after accounting for some confounders.

LIMITATIONS

The participants' physical activity and anxiety symptoms were self-reported, as well as the lack of details of physical activity during pregnancy may restrict the power of our findings.

CONCLUSIONS

Regular physical activity might be beneficial for anxiety and blood pressure. Physical activity likely stabilises systolic blood pressure by alleviating anxiety symptoms. Our research could provide a positive theoretical reference for guiding prenatal care.

The impact of occupational activities during pregnancy on pregnancy outcomes: a systematic review and metaanalysis

OBJECTIVE

Data: An increasing number of studies suggest that exposure to physically demanding work during pregnancy could be associated with increased risks of adverse pregnancy outcomes, but the results remain conflicted and inconclusive. The purpose of this study was to examine the influence of occupational activities during pregnancy on maternal and fetal health outcomes.

STUDY

Studies of all designs (except case studies and reviews) that contained information on the relevant population (women who engaged in paid work during pregnancy), occupational exposures (heavy lifting, prolonged standing, prolonged walking, prolonged bending, and heavy physical workload), comparator (no exposure to the listed physical work demands), and outcomes (preterm birth, low birthweight, small for gestational age, miscarriage, gestational hypertension, preeclampsia, gestational diabetes mellitus, stillbirth, and intrauterine growth restriction) were included.

STUDY APPRAISAL AND SYNTHESIS METHODS

Five electronic databases and 3 gray literature sources were searched up to March 15, 2019.

RESULTS

Eighty observational studies (N=853,149) were included. Low-to-very low certainty evidence revealed that lifting objects ≥11 kg was associated with an increased odds ratio of miscarriage (odds ratio, 1.31; 95% confidence interval, 1.08-1.58; I²=79%), and preeclampsia (odds ratio, 1.35; 95% confidence interval, 1.07-1.71; I²=0%). Lifting objects for a combined weight of ≥100 kg per day was associated with an increased odds of preterm delivery (odds ratio, 1.31; 95% confidence interval, 1.11-1.56; I²=0%) and having a low birthweight neonate (odds ratio, 2.08; 95% confidence interval, 1.06-4.11; I²=73%). Prolonged standing was associated with increased odds of preterm delivery (odds ratio, 1.11; 95% confidence interval, 1.02-1.22; I²=30%) and having a small-for-gestational-age neonate (odds ratio, 1.17; 95% confidence interval, 1.01-1.35; I²=41%). A heavy physical workload was associated with increased odds of preterm delivery (odds ratio, 1.23; 95% confidence interval, 1.07-1.41; I²=32%) and having a low birthweight neonate (odds ratio, 1.79; 95% confidence interval, 1.11-2.87; I²=87%). All other associations were not statistically significant. Dose-response analysis showed women stand for >2.5 hours per day (vs no standing) had a 10% increase in the odds of having a preterm delivery.

CONCLUSION

Physically demanding work during pregnancy is associated with an increased risk of adverse pregnancy outcomes.

Doppler ultrasound and photoplethysmographic assessment for identifying pregnancy-induced hypertension

The current study investigated whether placentation and systemic inflammation are associated with pregnancy-induced hypertension (PIH) or pre-eclampsia (PE), and evaluated some measurable indexes for assessment of maternal factors contributing to high-risk pregnancy. Photoplethysmographic reflection index (PPG RI), uterine artery (UtA) pulsatile index (PI) and reflection index (RI), as well as maternal serum placental growth factor (PlGF) and soluble endoglin (sEng) were measured in pregnant women with singleton pregnancy at the gestational age of 22 to 23 weeks. Study subjects were women with normal pregnancy (NP, n=24), PIH (n=14) and PE (n=16). It was found that individuals in the PIH group exhibited higher UtA RI and UtA PI values, as well as PPG RI values compared with individuals in the NP group. Individuals in the PE group had the highest UtA RI, UtA PI and PPG RI values among these 3 groups. UtA and PPG results were significantly different in PIH and PE groups compared with the NP group. Significant differences were found in both PlGF and sEng levels between PIH and PE groups. A strong inverse across-subject correlation was found between PlGF and sEng levels. A weak inverse correlation was found between PlGF and UtA RI, and PlGF and UtA PI. A moderate inverse correlation was found between PlGF and PPG RI. A moderate positive correlation was found between either sEng and UtA RI or sEng and UtA PI. A very strong positive correlation was found between sEng and PPG RI. Taken together, the current results indicated that maternal effects related to cardiovascular adaptation to placentation and systemic inflammation exhibited significant differences between NP and PIH or PE groups. Therefore, assessment of UtA and PPG could be used for identifying high-risk pregnancy.

Review of Recent Physical Activity Guidelines During Pregnancy to Facilitate Advice by Health Care Providers

Importance

Physical activity during pregnancy can offer many maternal and fetal health benefits.

Objective

The aim was to summarize American, Canadian, and international recommendations published recently on physical activity during pregnancy to aid health care providers in their delivery of advice on the topic.

Evidence Acquisition

A descriptive review of 3 national guidelines and 1 international guideline on physical activity during pregnancy was conducted. The guidelines included the 2019 Canadian recommendations, the 2018 United States' Physical Activity Guidelines for Americans (second edition), the 2015 (reaffirmed in 2017) American College of Obstetrics and Gynecology guideline, and the 2016-2018 International Olympic Committee recommendations for recreational and elite athletes.

Results

For apparently healthy women, under the guidance of their health care provider, moderate-intensity physical activity using both aerobic and muscle conditioning activities is recommended. The guidelines recommended at least 150 min/wk spread throughout the week (Canada, United States) or at least 20 to 30 min/d (American College of Obstetrics and Gynecology).

Conclusions and Relevance

This summary of 4 recent guidelines can facilitate use of updated recommendations by health care providers regarding physical activity during pregnancy. More detailed evidence-based guidelines on physical activity during postpartum are needed.

Gestational Exercise and Maternal and Child Health: Effects until Delivery and at Post-Natal Follow-up

We studied the influence of pregnancy exercise on maternal/offspring cardiometabolic health until delivery and at follow-up. We pooled data from two randomized controlled trials from our group that were performed following the same methodology (one unpublished). We also collected follow-up data de novo from the participants of both trials and their offspring. In total, 1348 women with uncomplicated, singleton gestations were assigned to an intervention (n = 688, performing a supervised, moderate-intensity exercise program (three sessions/week)) or control group (n = 660). Maternal outcomes were excessive gestational weight gain (EGWG), gestational hypertension/diabetes and, at follow-up, return to pre-pregnancy weight within six months, hypertension, overweight/obesity, and other cardiometabolic conditions. Offspring outcomes were macrosomia and low-birthweight and, at follow-up, overweight/obesity, low-weight, and cardiometabolic conditions. Adherence to the intervention, which proved safe, was > 95%. Pregnancy exercise reduced the risk of EGWG, gestational hypertension, and diabetes (adjusted odds ratio (OR) and 95% confidence interval: 0.60 (0.46–0.79), 0.39 (0.23–0.67), and 0.48 (0.28–0.84)), and it was associated with a greater likelihood of returning to pre-pregnancy weight (2.37 (1.26–4.54)) and a lower risk of maternal cardiometabolic conditions (0.27 (0.08–0.95)) at the end of follow-up (median 6.1 years (interquartile range 1.8)). Pregnancy exercise also reduced the risk of macrosomia (0.36 (0.20–0.63)) and of childhood overweight/obesity during the first year (0.20 (0.06–0.63)). Our findings suggest that pregnancy exercise might protect maternal/offspring health.

How Can Maternal Lifestyle Interventions Modify the Effects of Gestational Diabetes in the Neonate and the Offspring? A Systematic Review of Meta-Analyses

Gestational diabetes (GDM) has deleterious effects on the offspring. Maternal obesity and excessive gestational weight gain (GWG), often associated with diabetes, also contribute to these adverse outcomes.

OBJECTIVES

To assess the benefit for the offspring of maternal lifestyle interventions, including diets and physical activity, to prevent or to improve GDM and to limit excessive GWG.

METHOD

Systematic review of meta-analyses published in English between December 2014 and November 2019.

RESULTS

Lifestyle interventions to reduce the risk of GDM reported a decreased risk of 15% to 40%, with a greater effect of exercise compared to diet. Combined lifestyle interventions specifically designed to limit GWG reduced GWG by 1.6 kg in overweight and obese women, and on average by 0.7 to 1 kg in all pregnant women. In these trials, adverse neonatal outcomes were poorly studied. Combined lifestyle interventions in women with GDM significantly reduced fetal growth. Altogether, lifestyle interventions reduced the risk of preterm birth and shoulder dystocia, but individually, diets or exercise alone had no effect on neonatal adverse outcomes.

CONCLUSION

Specific maternal, neonatal and offspring benefits of lifestyle interventions during pregnancy to prevent or improve GDM control or to limit GWG still require clarification.

Association of circulating saturated fatty acids with the risk of pregnancy-induced hypertension: a nested case-control study

Circulating saturated fatty acids (SFAs) have been associated with cardiovascular disease. However, little is known about the relationship of SFAs with the risk of pregnancy-induced hypertension (PIH). We conducted a nested case-control study to examine the associations between circulating SFAs and the risk of PIH. A total of 92 PIH cases were matched to 184 controls by age (±2 years) and infant sex from a birth cohort study conducted in Wuhan, China. Levels of circulating fatty acids in plasma were measured using gas chromatography-mass spectrometry. Conditional logistic regressions were conducted to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs). Even-chain SFAs, including myristic acid (14:0) and palmitic acid (16:0), were positively associated with the risk of PIH [ORs (95% CIs): 2.92 (1.27, 6.74) for 14:0 and 2.85 (1.18, 6.89) for 16:0, % by wt]. In contrast, higher levels of very-long-chain SFAs, including arachidic acid (20:0), behenic acid (22:0), and lignoceric acid (24:0), were associated with a lower risk of PIH [ORs (95% CIs): 0.40 (0.17, 0.92) for 20:0, 0.30 (0.12, 0.71) for 22:0 and 0.26 (0.11, 0.64) for 24:0, μg/mL]. For odd-chain SFAs, including pentadecanoic acid (15:0) and heptadecanoic acid (17:0), no significant difference was observed. Our results provided convincing evidence that different subclasses of SFAs showed diverse effects on the risk of PIH. This suggests that dietary very-long-chain SFAs may be a novel means by which to prevent hypertension. Future studies are required to confirm these associations and elucidate the underlying mechanisms.

Gestational Diabetes: Physical Activity Before Pregnancy and Its Influence on the Cardiovascular System

Objectives: Gestational diabetes mellitus (GDM) is a common complication in pregnancy, affecting around 14% of all pregnancies each year. It will likely further increase, as obesity becomes more prevalent. The impact of GDM on cardiovascular changes in pregnant women and her child is still unclear. The aim of the study was to measure the effects of physical activity before pregnancy on the cardiovascular system in patients with GDM in pregnancy. Methods: Two hundred and six pregnant women were included in this observational study. All participants were recruited at the tertiary level teaching University Hospital "Klinikum rechts der Isar" between 28 and 32 weeks gestation. Questionnaires dealing with pre-pregnancy daily and physical activity (PA) were evaluated. The cardiovascular status of the mothers included measurements of the intima-media thickness (IMT) of the carotid arteries. PA level was performed with a standardized 6-min-walking-test. Results: Ninety-nine women with GDM with a mean age of 33.84 (± 4.7) years were examined. One hundred seven healthy pregnant women aged 32.6 (± 4.2) years served as controls. The mean weight in the study group was 73.0 (± 20.3) kg and 61.7 (± 9.5) kg in the control group. Based on the higher weight in the study group, the Body Mass Index (BMI) was also significantly higher than in the control group (26.3 ± 7.1 vs. 21.6 ± 3; p < 0.001). The frequency of PA was significantly higher in the control group (p < 0.001). The objective fitness level was worse in pregnant women with GDM compared to healthy controls (472 vs. 523 m, p < 0.001). PA before and during pregnancy was less performed in the study group (86 vs. 64.5%, p = 0.002; 69 vs. 45.7%, p = 0.003). Women who were physically inactive before pregnancy had a 3-times higher risk to develop GDM compared to active women (OR = 2.67). The IMT was significantly thicker in the study group (0.48 ± 0.042 mm vs. 0.45 ± 0.042) mm; p = 0.006). Conclusion: Physical activity before pregnancy and a lower initial weight reduces the risk of developing GDM and cardiovascular risk factors in pregnancy. The development of prevention programs is certainly necessary.

Reproductive history, maternal anxiety and past physical activity practice predict physical activity levels throughout pregnancy

We compared physical activity (PA) levels between pregnant women who conceived naturally (NC) or after fertility treatments (FT) and determined factors predicting prenatal moderate-to-vigorous intensity physical activity (MVPA).

The study was conducted in Trois-Rivières (Canada) between October 2015 and July 2018. MVPA and anxiety levels were assessed at each trimester of pregnancy (TR1, TR2 and TR3) using an accelerometer and the State-Trait Anxiety Inventory, respectively. Sociodemographic and reproductive history data were self-reported or collected from medical files. Repeated measures analysis of variance and regression analyses were conducted.

Ninety-six women were included in the analyses (58 NC and 38 FT). MVPA levels and daily step counts decreased significantly throughout pregnancy (time effect: F = 28.68, p < 0.0001 and F = 39.18, p < 0.0001, respectively), but NC and FT women presented similar MVPA and daily step counts (no group effect). The decline in PA practice throughout pregnancy was similar in both groups (no interaction effect). At TR1, State (β = −0.272, p = 0.012) and Trait (β = −0.349, p = 0.001) anxiety and past PA (β = 0.483, p < 0.0001) were correlated with MVPA. Past MVPA was also correlated with MVPA at TR2 (β = 0.595, p < 0.0001) and TR3 (β = 0.654, p < 0.0001). Past PA was the strongest predictors of MVPA levels at TR1, TR2, and TR3, predicting 17% (p = 0.0002), 34% (p < 0.0001) and 42% (p < 0.0001), respectively. Overall, our findings suggest that MVPA practice throughout pregnancy is built on past PA practice. Therefore, to be effective at promoting PA throughout pregnancy, obstetric health care providers and fitness professionals should reinforce the importance of being active as early as possible during pregnancy.

CE: Gestational Hypertension, Preeclampsia, and Peripartum Cardiomyopathy: A Clinical Review

Gestational hypertension, preeclampsia, and peripartum cardiomyopathy are among the most common and often severe pregnancy-specific cardiovascular diseases (CVDs) and causes of complications in pregnancy. This clinical review provides nurses with an overview of pregnancy-specific CVDs, outlines their pathophysiology, and discusses risk factors and assessment. It describes management interventions according to timing: the antepartum, intrapartum, and postpartum phases are each addressed.

Examination of the Myokine Response in Pregnant and Non-pregnant Women Following an Acute Bout of Moderate-Intensity Walking

Background

It is recommended that women accumulate 150-min of weekly moderate-intensity physical activity (MPA) when pregnant. Engaging in regular physical activity (PA) confers many health benefits to both the mother and the fetus. However, the molecular mechanisms by which these health benefits are bestowed are not well understood. One potential factor that may be contributing to the observed benefits is myokines, which are small peptides secreted by skeletal muscles. In the non-pregnant population, myokines are believed to be involved in the molecular mechanisms resulting from PA. The objective of this study was to characterize and compare the myokine profile of pregnant and non-pregnant women, after an acute bout of MPA.

Methods

Pregnant (n = 13) and non-pregnant (n = 17) women were recruited from the Ottawa region to undergo a treadmill walking session at moderate-intensity (40–60% heart rate reserve). Pre- and post-exercise serum samples were taken, and a set of 15 myokines were analyzed although only 10 were detected. IL-6 was analyzed using a high-sensitivity assay, while FGF21, EPO, BDNF, Fractalkine, IL-15, SPARC, FABP-3, FSTL-1, and oncostatin were analyzed using various multiplex assays.

Results

The pregnant and non-pregnant groups did not differ in terms of age, height, non/pre-pregnancy weight, BMI, and resting heart rate. Baseline levels of EPO and oncostatin were higher in the pregnant group while FGF21 was higher in the non-pregnant group. Circulating levels of three myokines, FGF21, EPO, and IL-15 significantly increased in response to the acute exercise in the pregnant group. Non-pregnant women exhibited an increase in three myokines, FABP-3, FSTL-1, and oncostatin, while one myokine, EPO, decreased post-exercise. SPARC, fractalkine and BDNF were shown to increase post-exercise regardless of pregnancy status while the response for BDNF was more pronounced in the non-pregnant group.

Conclusion

This is the first study examining myokine response following an acute bout of PA in pregnancy. Moderate intensity PA, which is recommended during pregnancy, elicited an increase in four myokines post-compared to pre-exercise in the pregnant group. Further research is warranted to understand the role of myokines in pregnancy.

Physical Activity and Body Composition in Children and Their Mothers According to Mother's Gestational Diabetes Risk: A Seven-Year Follow-Up Study

Background and Objectives: There is lack of knowledge on whether mothers' gestational diabetes (GDM) risk is related to their physical activity (PA) or their children's PA and body composition. We aimed to examine the difference in (1) change in self-reported PA from pre-pregnancy to seven-year follow-up and (2) accelerometer-based PA at seven years after delivery between the mothers having GDM risk (GDMRyes-mothers) and not having GDM risk (GDMRno-mothers). Furthermore, we examined the difference in children's PA and/or body composition at six years of age according to their mothers' GDM risk. Materials and Methods: The study included 199 Finnish women. GDM risk factors were screened at the beginning of pregnancy, and the women were classified as GDMRyes-mothers if they had at least one GDM risk factor (body mass index ≥25 kg/m²; age ≥40 years; family history of diabetes; GDM, signs of glucose intolerance, or newborn's macrosomia (≥4500 g) in earlier pregnancy) or as GDMRno-mothers if they had no risk factors. Mothers' PA was assessed by self-reporting at 8-12 gestational weeks concerning pre-pregnancy PA and at a follow-up seven years after the delivery. Moreover, mothers' and their children's PA was measured using a triaxial Hookie AM20-accelerometer at seven years after delivery. Children's body composition was assessed using a TANITA bioelectrical impedance device. Adjusted linear regression analyses were applied. Results: GDMRno-mothers increased their self-reported PA more than GDMRyes-mothers from pre-pregnancy to the seven-year follow-up. Concerning women's measured PA as well as children's PA and body composition at seven years after delivery, the differences were non-significant between GDMRyes-mothers and GDMRno-mothers. However, of the GDM risk factors, mothers' pre-pregnancy body mass index was positively related to unhealthier body composition in boys at six years of age. Conclusion: Health promotion should be targeted at women with GDM risk factors, in particular overweight women, in enhancing women's PA in the long term and their children's healthy body composition.

Effects of physical exercise during pregnancy on mothers' and neonates' health: a protocol for an umbrella review of systematic reviews and meta-analysis of randomised controlled trials

INTRODUCTION

A growing interest has emerged on the effects of exercise during gestation. Several systematic reviews and meta-analyses have shown that prenatal exercise could reduce the mothers' risk for some disorders. Despite this, evidence regarding the risk of caesarean section, birth weight or Apgar score at delivery is still controversial. Furthermore, practitioners are reluctant to recommend exercise to pregnant women suffering from some disorders, such as hypertension, pre-eclampsia or pregnant women with obesity. Moreover, the scarcity of studies addressing the risks and benefits of exercise at higher intensity prevent practitioners from recommending it at higher dosages. Umbrella reviews represent an appropriate design to elucidate the reasons behind the contradictory findings of previous systematic reviews.

METHODS

This protocol was developed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols and the Cochrane Collaboration Handbook. Medline, EMBASE, Web of Science, Cochrane database of systematic reviews, Epistemonikos, Prospero register and SPORTDiscuss databases will be searched to identify systematic reviews, meta-analyses and randomised controlled trials that examine the effect of exercise on pregnancy outcomes from inception to August 2019. Searches will be conducted from September to November 2019.

STATISTICAL ANALYSIS

Methodological quality will be evaluated using the AMSTAR 2 tool. The certainty of evidence and strength of recommendations for meta-analyses will be assessed by the Grading of Recommendations Assessment, Development and Evaluation framework. The summary effect sizes will be calculated through the use of random-effects and fixed-effects models. Heterogeneity among studies will be assessed using the I2 statistic, and evidence of excess significance bias and evidence of small study effects will also be evaluated.

ETHICS AND DISSEMINATION

Ethical approval will not be needed for this review protocol. The results will be disseminated to academic audiences by peer-reviewed publications. Furthermore, results will be disseminated to clinical audiences through professionals' associations and social networks, and may influence guidelines developers in order to improve outcomes in mothers and offspring.

PROSPERO REGISTRATION NUMBER

CRD42019123410.

Exercise in Pregnant Women with Diabetes

PURPOSE OF REVIEW

Diabetes affects an increasing number of pregnancies. Regular exercise is recommended for pregnant women without diabetes, but whether exercise during pregnancy also benefits women with gestational diabetes (GDM) or preexisting (type 1 or type 2) diabetes or if these women have any specific risks is unclear.

RECENT FINDINGS

Recent evidence suggests that low- to moderate-intensity exercise improves blood glucose and may delay insulin initiation for women with GDM. Exercise is also safe, with no reports of increased maternal or neonatal complications. Few studies evaluated exercise as adjunct therapy for pregnant women with preexisting diabetes, precluding a thorough assessment in this population. Low- to moderate-intensity exercise during pregnancy safely improves glycemic control among women with GDM. More studies are needed to evaluate the impact of exercise in pregnant women with preexisting diabetes. Whether a specific type, volume, or timing of activity is most effective is not known.

National Analysis of Risk Assessment Content in Prenatal Records Across Canada

Each Canadian province/territory has a distinct prenatal record form to guide maternity health care. Because there is no national oversight of these forms, little is known about how they compare regarding content on risk assessment for adverse perinatal outcomes. We cataloged and compared the risk factors that are captured on prenatal record forms across Canada. Nine out of 12 records included risk sections, with an average of 35 risk items. We identified 100 prenatal risk factors and categorized them as medical (73%), lifestyle (11%), psychosocial (11%), or personal (5%). Where present, clinical definitions for risk factors often varied. The substantial differences in risk assessment content in the prenatal record forms may contribute to differences in health care quality among provinces. The development of standardized national guidelines for prenatal risk assessment may be a valuable goal.

The Association Between the rs2975760 and rs3792267 Single Nucleotide Polymorphisms of Calpain 10 (CAPN10) and Gestational Diabetes Mellitus

Background

This study aimed to investigate the association between the rs2975760 and rs3792267 single nucleotide polymorphisms (SNPs) of the calpain 10 (CAPN10) gene and gestational diabetes mellitus.

Material/Methods

The study included 138 patients with gestational diabetes mellitus and 152 healthy pregnant women. Venous blood was separated, and the DNA was extracted. The rs2975760 and rs3792267SNP polymorphisms of CAPN10 were detected using polymerase chain reaction (PCR). The frequencies of different genotypes in patients with gestational diabetes mellitus and healthy pregnant women were determined, and the relationship between different SNP genotypes and the risk of gestational diabetes mellitus was analyzed.

Results

There were no significant differences in the frequencies of the TT, CT and CC genotypes of rs2975760 and the frequencies of the GG, AG and AA genotypes of rs3792267 between the women with gestational diabetes and the controls. Expression of rs2975760 and rs3792267 were not associated with the risk of gestational diabetes in the dominant model, recessive model, and additive model. However, grade B and grade D diabetes in the CC and TC genotypes of rs2975760 were significantly different from those in the TT genotype (P<0.05). Grade B and grade D diabetes in the AA and AG genotypes of rs3792267 were significantly different compared with those in the GG genotype (P<0.05), and allele A was significantly increased compared with allele G (P<0.05).

Conclusions

The rs2975760 and rs3792267 SNP polymorphisms of CAPN10 showed no significant association with the incidence of gestational diabetes mellitus and only a mild association with the severity.

Risk factors for gestational diabetes: An umbrella review of meta-analyses of observational studies

BACKGROUND/OBJECTIVE

Gestational diabetes mellitus (GDM) is a common pregnancy complication, with complex disease mechanisms, and several risk factors may contribute to its onset. We performed an umbrella review to summarize the evidence from meta-analyses of observational studies on risk factors associated with GDM, evaluate whether there are indications of biases in this literature and identify which of the previously reported associations are supported by convincing evidence.

METHODS

We searched PubMed and ISI Web of Science from inception to December 2018 to identify meta-analyses examining associations between putative risk factors for GDM. For each meta-analysis we estimated the summary effect size, the 95% confidence interval, the 95% prediction interval, the between-study heterogeneity, evidence of small-study effects, and evidence of excess-significance bias.

RESULTS

Thirty eligible meta-analyses were identified, providing data on 61 associations. Fifty (82%) associations had nominally statistically significant findings (P<0.05), while only 15 (25%) were significant at P<10-6 under the random-effects model. Only four risk factors presented convincing evidence:, low vs. normal BMI (cohort studies), BMI ~30-35 kg/m2 vs. normal BMI, BMI >35 kg/m2 vs. normal BMI, and hypothyroidism.

CONCLUSIONS

The compilation of results from synthesis of observational studies suggests that increased BMI and hypothyroidism show the strongest consistent evidence for an association with GDM. Diet and lifestyle modifications in pregnancy should be tested in large randomized trials. Our findings suggest that women with known thyroid disease may be offered screening for GDM earlier in pregnancy.

Development and validation of a clinical model for preconception and early pregnancy risk prediction of gestational diabetes mellitus in nulliparous women

Implementation of dietary and lifestyle interventions prior to and early in pregnancy in high risk women has been shown to reduce the risk of gestational diabetes mellitus (GDM) development later in pregnancy. Although numerous risk factors for GDM have been identified, the ability to accurately identify women before or early in pregnancy who could benefit most from these interventions remains limited. As nulliparous women are an under-screened population with risk profiles that differ from their multiparous counterparts, development of a prediction model tailored to nulliparous women may facilitate timely preventive intervention and improve maternal and infant outcomes. We aimed to develop and validate a model for preconception and early pregnancy prediction of gestational diabetes mellitus based on clinical risk factors for nulliparous women. A risk prediction model was built within a large California birth cohort including singleton live birth records from 2007-2012. Model accuracy was assessed both internally and externally, within a cohort of women who delivered at University of Iowa Hospitals and Clinics between 2009-2017, using discrimination and calibration. Differences in predictive accuracy of the model were assessed within specific racial/ethnic groups. The prediction model included five risk factors: race/ethnicity, age at delivery, pre-pregnancy body mass index, family history of diabetes, and pre-existing hypertension. The area under the curve (AUC) for the California internal validation cohort was 0.732 (95% confidence interval (CI) 0.728, 0.735), and 0.710 (95% CI 0.672, 0.749) for the Iowa external validation cohort. The model performed particularly well in Hispanic (AUC 0.739) and Black women (AUC 0.719). Our findings suggest that estimation of a woman's risk for GDM through model-based incorporation of risk factors accurately identifies those at high risk (i.e., predicted risk >6%) who could benefit from preventive intervention encouraging prompt incorporation of this tool into preconception and prenatal care.