2019 Canadian Guideline for Physical Activity Throughout Pregnancy: Methodology

Metabolomics to Understand Alterations Induced by Physical Activity during Pregnancy

Physical activity (PA) and exercise have been associated with a reduced risk of cancer, obesity, and diabetes. In the context of pregnancy, maintaining an active lifestyle has been shown to decrease gestational weight gain (GWG) and lower the risk of gestational diabetes mellitus (GDM), hypertension, and macrosomia in offspring. The main pathways activated by PA include BCAAs, lipids, and bile acid metabolism, thereby improving insulin resistance in pregnant individuals. Despite these known benefits, the underlying metabolites and biological mechanisms affected by PA remain poorly understood, highlighting the need for further investigation. Metabolomics, a comprehensive study of metabolite classes, offers valuable insights into the widespread metabolic changes induced by PA. This narrative review focuses on PA metabolomics research using different analytical platforms to analyze pregnant individuals. Existing studies support the hypothesis that exercise behaviour can influence the metabolism of different populations, including pregnant individuals and their offspring. While PA has shown considerable promise in maintaining metabolic health in non-pregnant populations, our comprehension of metabolic changes in the context of a healthy pregnancy remains limited. As a result, further investigation is necessary to clarify the metabolic impact of PA within this unique group, often excluded from physiological research.

The Influence of Exercise-Associated Small Extracellular Vesicles on Trophoblasts In Vitro

Exercise induces the release of small extracellular vesicles (sEVs) into circulation that are postulated to mediate tissue cross-talk during exercise. We previously reported that pregnant individuals released greater levels of sEVs into circulation after exercise compared to matched non-pregnant controls, but their biological functions remain unknown. In this study, sEVs isolated from the plasma of healthy pregnant and non-pregnant participants after a single bout of moderate-intensity exercise were evaluated for their impact on trophoblasts in vitro. Exercise-associated sEVs were found localized within the cytoplasm of BeWo choriocarcinoma cells, used to model trophoblasts in vitro. Exposure to exercise-associated sEVs did not significantly alter BeWo cell proliferation, gene expression of angiogenic growth factors VEGF and PLGF, or the release of the hormone human chorionic gonadotropin. The results from this pilot study support that exercise-associated sEVs could interact with trophoblasts in vitro, and warrant further investigation to reveal their potential role in communicating the effects of exercise to the maternal–fetal interface.

Impact of acute moderate-intensity aerobic exercise on circulating extracellular vesicles in pregnant and non-pregnant women

Exercise improves cardiovascular and metabolic health in pregnancy and may represent a non-pharmacological approach to improving pregnancy outcomes. Extracellular vesicles (EVs) are emerging biomarkers of endothelial dysfunction and offer the potential for evaluating vascular health non-invasively during pregnancy. The purpose of this study was to investigate changes in circulating EV levels after an acute bout of moderate-intensity aerobic exercise in healthy pregnant and non-pregnant women. We studied plasma samples from pregnant (N = 13, 13-28 weeks) and non-pregnant (N = 17) women. A pre-exercise blood sample was obtained followed by a 30 min bout of moderate-intensity treadmill-based exercise. Immediately following the exercise, a post-exercise blood draw was collected. Large EVs were isolated from plasma by differential centrifugation and characterized by Western blot and electron microscopy. We quantified circulating EVs by nanoscale flow cytometry. Endothelial EVs were identified as VE-Cadherin+, platelet EVs as CD41+, and leukocyte EVs as CD45+ events. Acute exercise was associated with a significant reduction in levels of circulating endothelial EVs in the non-pregnant group (p = 0.0232) but not in the pregnant group (p = 0.2734). A greater proportion of non-pregnant women (13/17, 76.47%) exhibited a reduction in endothelial EVs compared with their pregnant counterparts (4/13, 30.76%, p < 0.05). We also observed a positive association between measures of fitness (average speed) and baseline levels of platelet (r = 0.5816, p = 0.0159) and total EVs (r = 0.5325, p = 0.0296) in the non-pregnant group but not in pregnant individuals. Collectively, our study highlights that after a matched acute exercise, changes to circulating EV levels differ depending on pregnancy status.

Development of the Get Active Questionnaire for Pregnancy: Breaking down barriers to prenatal exercise

Evidence-based guidelines represent the highest level of scientific evidence to identify best-practices for clinical/public health. However, the availability of guidelines do not guarantee their use, targeted knowledge translation strategies and tools are necessary to help promote uptake. Following publication of the 2019 Canadian Guideline for Physical Activity throughout Pregnancy, the Get Active Questionnaire for Pregnancy, and an associated Health Care Provider Consultation Form for Prenatal Physical Activity were developed to promote guideline adoption and use amongst pregnant individuals and health care providers. This paper describes the process of developing these tools. First, a survey was administered to qualified exercise professionals to identify the barriers and facilitators in using existing prenatal exercise screening tools. A Working Group of researchers and stakeholders then convened to develop an evidence-informed exercise pre-participation screening tool for pregnant individuals, building from previous tool and survey findings. Finally, end-user feedback was solicited through a survey and key informant interviews to ensure tools are feasible and acceptable to use in practice. The uptake and use of these documents by pregnant individuals, exercise and health care professionals will be assessed in future studies. Novelty Bullets • Evidence supports the safety/benefits of exercise for most pregnant individuals; however, exercise is not recommended for a small number of individuals with specific medical conditions. • The Get Active Questionnaire for Pregnancy and Health Care Provider Consultation Form for Physical Activity during Pregnancy identify individuals where prenatal exercise may pose a risk, while reducing barriers to physical activity participation for the majority of pregnant individuals.

Be Healthy in Pregnancy (BHIP): A Randomized Controlled Trial of Nutrition and Exercise Intervention from Early Pregnancy to Achieve Recommended Gestational Weight Gain

A randomized two-arm prospective superiority trial tested the efficacy of a novel structured and monitored nutrition (bi-weekly counselling for individualized energy and high dairy protein diet) and exercise program (walking goal of 10,000 steps/day) (intervention) compared to usual care (control) in pregnant women to achieve gestational weight gain (GWG) within current recommendations. Women recruited in communities in southern Ontario, Canada were randomized at 12–17 weeks gestation with stratification by site and pre-pregnancy BMI to intervention (n = 119) or control (n = 122). The primary outcome was the proportion of women who achieved GWG within the Institute of Medicine recommendations. Although the intervention compared to control group was more likely to achieve GWG within recommendations (OR = 1.51; 95% CI (0.81, 2.80)) and total GWG was lower by 1.45 kg (95% CI: (−11.9, 8.88)) neither reached statistical significance. The intervention group achieved significantly higher protein intake at 26–28 week (mean difference (MD); 15.0 g/day; 95% CI (8.1, 21.9)) and 36–38 week gestation (MD = 15.2 g/day; 95% CI (9.4, 21.1)) and higher healthy diet scores (22.5 ± 6.9 vs. 18.7 ± 8.5, p < 0.005) but step counts were similar averaging 6335 steps/day. Pregnancy and infant birth outcomes were similar between groups. While the structured and monitored nutrition with counselling improved diet quality and protein intake and may have benefited GWG, the exercise goal of 10,000 steps/day was unachievable. The results can inform future recommendations for diet and physical activity in pregnancy.

Weight stigma and prenatal physical activity: Exploring the perspectives of pregnant women living with obesity

OBJECTIVE

To identify sources of weight stigma in physical activity (PA)-related milieus reported by pregnant women living with obesity. We also report person-informed strategies to improve the delivery of PA promotions and prescriptions to prevent weight stigma and improve maternal PA.

DESIGN

This is a qualitative descriptive study and semi-structured interviews were conducted.

SETTING AND PARTICIPANTS

Purposive sampling including pregnant women living with obesity, with a body mass index ≥35.0 kg/m², ≥18 years of age, and receiving specialized prenatal care were recruited from an obstetrics clinic in Kingston, Canada.

MEASUREMENT AND FINDINGS

Data were assessed by a content analysis, whereby coded themes represented sources of weight stigma related to prenatal PA. Demographic characteristics (pre-pregnancy body mass index, age, gestational age) were summarized and presented as means and standard deviations. In-depth interview data were collected from eight women. Average pre-pregnancy BMI, age, and gestational age were 44.6±4.8 kg/m², 32.0±4.1 years, 31.1±5.8 weeks, respectively. Two sources of weight stigma related to prenatal PA were identified: 1. Lack of visual representation - online images and images found in exercise promotional material do not include women who have obesity; 2. Lack of individualized recommendations - currently available prenatal PA guidelines and/or recommendations from healthcare providers do not always consider individual physical barriers or health goals women may have.

KEY CONCLUSION AND IMPLICATIONS FOR PRACTICE

By increasing body positive representation of pregnant women exercising and offering person-centered prenatal PA recommendations, maternal PA may improve including women living with obesity. Findings from this work can inform future PA interventions, health promotion programming, and prescriptions from prenatal care providers to implement person-oriented strategies to prevent weight stigma and improve the delivery of care for pregnant women living with obesity.

Heat loss responses at rest and during exercise in pregnancy: A scoping review

BACKGROUND

The teratogenic risk associated with maternal hyperthermia (i.e., core temperature ≥39.0 °C) has been a crucial motive in understanding thermoregulatory responses in pregnancy. To date, a substantial number of studies have focused on core temperature responses in a wide range of exercise intensities, duration, and ambient temperatures. Fortunately, none have reported core temperatures exceeding 39.0 °C. Nonetheless, there are limited studies that have provided substantial insight into both dry and evaporative heat loss mechanisms involved in facilitating the maintenance of core temperature (≥39.0 °C) during heat stress in pregnant women. The purpose of this scoping review was to summarize the available literature that has assessed heat loss responses in studies of human pregnancy.

METHODS

A search strategy was developed combining the terms pregnancy, thermoregulation, and adaptation. A systematic search was performed in the following databases: PubMed, Embase, Scopus, and ProQuest. Studies eligible for inclusion included pregnant women between the ages of 18-40 years old, and at least one measurement of the following: sweating, blood flow, skin temperature, and behavioural responses. Retrieved data were categorized as evaporative (sweating), dry or behavioural heat loss responses and summarized narratively.

RESULTS

Thirty-three studies were included in this review (twenty-nine measured physiological responses and four measured behavioural responses). Studies suggest that during exercise, evaporative (sweating) and dry (skin blood flow and temperature) heat loss responses increase from early to late pregnancy in addition to greater cardiac output, blood volume and reduced vascular resistance. Behavioural practices related to heat loss responses are also influenced by cultural/religious expectations, personal preferences and sociodemographics.

CONCLUSION

The findings from this review suggest that pregnancy modifies evaporative (sweating), dry and behavioural heat loss. However, future studies have an opportunity to compare heat loss measurements accounting for gestational weight gain and thermal sensation/comfort scale to associate physiological responses with perceptual responses across pregnancy.

Optimizing women's cardiovascular health after hypertensive disorders of pregnancy: a translational approach to cardiovascular disease prevention

Women who experience a hypertensive disorder of pregnancy (HDP) are amongst those at the highest risk of premature cardiovascular diseases (CVD). In Canada, effective CVD prevention interventions tailored specifically for this high-risk population are urgently needed. The objective of this review is to summarize a broad range of mechanistic and clinical studies examining the association of HDP with future CVD to inform postpartum clinical follow-up strategies focused on improving women's cardiovascular health. The current state of the science (animal model, observational and intervention studies) largely support two main hypotheses explaining the epidemiological link between HDP and long-term risk of CVD. First, that the complicated pregnancy "unmasks" women who were predisposed to CVD prior to pregnancy (i.e., women with subclinical atherosclerosis or pre-pregnancy CVD risk factors). Second, that HDP causes vascular dysfunction and/or worsens preexisting, subclinical CVD risk factors. Despite this strong evidence, several knowledge gaps remain in the understanding of specific mechanisms linking these two theories and the impacts of other important contributors (e.g., intersectional factors). From a clinical perspective, given the consistent data demonstrating a high prevalence of CVD risk factors after HDP, routine care after pregnancy at minimum should include: 1) standardized assessment of pregnancy-associated CV risks (P-CVRs); 2) early and regular screening of traditional CVD risk factors; 3) education and support for health behaviours as first line therapy (including breastfeeding); 4) individualized pharmacotherapy (i.e., statins, antihypertensives or antiglycemic agents as clinically indicated); and 5) consideration of a woman's health goals, reproductive plans and social context.

Circulating small extracellular vesicles increase after an acute bout of moderate-intensity exercise in pregnant compared to non-pregnant women

The physiological and molecular mechanisms linking prenatal physical activity and improvements in maternal–fetal health are unknown. It is hypothesized that small extracellular vesicles (EVs, ~ 10–120 nm) are involved in tissue cross-talk during exercise. We aimed to characterize the circulating small EV profile of pregnant versus non-pregnant women after an acute bout of moderate-intensity exercise. Pregnant (N = 10) and non-pregnant control (N = 9) women performed a single session of moderate-intensity treadmill walking for 30 min. Plasma was collected immediately pre- and post-exercise, and small EVs were isolated by differential ultracentrifugation. EV presence was confirmed by western blotting for the small EV proteins TSG-101 and flottilin-1. Small EVs were quantified by size and concentration using nanoparticle tracking analysis and transmission electron microscopy. All EV fractions were positive for TSG-101 and flotillin-1, and negative for calnexin. Mean vesicle size at baseline and percent change in size post-exercise were not different between groups. At baseline, pregnant women had higher levels of small EVs compared to controls (1.83E+10 ± 1.25E+10 particles/mL vs. 8.11E+09 ± 4.04E+09 particles/mL, respectively; p = 0.032). Post-exercise, small EVs increased significantly in the circulation of pregnant compared to non-pregnant women after correcting for baseline values (64.7 ± 24.6% vs. − 23.3 ± 26.1%, respectively; F = 5.305, p = 0.035). Further research is needed to assess the functional roles of exercise-induced small EVs in pregnancy.

Maternal swimming mitigates liver damage caused by paternal obesity

OBJECTIVES

Parents' lifestyle and nutrition can program offspring obesity in adulthood. We hypothesized that maternal swimming has beneficial effects on the adversity caused by paternal obesity on offspring.

METHODS

Twelve-week-old male C57 BL/6 J mice (fed a high-fat diet, obese father [ObFa], or control diet, lean father [LFa]) were mated with female mice fed only the control diet. Mothers were trained (TMo) or untrained (UMo): swimming for 6 wk before and the first 2 wk of gestation. Pups were fed only the control diet.

RESULTS

Fathers showed different body mass (BM) at copulation, but not the mothers. The ObFa had 20% higher BM than the LFa. Twelve-week-old ObFa/UMo offspring showed a higher BM gain than the LFa/UMo and ObFa/TMo. There was BM sexual dimorphism in the LFa/UMo (female mice +24% than male mice). There was hyperglycemia and hyperinsulinemia in the ObFa/UMo, but low glycemia and insulin levels were seen in the ObFa/TMo. There was augmented liver steatosis in the ObFa/UMo compared with the LFa/UMo, and the ObFa/TMo compared with the LFa/TMo, but reduced steatosis in the ObFa/TMo compared with the ObFa/UMo. In addition, lipogenic markers were more expressed and beta-oxidation markers less expressed in the ObFa/UMo compared with the LFa/UMo, but the opposite was observed in the ObFa/TMo compared with the ObFa/UMo. Proinflammatory markers were higher in the liver of the ObFa/UMo compared with the LFa/UMo and lower in the ObFa/TMo compared with the ObFa/UMo.

CONCLUSIONS

Obese fathers produced offspring that were overweight and had altered fasting glycemia and insulin sensitivity, leading to higher liver lipogenesis and inflammation, as well as lower beta-oxidation. The swimming mother mitigated these adverse effects in mice offspring.

Association Between Physical Activity, Weight Loss, Anxiety, and Lumbopelvic Pain in Postpartum Women

OBJECTIVE

Lumbopelvic pain (LBPP) affects 45% to 81% of pregnant women, and 25% to 43% of these women report persistent LBPP beyond 3 months after giving birth. The objective of this study was to investigate the association of physical activity, weight status, anxiety, and evolution of LBPP symptoms in postpartum women.

METHODS

This was a prospective observational cohort study with 3 time-point assessments: baseline (T0), 3 months (T3), and 6 months (T6). Women with persistent LBPP 3 to 12 months after delivery were recruited. At each time point, pain disability was assessed with the Pelvic Girdle Questionnaire and the Oswestry Disability Index (ODI), physical activity with Fitbit Flex monitors, and anxiety with the French-Canadian version of the State-Trait Anxiety Inventory. Weight was recorded using a standardized method. Pain intensity (numerical rating scale, 0-100) and frequency were assessed using a standardized text message on a weekly basis throughout the study.

RESULTS

Thirty-two women were included (time postpartum: 6.6 ± 2.0 months; maternal age: 28.3 ± 3.8 years; body weight: 72.9 ± 19.1 kg), and 27 completed the T6 follow-up. Disability, pain intensity, and pain frequency improved at T6 (P < .001). Participants lost a mean of 1.9 ± 4.5 kg at T6, and this weight loss was correlated with reduction in LBPP intensity (r = 0.479, P = .011) and LBPP frequency (r = 0.386, P = .047), Pelvic Girdle Questionnaire score (r = 0.554, P = .003), and ODI score (r = 0.494, P = .009). Improvement in ODI score at T6 was correlated with the number of inactive minutes at T3 (r = -0.453, P = .026) and T6 (r = -0.457, P = .019), and with daily steps at T6 (r = 0.512, P = .006).

CONCLUSION

Weight loss is associated with positive LBPP symptom evolution beyond 3 months postpartum, and physical activity is associated with reduction in pain disability.

Moms Are Not OK: COVID-19 and Maternal Mental Health

Introduction: Depression and anxiety affect one in seven women during the perinatal period, and are associated with increased risk of preterm delivery, reduced mother-infant bonding, and delays in cognitive/emotional development of the infant. With this survey we aimed to rapidly assess the influence of the COVID-19 pandemic and subsequent physical distancing/isolation measures on the mental health and physical activity of pregnant and postpartum women.

Methods: Between April 14 and May 8, 2020, we recruited women who were pregnant or within the first year after delivery to participate in an online survey. This included questionnaires on self-reported levels of depression/depressive symptoms (Edinburgh Postnatal Depression Survey; EPDS), anxiety (State-Trait Anxiety Inventory; STAI-State), and physical activity. Current and pre-pandemic values were assessed for each.

Results: Of 900 eligible women, 520 (58%) were pregnant and 380 (42%) were in the first year after delivery. Sixty-four percent of women reported reduced physical activity with the onset of isolation measures, while 15% increased, and 21% had no change to their physical activity. An EPDS score >13 (indicative of depression) was self-identified in 15% of respondents pre-pandemic and in 40.7% currently (mean ± SD; 7.5 ± 4.9 vs. 11.2 ± 6.3, respectively; p < 0.01, moderate effect). Moderate to high anxiety (STAI-state score >40) was identified in 29% of women before the pandemic (mean STAI = 34.5 ± 11.4) vs. 72% of women currently (mean STAI = 48.1 ± 13.6; p < 0.01, large effect). However, women engaging in at least 150 min of moderate intensity physical activity (meeting current guidelines) during the pandemic had significantly lower scores for both anxiety and depression than those who did not (p < 0.01, large and small effect, respectively).

Discussion: This rapid response survey identifies a substantial increase in the likelihood of maternal depression and anxiety during the COVID-19 pandemic. This highlights the strong need for heightened assessment and treatment of maternal mental health. However, these data also suggest that physical activity, which has previously been shown to reduce depression and depressive symptoms in pregnancy, may be associated with better mental health during the pandemic.

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.

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.

Energy Intake Requirements in Pregnancy

Energy intake requirements in pregnancy match the demands of resting metabolism, physical activity, and tissue growth. Energy balance in pregnancy is, therefore, defined as energy intake equal to energy expenditure plus energy storage. A detailed understanding of these components and their changes throughout gestation can inform energy intake recommendations for minimizing the risk of poor pregnancy outcomes. Energy expenditure is the sum of resting and physical activity-related expenditure. Resting metabolic rate increases during pregnancy as a result of increased body mass, pregnancy-associated physiological changes, i.e., cardiac output, and the growing fetus. Physical activity is extremely variable between women and may change over the course of pregnancy. The requirement for energy storage depends on maternal pregravid body size. For optimal pregnancy outcomes, women with low body weight require more fat mass accumulation than women with obesity, who do not require to accumulate fat mass at all. Given the high energy density of fat mass, these differences affect energy intake requirements for a healthy pregnancy greatly. In contrast, the energy stored in fetal and placental tissues is comparable between all women and have small impact on energy requirements. Different prediction equations have been developed to quantify energy intake requirements and we provide a brief review of the strengths and weaknesses and discuss their application for healthy management of weight gain in pregnant women.

The Effects of Exercise on Pain and Reproductive Performance in Female Pregnant Mice With Neuropathic Pain

Pain can have negative, physiological and psychological impacts on pregnancy. Pregnant women are fearful of using pain medication because of teratogenic effects. In this study, we evaluated whether exercise could lower pain sensitivity in pregnant mice with neuropathic pain and reduce the negative effects of maternal pain on newborns. We randomly assigned 32 female mice to one of four groups (eight mice/group): Sham surgery with standard environment (SE) or enriched environment (EE) or spare nerve injury (SNI) with SE or EE. Mice in EE groups had access to an exercise wheel. Mothers were evaluated for mechanical sensitivity with Von Frey filaments and for exercise performance with computerized running wheels. Mice were impregnated 2 weeks after the initiation of EE. Pups were weighed and measured for length at birth and evaluated for negative geotaxis, righting, forelimb grasping, rooting, and crawling at 3 days postpartum and for crawling at 6 days postpartum. Following euthanasia, mothers' frontal cortexes were analyzed for selected neuropeptides. After exercise exposure, only SNI-SE females remained neuropathic. Exercise levels were similar between EE groups. Some brain neuropeptides (endorphins, enkephalins, and oxytocin) from SNI females showed significant differences with exercise. Number of pups was significantly smaller in the SNI-SE group. Significantly more pups died at birth in the SNI-SE group, but pup behavior tests (except righting) were similar across groups. Exercise can reduce neuropathic pain in pregnant mice. Neuropathic pain does not impact motor neurodevelopment of mice pups but does appear to affect litter size and neonatal mortality.

N° 367-2019 Lignes Directrices Canadiennes Sur L'activité Physique Durant La Grossesse

OBJECTIF

L'objectif est de guider les femmes enceintes et les professionnels de l'obstétrique et de l'exercice en ce qui concerne l'activité physique prénatale. RéSULTATS: Les issues évaluées étaient la morbidité maternelle, fœtale ou néonatale et la mortalité fœtale pendant et après la grossesse. DONNéES: Nous avons interrogé MEDLINE, Embase, PsycINFO, la Cochrane Database of Systematic Reviews, le Cochrane Central Register of Controlled Trials, Scopus et la Web of Science Core Collection, CINAHL Plus with Full Text, Child Development & Adolescent Studies, ERIC, SPORTDiscus, ClinicalTrials.gov de leur création jusqu'au 6 janvier 2017. Les études primaires de tous types étaient admissibles, à l'exception des études de cas. Seules les publications en anglais, en espagnol et en français ont été retenues. Les articles liés à l'activité physique durant la grossesse qui abordaient la morbidité maternelle, fœtale ou néonatale ou la mortalité fœtale étaient admissibles. La qualité des données probantes a été évaluée au moyen de l'approche GRADE (Grading of Recommendations Assessment, Development and Evaluation).

VALEURS

Le groupe d'experts responsable des lignes directrices a recueilli les commentaires d'utilisateurs finaux (fournisseurs de soins obstétricaux, professionnels de l'exercice, chercheurs, organismes responsables de politiques, et femmes enceintes et en période postpartum). La directive clinique a été élaborée au moyen de l'outil Appraisal of Guidelines for Research Evaluation (AGREE) II. AVANTAGES, INCONVéNIENTS, ET COûTS: Les avantages de l'activité physique prénatale sont modérés, et aucun inconvénient n'a été relevé; la différence entre les conséquences désirables et indésirables (avantage net) devrait donc être modérée. La majorité des intervenants et des utilisateurs finaux ont indiqué qu'il serait faisable, acceptable et équitable de suivre ces recommandations, qui nécessitent généralement des ressources minimes de la part des personnes et des systèmes de santé. PRÉAMBULE: Les présentes lignes directrices contiennent des recommandations fondées sur des données probantes au sujet de l'activité physique durant la grossesse visant à favoriser la santé maternelle, fœtale et néonatale. En l'absence de contre-indications (voir la liste détaillée plus loin), le fait de suivre ces lignes directrices est associé à : 1) moins de complications pour le nouveau-né (p. ex., gros par rapport à l'âge gestationnel); et 2) des bienfaits pour la santé maternelle (p. ex., diminution du risque de prééclampsie, d'hypertension gravidique, de diabète gestationnel, de césarienne, d'accouchement opératoire, d'incontinence urinaire, de gain de poids excessif durant la grossesse et de dépression; amélioration de la glycémie; diminution du gain de poids total durant la grossesse; et diminution de la gravité des symptômes dépressifs et de la douleur lombo-pelvienne). L'activité physique n'est pas associée à la fausse couche, à la mortinaissance, au décès néonatal, à l'accouchement prématuré, à la rupture prématurée préterme des membranes, à l'hypoglycémie néonatale, au poids insuffisant à la naissance, aux anomalies congénitales, au déclenchement du travail, ou aux complications à la naissance. En général, une augmentation de l'activité physique (fréquence, durée ou volume) est liée à une augmentation des bienfaits. Cependant, nous n'avons pas trouvé de données probantes concernant l'innocuité ou l'avantage accru de l'exercice à des niveaux considérablement supérieurs aux recommandations. L'activité physique prénatale devrait être vue comme un traitement de première ligne pour réduire le risque de complications de la grossesse et améliorer la santé physique et mentale de la mère. Pour les femmes enceintes qui n'atteignent actuellement pas le niveau recommandé, nous recommandons une augmentation progressive pour l'atteindre. Les femmes déjà actives peuvent continuer de l'être tout au long de la grossesse. Elles pourraient devoir modifier le type d'activité à mesure que leur grossesse avance. Il peut devenir impossible de suivre les lignes directrices pendant certaines périodes en raison de la fatigue ou des inconforts de la grossesse; nous encourageons les femmes à faire ce qu'elles peuvent et à revenir aux recommandations lorsqu'elles en sont capables. Les recommandations qui suivent reposent sur une revue systématique approfondie de la littérature, l'opinion d'experts, la consultation d'utilisateurs finaux et des considérations de faisabilité, d'acceptabilité, de coût et d'équité.

RECOMMANDATIONS

Les recommandations des Lignes directrices canadiennes sur l'activité physique durant la grossesse 2019 sont fournies ci-dessous avec des énoncés indiquant la qualité des données probantes utilisées et la force des recommandations (des explications suivent).

CONTRE-INDICATIONS

Toutes les femmes enceintes peuvent faire de l'activité physique durant la grossesse, sauf celles qui présentent des contre-indications (voir ci-dessous). Celles présentant des contre-indications absolues peuvent poursuivre leurs activités quotidiennes habituelles, mais ne devraient pas faire d'activités plus vigoureuses. Celles présentant des contre-indications relatives devraient discuter des avantages et des inconvénients de l'activité physique d'intensité modérée à vigoureuse avec leur fournisseur de soins obstétricaux avant d'y prendre part.

CONTRE-INDICATIONS ABSOLUES

Contre-indications relatives  FORCE DES RECOMMANDATIONS: Nous avons utilisé le système GRADE pour évaluer la force des recommandations. Les recommandations sont jugées fortes ou faibles en fonction de : 1) l'équilibre entre les avantages et les inconvénients; 2) la qualité globale des données probantes; 3) l'importance des issues (valeurs et préférences des femmes enceintes); 4) l'utilisation de ressources (coût); 5) l'incidence sur l'équité en matière de santé; 6) la faisabilité et 7) l'acceptabilité. Recommandation forte : La majorité ou la totalité des femmes enceintes auraient avantage à suivre la recommandation. Recommandation faible : Les femmes enceintes n'auraient pas toutes avantage à suivre la recommandation; il faut tenir compte d'autres facteurs comme la situation, les préférences, les valeurs, les ressources et le milieu de chaque personne. La consultation d'un fournisseur de soins obstétricaux peut faciliter la prise de décisions. QUALITé DES DONNéES PROBANTES: La qualité des données probantes fait référence au degré de confiance dans les données et va de très faible à élevée. Qualité élevée : Le groupe d'experts responsable des lignes directrices est très convaincu que l'effet estimé de l'activité physique sur l'issue de santé est près de l'effet réel. Qualité moyenne : Le groupe d'experts responsable des lignes directrices a moyennement confiance en l'effet estimé de l'activité physique sur l'issue de santé; l'effet estimé est probablement près de l'effet réel, mais il est possible qu'il soit très différent. Qualité faible : Le groupe d'experts responsable des lignes directrices a peu confiance en l'effet estimé de l'activité physique sur l'issue de santé; l'effet estimé pourrait être très différent de l'effet réel. Qualité très faible : Le groupe d'experts responsable des lignes directrices a très peu confiance en l'effet estimé de l'activité physique sur l'issue de santé; l'effet estimé est probablement très différent de l'effet réel. ^a Il s'agit d'une recommandation faible parce que la qualité des données probantes était faible et que l'avantage net entre les femmes qui étaient physiquement actives et celles qui ne l'étaient pas était petit. ^b Il s'agit d'une recommandation forte parce que, malgré le fait que les données probantes appuyant l'activité physique durant la grossesse pour les femmes en surpoids ou obèses étaient de qualité faible, des données tirées d'essais cliniques randomisés démontraient une diminution du gain de poids durant la grossesse et une amélioration de la glycémie. ^c On parle d'intensité modérée lorsque l'activité est assez intense pour augmenter la fréquence cardiaque de façon perceptible; une personne peut parler, mais pas chanter durant les activités de cette intensité. Pensons par exemple à la marche rapide, à la gymnastique aquatique, au vélo stationnaire (effort modéré), à l'entraînement musculaire, au port de charges modérées et aux travaux ménagers (p. ex., jardinage, lavage de fenêtres). ^d Il s'agit d'une recommandation faible parce que l'incontinence urinaire n'était pas jugée comme étant une issue « critique » et que les données étaient de qualité faible. ^e Il s'agit d'une recommandation faible parce que : 1) la qualité des données probantes était très faible; et 2) bien que nous ayons étudié les inconvénients, il y avait peu de renseignements disponibles sur l'équilibre entre les avantages et les inconvénients. Cette recommandation était principalement fondée sur l'opinion d'experts.

No. 367-2019 Canadian Guideline for Physical Activity throughout Pregnancy

OBJECTIVE

The objective is to provide guidance for pregnant women, and obstetric care and exercise professionals, on prenatal physical activity.

OUTCOMES

The outcomes evaluated were maternal, fetal, or neonatal morbidity or fetal mortality during and following pregnancy.

EVIDENCE

Literature was retrieved through searches of Medline, EMBASE, PsycINFO, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Scopus and Web of Science Core Collection, CINAHL Plus with Full-text, Child Development & Adolescent Studies, ERIC, Sport Discus, ClinicalTrials.gov, and the Trip Database from database inception up to January 6, 2017. Primary studies of any design were eligible, except case studies. Results were limited to English, Spanish, or French language materials. Articles related to maternal physical activity during pregnancy reporting on maternal, fetal, or neonatal morbidity or fetal mortality were eligible for inclusion. The quality of evidence was rated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology.

VALUES

The Guidelines Consensus Panel solicited feedback from end-users (obstetric care providers, exercise professionals, researchers, policy organizations, and pregnant and postpartum women). The development of this guideline followed the Appraisal of Guidelines for Research Evaluation (AGREE) II instrument.

BENEFITS, HARMS, AND COSTS

The benefits of prenatal physical activity are moderate, and no harms were identified; therefore, the difference between desirable and undesirable consequences (net benefit) is expected to be moderate. The majority of stakeholders and end-users indicated that following these recommendations would be feasible, acceptable, and equitable. Following these recommendations is likely to require minimal resources from both individual and health systems perspectives.

PREAMBLE

This guideline provide evidence-based recommendations regarding physical activity throughout pregnancy in the promotion of maternal, fetal, and neonatal health. In the absence of contraindications (see later for a detailed list), following this guideline is associated with: (1) fewer newborn complications (i.e., large for gestational age); and (2) maternal health benefits (i.e., decreased risk of preeclampsia, gestational hypertension, gestational diabetes, Caesarean section, instrumental delivery, urinary incontinence, excessive gestational weight gain, and depression; improved blood glucose; decreased total gestational weight gain; and decreased severity of depressive symptoms and lumbopelvic pain). Physical activity is not associated with miscarriage, stillbirth, neonatal death, preterm birth, preterm/prelabour rupture of membranes, neonatal hypoglycemia, low birth weight, birth defects, induction of labour, or birth complications. In general, more physical activity (frequency, duration, and/or volume) is associated with greater benefits. However, evidence was not identified regarding the safety or additional benefit of exercising at levels significantly above the recommendations. Prenatal physical activity should be considered a front-line therapy for reducing the risk of pregnancy complications and enhancing maternal physical and mental health. For pregnant women not currently meeting this guideline, a progressive adjustment toward them is recommended. Previously active women may continue physical activity throughout pregnancy. Women may need to modify physical activity as pregnancy progresses. There may be periods when following the guideline is not possible due to fatigue and/or discomforts of pregnancy; women are encouraged to do what they can and to return to following the recommendations when they are able. This guideline were informed by an extensive systematic review of the literature, expert opinion, end-user consultation and considerations of feasibility, acceptability, costs, and equity.

RECOMMENDATIONS

The specific recommendations in this 2019 Canadian Guideline for Physical Activity Throughout Pregnancy are provided below with corresponding statements indicating the quality of the evidence informing the recommendations and the strength of the recommendations (explanations follow).

CONTRAINDICATIONS

All pregnant women can participate in physical activity throughout pregnancy with the exception of those who have contraindications (listed below). Women with absolute contraindications may continue their usual activities of daily living but should not participate in more strenuous activities. Women with relative contraindications should discuss the advantages and disadvantages of moderate-to-vigorous intensity physical activity with their obstetric care provider prior to participation. Absolute contraindications to exercise are the following: Relative contraindications to exercise are the following: STRENGTH OF THE RECOMMENDATIONS: The GRADE system was utilized to grade the strength of the recommendations. Recommendations are rated as strong or weak based on the: (1) balance between benefits and harms; (2) overall quality of the evidence; (3) importance of outcomes (i.e., values and preferences of pregnant women); (4) use of resources (i.e., cost); (5) impact on health equity; (6) feasibility, and (7) acceptability. Strong recommendation: Most or all pregnant women will be best served by the recommended course of action. Weak recommendation: Not all pregnant women will be best served by the recommended course of action; there is a need to consider other factors such as the individual's circumstances, preferences, values, resources available, or setting. Consultation with an obstetric care provider may assist in decision-making.

QUALITY OF THE EVIDENCE

The quality of the evidence refers to the level of confidence in the evidence and ranges from very low to high. High quality: The Guideline Consensus Panel is very confident that the estimated effect of physical activity on the health outcome is close to the true effect. Moderate quality: The Guideline Consensus Panel is moderately confident in the estimated effect of physical activity on the health outcome; the estimate of the effect is likely to be close to the true effect, but there is a possibility that it is substantially different. Low quality: The Guideline Consensus Panel's confidence in the estimated effect of physical activity on the health outcome is limited; the estimate of the effect may be substantially different from the true effect. Very low quality: The Guideline Consensus Panel has very little confidence in the estimated effect of physical activity on the health outcome; the estimate of the effect is likely to be substantially different from the true effect. ^aThis was a weak recommendation because the quality of evidence was low, and the net benefit between women who were physically active and those who were not was small. ^bThis was a strong recommendation because, despite low quality evidence supporting physical activity during pregnancy for women categorized as overweight or obese, there was evidence from randomized controlled trials demonstrating an improvement in gestational weight gain and blood glucose. ^cModerate-intensity physical activity is intense enough to noticeably increase heart rate; a person can talk but not sing during activities of this intensity. Examples of moderate-intensity physical activity include brisk walking, water aerobics, stationary cycling (moderate effort), resistance training, carrying moderate loads, and household chores (e.g., gardening, washing windows). ^dThis was a weak recommendation because urinary incontinence was was not rated as a "critical" outcome and the evidence was low quality. ^eThis was a weak recommendation because: (1) the quality of evidence was very low; and (2) although harms were investigated there was limited available information to inform the balance of benefits and harms. This recommendation was primarily based on expert opinion.