Impact of prenatal exercise on maternal harms, labour and delivery outcomes: a systematic review and meta-analysis

Effectiveness of Moderate-Intensity Aerobic Water Exercise during Pregnancy on Quality of Life and Postpartum Depression: A Multi-Center, Randomized Controlled Trial

Background: The global prevalence of postpartum depression is about 20%. This disease has serious consequences for women, their infants, and their families. The aim of this randomized clinical trial was to analyze the effectiveness and safety of a moderate-intensity aerobic water exercise program on postpartum depression, sleep problems, and quality of life in women at one month after delivery. Methods: This was a multi-center, parallel, randomized, evaluator blinded, controlled trial in a primary care setting. Pregnant women (14–20 weeks gestational age) who had low risk of complications and were from five primary care centers in the area covered by the obstetrics unit of Son Llatzer Hospital (Mallorca, Spain) were invited to participate. A total of 320 pregnant women were randomly assigned to two groups, an intervention group (moderate aquatic aerobic exercise) and a control group (usual prenatal care). One month after birth, sleep quality (MOS sleep), quality of life (EQ-5D), and presence of anxiety or depression (EPDS) were recorded. Findings: Women in the intervention group were less likely to report anxiety or depression on the EQ5D (11.5% vs. 22.7%; p < 0.05) and had a lower mean EPDS score (6.1 ± 1.9 vs. 6.8 ± 2.4, p < 0.010). The two groups had no significant differences in other outcomes, maternal adverse events, and indicators of the newborn status. Conclusion: Moderate-intensity aquatic exercise during pregnancy decreased postpartum anxiety and depressive symptoms in mothers and was safe for mothers and their newborns.

Physical activity and sleep duration during pregnancy have interactive effects on caesarean delivery: a population-based cohort study in Tianjin, China

Background

There were inconsistent findings in the literature regarding the associations of physical activity and sleep duration during pregnancy with caesarean delivery for different reasons. It was also unknown whether physical activity and sleep duration during pregnancy had interactive effects on the risks of different types of caesarean delivery. The study aimed to investigate the effects of physical activity, sleep duration and their interactions on the risk of caesarean delivery for medical reasons and non-medical reasons.

Methods

From October 2010 to August 2012, a prospective population-based cohort of 13,015 pregnant women was established in six central urban districts of Tianjin, China. Pregnancy outcomes were retrieved from an electronic database and caesarean delivery was divided into caesarean delivery for medical reasons and caesarean delivery for non-medical reasons. Physical activity and sleep status were collected at 24–28 weeks of gestation using self-reported questionnaires. Logistic regression and additive interaction were used to examine physical activity, sleep duration and their interactive effects on risk of caesarean delivery.

Results

In the cohort, 5692 (43.7%) and 2641 (20.3%) of women had caesarean delivery for medical reasons and non-medical reasons, respectively. Low physical activity increased the risk of caesarean delivery for medical reasons (adjusted OR: 1.13, 95%CI 1.04–1.23) but not caesarean delivery for non-medical reasons. Sleep duration < 7 h/day and poor sleep quality were not associated with caesarean delivery. Sleep duration ≥9 h/day increased the risk of caesarean delivery for medical reasons (1.12, 1.02–1.22) and caesarean delivery for non-medical reasons (1.16, 1.05–1.29). Co-presence of low physical activity and sleep duration ≥9 h/day increased risk of caesarean delivery (1.25, 1.12–1.41), and their additive interaction was statistically significant for caesarean delivery for medical reasons but not for caesarean delivery for non-medical reasons.

Conclusions

Low physical activity and excessive sleep duration during pregnancy each increased the risk of caesarean delivery, and they had an interactive effect on the risk of caesarean delivery for medical reasons but not on the risk of caesarean delivery for non-medical reasons. Increasing physical activity and maintaining recommended sleep duration during pregnancy may have benefits for perinatal health.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03788-4.

Asia-Pacific consensus on physical activity and exercise in pregnancy and the postpartum period

Physical activity and exercise in pregnancy are generally beneficial and enhance the physical and mental health of women. These benefits also prevent excessive weight gain and reduce risks of obesity in pregnancy, such as gestational diabetes, hypertensive disorders, higher rates of caesarean delivery, macrosomia and stillbirth. Thus, there is a need to optimise perinatal exercise and physical activity globally. There is currently no consensus recommendation on the role of physical activity and exercise in pregnancy and the postpartum period in the Asia-Pacific region. In this paper, we present seven key consensus recommendations on physical activity and exercise in pregnancy and the postpartum period by 18 key members representing 10 countries in Asia-Pacific regions during an international workshop of the Asia

Diabetes in Pregnancy Conference in Singapore on 11–12 January 2020. Through these consensus recommendations, we hope to improve the metabolic health of pregnant women living in Asia-Pacific regions by educating the public and guiding healthcare professionals on the safety and importance of physical exercise and activity to benefit pregnant women and after childbirth.

Misreporting of Physical Activity and Sedentary Behavior in Parents-to-Be: A Validation Study across Sex

This study validated the International Physical Activity Questionnaire (IPAQ) and the Context-specific Sedentary Behavior Questionnaire (CSBQ) against accelerometry among parents-to-be. Sex-differences in potential misreporting of physical activity (PA) and sedentary behavior (SB) were also investigated. Self-reported total PA (TPA), light-intensity PA (LPA), moderate-intensity PA (MPA), vigorous-intensity PA (VPA), moderate-to-vigorous-intensity PA (MVPA), and SB of 91 parents-to-be (41 men and 50 women) were compared with Actigraph data according to sex. Furthermore, the extent of misreporting was compared between sexes. Strong correlations for TPA and weak-to-moderate correlations for LPA, MPA, VPA, MVPA, and SB were observed. Participants underestimated TPA by 1068 min/week (=17.8 h/week; −50%), LPA by 1593 min/week (=26.6 h/week; −83%), and SB by 428 min/week (=7.1 h/week; −11%) and overestimated MPA by 384 min/week (=6.4 h/week; +176%) and MVPA by 525 min/week (=8.8 h/week; +224%). Males overreported VPA more than females in absolute minutes per week (238 min/week, i.e., 4.0 h/week vs. 62 min/week, i.e., 1.0 h/week), whereas, in relative terms, the opposite (+850% vs. +1033%) was true. The IPAQ and CSBQ can be used with caution to estimate TPA and SB among parents-to-be considering a strong correlation but low agreement for TPA and a weak-to-moderate correlation but acceptable agreement for SB. We disadvise using these self-reports to estimate PA on the distinct intensity levels.

Does exercise during pregnancy impact organs or structures of the maternal-fetal interface?

Exercise during pregnancy has been shown to be associated with improved health outcomes both during and after pregnancy for mother and fetus across the lifespan. Increasing physical activity and reducing sedentary behaviour during pregnancy have been recommended by many researchers and clinicians-alike. It is thought that the placenta plays a central role in mediating any positive or negative pregnancy outcomes. The positive outcomes obtained through prenatal exercise are postulated to result from exercise-induced regulation of maternal physiology and placental development. Considerable research has been performed to understand the placenta's role in pregnancy-related diseases, such as preeclampsia, fetal growth restriction, and gestational diabetes mellitus. However, little research has examined the potential for healthy lifestyle and behavioural changes to improve placental growth, development, and function. While the placenta represents the critical maternal-fetal interface responsible for all gas, nutrient, and waste exchange between the mother and fetus, the impact of exercise during pregnancy on placental biology and function is not well known. This review will focus on prenatal exercise and its promising influence on the structures of the maternal-fetal interface, with particular emphasis on the placenta. Potential molecular mechanistic hypotheses are presented to aid future investigations of prenatal exercise and placental health.

Beneficial intergenerational effects of exercise on brain and cognition: a multilevel meta-analysis of mean and variance

Physical exercise not only helps to improve physical health but can also enhance brain development and cognition. Recent reports on parental (both maternal and paternal) effects raise the possibility that parental exercise may provide benefits to offspring through intergenerational inheritance. However, the general magnitude and consistency of parental exercise effects on offspring is still controversial. Additionally, empirical research has long overlooked an important aspect of exercise: its effects on variability in neurodevelopmental and cognitive traits. Here, we compiled data from 52 studies involving 4786 rodents (412 effect sizes) to quantify the intergenerational transmission of exercise effects on brain and cognition. Using a multilevel meta-analytic approach, we found that, overall, parental exercise showed a tendency for increasing their offspring's brain structure by 12.7% (albeit statistically non-significant) probably via significantly facilitating neurogenesis (16.5%). Such changes in neural anatomy go in hand with a significant 20.8% improvement in neurobehaviour (improved learning and memory, and reduced anxiety). Moreover, we found parental exercise significantly reduces inter-individual differences (i.e. reduced variance in the treatment group) in progeny's neurobehaviour by 10.2% (coefficient of variation ratio, lnCVR), suggesting the existence of an individual by intervention interaction. The positive effects of exercise are modulated by several covariates (i.e. moderators), such as the exercised parent's sex, offspring's sex, and age, mode of exercise, and exercise timing. In particular, parental forced exercise is more efficient than voluntary exercise at significantly improving offspring neurobehaviour (26.0%) and reducing its variability (14.2%). We observed larger effects when parental exercise started before pregnancy. However, exercising only during pregnancy also had positive effects. Mechanistically, exercise significantly upregulated brain-derived neurotrophic factor (BDNF) by 28.9%, vascular endothelial growth factor (VEGF) by 35.8%, and significantly decreased hippocampal DNA methylation by 3.5%, suggesting that brain growth factor cascades and epigenetic modifications can moderate the transmission of parental exercise effects. Collectively, by coupling mean with variance effects, our analyses draw a more integrated picture of the benefits that parental exercise has on offspring: not only does it improve offspring brain development and cognitive performance, but it also reduces inter-individual differences in cognition-related traits. We advocate that meta-analysis of variation together with the mean of a trait provides novel insights for old controversies as well as emerging new questions, opening up a new era for generating variance-based hypotheses.

The Effectiveness of Smoking Cessation, Alcohol Reduction, Diet and Physical Activity Interventions in Improving Maternal and Infant Health Outcomes: A Systematic Review of Meta-Analyses

Diet, physical activity, smoking and alcohol behaviour-change interventions delivered in pregnancy aim to prevent adverse pregnancy outcomes. This review reports a synthesis of evidence from meta-analyses on the effectiveness of interventions at reducing risk of adverse health outcomes. Sixty-five systematic reviews (63 diet and physical activity; 2 smoking) reporting 602 meta-analyses, published since 2011, were identified; no data were identified for alcohol interventions. A wide range of outcomes were reported, including gestational weight gain, hypertensive disorders, gestational diabetes (GDM) and fetal growth. There was consistent evidence from diet and physical activity interventions for a significantly reduced mean gestational weight gain (ranging from -0.21 kg (95% confidence interval -0.34, -0.08) to -5.77 kg (95% CI -9.34, -2.21). There was evidence from larger diet and physical activity meta-analyses for a significant reduction in postnatal weight retention, caesarean delivery, preeclampsia, hypertension, GDM and preterm delivery, and for smoking interventions to significantly increase birth weight. There was no statistically significant evidence of interventions having an effect on low or high birthweight, neonatal intensive care unit admission, Apgar score or mortality outcomes. Priority areas for future research to capitalise on pregnancy as an opportunity to improve the lifelong wellbeing of women and their children are highlighted.

Elite Athletes and Pregnancy Outcomes: A Systematic Review and Meta-analysis

PURPOSE

The purpose of this systematic review was to evaluate fetal and maternal pregnancy outcomes of elite athletes who had participated in competitive sport immediately before conception.

METHODS

Online databases were searched up to March 24, 2020. Studies of any design and language were eligible if they contained information on the relevant population (pregnant women), exposure (engaged in elite sport immediately before pregnancy), and outcomes (birth weight, low birth weight, macrosomia, preterm birth, fetal heart rate and pulse index, cesarean sections, instrumental deliveries, episiotomies, duration of labor, perineal tears, pregnancy-induced low back pain, pelvic girdle pain, urinary incontinence, miscarriages, prenatal weight gain, inadequate/excess prenatal weight gain, maternal depression or anxiety).

RESULTS

Eleven unique studies (n = 2256 women) were included. We identified "low" certainty evidence demonstrating lower rates of low back pain in elite athletes compared with active/sedentary controls (n = 248; odds ratio, 0.38; 95% confidence interval, 0.20-0.73; I2 = 0%) and "very low" certainty evidence indicating an increased odds of excessive prenatal weight gain in elite athletes versus active/sedentary controls (n = 1763; odds ratio, 2.47; 95% confidence interval, 1.26-4.85; I2 = 0%). Low certainty evidence from two studies (n = 7) indicated three episodes of fetal bradycardia after high-intensity exercise that resolved within 10 min of cessation of activity. No studies reported inadequate gestational weight gain or maternal depression or anxiety. There were no differences between elite athletes and controls for all other outcomes.

CONCLUSIONS

There is "low" certainty of evidence that elite athletes have reduced odds of experiencing pregnancy-related low back pain and "very low"certainty of evidence that elite athletes have increased the odds of excessive weight gain compared with active/sedentary controls. More research is needed to provide strong evidence of how elite competitive sport before pregnancy affects maternal and fetal outcomes.PROSPERO Registration: CRD42020167382.

Physical activity and sedentary time during pregnancy and associations with maternal and fetal health outcomes: an epidemiological study

Background

Physical activity is generally considered safe for the pregnant woman as well as for her fetus. In Sweden, pregnant women without contraindications are recommended to engage in physical activity for at least 30 min per day most days of the week. Physical activity during pregnancy has been associated with decreased risks of adverse health outcomes for the pregnant woman and her offspring. However, there are at present no recommendations regarding sedentary behavior during pregnancy. The aim was to examine the level of physical activity and sedentary time in a representative sample of the pregnant population in Sweden, and to explore potential effects on gestational age, gestational weight gain, birth weight of the child, mode of delivery, blood loss during delivery/postpartum, self-rated health during pregnancy and risk of pregnancy-induced hypertension and preeclampsia.

Methods

This was an epidemiological study using data from the prospective, population-based NorthPop study in Northern Sweden and information on pregnancy outcomes from the national Swedish Pregnancy Register (SPR). A questionnaire regarding physical activity and sedentary time during pregnancy was answered by 2203 pregnant women. Possible differences between categories were analyzed using one-way Analysis of variance and Pearson’s Chi-square test. Associations between the level of physical activity/sedentary time and outcome variables were analyzed with univariable and multivariable logistic regression and linear regression.

Results

Only 27.3% of the included participants reported that they reached the recommended level of physical activity. A higher level of physical activity was associated with a reduced risk of emergency caesarean section, lower gestational weight gain, more favorable self-rated health during pregnancy, and a decreased risk of exceeding the Institute of Medicine’s recommendations regarding gestational weight gain. Higher sedentary time was associated with a non-favorable self-rated health during pregnancy.

Conclusions

Our study showed that only a minority of pregnant women achieved the recommended level of physical activity, and that higher physical activity and lower sedentary time were associated with improved health outcomes. Encouraging pregnant women to increase their physical activity and decrease their sedentary time, may be important factors to improve maternal and fetal/child health outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03627-6.

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.

Developing a Physical Activity Intervention Strategy for Pregnant Women in Buffalo City Municipality, South Africa: A Study Protocol

Despite global awareness about the importance and health benefits of physical activity (PA) during pregnancy, several studies have reported a low prevalence of PA participation among pregnant women in both developed and developing countries. This means that most pregnant women do not meet the current PA recommended guideline of 150 min of moderate intensity PA per week. The global call to prioritise PA participation levels in the general population necessitates evaluating the factors affecting PA practice. Seemingly, pregnant women mostly from low-to-middle income countries like South Africa are often predisposed to adverse pregnancy outcomes, possibly because of limited access to, and knowledge of, improved pregnancy and health outcomes as a result of PA participation. Physical activity has been sparsely studied among pregnant South African women, and specifically, there is no known study that assesses the PA levels, patterns, beliefs, sources of information, perceived benefits, barriers, attitudes of pregnant women concerning PA and exercise participation; nor one that explores the perspectives of healthcare providers regarding prenatal PA in the Eastern Cape Province. In addition, no PA intervention strategy exists to promote PA participation in the region. This study, in attempting to fill these gaps in knowledge, adopts two phases. In Phase I, a concurrent mixed-method (quantitative and qualitative) approach assesses the following factors related to PA participation in pregnant women: participation levels, beliefs, attitudes, perceived benefits, barriers to uptake and sources of information. It further ascertains if healthcare professionals are sufficiently informed about PA and if they are advising pregnant women about the need for PA participation during pregnancy. Data will be collected through a structured questionnaire, interviews and focus group discussions. Information on socio-demographic and maternal characteristics will be obtained, and the Pregnancy Physical Activity Questionnaire (PPAQ) will assess PA during pregnancy. A sample size of 384 pregnant women is the required minimum sample for an infinite population at a confidence level of 95%, a precision level of ± 5% and at a prevalence of PA or exercise during pregnancy of 50% (p < 0.05); however, a sample size larger than the minimum number necessary will be recruited to account for possible attrition and to protect against possible data loss. Data will be analysed using a multiple logistic regression to determine the factors that predict sedentary or moderate PA levels and chi-squared analysis to determine the associations between the PA levels of the participants and socio-demographic and clinical variables. The study will assess the data collected on the above-mentioned variables and draw conclusions based on patterns and themes that emerge during analysis. Phase II of the study focuses on strategy development and validation to facilitate the promotion of PA during pregnancy. The developed strategy will be validated through the application of the Delphi technique and the administration of a checklist to selected key stakeholders through organised workshops. Understanding the level and correlates of PA participation among this special population is fundamental to designing intervention strategies to enhance their understanding of, and participation in, PA and exercise. Furthermore, this study's findings will inform facility-based healthcare providers about the need to integrate health education on PA and pregnancy into antenatal and postnatal care visits in the setting.

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 exercise on pregnancy and postpartum fatigue: A systematic review and meta-analysis

OBJECTIVE

Fatigue is a common adverse experience in pregnant and postpartum women and is associated with poor outcomes and can seriously affect maternal and infant health and quality of life. However, data from existing studies are inconsistent, and no studies have examined the effects of exercise on pregnancy and postpartum fatigue. The aim of this review is to evaluate the effects of exercise on pregnancy and postpartum fatigue.

STUDY DESIGN

PubMed, EMBASE, Web of Science and the Cochrane Library database were used to retrieve literature. Eligible studies were clinical trials that reported the effects of exercise on pregnancy and postpartum fatigue in women. The methodological quality of the included studies was assessed using the Cochrane Collaboration Risk of Bias Assessment Tool. A fixed-effect model was used to analyse the pooled results. Subgroup analyses were used to explore sources of heterogeneity. Sensitivity analysis was used to validate the robustness of the pooled results.

RESULTS

Seven studies were included. The results of meta-analysis of five studies showed that exercise during pregnancy and the postpartum period may have beneficial effects on women's fatigue ([SMD = 0.29, 95 % CI (0.10, 0.47), P = 0.003]). Subgroup analyses reported that compared with the control, long exercise programmes, postpartum exercise and supervised exercise significantly improved fatigue levels.

CONCLUSIONS

Postpartum exercise in a supervised programme lasting more than eight weeks may be beneficial for reducing postpartum fatigue. More available data from large-scale and high-quality trials are needed to demonstrate the effects of exercise on pregnant and postpartum fatigue.

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.

Exploring Beliefs About Exercise Among Pregnant Women in Rural Communities

INTRODUCTION

Women who are pregnant in rural communities are disproportionally impacted by obesity and sedentary behavior, and this could be related to having negative beliefs about exercise during pregnancy, leading to inactivity. The purpose of this study was to identify self-reported beliefs about exercise among pregnant women in a rural community.

METHODS

Pregnant participants (N = 70) between 8 and 16 weeks' gestation were recruited from an obstetric clinic serving a rural population. An open-ended questionnaire addressing beliefs about exercise and based on the constructs of the theory of planned behavior was administered. Descriptive survey results were analyzed by calculating means and frequencies. Open-ended responses were assessed by inductive content analysis.

RESULTS

Commonly reported advantages of exercise during pregnancy included improved perinatal health outcomes and weight management. Commonly reported disadvantages included an increase in fatigue and concerns for maternal and fetal safety. Common facilitators of exercise included access to resources, free time or a decrease in demands from work, and support systems including family and friends. Common barriers to exercise included a lack of time, physical changes including feelings of nausea and fatigue, and lack of access to resources.

DISCUSSION

This study was the first to report beliefs about exercise during pregnancy in a rural setting. Responses in the current study suggest potential gaps in knowledge of evidence-based information regarding physical activity during pregnancy. Beliefs as well as reported barriers and facilitators of physical activity during pregnancy were similar those reported in other populations. In addition, access to resources (or lack of) appears to be an important facilitator (or barrier) among women in rural settings; thus, developing strategies designed to overcome this barrier, specifically in rural areas, is critically important. Future intervention strategies need to be tailored specifically to the needs of women living in rural areas.

What Accounts for Physical Activity during Pregnancy? A Study on the Sociodemographic Predictors of Self-Reported and Objectively Assessed Physical Activity during the 1st and 2nd Trimesters of Pregnancy

Physical activity (PA) during pregnancy has positive health implications for both mother and child. However, current literature indicates that not all pregnant women meet the international recommendations for PA (at least 150 min/week of moderate-to-vigorous PA). The main objective of this study was to assess PA levels among pregnant women in the city of Donostia-San Sebastian and identify their main sociodemographic predictors. We recruited 441 women in the 12th week of pregnancy from the local public obstetric health services. Women wore an accelerometer for one week during two separate time points (1st and 2nd trimesters of pregnancy) and completed a questionnaire assessing several sociodemographic variables as well as self-reported PA. With this information, we estimated women’s overall PA levels during both time points. The fulfillment of PA recommendations raised up to 77% and 85% during the first and second trimesters, respectively. We found that a higher number of children and a greater preference for exercise positively predicted light-to-moderate PA, being the most consistent predictors. The availability of a greater number of cars negatively predicted moderate-to-vigorous PA.

Associations of Pregnancy Physical Activity with Maternal Cardiometabolic Health, Neonatal Delivery Outcomes and Body Composition in a Biethnic Cohort of 7305 Mother-Child Pairs: The Born in Bradford Study

OBJECTIVE

Physical activity is advocated for a range of benefits to the uncomplicated pregnancy. We investigated associations of mid-pregnancy physical activity with maternal and neonatal health in white British and Pakistani-origin women from a deprived urban setting.

METHODS

The study was performed in 6921 pregnant women (53% Pakistani-origin) who contributed data for 7305 singleton births. At 26-28 weeks gestation, women were grouped into four activity levels (inactive/somewhat active/moderately active/active) based on their self-reported physical activity. Linear regression with robust standard errors was used to calculate adjusted mean differences in health markers between the four groups of physical activity (reference group: inactive).

RESULTS

Three-quarters (74%) of Pakistani-origin women and 39% of white British women were inactive. Trend-tests revealed that more active white British women tended to be less adipose, had lower fasting and postload glucose levels, lower triglyceride concentrations, and their babies were less adipose (smaller triceps and subscapular skinfolds) than less active white British women. Somewhat active Pakistani-origin women exhibited lower triglyceride concentrations and systolic blood pressure, higher high-density lipoprotein cholesterol levels, and their babies were less adipose (smaller mid-upper arm and abdominal circumferences; lower cord-blood leptin concentration) compared to inactive Pakistani-origin women. No associations were observed for gestational age or birth weight.

CONCLUSIONS

Physical activity performed mid-pregnancy was beneficially associated with maternal cardiometabolic health and neonatal adiposity, without influencing gestational age or birth weight. Associations were dose-dependent in white British women, and even a small amount of mid-pregnancy physical activity appeared to benefit some health markers in Pakistani-origin women.

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.

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.

Is Physical Activity Good or Bad for the Female Pelvic Floor? A Narrative Review

More women participate in sports than ever before and the proportion of women athletes at the Olympic Games is nearly 50%. The pelvic floor in women may be the only area of the body where the positive effect of physical activity has been questioned. The aim of this narrative review is to present two widely held opposing hypotheses on the effect of general exercise on the pelvic floor and to discuss the evidence for each. Hypothesis 1: by strengthening the pelvic floor muscles (PFM) and decreasing the levator hiatus, exercise decreases the risk of urinary incontinence, anal incontinence and pelvic organ prolapse, but negatively affects the ease and safety of childbirth. Hypothesis 2: by overloading and stretching the PFM, exercise not only increases the risk of these disorders, but also makes labor and childbirth easier, as the PFM do not obstruct the exit of the fetus. Key findings of this review endorse aspects of both hypotheses. Exercising women generally have similar or stronger PFM strength and larger levator ani muscles than non-exercising women, but this does not seem to have a greater risk of obstructed labor or childbirth. Additionally, women that specifically train their PFM while pregnant are not more likely to have outcomes associated with obstructed labor. Mild-to-moderate physical activity, such as walking, decreases the risk of urinary incontinence but female athletes are about three times more likely to have urinary incontinence compared to controls. There is some evidence that strenuous exercise may cause and worsen pelvic organ prolapse, but data are inconsistent. Both intra-abdominal pressure associated with exercise and PFM strength vary between activities and between women; thus the threshold for optimal or negative effects on the pelvic floor almost certainly differs from person to person. Our review highlights many knowledge gaps that need to be understood to understand the full effects of strenuous and non-strenuous activities on pelvic floor health.

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.

Associations between Prenatal Physical Activity and Neonatal and Obstetric Outcomes-A Secondary Analysis of the Cluster-Randomized GeliS Trial

Prenatal physical activity (PA) was discussed to decrease the incidence of obstetric and neonatal complications. In this secondary cohort analysis of the cluster-randomized GeliS (“healthy living in pregnancy”) trial, associations between prenatal PA and such outcomes were investigated. PA behavior was assessed twice, before or during the 12th week (baseline, T0) and after the 29th week of gestation (T1), using the self-reported Pregnancy Physical Activity Questionnaire. Obstetric and neonatal data were collected in the routine care setting. Data were available for 87.2% (n = 1994/2286) of participants. Significant differences between the offspring of women who adhered to PA recommendations at T1 and offspring of inactive women were found in birth weight (p = 0.030) but not in other anthropometric parameters. Sedentary behavior was inversely associated with birth weight at T1 (p = 0.026) and, at both time points, with an increase in the odds of low birth weight (T0: p = 0.004, T1: p = 0.005). Light-intensity PA at T0 marginally increased the odds of caesarean section (p = 0.032), but neither moderate-intensity nor vigorous-intensity activity modified the risk for caesarean delivery at any time point. The present analyses demonstrated associations between prenatal PA and some neonatal and obstetric outcomes.

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.

2019 Canadian guideline for physical activity throughout pregnancy

The objective is to provide guidance for pregnant women and obstetric care and exercise professionals on prenatal physical activity. The outcomes evaluated were maternal, fetal or neonatal morbidity, or fetal mortality during and following pregnancy. 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, Education Resources Information Center, SPORTDiscus, ClinicalTrials.gov and the Trip Database from inception up to 6 January 2017. Primary studies of any design were eligible, except case studies. Results were limited to English-language, Spanish-language 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 methodology. The Guidelines Consensus Panel solicited feedback from end users (obstetric care providers, exercise professionals, researchers, policy organisations, and pregnant and postpartum women). The development of these guidelines followed the Appraisal of Guidelines for Research and Evaluation II instrument. 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.

Impact of prenatal exercise on neonatal and childhood outcomes: a systematic review and meta-analysis

Objective

We aimed to identify the relationship between maternal prenatal exercise and birth complications, and neonatal and childhood morphometric, metabolic and developmental outcomes.

Design

Systematic review with random-effects meta-analysis and meta-regression.

Data sources

Online databases were searched up to 6 January 2017.

Study eligibility criteria

Studies of all designs were eligible (except case studies and reviews) if published in English, Spanish or French, and contained information on the relevant population (pregnant women without contraindication to exercise), intervention (subjective/objective measures of frequency, intensity, duration, volume or type of exercise, alone (‘exercise-only’) or in combination with other intervention components (eg, dietary; ‘exercise+cointervention’)), comparator (no exercise or different frequency, intensity, duration, volume, type or trimester of exercise) and outcomes (preterm birth, gestational age at delivery, birth weight, low birth weight (<2500 g), high birth weight (>4000 g), small for gestational age, large for gestational age, intrauterine growth restriction, neonatal hypoglycaemia, metabolic acidosis (cord blood pH, base excess), hyperbilirubinaemia, Apgar scores, neonatal intensive care unit admittance, shoulder dystocia, brachial plexus injury, neonatal body composition (per cent body fat, body weight, body mass index (BMI), ponderal index), childhood obesity (per cent body fat, body weight, BMI) and developmental milestones (including cognitive, psychosocial, motor skills)).

Results

A total of 135 studies (n=166 094) were included. There was ‘high’ quality evidence from exercise-only randomised controlled trials (RCTs) showing a 39% reduction in the odds of having a baby >4000 g (macrosomia: 15 RCTs, n=3670; OR 0.61, 95% CI 0.41 to 0.92) in women who exercised compared with women who did not exercise, without affecting the odds of growth-restricted, preterm or low birth weight babies. Prenatal exercise was not associated with the other neonatal or infant outcomes that were examined.

Conclusions

Prenatal exercise is safe and beneficial for the fetus. Maternal exercise was associated with reduced odds of macrosomia (abnormally large babies) and was not associated with neonatal complications or adverse childhood outcomes.