Impact of postpartum physical activity on cardiometabolic health, breastfeeding, injury and infant growth and development: a systematic review and meta-analysis.

OBJECTIVE: To examine the relationship between postpartum physical activity and maternal postnatal cardiometabolic health, breastfeeding, injury, and infant growth and development. DESIGN: Systematic review with random-effects meta-analysis and meta-regression. DATA SOURCES: Eight online databases were searched up until 12 January 2024. ELIGIBILITY CRITERIA: Studies of all designs in all languages were eligible (except case studies and reviews) if they contained information on the population (postpartum people), intervention (frequency, intensity, duration, volume, or type of exercise, alone ('exercise-only') or in combination with other intervention components (eg, dietary; 'exercise+co-intervention'), comparator (no or low volumes of physical activity), and outcomes: hypertension, diabetes, cardiometabolic risk factors (systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol, high density lipoproteins, low density lipoproteins, and triglycerides, glycated hemoglobin (HbA1C), glucose and insulin concentration), breastfeeding (breast milk quality and volume), infant growth (length and weight) and development, or postpartum injury. RESULTS: 46 unique studies (n=8766 participants) from 20 countries were included. Moderate certainty of evidence showed exercise+co-interventions reduced the odds of developing diabetes by 28% (7 randomised controlled trials (RCTs), n=2496; OR 0.72 95% CI 0.54, 0.98, I2 12%), reduced SBP (10 RCTs, n=2753; mean difference (MD) -2.15 95% CI -3.89 to -0.40, I2 73%) and DBP (9 RCTs, n=2575; MD -1.38 95% CI -2.60 to -0.15, I2 66%) compared with controls. Infant growth and development, breast milk quality and quantity, and risk of injury were not different between exercise and control groups. CONCLUSIONS: Physical activity improves cardiometabolic health without adversely impacting breast milk supply or quality, infant growth or maternal injury.

The 'new normal' includes online prenatal exercise: exploring pregnant women's experiences during the pandemic and the role of virtual group fitness on maternal mental health.

BACKGROUND: Prenatal anxiety and depressive symptoms have significantly increased since the onset of the coronavirus (COVID-19) pandemic In addition, home confinement regulations have caused a drastic increase in time spent sedentary. Online group fitness classes may be an effective strategy that can increase maternal physical activity levels and improve mental health outcomes by providing an opportunity for social connectedness. The present study explores the experiences of pregnant women who participated in an online group exercise program during the pandemic and identifies relationships with maternal mental health and well-being. In addition, we present person-informed recommendations on how to improve the delivery of future online prenatal exercise programs. METHODS: Semi-structured interviews were conducted with pregnant women (8-39 weeks of pregnancy) who participated in an online group exercise program, from March to October 2020 in Spain. A phenomenological approach was taken, and open-ended questions were asked to understand women's experiences throughout the pandemic and the role the online exercise classes may have had on their physical activity levels, mental health, and other health behaviours such as diet. A thematic analysis was performed to evaluate data. In addition, women completed the State-Trait Anxiety Inventory and these data supplemented qualitative findings. RESULTS: Twenty-four women were interviewed, and the anxiety scores were on average 32.23 ± 9.31, ranging from low to moderate levels. Thematic analysis revealed that women felt safe exercising from home, an increased availability of time to schedule a structured exercise class, and consequently an improvement in their adherence to the program and other behaviours (i.e., healthier diet). Women emphasized feeling connected to other pregnant women when they exercised online together, and overall, this had a positive effect on their mental well-being. Women suggested that future online exercise programs should include flexible options, detailed instructions and facilitation by a qualified exercise professional. CONCLUSION: Pregnant women are receptive to online group exercise classes and expressed that they are an accessible option to accommodating physical activity during the pandemic. In addition, the online group environment provides an important sense of connectivity among pregnant women exercising together and this may mitigate the detrimental effect of COVID-19 on maternal mental health.

How Do Health Schemas Inform Healthy Behaviours During Pregnancy? Qualitative Findings from the Be Healthy in Pregnancy (BHIP) Study.

OBJECTIVE: Excess gestational weight gain (GWG) is associated with adverse long and short-term outcomes for both woman and child, yet evidence demonstrates pregnant women are frequently not engaging in healthy behaviours linked to appropriate weight gain. The purpose of the current study was to explore women's values and beliefs related to weight, nutrition and physical activity during pregnancy and to describe how these beliefs influence their behaviours. METHODS: As part of a larger randomized controlled trial, we conducted 20 focus groups with 66 pregnant women between 16 and 24-weeks gestation using a semi-structured interview guide. Focus groups were recorded and transcribed verbatim and analyzed using a grounded theory approach. RESULTS: Three personal health schemas emerged from the findings which illustrated women's diverging beliefs about their health behaviours in pregnancy. 'Interconnected health' described beliefs regarding the impact their health had on that of their growing baby and awareness of risks associated with inappropriate weight gain. 'Gestational weight gain as an indicator of health' illustrated perceptions regarding how GWG impacted health and the utility of guidelines. Finally, 'Control in pregnancy' described the sense of agency over one's body and health. CONCLUSIONS FOR PRACTICE: Our results showed that health-related behaviours in pregnancy are driven by personal health schemas which are often discordant with clinical evidence. Interventions and health care provider advice aimed at behaviour modification would benefit from first understanding and addressing these schemas. Tackling the conflict between beliefs and behaviour may improve health outcomes associated with appropriate weight gain in pregnancy.

Physical activity and prenatal depression: going beyond statistical significance by assessing the impact of reliable and clinical significant change.

BACKGROUND: Previous literature supports exercise as a preventative agent for prenatal depression; however, treatment effects for women at risk for prenatal depression remain unexplored. The purpose of the study was to examine whether exercise can lower depressive symptoms among women who began pregnancy at risk for depression using both a statistical significance and reliable and clinically significant change criteria. METHODS: This study is a secondary analysis of two randomized controlled trials that followed the same exercise protocol. Pregnant women were allocated to an exercise intervention group (IG) or control group (CG). All participants completed the Center for Epidemiological Depression (CES-D) scale at gestational week 9-16 and 36-38. Women with a baseline score ⩾16 were included. A clinically reliable cut-off was calculated as a 7-point change in scores from pre- to post-intervention. RESULTS: Thirty-six women in the IG and 25 women in the CG scored ⩾16 on the CES-D at baseline. At week 36-38 the IG had a statistically significant lower CES-D score (14.4 ± 8.6) than the CG (19.4 ± 11.1; p < 0.05). Twenty-two women in the IG (61%) had a clinically reliable decrease in their post-intervention score compared to eight women in the CG (32%; p < 0.05). Among the women who met the reliable change criteria, 18 (81%) in the IG and 7 (88%) in the CG had a score <16 post-intervention, with no difference between groups (p > 0.05). CONCLUSIONS: A structured exercise program might be a useful treatment option for women at risk for prenatal depression.

Be Healthy in Pregnancy: Exploring factors that impact pregnant women's nutrition and exercise behaviours.

Excess gestational weight gain is associated with short- and long-term pregnancy complications. Although a healthy diet and physical activity during pregnancy are recommended and shown to reduce the risk of complications and improve outcomes, adherence to these recommendations is low. The aims of this study were to explore women's view of nutrition and physical activity during pregnancy and to describe barriers and facilitators experienced in implementing physical activity and nutrition recommendations. In a substudy of the Be Healthy in Pregnancy randomized trial, 20 semistructured focus groups were conducted with 66 women randomized to the control group when they were between 16 and 24 weeks gestation. Focus groups were recorded, transcribed verbatim, coded and thematically analysed. The results indicate that women felt motivated to be healthy for their baby, but competing priorities may take precedence. Participants described limited knowledge and access to information on safe physical activity in pregnancy and lacked the skills needed to operationalize both physical activity and dietary recommendations. Women's behaviours regarding diet and physical activity in pregnancy were highly influenced by their own and their peers' beliefs and values regarding how weight gain impacted their health during pregnancy. Pregnancy symptoms beyond women's control such as fatigue and nausea made physical activity and healthy eating more challenging. Counselling from care providers about nutrition and physical activity was perceived as minimal and ineffective. Future interventions should address improving counselling strategies and address individual's beliefs around nutrition and activity in pregnancy.

Physical activity throughout pregnancy is key to preventing chronic disease.

According to The Developmental Origins of Health and Disease theory, the intrauterine environment of the developing fetus may impact later life physiology, including susceptibility to chronic disease conditions. Maternal exposures during pregnancy can affect the intrauterine environment and result in fetal programming for chronic diseases through changes in the structure or function of specific organs. Negative maternal exposures, such as poor nutrition intake, have been shown to increase the risk for later life chronic diseases. On the contrary, healthful behaviors, such as physical activity, may have a positive and protective effect against chronic disease risk. This narrative review summarizes literature to discuss the potential preventative role prenatal physical activity may have on prevalent chronic diseases: obesity, type 2 diabetes, and cardiovascular disease. We describe the natural physiological response to pregnancy that may increase the risk for complications and consequently later life disease for both mother and baby. We then present evidence highlighting the role prenatal exercise may have in preventing pregnancy complications and downstream chronic disease development, as well as proposing potential mechanisms that may explain the protective maternal and fetal physiological response to exercise. As the prevalence of these non-communicable diseases increase globally, intervening during pregnancy with an effective exercise intervention may be the key to preventing chronic disease risk in more than one generation.

Summer Season and Recommended Vitamin D Intake Support Adequate Vitamin D Status throughout Pregnancy in Healthy Canadian Women and Their Newborns.

BACKGROUND: Vitamin D deficiency in pregnancy is reported as a prevalent public health problem. OBJECTIVES: We aimed to evaluate, in pregnant Canadian women, 1) vitamin D intake, 2) maternal and cord serum 25-hydroxycholecalciferol [25(OH)D] and maternal 1,25-dihydroxycholecalciferol [1,25(OH)2D], and 3) factors associated with maternal serum 25(OH)D. METHODS: Women (n = 187; mean prepregnancy BMI 24.4 kg/m2, mean age 31 y) recruited to the Be Healthy in Pregnancy study provided fasting blood samples and nutrient intake at 12-17 (early) and 36-38 (late) weeks of gestation, and cord blood. Vitamin D intakes (Nutritionist Pro™) and serum 25(OH)D and 1,25(OH)2D concentrations (LC-tandem MS) were measured. RESULTS: Vitamin D intake was comparable in early and late pregnancy [median (IQR) = 586 (459, 859) compared with 689 (544, 974) IU/d; P = 0.83], with 71% consumed as supplements. Serum 25(OH)D was significantly higher in late pregnancy (mean ± SD: 103.1 ± 29.3 nmol/L) than in early pregnancy (82.5 ± 22.5 nmol/L; P < 0.001) and no vitamin D deficiency (<30 nmol/L) occurred. Serum 1,25(OH)2D concentrations were significantly higher in late pregnancy (101.1 ± 26.9 pmol/L) than in early pregnancy (82.2 ± 19.2 pmol/L, P < 0.001, n = 84). Cord serum 25(OH)D concentrations averaged 55% of maternal concentrations. In adjusted multivariate analyses, maternal vitamin D status in early pregnancy was positively associated with summer season (est.ß: 13.07; 95% CI: 5.46, 20.69; P < 0.001) and supplement intake (est.ß: 0.01; 95% CI: 0.00, 0.01; P < 0.001); and in late pregnancy with summer season (est.ß: 24.4; 95% CI: 15.6, 33.2; P < 0.001), nonmilk dairy intake (est.ß: 0.17; 95% CI: 0.02, 0.32; P = 0.029), and supplement intake (est.ß: 0.01; 95% CI: 0.00, 0.01; P = 0.04). CONCLUSIONS: Summer season and recommended vitamin D intakes supported adequate vitamin D status throughout pregnancy and in cord blood at >50 nmol/L in healthy Canadian pregnant women. This trial was registered at clinicaltrials.gov as NCT01693510.

Are pre-pregnancy weight fluctuations and adherence to prenatal nutrition and exercise recommendations related to excessive gestational weight gain?

Women who have an overweight or obese pre-pregnancy body mass index (BMI) may be recommended to lose weight before pregnancy, however the association of preconception weight fluctuations and prenatal adherence to nutrition and exercise recommendations with gestational weight gain (GWG) have not been assessed. One hundred women with a pre-pregnancy BMI ≥ 25.0 kg/m2 who participated in the Nutrition and Exercise Lifestyle Intervention Program (NELIP) were included and stratified as gained weight excessively (n = 47) or not (n = 53) using the 2009 Institute of Medicine GWG guidelines. Participants completed a Weight Health History Questionnaire providing information about weight loss prior to the index pregnancy. Adherence was scored based on meeting six nutrition and exercise goals for the NELIP (/6). More women who gained excessively reported that they had actively tried to lose weight a year before the current pregnancy (61%) than women who did not gain excessively (39%; p = 0.02). Of the women attempting preconception weight loss, those who gained excessively lost more weight (6.7 ± 10.2 kg) than women who did not (2.1 ± 3.8 kg; p = 0.003). Adherence to the NELIP was lower among women who gained excessively (3.3 ± 0.8; 55%) than those who did not (4.4 ± 0.9;73%; p < 0.001). Program adherence (p < 0.001) was related to excessive GWG.

Sequential Introduction of Exercise First Followed by Nutrition Improves Program Adherence During Pregnancy: a Randomized Controlled Trial.

BACKGROUND: Adhering to nutrition and exercise recommendations simultaneously during pregnancy may be challenging. The purpose was to examine adherence to the sequential introduction of nutrition and exercise behaviors during pregnancy in comparison with a simultaneous approach. METHOD: A randomized controlled trial including nutrition and exercise was executed. Using a stratified body mass index (BMI) randomization, participants (n = 88) were allocated to one of three groups at 12-18 weeks gestation. Group A received nutrition and exercise simultaneously. Group B received nutrition first and Group C received exercise first, and the second behavior was added at 25 weeks gestation for both groups. The program included weekly weighing, supervised walking sessions, and/or nutrition counseling. Adherence (primary outcome) was measured by scoring women on meeting the intervention goals (3 nutrition and 3 exercise goals) and converted to a percentage. Secondary health outcomes were gestational weight gain (GWG) and excessive GWG on the program, birthweight, macrosomia (birthweight > 4000 g), and low birthweight (birthweight < 2500 g). RESULTS: Group C (n = 23) had the highest adherence to the program (80.2 ± 14.7%) compared with Groups A (n = 17; 60.9 ± 17.9%) and B (n = 20; 66.8 ± 16.7%; p < 0.05, ηp2 = 0.26). There was a significant effect for gestational weight gain (p < 0.05; ηp2 = 0.10) as Group C gained less weight (7.7 ± 2.2 kg) over Group B (9.8 ± 2.8 kg; p = 0.04), however, not Group A (9.1 ± 3.5, p = 0.35). Non-significant small effects favored Group C for the prevention of EGWG (Cramer's V = 0.13). CONCLUSION: Introducing exercise first followed by nutrition at 25 weeks gestation can improve adherence to multiple behavior change programs and thus have a positive effect on health outcomes. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02804061.

Diet in Early Pregnancy: Focus on Folate, Vitamin B12, Vitamin D, and Choline.

Purpose: Prenatal multivitamins are recommended in pregnancy. This study assessed food and supplement intakes of folate, vitamin B12 (B12), vitamin D, and choline in pregnant women living in Southern Ontario in comparison with current recommendations. Methods: Women recruited to the Be Healthy in Pregnancy RCT (NCT01693510) completed 3-day diet/supplement records at 12-17 weeks gestation. Intakes of folate, B12, vitamin D, and choline were quantified and compared with recommendations for pregnant women. Results: Folate intake (median (min, max)) was 1963 µg/day dietary folate equivalents (153, 10 846); 90% of women met the Estimated Average Requirement (EAR) but 77% exceeded the Tolerable Upper Intake Level (UL) (n = 232). B12 intake was 12.1 µg/day (0.3, 2336); 96% of women met the EAR with 7% exceeding the EAR 100-fold (n = 232). Vitamin D intake was 564 IU/day (0.0, 11 062); 83% met the EAR, whereas 1.7% exceeded the UL (n = 232). Choline intake was 338 mg/day (120, 1016); only 18% met the Adequate Intake and none exceeded the UL (n = 158). Conclusion: To meet the nutrient requirements of pregnancy many women rely on prenatal vitamins. Reformulating prenatal multivitamin supplements to provide doses of vitamins within recommendations to complement a balanced healthy diet would ensure appropriate micronutrient intakes for pregnant women.

Experiences regarding nutrition and exercise among women during early postpartum: a qualitative grounded theory study.

BACKGROUND: Excess gestational weight gain has long- and short-term implications for women and children, and postpartum weight retention is associated with an increased risk of long-term obesity. Despite the existence of dietary and exercise guidelines, many women struggle to return to pre-pregnancy weight. Experiences of women in tackling postpartum weight loss are poorly understood. We undertook this study to explore experiences related to nutrition, exercise and weight in the postpartum in women in Ontario, Canada. METHODS: This was a nested qualitative study within The Be Healthy in Pregnancy Study, a randomized controlled trial. Women randomized to the control group were invited to participate. Semi-structured focus groups were conducted at 4-6 months postpartum. Focus groups were audio recorded, transcribed verbatim, coded and analyzed thematically using a constructivist grounded theory approach. RESULTS: Women experienced a complex relationship with their body image, due to unrealistic expectations related to their postpartum body. Participants identified barriers and enablers to healthy habits during pregnancy and postpartum. Gestational weight gain guidelines were regarded as unhelpful and unrealistic. A lack of guidance and information about weight management, healthy eating, and exercise in the postpartum period was highlighted. CONCLUSION: Strategies for weight management that target the unique characteristics of the postpartum period have been neglected in research and in patient counselling. Postpartum women may begin preparing for their next pregnancy and support during this period could improve their health for subsequent pregnancies. TRIAL REGISTRATION: NCT01689961 registered September 21, 2012.

Glycated hemoglobin measurements at three, 12 and 24 months postpartum after gestational diabetes.

PURPOSE: To determine the associations between glycated hemoglobin (A1C) values at three, 12 and 24 months postpartum taken during the Families Defeating Diabetes trial. METHODS: The Families Defeating Diabetes trial was a randomized 12 month lifestyle intervention delivered in the first year postpartum. Women were reviewed at three, 6 12 and 24 months for body habitus, diet and lifestyle choices. Glycated hemoglobin levels were measured at three, 12 and 24 months. RESULTS: There were 170 randomization participants: 89 interventional (INT); and 81 control (CON). Of these 170 participants, 50 INT and 47 CON completed 12-month follow-up and 26 INT and 24 CON completed 24-month follow-up. Study outcomes did not differ between the cohorts. Combined intraclass correlation coefficients for reliability of repeated results showed substantial reliability: 0.74 (95% CI 0.63, 0.83) between three and 12 month A1C; and 0.72 (95% CI 0.51, 0.85) for three and 24 month A1C. Pearson correlations for three month vs 12 month A1C were r=0.745 (p.

Physical exercise programme during pregnancy decreases perinatal depression risk: a randomised controlled trial.

INTRODUCTION: The incidence of depression is high during the perinatal period. This mood disorder can have a significant impact on the mother, the child and the family. OBJECTIVE: To examine the effect of an exercise programme during pregnancy on the risk of perinatal depression. METHODS: Healthy women who were <16 weeks pregnant were randomly assigned to two different groups. Women in the intervention group participated in a 60 min exercise programme throughout pregnancy, 3 days per week, which was conducted from October 2014 to December 2016. The Center for Epidemiological Studies-Depression Scale was used to measure the risk of depression at the beginning of the study (12-16 weeks), at gestational week 38 and at 6 weeks postpartum. RESULTS: One hundred and twenty-four pregnant women were allocated to either the intervention (IG=70) or the control (CG=54) group. No differences were found in the percentage of depressed women at baseline (20% vs 18.5%) (χ2=0.043; p=0.836). A smaller percentage of depressed women were identified in the IG compared with the CG at 38 gestational weeks (18.6% vs 35.6%) (χ2=4.190; p=0.041) and at 6 weeks postpartum (14.5% vs 29.8%) (χ2=3.985; p=0.046) using the per-protocol analysis. No significant differences were found using the intention-to-treat analyses, except in the multiple imputation analysis at week 38 (18.6% vs 34.4%) (χ2=4.085; p=0.049). CONCLUSION: An exercise programme performed during pregnancy may reduce the prevalence of depression in late pregnancy and postpartum. TRIAL REGISTRATION NUMBER: NCT02420288; Results.

Effects of prenatal exercise on fetal heart rate, umbilical and uterine blood flow: a systematic review and meta-analysis.

OBJECTIVE: To perform a systematic review and meta-analysis examining the influence of acute and chronic prenatal exercise on fetal heart rate (FHR) and umbilical and uterine blood flow metrics. 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 included (except case studies) if published in English, Spanish or French, and contained information on the population (pregnant women without contraindication to exercise), intervention (subjective or objective measures of frequency, intensity, duration, volume or type of exercise, alone ["exercise-only"] or in combination with other intervention components [eg, dietary; "exercise + co-intervention"]), comparator (no exercise or different frequency, intensity, duration, volume and type of exercise) and outcomes (FHR, beats per minute (bpm); uterine and umbilical blood flow metrics (systolic:diastolic (S/D) ratio; Pulsatility Index (PI); Resistance Index (RI); blood flow, mL/min; and blood velocity, cm/s)). RESULTS: 'Very low' to 'moderate' quality evidence from 91 unique studies (n=4641 women) were included. Overall, FHR increased during (mean difference (MD)=6.35bpm; 95% CI 2.30 to 10.41, I2=95%, p=0.002) and following acute exercise (MD=4.05; 95% CI 2.98 to 5.12, I2=83%, p<0.00001). The incidence of fetal bradycardia was low at rest and unchanged with acute exercise. There were no significant changes in umbilical or uterine S/D, PI, RI, blood flow or blood velocity during or following acute exercise sessions. Chronic exercise decreased resting FHR and the umbilical artery S/D, PI and RI at rest. CONCLUSION: Acute and chronic prenatal exercise do not adversely impact FHR or uteroplacental blood flow metrics.

Is supine exercise associated with adverse maternal and fetal outcomes? A systematic review.

OBJECTIVE: Theoretical concerns regarding the supine position at rest due to the gravid uterus obstructing aorta and vena caval flow may impinge uterine blood flow (UBF) to the fetus and maternal venous return. DESIGN: Systematic review. DATA SOURCES: Online databases up to 11 December 2017. STUDY CRITERIA: Eligible population (pregnant without contraindication to exercise), intervention (frequency, intensity, duration, volume or type of supine exercise), comparator (no exercise or exercise in left lateral rest position, upright posture or other supine exercise), outcomes (potentially adverse effects on maternal blood pressure, cardiac output, heart rate, oxygen saturation, fetal movements, UBF, fetal heart rate (FHR) patterns; adverse events such as bradycardia, low birth weight, intrauterine growth restriction, perinatal mortality and other adverse events as documented by study authors), and study design (except case studies and reviews) published in English, Spanish, French or Portuguese. RESULTS: Seven studies (n=1759) were included. 'Very low' to 'low' quality evidence from three randomised controlled trials indicated no association between supervised exercise interventions that included supine exercise and low birth weight compared with no exercise. There was 'very low' to 'low' quality evidence from four observational studies that showed no adverse events in the mother; however, there were abnormal FHR patterns (as defined by study authors) in 20 of 65 (31%) fetuses during an acute bout of supine exercise. UBF decreased (13%) when women moved from left lateral rest to acute dynamic supine exercise. CONCLUSION: There was insufficient evidence to ascertain whether maternal exercise in the supine position is safe or should be avoided during pregnancy.

Exercise for the prevention and treatment of low back, pelvic girdle and lumbopelvic pain during pregnancy: a systematic review and meta-analysis.

OBJECTIVE: The purpose of this review was to investigate the relationship between prenatal exercise, and low back (LBP), pelvic girdle (PGP) and lumbopelvic (LBPP) pain. 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 they were published in English, Spanish or French, and contained information on the population (pregnant women without contraindication to exercise), intervention (subjective or objective measures of frequency, intensity, duration, volume or type of exercise, alone ["exercise-only"] or in combination with other intervention components [eg, dietary; "exercise + co-intervention"]), comparator (no exercise or different frequency, intensity, duration, volume and type of exercise) and outcome (prevalence and symptom severity of LBP, PGP and LBPP). RESULTS: The analyses included data from 32 studies (n=52 297 pregnant women). 'Very low' to 'moderate' quality evidence from 13 randomised controlled trials (RCTs) showed prenatal exercise did not reduce the odds of suffering from LBP, PGP and LBPP either in pregnancy or the postpartum period. However, 'very low' to 'moderate' quality evidence from 15 RCTs identified lower pain severity during pregnancy and the early postpartum period in women who exercised during pregnancy (standardised mean difference -1.03, 95% CI -1.58, -0.48) compared with those who did not exercise. These findings were supported by 'very low' quality evidence from other study designs. CONCLUSION: Compared with not exercising, prenatal exercise decreased the severity of LBP, PGP or LBPP during and following pregnancy but did not decrease the odds of any of these conditions at any time point.

Prenatal exercise is not associated with fetal mortality: a systematic review and meta-analysis.

OBJECTIVE: To perform a systematic review of the relationship between prenatal exercise and fetal or newborn death. 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 included (except case studies) if they were published in English, Spanish or French and contained information on the population (pregnant women without contraindication to exercise), intervention (subjective or objective measures of frequency, intensity, duration, volume or type of exercise, alone ["exercise-only"] or in combination with other intervention components [eg, dietary; "exercise + co-intervention"]), comparator (no exercise or different frequency, intensity, duration, volume and type of exercise) and outcome (miscarriage or perinatal mortality). RESULTS: Forty-six studies (n=2 66 778) were included. There was 'very low' quality evidence suggesting no increased odds of miscarriage (23 studies, n=7125 women; OR 0.88, 95% CI 0.63 to 1.21, I2=0%) or perinatal mortality (13 studies, n=6837 women, OR 0.86, 95% CI 0.49 to 1.52, I2=0%) in pregnant women who exercised compared with those who did not. Stratification by subgroups did not affect odds of miscarriage or perinatal mortality. The meta-regressions identified no associations between volume, intensity or frequency of exercise and fetal or newborn death. As the majority of included studies examined the impact of moderate intensity exercise to a maximum duration of 60 min, we cannot comment on the effect of longer periods of exercise. SUMMARY/CONCLUSIONS: Although the evidence in this field is of 'very low' quality, it suggests that prenatal exercise is not associated with increased odds of miscarriage or perinatal mortality. In plain terms, this suggests that generally speaking exercise is 'safe' with respect to miscarriage and perinatal mortality.

Effects of prenatal exercise on incidence of congenital anomalies and hyperthermia: a systematic review and meta-analysis.

OBJECTIVE: To investigate the relationships between exercise and incidence of congenital anomalies and hyperthermia. DESIGN: Systematic review with random-effects meta-analysis . DATA SOURCES: Online databases were searched from inception up to 6 January 2017. STUDY ELIGIBILITY CRITERIA: Studies of all designs were eligible (except case studies and reviews) if they were published in English, Spanish or French, and contained information on population (pregnant women without contraindication to exercise), intervention (subjective or objective measures of frequency, intensity, duration, volume or type of exercise, alone ["exercise-only"] or in combination with other intervention components [e.g., dietary; "exercise + co-intervention"]), comparator (no exercise or different frequency, intensity, duration, volume or type of exercise) and outcome (maternal temperature and fetal anomalies). RESULTS: This systematic review and meta-analysis included 'very low' quality evidence from 14 studies (n=78 735) reporting on prenatal exercise and the odds of congenital anomalies, and 'very low' to 'low' quality evidence from 15 studies (n=447) reporting on maternal temperature response to prenatal exercise. Prenatal exercise did not increase the odds of congenital anomalies (OR 1.23, 95% CI 0.77 to 1.95, I2=0%). A small but significant increase in maternal temperature was observed from pre-exercise to both during and immediately after exercise (during: 0.26°C, 95% CI 0.12 to 0.40, I2=70%; following: 0.24°C, 95% CI 0.17 to 0.31, I2=47%). SUMMARY/CONCLUSIONS: These data suggest that moderate-to-vigorous prenatal exercise does not induce hyperthermia or increase the odds of congenital anomalies. However, exercise responses were investigated in most studies after 12 weeks' gestation when the risk of de novo congenital anomalies is negligible.

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

OBJECTIVE: To perform a systematic review of the relationships between prenatal exercise and maternal harms including labour/delivery outcomes. DESIGN: Systematic review with random effects meta-analysis and meta-regression. DATASOURCES: Online databases were searched up to 6 January 2017. STUDY ELIGIBILITY CRITERIA: Studies of all designs were included (except case studies) if they were published in English, Spanish or French and contained information on the population (pregnant women without contraindication to exercise), intervention (subjective or objective measures of frequency, intensity, duration, volume or type of exercise), comparator (no exercise or different frequency, intensity, duration, volume and type of exercise, alone ["exercise-only"] or in combination with other intervention components [e.g., dietary; "exercise + co-intervention"]) and outcome (preterm/prelabour rupture of membranes, caesarean section, instrumental delivery, induction of labour, length of labour, vaginal tears, fatigue, injury, musculoskeletal trauma, maternal harms (author defined) and diastasis recti). RESULTS: 113 studies (n=52 858 women) were included. 'Moderate' quality evidence from exercise-only randomised controlled trials (RCTs) indicated a 24% reduction in the odds of instrumental delivery in women who exercised compared with women who did not (20 RCTs, n=3819; OR 0.76, 95% CI 0.63 to 0.92, I 2= 0 %). The remaining outcomes were not associated with exercise. Results from meta-regression did not identify a dose-response relationship between frequency, intensity, duration or volume of exercise and labour and delivery outcomes. SUMMARY/CONCLUSIONS: Prenatal exercise reduced the odds of instrumental delivery in the general obstetrical population. There was no relationship between prenatal exercise and preterm/prelabour rupture of membranes, caesarean section, induction of labour, length of labour, vaginal tears, fatigue, injury, musculoskeletal trauma, maternal harms and diastasis recti.

No 129-L'exercice physique pendant la grossesse et le postpartum.

OBJECTIF: Énoncer une directive canadienne visant à informer les fournisseurs de soins obstétricaux des répercussions, pour la mère, le fœtus et le nouveau-né, des exercices de conditionnement aerobique et musculaire pendant la grossesse. RéSULTATS ATTENDUS: Effets sur la morbidité maternelle, fœtale et néonatale et mesures de la forme physique maternelle. PREUVES: Une recherche sur MEDLINE des articles, publiés en anglais de 1966 à 2002, appartenant aux catégories suivantes : études sur le conditionnement aérobique et musculaire chez des femmes ne faisant pas jusque-là d'exercice et chez des femmes actives avant leur grossesse, ainsi que des études sur les répercussions du conditionnement aérobique et musculaire sur les issues précoces et tardives de la grossesse ou sur les issues néonatales; rapports de synthèse et méta-analyses portant sur l'exercice pendant la grossesse. VALEURS: Les résultats recueillis ont été revus par la Société des obstétriciens et gynécologues du Canada (Comité de la pratique clinique - obstétrique), avec la participation de la Société canadienne de physiologie de l'exercice, et ils ont été classés suivant les critères d'évaluation des preuves établis par le Groupe de travail canadien sur l'examen de santé périodique. RECOMMANDATIONS: VALIDATION: Cette directive a été approuvée par le Comité de pratique clinique - obstétrique de la SOGC, par le Comité exécutif et par le Conseil de la SOGC, ainsi que par le Conseil d'administration de la Société canadienne de physiologie de l'exercice. PARRAINé PAR: la Société des obstétriciens et gynécologues du Canada et par la Société canadienne de physiologie de l'exercice.