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

Exceeding the guidelines: A descriptive study of exercise, pregnancy, maternal and neonatal health outcomes in elite and recreational athletes

BACKGROUND

Exercise during pregnancy is associated with numerous health benefits. However, guidelines for elite and recreational athletes, who often exceed general recommendations regarding intensity, duration, and frequency are lacking, and potential risks remain unclear. The aim of the study was to describe exercise levels, pregnancy, and maternal and neonatal health outcomes in elite and recreational athletes.

METHOD

This study was part of the Strong Mama research project, which was carried out in Oslo, Norway, between October 2022 and February 2024. Sixty athletes (10 elite and 50 recreational) participated in the study. They completed an online survey during late pregnancy and participated in a structured telephone interview six weeks postpartum. The survey and interview collected data on exercise habits, pregnancy experiences, and maternal and neonatal health outcomes.

RESULTS

The athletes maintained high exercise levels during pregnancy, with elite athletes exercising an average of 11.6 h per week (SD 3.2) and recreational athletes exercising 7.0 h per week (SD 2.4). Most athletes resumed exercising within six weeks postpartum. Almost all pregnancies were planned, including six which involved fertility treatment. Most women (76.7%) had spontaneous onset of labor and vaginal deliveries to term (between 36 and 42 weeks). The mean birthweight was 3487 (SD 519.4, range 2600-4775) grams. Two of the elite athletes were diagnosed with gestational diabetes mellitus and two with hypertension during pregnancy. None of the 50 recreational athletes reported any pregnancy complications.

CONCLUSION

High levels of exercise during pregnancy did not seem to negatively impact maternal or neonatal health in this descriptive sample of Norwegian elite and recreational athletes. However, more research is needed to confirm these findings.

Midwives' Knowledge, Attitudes, and Professional Practices Regarding Prenatal Physical Activity

Background/Objectives: Prenatal physical activity (PA) offers numerous health benefits for both the mother and her child, yet few pregnant women are sufficiently active enough to obtain these benefits. Midwives play an important role in promoting prenatal PA. However, little is known about the content of the information they share with their clients regarding prenatal PA, how they communicate it, and the personal factors that might influence their counseling. In the context of prenatal PA guidance, the aim of this study was to describe the knowledge, attitudes, professional practices, and communication methods used by midwives. Methods: A cross-sectional descriptive study was conducted between February and June 2024 among midwives working in the Province of Quebec. An electronic questionnaire including both closed (quantitative data) and open-ended (qualitative data) questions was developed. Results: Fifty midwives were included in the analysis. Only 28 (56%) reported being aware of the latest Canadian guidelines for PA throughout pregnancy. The recommendations provided varied in terms of content and accuracy but were often conservative (i.e., not focused on increasing PA). Forty-five (90%) mentioned providing information on PA to their pregnant client, and eighty-four (84%) said they used bidirectional communication to share this information. The vast majority (84%) did not consider their counseling to be optimal, primarily due to a lack of training and knowledge. Conclusions: Our finding allowed us to gain a better understanding of current midwifery knowledge, attitudes, and professional practices regarding prenatal PA and to initiate a reflection on how to improve their knowledge, skills, and confidence in guiding their client toward prenatal PA.

Physical activity during pregnancy: key beliefs to support intervention

Background

Physical activity (PA) provides maternal and fetal health benefits, but only 27.5% of Canadian pregnant women meet PA recommendations. Theory-based interventions like the theory of planned behavior (TPB) are useful in explaining what drives behavior. The first objective of this study was to validate the TPB model to predict prenatal moderate-to-vigorous physical activity (MVPA), including testing of the novel interaction between intention and perceived behavioral control (PBC). The second objective was to identify which specific beliefs predict intention toward prenatal MVPA to support intervention.

Method

We used a prospective correlational design. Healthy pregnant women completed two electronic questionnaires: at baseline, to assess TPB constructs, and one month later, to assess MVPA practice. Structural equation modeling was conducted with Latent Moderated Structural Equations. The interaction was interpreted with the pick-a-point method and the Johnson-Neyman graphical method.

Results

The sample consists of 193 women (M age = 31.2±3.6). Results indicate that prenatal MVPA at one month was marginally predicted by intention (β = 0.149; p < 0.10) and PBC (β = 0.322; p < 0.05, MVPA R 2 = 20%), but when their interaction was added to the model, MVPA R 2 increased to 44%. Specifically, the relationship between intention and MVPA is stronger when PBC is high (0.5 standard deviation over the mean). In the full model including the interaction, attitude (β = 0.59; p < 0.001), subjective norm (β = 0.20; p < 0.01) and PBC (β = 0.26; p < 0.05) all made a significant contribution to predicting MVPA intention (R 2  = 88%). Finally, the following beliefs displayed significant indirect paths toward the intention of being physically active: behavioral beliefs: unlikely to be more tired and likely feel better mentally; normative beliefs: approval from friends and from mother/father; and control beliefs: being tired and missing social support.

Conclusion

Interventions aiming to promote regular MVPA during pregnancy should prioritized the six significant beliefs identified to significantly predict intention toward prenatal MVPA.

Maternal exercise during pregnancy is associated with reduced risk of asthma in the child: A prospective birth cohort study

BACKGROUND

The means of primary prevention of asthma are limited. Maternal physical activity during pregnancy promotes fetal lung development and the newborn's lung function; thus, it could lower asthma risk and aid in asthma prevention. The objective of this study is to determine whether maternal physical activity during pregnancy is associated with asthma development in the child.

METHODS

The study population included 963 mother-infant pairs from the prospective Kuopio Birth Cohort study. Data on maternal physical activity during pregnancy, confounding factors, and children's asthma at 5 to 7 years of age were obtained from the Kuopio University Hospital birth registry and questionnaires.

FINDINGS

Maternal physical activity during pregnancy, when practiced three or more times per week, was associated with a reduced risk of asthma in the child, with an adjusted odds ratio of 0.54 (95% confidence interval 0.33-0.89; p = 0.02). The association was stable across a comprehensive set of adjustments, including length of gestation, mode of delivery, and maternal health indicators (e.g., asthma, smoking, pre-pregnancy body mass index and weight gain during pregnancy, infections, medication, healthy diet, stress), as well as various family environment variables.

CONCLUSIONS

Maternal physical activity during pregnancy may be associated with marked protection of asthma in childhood and should be studied further as an applicable measure for asthma prevention.

FUNDING

The study has been financially supported by grants from the Academy of Finland (no. 349427), the Emil Aaltonen Foundation, the Finnish Cultural Foundation, the Yrjö Jahnsson Foundation, the Juho Vainio Foundation (no. 202200461), the Kuopio Area Respiratory Foundation, and the Ida Montini Foundation.

Sex-specific associations between feto-placental growth and maternal physical activity volume and sitting time: Findings from the Queensland Family Cohort study

INTRODUCTION

Antenatal physical activity (PA) is associated with beneficial changes in placental growth and function; however, the effect of excessive sitting time is less clear. The aim of this study was to investigate whether feto-placental growth changes with maternal activity, and whether these associations differ in a sex-specific manner.

METHODS

This study included women enrolled in the Queensland Family Cohort study who self-reported PA and sitting time at 24 or 36 weeks of gestation. Placental growth factors and feto-placental growth parameters at delivery were analysed by PA volume and sitting time, as well as by fetal sex.

RESULTS

Women who reported excessive sitting time during mid-pregnancy and had a female fetus showed higher placental PlGF (p = 0.031) and FLT1 (p = 0.032) mRNA expression with no difference in placental size at delivery. For the male, excessive sitting time during mid-pregnancy was associated with a lower placental weight (p = 0.001) and placental surface area (p = 0.012) and a higher birthweight to placental weight (BWPW) ratio (p = 0.042), with no change in placental growth factors. Moderate volume PA during mid-pregnancy was associated with lower VEGFA mRNA expression in the male placenta (p = 0.005) and a higher abdominal circumference in the female neonate (p = 0.042), with no overall difference in placental weight or birthweight for either sex.

CONCLUSIONS

The results of this study suggest that mid-pregnancy may be an important timepoint for programming of feto-placental growth in relation to maternal activity. Our findings highlight the independent benefits of reducing sitting time during pregnancy, particularly for women carrying male fetuses.

Physical behaviours during pregnancy may alter the association of maternal insulin sensitivity with neonatal adiposity: a prospective pre-birth cohort of mother-child pairs

BACKGROUND

Lower maternal insulin sensitivity during pregnancy is associated with greater fetal adiposity. Physical activity can improve insulin sensitivity, but it is not known if physical behaviours influence the known association of maternal insulin sensitivity with offspring adiposity. This study aimed to investigate the moderating impact of physical behaviours on this association.

METHODS

Pregnant women (n = 812) from the Gen3G cohort were recruited during the first trimester of pregnancy and followed until delivery. At the first (V1) and second trimester (V2) hospital visits, Gen3G staff measured anthropometry, and participants reported sleep duration as well as leisure physical activity and sedentary behaviour via lifestyle questionnaires. We used plasma glucose and insulin values from the 75 g oral glucose tolerance test at V2 to calculate insulin sensitivity using the Matsuda index. We recorded birthweight from electronic medical records. Among a subset of neonates (n = 265), trained research staff measured skinfold thickness using a calibrated skinfold caliper following standardized protocols to estimate neonatal adiposity. Linear regression analyses assessed the association of insulin sensitivity with birthweight z-score and sum of neonatal skinfold thickness, adjusting for maternal age, race/ethnicity, gravidity, smoking, with and without adjustment for maternal body mass index at V1. We evaluated moderation by physical activity, sedentary behaviour, or nighttime sleep duration using interaction terms and stratified analyses for the association of maternal insulin sensitivity with offspring birthweight and with offspring adiposity.

RESULTS

Lower Matsuda index was associated with higher birthweight z-score (ß±SE= -0.180 ± 0.056, p = 0.001) and with higher sum of skinfold thickness (neonatal adiposity) (ß±SE=-0.877 ± 0.383, p = 0.02) in fully adjusted models. The association between Matsuda index and sum of skinfold thickness was weaker in women with higher levels of physical activity at V2 ([high ≥ 1.26 kcal/kg/day] ß±SE=-0.15 ± 0.65) compared to women with lower levels [low < 1.26 kcal/kg/day] ß±SE=-1.36 ± 0.51, P-interaction = 0.01). We also observed potential interactions of sleep and sedentary behaviour at V2 with Matsuda index for the association with birthweight z-score. We did not observe effect modification by levels of physical behaviours assessed at V1.

CONCLUSION

The association between lower insulin sensitivity and higher neonatal adiposity was attenuated in women with higher physical activity levels in the second trimester, independent of maternal body mass index.

Perspectives of Midwives and Nurse Practitioners in Kentucky on Exercise Counseling During Pregnancy: A Qualitative Study

Introduction

Healthcare professionals are in an optimal position to deliver exercise information to pregnant women, yet previous research suggests this seldom happens. Midwives and nurse practitioners, who may have more time with pregnant women, are particularly well suited for this role.

Objectives

This qualitative study examined the exercise advice and counseling provided by midwives and nurse practitioners in Kentucky, focusing on the barriers they face.

Methods

Twenty-one midwives and nurse practitioners were recruited until the sample size reached saturation. A survey with open-ended questions was distributed to potential participants in regional hospitals, universities, and professional associations. The framework method was employed to identify common themes in the responses from participants.

Results

Five main themes emerged: nature of advice, discussing exercise benefits, safety concerns, barriers to counseling, and suggestions for improvement. Findings revealed that midwives and nurse practitioners recommend moderate exercise, aiming for 150 min weekly, monitoring heart rate for intensity, continuing prepregnancy exercise routines, starting low-intensity exercise during pregnancy such as walking, slowing down as pregnancy advances, and avoiding heavy lifting and vigorous activities. Many midwives and nurse practitioners in our sample took a reactive approach to exercise counseling, providing exercise advice if pregnant women asked questions or if they were at high risk for hypokinetic diseases. It was also observed that midwives and nurse practitioners discussed the maternal benefits of exercise more than the fetal benefits. Only a few nurse practitioners and midwives were content with their counseling, while the majority did not feel their counseling was effective.

Conclusions

Many midwives and nurse practitioners in Kentucky provided comprehensive and accurate physical activity guidelines to pregnant women. However, there is room for them to improve: proactive counseling should include discussions on fetal benefits and using the "talk test" for exercise intensity. Advising patients to slow down as pregnancy progresses should be reconsidered, and evidence-based guidance on specific exercises should be prioritized.

Effect of homemade peanut oil consumption during pregnancy on low birth weight and preterm birth outcomes: a cohort study in Southwestern China

BACKGROUND

Homemade peanut oil is widely consumed in rural areas of Southwestern China, which is easily contaminated by aflatoxins (AFs) and associated with adverse birth outcomes.

OBJECTIVE

To identify the effect of exposure to homemade peanut oil consumption on low birth weight (LBW), preterm birth (PB) and other associated factors.

METHODS

A prospective cohort study was conducted among pregnant women in Guangxi province, Southwestern China. Information of all eligible women on homemade peanut oil consumption and potential factors associated with LBW and PB was collected, and all were followed up until delivery. The effect of homemade peanut oil exposure was analyzed using multiple logistic regression models using the directed acyclic graph (DAG) approach.

RESULTS

Of 1611 pregnant women, 1316 (81.7%) had consumed homemade peanut oil, and the rates of LBW and PB were 9.7% and 10.0%, respectively. Increased risks of LBW and PB in women with homemade peanut oil consumption were found with aORs of 1.9 (95% CI 1.1-3.2) and 1.8 (95% CI 1.1-3.0), respectively. Women with a history of PB or LBW were 3-5 times more likely to have higher rates of LBW or PB compared with those without this type of history. The odds of PB were approximately double in those taking medicine during pregnancy. Advanced maternal age, lack of physical exercise during pregnancy, passive smoking, or pregnancy complications were also more likely to have a higher risk of LBW.

CONCLUSIONS

Homemade peanut oil consumption was a potential risk factor for both LBW and PB, of which health authorities who are responsible for food safety of the country should pay more attention to providing recommendation for oil consumption during pregnancy.

Effects of exercise on vascular remodelling and fetal growth in uncomplicated and abortion-prone mouse pregnancies

Studies in humans and rodents show exercise in pregnancy can modulate maternal blood pressure, vascular volume, and placental efficiency, but whether exercise affects early uteroplacental vascular adaptations is unknown. To investigate this, CBA/J female mice mated with BALB/c males to generate healthy uncomplicated pregnancies (BALB/c-mated) or mated with DBA/2J males to generate abortion-prone pregnancies (DBA/2J-mated), were subjected to treadmill exercise (5 days/week, 10 m/min, 30 min/day for 6 weeks before and throughout pregnancy), or remained sedentary. In uncomplicated pregnancies, exercise caused symmetric fetal growth restriction in fetuses evidenced by reductions in fetal weight, crown-to-rump length, abdominal girth and biparietal diameter. Placental insufficiency was indicated by reduced fetal: placental weight ratio and increased glycogen cell content in the junctional zone of placentas of exercised BALB/c-mated mice on gestational day (GD)18.5. In abortion-prone pregnancy, exercise increased placental efficiency, but the number of late-pregnancy resorptions were elevated. Effects of paternal genotype independent of exercise were evidenced by a greater number of resorptions, poorer spiral artery remodelling, and larger placentas in the DBA/2J-mated compared to BALB/c-mated mice. Effects of exercise independent of paternal genotype included increased implantation sites at both mid and late pregnancy, accompanied by decreased junctional zone areas of placentas. Our findings show that exercise before and during pregnancy in mice can have different effects on fetal outcomes, depending on the paternal and/or fetal genotype. This suggests that the underlying mechanisms are responsive to fetal cues.

Maternal adiposity and perinatal and offspring outcomes: an umbrella review

Maternal adiposity deleteriously affects obstetrical health and has been associated with long-term adverse consequences in offspring. Here we conducted an umbrella review encompassing 194 observational meta-analyses, 10 Mendelian randomization studies and 748 interventional meta-analyses to appraise the published evidence on the associations between maternal adiposity and perinatal and offspring outcomes. Evidence grading suggested that 17 (8.8%) observational meta-analyses were supported by convincing evidence for 12 outcomes: maternal adiposity was associated with an increased risk of caesarean delivery following labour induction, infant mortality, Apgar score <7 at 1 min, antenatal depression, offspring overweight and obesity, early timing of puberty onset in daughters, attention deficit hyperactivity disorder, cerebral palsy, congenital heart disease and spina bifida (OR/RR ranging from 1.14 to 2.31), as well as increased offspring body fat percent and fat mass (SMD 0.31 and 0.35, respectively). Among these outcomes, interventional meta-analyses supported that maternal weight loss interventions significantly reduced the risk of antenatal depression but not low Apgar scores; these interventions also could not reduce offspring fat mass or body fat percent. Evidence from Mendelian randomization studies supported a causal relationship between maternal adiposity and gestational diabetes mellitus, preeclampsia, birth size and offspring adiposity. Our findings highlight that while observational meta-analyses reveal associations between maternal adiposity and various adverse perinatal and offspring outcomes, convincing, unbiased evidence or support from Mendelian randomization studies is limited. Maternal pre-conceptional and prenatal weight loss interventions can reduce some, but not all, of these adverse effects.

Running for two (or three!): the journey of an ultramarathoner across two pregnancies

There is a lack of evidence regarding the safety of long-duration and vigorous-intensity physical activity during pregnancy, such as that required during an ultramarathon. This case study is the first to examine the training, performance, health, and delivery outcomes for an ultramarathoner across two successive pregnancies (one twin and one singleton) that were delivered when the athlete was 41 and 43 yr, respectively. During her twin pregnancy, she ran an average of 91.72 ± 23.17 km across 9.06 ± 2.38 h/wk. Both twins were normal for gestational age and delivered at 37 wk. Twin 2 experienced mild hypoxic-ischemic encephalopathy but made a full recovery following treatment. Twin pregnancy increases the risk of this complication, and there is no evidence to suggest that it is associated with vigorous-intensity endurance activity. During her singleton pregnancy, the participant's distance and pace increased, running on average 157.80 ± 14.69 km across 14.08 ± 1.60 h/wk. She also competed in five races including three ultramarathons and ranked well, with no adverse events during or following each of the races. She delivered prematurely (36 wk and 6 days), but her baby was normal for gestational age.NEW & NOTEWORTHY This study provides the first description of a pregnant female ultramarathoner's training patterns, performance outcomes, and health and birthing outcomes across two pregnancies.

Are there sensitive periods for physical activity to influence the development of executive function in children?

Executive functions emerge throughout childhood and shape multiple cognitive and behavioral outcomes across the lifespan. Given the importance of these functions, there is considerable interest in understanding the role of environmental enrichment to support their development. The past 20 years have seen the emergence of a body of evidence around the beneficial effects of engaging in physical activity for executive functioning in children. Despite this, there are still unanswered questions, particularly about the confounding effects of the timing and dose of exercise-based interventions. During development, sensitive periods with heightened neural plasticity and sensitivity to environmental influences can offer an optimal time to introduce enrichment interventions. As such, sensitive periods for executive function could indicate an ideal time to introduce physical activity or be a potential confounder to study results if not considered. This narrative review discusses the potential presence of sensitive periods in preadolescent development where physical activity has greater benefits for executive function. Initially, we briefly review the largely parallel fields investigating the presence of sensitive periods for executive function and the effects of physical activity on executive function outcomes. We then bring together these 2 concepts to discuss the theoretical basis for developmentally sensitive periods during which children may be particularly amenable to physical activity-based interventions and offer potential ways forward to investigate this phenomenon. We hope this review will attract researchers to collaborate in the area and extend our current understanding of the development of executive functions as well as interventions like physical activity.

Association between maternal exercise during pregnancy and attention-deficit/hyperactivity disorder among preschool children in Southwest China

OBJECTIVE

Maternal moderate-intensity exercise during pregnancy has important health benefits for the offspring, however, less is known about its association with offspring attention-deficit/hyperactivity disorder (ADHD). This study aimed to explore the association between maternal exercise during pregnancy and ADHD among preschool children in Southwest China.

METHODS

A web-based cross-sectional study was performed in 2021, and the revised Conners Parental Symptom Questionnaire and maternal exercise during pregnancy were obtained through a self-reported structured questionnaire. A binary logistic regression model was used to assess the association between maternal exercise during pregnancy and the likelihood of childhood ADHD after adjustment for covariates.

RESULTS

A total of 4,184 preschool children aged 3-6 years were included in our final analysis. Children whose mothers exercised for <20 min per day were more likely to be at risk of ADHD (6.3%), compared to those whose mothers exercised for more than 40 min (3.1%) or 20-40 min (2.8%) per day. Daily exercise of <20 min during pregnancy was associated with higher odds of childhood ADHD (adjusted OR = 2.11; 95% CI: 1.41, 3.16) after multivariable adjustment. The association of maternal exercise during pregnancy with childhood ADHD was similar in subgroups stratified by child's sex, and by maternal smoking, sleep duration and gestational anemia during pregnancy.

CONCLUSION

Our findings highlight the importance of maternal moderate-intensity exercise during pregnancy for the prevention of childhood ADHD. Prospective studies are needed to confirm our findings in the future.

Influence of prenatal aquatic activities on fetal outcomes and maternal physical and mental outcomes: a systematic review and meta-analysis

BACKGROUND

Aquatic activities are becoming increasingly popular as a form of exercise during pregnancy. However, the effects of these activities on the physical and mental health outcomes of pregnant women during and after pregnancy as well as fetal outcomes remain unclear. This meta-analysis evaluated the current evidence regarding the effects of aquatic activities during pregnancy on neonatal and maternal outcomes.

METHODS

Three databases (PubMed, Cochrane Central electronic database, Embase) were searched from inception to July 17, 2024 for randomized controlled trials (RCTs) comparing the effects of aquatic activities versus standard prenatal care or no exercise on neonatal and maternal outcomes. Pooled outcome measures were determined using random-effects models.

RESULTS

Ten RCTs including 1949 patients met the criteria for inclusion in this meta-analysis. The results showed that prenatal aquatic activities could significantly improve maternal weight control (mean difference [MD]= -0.91, 95% confidence interval [CI]= -1.64 to -0.18, P = 0.01, I2 = 0.00%), improve maternal quality of life (standard mean difference [SMD] = 0.16, 95%CI = 0.03 to 0.28, P = 0.01, I2 = 0.00%), and extend fetal birth length (MD = 0.48, 95%CI = 0.10 to 0.87, P = 0.01, I2 = 0.00%) compared with standard prenatal care or no exercise, while no significant differences were observed in fetal birth weight, Apgar score at 1 min, Apgar score at 5 min, pH of umbilical cord blood, gestational age, rate of preterm delivery, incidence of postnatal depression and mode of delivery.

CONCLUSIONS

Prenatal aquatic activities can significantly improve maternal weight control and quality of life during pregnancy, and may promote longer birth length. However, additional studies are needed to confirm these findings.

The association of physical activity during pregnancy with birthweight extremes: A scoping review

OBJECTIVES

Birthweight (BW) indicates newborn health and is a risk factor for development of chronic diseases later in life. The aim was to investigate whether or not prenatal physical activity (PA) influences BW extremes and how PA influences BW extremes in those diagnosed with pregnancy-related diseases.

DESIGN

We performed a scoping review.

METHODS

Searches were completed on five databases and studies identified were uploaded to Covidence.

RESULTS

Across the five databases 3114 studies were identified and after screening, 69 of these studies were used for the final review. Of the 61 studies that considered low BW (LBW)/small for gestational age (SGA) infants, the majority of results (69 %) indicated that PA during pregnancy had no significant impact on LBW or SGA infants. In addition, 11 % of studies reported a significant decrease in the prevalence of LBW infants, however two studies (3 %) reported a significant increase in LBW or SGA infants, likely relating to individuals with high body mass index and poor adherence to PA. Of the 41 studies that did report LGA/macrosomia, 34 % reported that PA significantly reduced the prevalence of higher BW infants. One study reported the association between meeting exercise recommendations and reducing the odds of LGA infants in those with pregnancy-related diseases.

CONCLUSIONS

We provide evidence on the association of prenatal PA with BW extremes. It is suggested that prenatal PA does not increase the risk of delivering LBW/SGA infants and may reduce the prevalence of large BW infants. Further research is needed to confirm these relationships and explain their underlying mechanisms.

"I have not been doing it because of my fear of something happening." Exploring perspectives on healthy dietary behaviors and physical activity in Mexican pregnant women and health care professionals: A qualitative study

OBJECTIVES

Mexico exhibits one of the highest prevalence rates of overweight and obesity globally, accompanied by a surge in non-communicable diseases, which in turn leads to elevated mortality rates. Existing efforts to address rising obesity rates have shown limited effectiveness. Maternal weight, diet, and physical activity (PA) during pregnancy affect the mother's and offspring's health. Despite the importance of establishing and engaging in healthy behaviors during pregnancy, little is known about which factors impact these behaviors among pregnant women in Mexico. This study explored perspectives on factors impacting healthy dietary behaviors and PA in pregnancy from pregnant women and health care professionals in Mexico.

METHODS

We conducted semistructured interviews with 11 pregnant women and 12 health care professionals working in prenatal care. Data were analyzed using qualitative content analysis in a stepwise inductive approach.

RESULTS

Classifying factors at the 1) individual level, 2) relational level, and 3) health care system level, three overall themes emerged. At the individual level, challenges with lack of time and competing priorities as well as knowledge of healthy dietary behaviors and PA were identified. At the relational level, influencing factors encompassed financial, social, and emotional support along with descriptive norms. At the health care system level, guidelines for PA during pregnancy and the quality of care were noted.

CONCLUSIONS

This study identified factors impacting healthy dietary behaviors and PA in pregnancy in Mexico. Important considerations for future interventions include addressing sociocultural norms around healthy dietary behaviors and PA in pregnancy and involving pregnant women's families, closest social networks, and health care professionals working at the prenatal care unit.

An umbrella review of systematic reviews on interventions of physical activity before pregnancy, during pregnancy, and postpartum to control and/or reduce weight gain

BACKGROUND

The increasing prevalence of overweight and obesity worldwide represents a (chronic) complex public health problem. This is also seen among women of childbearing age despite increased efforts to promote physical activity (PA) interventions. Excessive gestational weight gain (GWG) is associated with negative health outcomes for both mothers and offspring.

OBJECTIVES

To summarize current systematic reviews (SRs) on PA interventions during pregnancy and postpartum to prevent excessive GWG and identify the most effective approaches.

SEARCH STRATEGY

A literature search was conducted on major electronic databases (MEDLINE/Pubmed, Cochrane, Web of Science, Epistemonikos) from inception to March 2023.

SELECTION CRITERIA

This study included SRs and meta-analyses of studies involving women aged 18 years or older from diverse ethnic backgrounds, who were either in the preconception period, pregnant, or within 1 year postpartum and who had no contraindications for exercise. Women with chronic diseases, such as pre-existing diabetes (type 1 or type 2) were excluded.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted data from selected studies assessing the impact of PA in preconception, pregnancy, and postpartum. Methodologic quality was assessed with the AMSTAR-2 tool. A narrative summary of results addresses relationships between PA and weight before, during, and after pregnancy, informing future research priorities for preventing excessive weight gain. This study is registered on PROSPERO (CRD420233946666).

MAIN RESULTS

Out of 892 identified articles, 25 studies were included after removing duplicates, unrelated titles, and screening titles and abstracts for eligibility. The results demonstrate that PA can help prevent excessive GWG and postpartum weight retention. Structured and supervised moderate-intensity exercise, at least twice a week, and each session lasting a minimum of 35 min seems to provide the greatest benefits.

CONCLUSIONS

Women who comply with the PA program and recommendations are more likely to achieve adequate GWG and return to their pre-pregnancy body mass index after delivery. Further research is warranted to explore how preconception PA influences pregnancy and postpartum outcomes given the absence of identified preconception-focused interventions.

Trimester-specific association between fetal growth and physical activity in pregnant women: total physical activity vs moderate-to-vigorous exercise

OBJECTIVE

To investigate the trimester-specific associations between maternal total physical activity level vs moderate-to-vigorous exercise and fetal growth disorders.

METHODS

We analyzed 2062 mother-neonate pairs participating in the longitudinal China Medical University Birth Cohort Study. The Pregnancy Physical Activity Questionnaire was used to assess the physical activity level of women during the three trimesters. A higher level of total physical activity was defined as meeting or exceeding the cohort-specific 75th percentile, and a higher level of exercise was defined according to the Physical Activity Guidelines for Americans. Fetal growth disorder was defined as small-for-gestational age (SGA) or large-for-gestational age (LGA) at birth.

RESULTS

Of the neonates included in this study, 7.1% were SGA and 15.5% were LGA. A higher level of total physical activity during the first trimester (adjusted relative risk (aRR), 0.62 (95% CI, 0.42-0.91)) and second trimester (aRR, 0.62 (95% CI, 0.41-0.95)) was associated with a lower risk of SGA, and a higher level of total physical activity during the third trimester was associated with a lower risk of LGA (aRR, 0.73 (95% CI, 0.54-0.97)). When analyzing physical activity by subtype, a higher level of occupational physical activity during the first and second trimesters was associated negatively with SGA risk, and higher levels of occupational and low-intensity physical activity during the first trimester were associated negatively with LGA risk. No significant association was found between maternal adherence to the Physical Activity Guidelines for Americans and risk of fetal growth disorders.

CONCLUSIONS

A higher total physical activity level during the first and second trimesters was associated with a decreased risk of SGA, whereas a higher total physical activity level in the third trimester was associated with a decreased risk of LGA. Pregnant women should be advised to increase their total physical activity levels instead of focusing on engaging in only moderate-to-vigorous exercise. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Visiting natural open spaces in urban areas during pregnancy and its association with daily physical activity

We examined the association between visiting natural open spaces (NOS) and physical activity (PA) at different trimesters of pregnancy. We used GPS and accelerometer data from women residing in Donostia-San Sebastian and Barcelona. Daily visits to NOS were associated with an increase of circa 8 min of moderate to vigorous physical activity (MVPA) in the first and second trimesters of pregnancy. Women who visited NOS were more likely to meet the WHO daily PA guidelines during the first trimester. Visiting NOS can promote PA consistently during pregnancy, improving maternal health and well-being in urban settings.

Optimizing labor duration with pilates: evidence from a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Pilates has captured interest due to its possible advantages during pregnancy and childbirth. Although research indicates that Pilates may reduce labor duration, alleviate pain, and improve satisfaction with the childbirth experience, consensus on these outcomes remains elusive, underscoring the necessity for additional studies.

AIM

This systematic review and meta-analysis aimed to assess the impact of Pilates exercises on labor duration among pregnant women.

METHODS

The online database was searched to yield the literature using the terms of 'Pilates', 'childbirth', and 'labor duration', and similar terms including PubMed, Clinical Key, Scopus, Web of Science, Embase, and Cochrane Database of Systematic Reviews up to June 25, 2023. Studies were considered eligible if they were randomized or clinical controlled trials (RCTs/CCTs) published in English, focusing on healthy pregnant women without exercise contraindications. The studies needed to include interventions involving Pilates or exercise movement techniques, a comparison group with no exercise, and outcomes related to labor duration, the period of the active phase, and the second stage of delivery.

RESULTS

Eleven studies, totalling 1239 participants, were included in the analysis. These studies provided high-quality evidence from exercise only RCTs/CCTs. The findings indicated a significant reduction in the active phase of labor (8 RCTs, n = 1195; Mean Difference [MD] = -56.35, 95% Confidence Interval [CI] [-89.46 to -23.25]) and overall labor duration (8 RCTs, n = 898; MD = -93.93, 95% CI [-138.34 to -49.51]) in pregnant women who engaged in Pilates exercises compared to those who did not but doesn't affect on the duration of the second stage of labor (7 RCTs, n = 1135; MD = -0.11, 95% CI [-7.21 to 6.99]).

CONCLUSIONS

While this review primarily addresses the effects of Pilates on healthy and low-risk pregnant women, the findings suggest a potential role for Pilates in shortening labor duration. Therefore, engaging in Pilates or similar physical activities is recommended for pregnant women to potentially facilitate a more efficient labor process.

The effectiveness of integrated online health-coaching on physical activity and excessive gestational weight gain: a prospective randomized-controlled trial

PURPOSE

Low levels of physical activity during pregnancy go along with increased risks for numerous health complications. We investigated whether an integrated lifestyle intervention leads to higher levels of physical activity and reduces the rate of excessive gestational weight gain (EGWG).

METHODS

We conducted a randomized-controlled trial on 97 pregnant women, randomly assigned to receive an additional telehealth lifestyle intervention (experimental group, EG; n = 49) or conventional antenatal care (control group, CG; n = 48). The core lifestyle intervention comprised regular video calls, providing integrated personal support and motivation to physical activity. The primary outcome was change in physical activity measured in steps per day. An additional exploratory outcome was the proportion of participants with EGWG.

RESULTS

The mean step count during the third trimester was 6483 steps/day (EG) and 5957 steps/day (CG), respectively (p = 0.078). Repeated-measures ANOVA revealed a significant interaction effect (p = 0.045) reflecting an overall increase of 497 steps per day in the EG vs. a decrease of 300 steps per day in the CG. The proportion of participants who met the IOM recommendation for total weight gain during pregnancy was significantly higher in the EG (p = 0.048) and the ratio of women that gained excessively was higher in the CG (p = 0.026).

CONCLUSIONS

We assume that the personalized online intervention supports women in increasing or at least maintaining their level of physical activity during the course of pregnancy. Additionally, it reduces the rate of excessive weight gain.

Prevalence of autism spectrum disorder diagnosis by birth weight, gestational age, and size for gestational age: a systematic review, meta-analysis, and meta-regression

We aimed to comprehensively pool the prevalence of autism spectrum disorder (ASD) diagnosis by birth weight, gestational age, and size for gestational age. PubMed, EMBASE, Web of Science, Ovid PsycINFO, and Cochrane Library were searched up to December 22, 2021. We pooled data using the random-effects model and quantified heterogeneity using the I2 statistic. Of 66 643 records initially identified, 75 studies were included in the meta-analysis. The pooled prevalence estimates of ASD diagnosis are as follows: very-low-birth weight, 3.1% (912 ASD/66,445 individuals); low-birth weight, 2.3% (5672 ASD/593,927 individuals); normal-birth weight, 0.5% (17,361 ASD/2,378,933 individuals); high-birth weight, 0.6% (4505 ASD/430,699 individuals); very preterm, 2.8% (2113 ASD/128,513 individuals); preterm, 2.1% (19 672 ASD/1 725 244 individuals); term, 0.6% (113,261 ASD/15,297,259 individuals); postterm, 0.6% (9419 ASD/1,138,215 individuals); small-for-gestational-age, 1.9% (6314 ASD/796,550 individuals); appropriate-for-gestational-age, 0.7% (21,026 ASD/5,936,704 individuals); and large-for-gestational-age, 0.6% (2607 ASD/635,666 individuals). Compared with the reference prevalence (those in normal-birth weight, term, and appropriate-for-gestational-age individuals), the prevalence estimates of ASD diagnosis in very-low-birth weight, low-birth weight, very preterm, preterm, and small-for-gestational-age individuals increased significantly, while those in high-birth weight, postterm, and large-for-gestational-age individuals did not change significantly. There were geographical differences in the prevalence estimates. This meta-analysis provided reliable estimates of the prevalence of ASD diagnosis by birth weight, gestational age, and size for gestational age, and suggested that low-birth weight (especially very-low-birth weight), preterm (especially very preterm), and small-for-gestational-age births, rather than high-birth weight, postterm, and large-for-gestational-age births, were associated with increased risk of ASD diagnosis. However, in view of marked between-study heterogeneity in most conditions, unknown effects of certain important confounders associated with ASD due to limited information in original articles, and included studies from a relatively small number of countries, the findings of this study should be interpreted with caution.

The Importance of Sleep in Overcoming Childhood Obesity and Reshaping Epigenetics

The development of childhood obesity is a complex process influenced by a combination of genetic predisposition and environmental factors, such as sleep, diet, physical activity, and socioeconomic status. Long-term solutions for decreasing the risk of childhood obesity remain elusive, despite significant advancements in promoting health and well-being in school and at home. Challenges persist in areas such as adherence to interventions, addressing underlying social determinants, and individual differences in response to treatment. Over the last decade, there has been significant progress in epigenetics, along with increased curiosity in gaining insights into how sleep and lifestyle decisions impact an individual's health. Epigenetic modifications affect the expression of genes without causing changes to the fundamental DNA sequence. In recent years, numerous research studies have explored the correlation between sleep and the epigenome, giving a better understanding of DNA methylation, histone modification, and non-coding RNAs. Although significant findings have been made about the influence of sleep on epigenetics, a notable gap exists in the literature concerning sleep-related genes specifically associated with childhood obesity. Consequently, it is crucial to delve deeper into this area to enhance our understanding. Therefore, this review primarily focuses on the connection between sleep patterns and epigenetic modifications in genes related to childhood obesity. Exploring the interplay between sleep, epigenetics, and childhood obesity can potentially contribute to improved overall health outcomes. This comprehensive review encompasses studies focusing on sleep-related genes linked to obesity.

Physically active pregnancies: Insights from the placenta

Physical activity (PA) positively influences pregnancy, a critical period for health promotion, and affects placental structure and function in ways previously overlooked. Here, we summarize the current body of literature examining the association between PA, placenta biology, and physiology while also highlighting areas where gaps in knowledge exist. PA during pregnancy induces metabolic changes, influencing nutrient availability and transporter expression in the placenta. Hormones and cytokines secreted during PA contribute to health benefits, with intricate interactions in pro- and anti-inflammatory markers. Extracellular vesicles and placental "-omics" data suggest that gestational PA can shape placental biology, affecting gene expression, DNA methylation, metabolite profiles, and protein regulation. However, whether cytokines that respond to PA alter placental proteomic profiles during pregnancy remains to be elucidated. The limited research on placenta mitochondria of physically active gestational parents (gesP), has shown improvements in mitochondrial DNA and antioxidant capacity, but the relationship between PA, placental mitochondrial dynamics, and lipid metabolism remains unexplored. Additionally, PA influences the placenta-immune microenvironment, angiogenesis, and may confer positive effects on neurodevelopment and mental health through placental changes, vascularization, and modulation of brain-derived neurotrophic factor. Ongoing exploration is crucial for unraveling the multifaceted impact of PA on the intricate placental environment.

Mediating effect of gestational weight gain on the preventive effect of exercise during pregnancy on macrosomia: a randomized clinical trial

OBJECTIVE

We sought to investigate the impact of individualized exercise guidance during pregnancy on the incidence of macrosomia and the mediating effect of gestational weight gain (GWG).

DESIGN

A prospective randomized clinical trial.

SETTING

A Hospital in Xingtai District, Hebei Province.

POPULATION

Older than 20 years of age, mid-pregnancy, and singleton pregnant women without contraindications to exercise during pregnancy.

METHODS

A randomized clinical trial was conducted from December 2021 to September 2022 to compare the effects of standard prenatal care with individualized exercise guidance on the incidence of macrosomia.

MAIN OUTCOME MEASURE

Incidence of macrosomia.

RESULTS

In all, 312 singleton women were randomized into an intervention group (N = 162) or a control group (N = 150). Participants who received individualized exercise guidance had a significantly lower incidence of macrosomia (3.73% vs. 13.61%, P = 0.002) and infants large for gestational age (9.94% vs. 19.73%, P = 0.015). However, no differences were observed in the rate of preterm birth (1.86% vs. 3.40%, P = 0.397) or the average gestational age at birth (39.14 ± 1.51 vs. 38.69 ± 1.85, P = 0.258). Mediation analysis revealed that GWG mediated the effect of exercise on reducing the incidence of macrosomia.

CONCLUSION

Individualized exercise guidance may be a preventive tool for macrosomia, and GWG mediates the effect of exercise on reducing the incidence of macrosomia. However, evidence does not show that exercise increases the rate of preterm birth or affects the average gestational age at birth.

TRIAL REGISTRATION

The trial is registered at www.clinicaltrails.gov [registration number: NCT05760768; registration date: 08/03/2023 (retrospectively registered)].

The Impact of Medical Physical Training and a Structured Personalized Exercise Training Program on Hemodynamic Parameters and Arterial Stiffness in Pregnant Women

INTRODUCTION

In developed countries, heart disease is the primary cause of maternal mortality during pregnancy. Arterial stiffness, an independent risk factor for atherosclerosis and a predictor of cardiovascular complications, can be assessed using the augmentation index (AIx) and pulse wave velocity (PWV). In this prospective study, we aimed to evaluate diverse hemodynamic parameters and arterial stiffness in pregnant women before and after participating in a structured, personalized exercise training program.

MATERIALS AND METHODS

Forty healthy pregnant women, non-smokers, who agreed to participate daily for 12 weeks in a physical exercise training program under the supervision of a team made up of an obstetrician, a cardiologist, and a physiotherapist were included. Anthropometric characteristics, arterial function, and physical activity data were collected from the participants at two different time points: at the beginning of the exercise training program (T0) and at the end, after 12 weeks (T1).

RESULTS

Upon conducting a statistical analysis, it was discovered that there were noteworthy disparities (p = 0.05) in body mass index, brachial AIx, systolic blood pressure, and pulse pressure values between the two time points. The regression analysis for the AIx brachial values and the PWVao values from Trim II (T0) and Trim III (T1) showed major differences between these two time points; the association between the AIx brachial values in the second and third trimesters of pregnancy revealed a strong direct significant correlation (p < 0.001), and the correlation between the PWVao values in the second (T0) and third trimester (T1) of pregnancy was weak and insignificant (p = 0.12).

CONCLUSIONS

The findings of our study indicate that a personalized exercise training program positively impacts the physical and psychological well-being of pregnant women, leading to a reduction in PWV.

Exercise FITT-V during pregnancy: Association with birth outcomes

BACKGROUND

Prenatal exercise improves birth outcomes, but research into exercise dose-response effects is limited.

METHODS

This study is a retrospective, secondary analysis of pooled data from three blinded, prospective, randomized controlled trials. Prenatal exercise frequency, intensity, type, time, and volume (FITT-V) were assessed in supervised sessions throughout pregnancy. Gestational age (GA), neonatal resting heart rate (rHR), morphometrics (body circumferences, weight-to-length and ponderal index) Apgar and reflex scores, and placental measures were obtained at birth. Stepwise regressions and Pearson correlations determined associations between FITT-V and birth outcomes.

RESULTS

Prenatal exercise frequency reduces ponderal index (R2 = 0.15, F = 2.76, p = .05) and increased total number of reflexes present at birth (R2 = 0.24, F = 7.89, p < .001), while exercise intensity was related to greater gestational age and birth length (R2 = 0.08, F = 3.14; R2 = 0.12, F = 3.86, respectively; both p = .04); exercise weekly volume was associated with shorter hospital stay (R2 = 0.24, F = 4.73, p = .01). Furthermore, exercise type was associated with placenta size (R2 = 0.47, F = 3.51, p = .01).

CONCLUSIONS

Prenatal exercise is positively related to birth and placental outcomes in a dose-dependent manner.

Medical issues for female athletes returning to competition after childbirth

BACKGROUND

In recent years, the number of athletes who aim to return to competition after childbirth has increased. However, few international reports have investigated complications during pregnancy, and changes in physical function after childbirth in many athletes.

OBJECTIVE

To conduct a retrospective investigation of medical problems during pregnancy, and postpartum, in female athletes who aim to return to competition after childbirth, and to identify the barriers and facilitators for their return.

METHODS

A voluntary web-based survey was aimed at former female athletes who became pregnant with their first child and gave birth during their active sports career. The survey items included respondent background, their exercise activities during and after childbirth, perinatal complications, mode of delivery, symptoms and physical function after childbirth. The participants were divided into a vaginal delivery group and a cesarean section group.

RESULTS

Three hundred and twenty-eight (29.1 ± 5.1 years old) former athletes were included in the analysis, and about half reported undertaking exercise during pregnancy. The most common perinatal complication was anemia (27.4%). The appearance of any symptoms after childbirth, including low back pain (44.2%) and urinary incontinence (39.9%), was reported by 80.5%. The rate of urinary incontinence may be higher in the vaginal delivery than in the cesarean section group (p = 0.05). The most common physical decline after childbirth was in muscular strength, followed by speed and endurance.

CONCLUSION

Addressing pregnancy-associated anemia and managing low back pain is critical for athletes aiming to return to competition after childbirth. Additionally, interventions to reduce the risk for and treat urinary incontinence are important. In addition, in order to return to competition after childbirth, it is important to strengthen muscles, especially the lower limbs and trunk, as well as to create a training program that takes into account the sport/events.

Fetal growth restriction exhibits various mTOR signaling in different regions of mouse placentas with altered lipid metabolism

Fetal growth restriction (FGR) is a common complication of pregnancy and can have significant impact on obstetric and neonatal outcomes. Increasing evidence has shown that the inhibited mechanistic target of rapamycin (mTOR) signaling in placenta is associated with FGR. However, interpretation of existing research is limited due to inconsistent methodologies and varying understanding of the mechanism by which mTOR activity contributes to FGR. Hereby, we have demonstrated that different anatomic regions of human and mouse placentas exhibited different levels of mTOR activity in normal compared to FGR pregnancies. When using the rapamycin-induced FGR mouse model, we found that placentas of FGR pregnancies exhibited abnormal morphological changes and reduced mTOR activity in the decidual-junctional layer. Using transcriptomics and lipidomics, we revealed that lipid and energy metabolism was significantly disrupted in the placentas of FGR mice. Finally, we demonstrated that maternal physical exercise during gestation in our FGR mouse model was associated with increased fetal and placental weight as well as increased placental mTOR activity and lipid metabolism. Collectively, our data indicate that the inhibited placental mTOR signaling contributes to FGR with altered lipid metabolism in mouse placentas, and maternal exercise could be an effective method to reduce the occurrence of FGR or alleviate the adverse outcomes associated with FGR.

Maternal voluntary physical exercise in the adult rat: evidence of exercise-associated differences in maternal food intake, and in brain effects on the progeny

Objectives: Maternal physical activity may impact behavioral and electrophysiological aspects of brain function, with short- and long-term effects on pre- and postnatal neurodevelopment of the offspring. This study evaluated in the rat the effects of maternal voluntary physical activity (MVPA) on food intake and weight gain in the dams, as well as anxiety-like behavior, short-term memory and the brain excitability-related phenomenon known as cortical spreading depression (CSD) on the mother-pup dyad.Methods: Female Wistar rats (n=33) were individually housed in cages containing a running wheel for a 30-days adaptation period before mating. Rats were classified as inactive (I); active (A) or very active (VA) according to the distance spontaneously travelled daily. During gestation, the dams continued to have access to the running wheel. Mothers and their respective pups (1 pup per mother) were evaluated in the open field test (OFT), object recognition test (ORT), elevated plus maze test (EPMT) and the CSD propagation features.Results: MVPA was directly associated with increased food intake and weight gain during gestation, and maternal anxiolytic-like behavioral responses in the OFT. Pups from VA mothers showed a high discrimination index for shape recognition memory (ORT) and decreased propagation velocities of CSD, when compared with the inactive group.Discussion: The data suggest that MVPA during the gestational period induces neuroplasticity and may modulate the brain functions in the mother-infant dyad in the rat.

Stress is not so bad-cortisol level and psychological functioning after 8-week HIIT program during pregnancy: a randomized controlled trial

Background

Amid extensive pregnancy exercise research, the impact of High Intensity Interval Training (HIIT) on pregnant women's mental health is underexplored. Despite exercise benefits, it can trigger stress responses like elevated cortisol. This study fills the gap by investigating correlations between hair cortisol levels, mental health, and HIIT effects in pregnant women.

Methods

We conducted a randomized control trial among 38 Caucasian women in uncomplicated, singleton pregnancy (age 31.11 ± 4.03 years, 21.82 ± 4.30 week of gestation; mean ± SD). The experimental group comprised 22 women engaged in an 8-week high-intensity interval training program (HIIT). The comparative group consisted of 16 pregnant women undergoing an 8-week educational program (EDU). Before and after the interventions, all women were evaluated using the following tools: Hair cortisol level measurements, Beck Depression Inventory - II for depressive symptoms assessment, Childbirth Attitudes Questionnaire for childbirth fear measurement, 12-item Short Form Health Survey to gage health-related quality of life, International Physical Activity Questionnaire for physical activity level estimation, and a Progressive maximal exercise test to evaluate maternal exercise capacity.

Results

The key finding of our study reveals that women engaged in the HIIT intervention exhibited a distinct cortisol production pattern in contrast to the EDU group practicing standard moderate intensity physical activity. In the HIIT group, there was an increase in hair cortisol levels, while the EDU group showed a notable decrease. Remarkably, HIIT stimulated cortisol production without adversely impacting fear of childbirth and psychophysical condition during pregnancy. In fact, only the HIIT group showed a significant enhancement in mental health.

Conclusion

No links were discovered between hair cortisol levels and the severity of depressive symptoms, psychophysical well-being, or fear of childbirth. Hence, based on our research, employing cortisol levels during pregnancy as an indicator of negative stress or depression risk appears unwarranted.

Monitored home-based with or without face-to-face exercise for maternal mental health during the COVID-19 pandemic

INTRODUCTION

Despite the known beneficial effects of exercise, most pregnant women do not exercise regularly. Most studies on exercise have been conducted on supervised exercise and there is limited evidence regarding the adherence and effect of other exercise programs on pregnancy outcomes. Therefore, we aimed to investigate adherence to a face-to-face plus monitored home exercise program versus a monitored home-based exercise program on its own during pregnancy. In addition, effects of these two exercise programs on women's mental health during pregnancy and postpartum (primary outcomes) and on some other maternal and neonatal outcomes (secondary outcomes) will be assessed.

METHODS

In this superiority trial with three parallel arms, 150 women at 12-18 weeks of gestation will be randomised equally into three groups (face-to-face plus monitored home exercise, only monitored home-based exercise, and control). The exercise programs will be performed up to the 38th week of gestation during which participants will be assessed at specific intervals during the pregnancy, and post-partum and followed up until six months after childbirth. The exercise diary will be used to assess the adherence. The Edinburgh Depression Scale and the Positive and Negative Affect Schedule will be used to assess prenatal and postnatal depression and affect, respectively.

DISCUSSION

This study reflects the feasibility and acceptance of two exercise programs for pregnant women and their effects on important outcomes. If these programs are followed properly and effectively, pregnant women's health can be improved using these methods at a lower cost compared to the conventional supervised exercise program.

Comparative effect of different types of physical exercise and intensity levels on low birth weight: A systematic review and network meta-analysis

BACKGROUND

Low birth weight (LBW) has been established as a major determinant of neonatal mortality and morbidity. However, there is no evidence of the effectiveness of different types of physical exercise (PE) at different intensities during pregnancy to prevent LBW.

OBJECTIVES

To compare the effectiveness of different types of PE at different levels of intensity in pregnant women to prevent LBW.

DESIGN

A systematic review and network meta-analysis was performed according to the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols for Network Meta-Analysis extension statement.

DATA SOURCES AND METHODS

We searched the PubMed, Cochrane Central Register of Controlled Trials, Scopus, and Web of Science databases from inception to November 2023. We included randomized controlled trials (RCTs). A random effects method was used to calculate the pooled mean difference (MD). The effect of each intervention was calculated using a network meta-analysis with a frequentist perspective.

RESULTS

Forty-three RCTs were included in the systematic review, and 38 RCTs were included in the network meta-analysis. In the general population, although no significant results, the MDs for light-moderate strength, moderate-vigorous strength, and moderate-vigorous Pilates exercises were favorable for preventing LBW. Furthermore, moderate-vigorous strength exercise was effective to prevent LBW, reporting significant MD compared to control groups in the healthy population (310.00, 95% confidence interval: 78.40, 541.60; I2 = 81.3%).

CONCLUSION

Strength exercises at a moderate-vigorous intensity could be a potential strategy for the prevention of LBW in the healthy population. However, our findings should be interpreted with caution because the overall risk of bias was between "some concerns" and "high," and the overall certainty of the evidence was low.

REGISTRATION

PROSPERO CRD42023401770.

Influence of Physical Activity during Pregnancy on Neonatal Complications: Systematic Review and Meta-Analysis

Newborn hospitalisations after delivery are indicators of poor neonatal health with potential risks of future diseases for children. Interventions to promote a healthy environment have been used during pregnancy, with physical activity as a principal element. A systematic review and meta-analyses were performed to evaluate the effect of physical activity during pregnancy on neonatal intensive care unit (NICU) admissions and Apgar 1 and 5 scores (Registration No.: CRD42022372493). Fifty studies (11,492 pregnant women) were included. There were significantly different rates of NICU admissions between groups (RR = 0.76, 95% CI = 0.62, 0.93; Z = 2.65, p = 0.008; I2 = 0%, and Pheterogeneity = 0.78), and significant differences in Apgar 1 (Z = 2.04; p = 0.04) (MD = 0.08, 95% CI = 0.00, 0.17, I2 = 65%, Pheterogeneity = 0.00001) and Apgar 5 (Z = 3.15; p = 0.002) (MD = 0.09, 95% CI = 0.04, 0.15, I2 = 80%, and Pheterogeneity = 0.00001), favouring intervention groups. Physical activity during pregnancy could help to reduce the risk of NICU admissions that are related to neonatal complications.

Impact of COVID-19 mandatory lockdown on maternal gestational weight gain and neonatal macrosomia rate at an academic medical center in Israel

BACKGROUND

In an effort to prevent the spread of coronavirus disease 2019 (COVID-19), governments restricted outdoor activities and imposed lockdown quarantine. This change in lifestyle probably affected individuals' eating habits and physical activity.

OBJECTIVE

To examine the effect of lockdown due to the COVID-19 pandemic on maternal antenatal weight gain, neonatal macrosomia, and other maternal and neonatal outcomes of women delivering at an academic medical center in Israel.

METHOD

A retrospective, two-period cohort study conducted at a university teaching medical center in Afula, Israel. The study period was between April and September 2020. This period signifies worsening in pandemic situations, during which citizens experienced strict prolonged lockdown measures. The parallel unexposed period (control period) was between April and September 2019. Singleton pregnancies delivered at >24 weeks were eligible. Primary outcome was incidence of macrosomia. Secondary outcomes included gestational weight gain, body mass index (BMI) at delivery, rates of gestational diabetes mellitus (GDM), mode of delivery, postpartum hemorrhage (PPH), and neonatal outcomes reflecting neonatal birth weight and condition at delivery.

RESULTS

A total of 4,765 women were included, 2,442 in the study group and 2,323 in the control group. The incidence of macrosomia was significantly higher in 2020 (6.2%) than in 2019 (4.9%), (p = .048; OR: 1.29; 95% CI: 1.002- 1.65). Women gained significantly more weight (median 1 kg more), weighed more at delivery (median 1 kg), and had higher BMI at delivery in 2020 compared with those in 2019 (p < .01). The incidence of GDM was 9.5% and 8.5% in the study and control groups respectively (p = .26; OR: 1.12; 95% CI: 0.92-1.37). Greater percentage of women did not perform the glucose challenge test in 2020 (9.9%) compared with those in 2019 (7.5%) (p = .003, OR: 1.36; 95% CI: 1.11-1.67). The incidence of any hypertension related to pregnancy was significantly higher in 2020 compared to 2019 (5.8% vs 4.4% respectively, (p = .042; OR: 1.32; 95% CI: 1.02-1.71). The proportion of women who smoked during pregnancy was also significantly higher in 2020 than in 2019 (5.1% vs 3.7%, respectively, p = .02; OR: 1.40; 95% CI: 1.06-1.86). Delivery mode did not differ, while the incidence of PPH was significantly higher in 2020 than in 2019 (5.6% vs 3.4%, respectively, p = .001; OR: 1.65; 95% CI: 1.25-2.19). Neonatal condition at delivery was comparable.

CONCLUSION

COVID-19-related lockdown was associated with the increased rate of macrosomic infants. This indirect effect of the pandemic is probably related to poorer maternal antenatal metabolic health status. Long-term consequences should be further examined.

Social support for exercise from pregnancy to postpartum and the potential impact of a mobile application: A randomized control pilot trial in Southern United States

This study compared perceived social support among women of all body mass index (BMI) categories with an attempt to assess the efficacy of the BumptUp® mobile application to improve social support for exercise during pregnancy and postpartum. Thirty-five pregnant women living in Southern United States were included in the sample. The intervention group received access to the BumptUp® mobile application that was designed to promote physical activity during pregnancy and postpartum. The control group received an evidence-based educational brochure. Perceived social support for exercise was assessed at four-time points using the social support and exercise survey. Outcomes were evaluated at 23-25, 35-37 gestational weeks, and 6 and 12 weeks postpartum. Based on their pre-pregnancy weight and height, BMI was computed to categorize participants into lean, overweight, and obese groups. Social support across BMI categories and between control and intervention groups were compared using linear mixed-effect models. Women grouped in the overweight and obese BMI categories reported receiving significantly lower levels of social support for exercise than women in the lean category throughout pregnancy and postpartum during mid-pregnancy, late pregnancy, and at 12 weeks postpartum (p < 0.05). Although the intervention group received higher social support than the control group throughout all four assessment points, the difference was not statistically significant (p > 0.05). Women with a pre-pregnancy BMI of overweight and obese received lower social support for exercise during pregnancy and postpartum. The efficacy of BumptUp® to improve perceived social support for exercise in pregnancy and postpartum was not evident in the results.

Metabolomics to Understand Alterations Induced by Physical Activity during Pregnancy

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

Can Pre-Pregnancy Body Mass Index and Maternal Exercise Affect Birth and Neonatal Outcomes-A Cross Sectional Study

There has been a dramatic worldwide increase in the prevalence of obesity or overweight and physical inactivity in women of reproductive age. Growing evidence suggests that pre-pregnancy maternal abnormal body mass index (BMI) and lower physical activity level are associated with poor maternal health and perinatal outcomes. The aim of this study was to assess how self-perceived exercise and pre-pregnancy BMI are associated with preterm birth, low birth weight, and type of birth. We conducted a retrospective cross-sectional study of 394 Polish women in the postpartum period. We used a questionnaire with the structure of the medical interview. To analyze factors related to birth outcomes, we used the Pearson's Chi-squared test of independence and odds ratio (OR), with a corresponding 95% confidence interval (CI), followed by a multiple logistic regression. Women who reported being physically active before pregnancy (p = 0.00) and during pregnancy (p = 0.03) were more likely to give birth on time and had a lower incidence of very-premature and extremely premature births compared to inactive women. Importantly, they were more likely to have vaginal birth (p = 0.03). Pre-pregnancy BMI influenced the week of delivery, i.e., inadequate, too-high BMI contributed to an increase in the percentage of premature births [OR (95% CI) = 1.19 (1.06; 1.34)]. The findings indicate that promoting physical activity and weight management remains a priority in public health policy, and women of childbearing age should be encouraged to adopt or maintain an active and healthy lifestyle during pregnancy in order to avoid sedentary- and obesity-associated risks affecting birth and newborns' health.

Attitudes and Barriers to Physical Activity and Exercise Self-Efficacy Among Chinese Pregnant Women: A Cross-Sectional Study

Background

Most pregnant women do not reach the recommendation for physical activity (PA). As a subcategory of PA, exercise is also essential. Evidence on pregnant women's attitudes and barriers to PA and exercise self-efficacy in China is scarce.

Aim

To explore the levels and influencing factors of attitudes and barriers to PA and exercise self-efficacy among pregnant women.

Methods

A cross-sectional study of 311 pregnant women was conducted from August to December 2022. Individual characteristics, pregnant women's attitudes toward exercise, barriers to prenatal PA and exercise, and exercise self-efficacy were measured using the self-designed demographic questionnaire, pregnant women's attitudes toward exercise questionnaire, barriers to prenatal PA and exercise questionnaire, and the pregnancy exercise self-efficacy scale, respectively.

Results

More than 90% of pregnant women believed exercise benefits themselves and their babies, and 40.8% of pregnant women did not know how to exercise. Women encounter different types of barriers to PA and exercise. Intrapersonal barriers included the proportion of feelings of tiredness (56.6%), low energy (54.7%), lack of interest or motivation (49.2%), feelings of illness and morning sickness (46.6%), and large body weight (43.7%). Interpersonal barriers included pregnant women being advised to avoid PA and exercise (49.2%), lack of clear advice about the intensity and dose of exercise (41.8%), no one to exercise with (38.9%), and lack of advice from healthcare professionals (38.6%). Weather conditions were the most significant environmental barriers (41.2%). The total score of pregnancy exercise self-efficacy was (38.50±7.33). Education level, parity, and attitudes toward exercise independently predict pregnant women's attitudes toward exercise, barriers to prenatal PA and exercise, and exercise self-efficacy, respectively.

Conclusion

Pregnant women have a favorable attitude toward exercise and relatively good exercise self-efficacy but lack knowledge of exercise. They face numerous barriers. Medical professionals should encourage pregnant women with lower levels of education to exercise and assist multipara in overcoming obstacles.

Maternal Exercise Prior to and during Gestation Induces Sex-Specific Alterations in the Mouse Placenta

While exercise (EX) during pregnancy is beneficial for both mother and child, little is known about the mechanisms by which maternal exercise mediates changes in utero. Six-week-old female C57BL/6 mice were divided into two groups: with (exercise, EX; N = 7) or without (sedentary, SED; N = 8) access to voluntary running wheels. EX was provided via 24 h access to wheels for 10 weeks prior to conception until late pregnancy (18.5 days post coitum). Sex-stratified placentas and fetal livers were collected. Microarray analysis of SED and EX placentas revealed that EX affected gene transcript expression of 283 and 661 transcripts in male and female placentas, respectively (±1.4-fold, p < 0.05). Gene Set Enrichment and Ingenuity Pathway Analyses of male placentas showed that EX led to inhibition of signaling pathways, biological functions, and down-regulation of transcripts related to lipid and steroid metabolism, while EX in female placentas led to activation of pathways, biological functions, and gene expression related to muscle growth, brain, vascular development, and growth factors. Overall, our results suggest that the effects of maternal EX on the placenta and presumably on the offspring are sexually dimorphic.

Running from depression: the antidepressant-like potential of prenatal and pre-pubertal exercise in adolescent FSL rats exposed to an early-life stressor

OBJECTIVE

We aimed to answer the questions of whether early-life (perinatal and/or juvenile) exercise can induce antidepressant-like effects in a validated rodent model of depression, and whether such early-life intervention could prevent or reverse the adverse effects of early-life stress in their offspring.

METHODS

Male and female Flinders sensitive line rats born to a dam that exercised during gestation, or not, were either maternally separated between PND02 and 16 and weaned on PND17 or not. Half of these animals then underwent a fourteen-day low-intensity exercise regimen from PND22. Baseline depressive-like behaviour was assessed on PND21 and then reassessed on PND36, whereafter hippocampal monoamine levels, redox state markers and metabolic markers relevant to mitochondrial function were measured.

RESULTS

Pre-pubertal exercise was identified as the largest contributing factor to the observed effects, where it decreased immobility time in the FST by 6%, increased time spent in the open arms of the EPM by 9%. Hippocampal serotonin and norepinephrine levels were also increased by 35% and 26%, respectively, whilst nicotinic acid was significantly decreased.

CONCLUSION

These findings suggest that pre-pubertal low-intensity exercise induces beneficial biological alterations that could translate into antidepressant behaviour in genetically susceptible individuals.

Maternal Exercise during Pregnancy Impacts Motor Performance in 9-Year-Old Children: A Pilot Study

The benefits of maternal physical activity during pregnancy are well documented, but long-term effects on the child have been less studied. Therefore, we conducted a pilot follow-up study of a lifestyle intervention during pregnancy that aimed to investigate whether exercise (endurance and strength training) during pregnancy affects motor performance and body composition of children up to 9 years of age, as well as possible influencing factors like brain-derived neurotrophic factor (BDNF) and lifestyle. Eleven mother-child pairs from the intervention and eight mother-child pairs from the control group were included. From birth up to 9 years of age, no differences in body mass index (BMI) or body mass index standard deviation scores (BMI-SDS) were found between the groups. Lifestyle intervention was one of the influencing factors for children's cardiorespiratory endurance capacity and coordination. Moreover, maternal BDNF in the last trimester was significantly associated with running performance, which may be due to better neuronal development. This is the first study evaluating the effects of a lifestyle intervention during pregnancy on the motor performance 9 years after birth. Children's participation in exercise programs over the past 9 years was not continuously recorded and therefore not included in the analysis. Even a cautious interpretation of these results indicates that a healthy lifestyle during pregnancy is essential in promoting child health. Larger studies and randomized control trials are necessary to confirm our results, especially those pertaining to the role of BDNF.

Strategies used by midwives to support prenatal physical activity: A scoping review

CONTEXT

Despite the well-known benefits of prenatal physical activity for the health of both the mother and her future child, and the existence of international Guidelines for prenatal physical activity, few pregnant women are sufficiently active. Prenatal health care providers, notably midwives, play an important role in promoting prenatal physical activity. Unfortunately, they face several challenges that hinder strategies used to support prenatal physical activity to their clients. The mode of communication used when giving advice and counselling is part of these strategies, as is the content of the information provided. However, little is known about how midwives communicate with their clients when it comes to recommendations about prenatal physical activity, whether it is general or specific recommendations, and about personal factors that may influence their recommendations.

OBJECTIVE

To present a comprehensive analysis of the existing literature on strategies used by midwives to support prenatal physical activity to their clients, focusing on the mode of communication used, the content of the recommendation provided, as well as personal factors that can influence their recommendations.

METHOD

A scoping review was conducted to retrieve original research articles on strategies used by midwives to support prenatal physical activity, published up to May 2023 and available in English and French. The search databases included CINAHL, MEDLINE, Cochrane, Scopus, PubMed, Psychology and behavioural Sciences Collection, and APA PsycINFO. Studies that fulfilled the eligibility criteria were selected for data extraction. The main findings were organized by the mode of communication used (unidirectional and bidirectional) and the type of recommendation provided (general versus specific). Midwives' knowledge, beliefs and attitudes towards prenatal physical activity were also extracted.

RESULTS

A total of 1 307 articles were retrieved and 19 were included. The use of unidirectional mode of communication was identified in 64 %, 64 % and 14 % of the studies when it comes to provide general recommendations, specific recommendations and information on safety, respectively. The use of bidirectional mode of communication was identified in 43 %, 21 % and 7 % of the studies when it comes to provide general recommendations, specific recommendations and information on safety, respectively. Midwives had knowledge gaps about prenatal physical activity, their beliefs were not always aligned with the most recent recommendations, and they sometimes feel vulnerable in the way they support physical activity. However, they expressed the desire to improve the support they are providing.

CONCLUSION

Results of this study highlight that when it comes to support prenatal physical activity, the unidirectional mode of communication is the most often used by midwives. Unfortunately, it is not considered effective as it does not allow discussing and explaining the information provided. Moreover, midwives exhibited some knowledge gaps about prenatal physical activity. Future work will be needed to better understand their challenges and needs in order to improve their initial training and clinical practice.

A narrative review of exercise dose during pregnancy

The current recommendations for prenatal exercise dose align with those from the American College of Sports Medicine; 150 min of moderate intensity every week of pregnancy. However, recent works suggest there may be a dose-dependent beneficial effect for mother and offspring; maternal and offspring health outcomes respond differently to low, medium, and high doses of prenatal exercise. It is, therefore, our aim to summarize the published evidence (years 1950-2023) for five metrics of prenatal exercise training commonly reported, that is, "FITT-V": Frequency (number of sessions), Intensity (metabolic equivalents "METs"), Time (duration of sessions), Type (exercise mode), Volume (exercise MET*mins). The target audience includes clinicians and health care professionals, as well as exercise professionals and physiologists. Data suggest that moderate exercise frequency (3-4 times weekly) appears safe and efficacious for mother and offspring, while there is contradictory evidence for the safety and further benefit of increased frequency beyond 5 sessions per week. Moderate (3-6 METs) and vigorous (>6 METs) intensity prenatal exercise have been shown to promote maternal and offspring health, while little research has been performed on low-intensity (<3 METs) exercise. Exercise sessions lasting less than 1 hr are safe for mother and fetus, while longer-duration exercise should be carefully considered and monitored. Taken together, aerobic, resistance, or a combination of exercise types is well tolerated at medium-to-high volumes and offers a variety of type-specific benefits. Still, research is needed to define (1) the "minimum" effective dose of exercise for mother and offspring health, as well as (2) the maximum tolerable dose from which more benefits may be seen. Additionally, there is a lack of randomized controlled trials addressing exercise doses during the three trimesters of pregnancy. Further, the protocols adopted in research studies should be more standardized and tested for efficacy in different populations of gravid women.

Standardized Stretching Postural postures to treat low-back pain in pregnancy: the GEMALODO randomized clinical trial

BACKGROUND

Two-thirds of pregnant women suffer from low-back pain during pregnancy, which leads to negative effects on quality of everyday life. According to the literature, an 8- to 12-week program of adapted physical activity during pregnancy has proven its efficacy in treatment of low-back pain and functional disability. Stretching Postural is a nondynamic technique using muscular contractions and stretches that act mainly on the back and that can be practiced alone.

OBJECTIVE

This study aimed to assess the effect of an 8-week program of standardized Stretching Postural postures in low-risk pregnant women suffering from low-back pain.

STUDY DESIGN

This was an open-label, randomized, controlled trial in 1 French university hospital. Women with a singleton low-risk pregnancy between 15 and 32 weeks of gestation and with back, lumbar, or sacroiliac pain were randomly assigned (1:1) to either undergo an 8-week program of standardized Stretching Postural with basic advice (intervention group) or to receive basic advice only (control group). Both groups received ergonomic advice and encouragement to practice physical activity. The primary endpoint was the pain assessment at 8 weeks (defined by the mean pain level estimated by women in the previous week, scored on a numeric scale from 0 to 10). Secondary endpoints were pain after 4 weeks of follow-up, quality of life (12-item Short Form Survey), satisfaction (Patient Global Impression of Change), and delivery outcomes. The main analysis was intention-to-treat.

RESULTS

From January 2019 to August 2020, 60 women were randomized: 30 were assigned to the intervention group and 30 to the control group. The mean level of pain at 8 weeks was significantly lower in the intervention group than in the control group (1.6±1.4 vs 4.1±2.2; P<.01). The mean 12-item Short Form Survey scores were significantly higher in the posture group than in the control group (Physical Component Score, 45.7±7.8 vs 37.4±8.5; P<.01; Mental Component Score, 54.3±5.8 vs 50.4±7.1; P=.04), and the Patient Global Impression of Change score was also significantly higher (6.1±1.5 vs 3.9±2.3; P<.01). No adverse effects were found.

CONCLUSION

Stretching Postural appears to be a safe and efficient nondrug therapy to treat low-back pain during low-risk pregnancy.

Physical activity and sedentary time across pregnancy and associations with neonatal weight, adiposity and cord blood parameters: a secondary analysis of the DALI study

BACKGROUND/OBJECTIVES

Obesity during pregnancy is associated with neonatal adiposity, which is a risk factor for childhood obesity. Maternal physical activity (PA) and sedentary behaviours during pregnancy might modify this risk. We therefore studied associations between maternal PA and sedentary time (ST) during pregnancy and neonatal anthropometry and cord blood parameters and investigated whether associations differed by offspring sex.

SUBJECTS/METHODS

Participants of the Vitamin D And Lifestyle Intervention for Gestational Diabetes Mellitus Prevention (DALI) study with a BMI  ≥ 29 kg/m2 were analysed as a cohort. Maternal moderate-to-vigorous PA (MVPA) and ST were measured repeatedly with accelerometers across pregnancy. Associations between mean levels and changes in MVPA and ST and birthweight, neonatal adiposity (fat mass (FM)%) and cord blood parameters, including C-peptide, leptin and lipids, were analysed in 213 mother-child pairs with Bayesian multilevel models. Interactions with offspring sex were considered.

RESULTS

Almost all women decreased MVPA levels and increased ST throughout gestation. Both higher maternal mean MVPA and increasing MVPA were associated with lower offspring FM% in males (-0.520%; 95% CI: -1.011%, -0.031% and -4.649%; -7.876%, -1.432% respectively). In female offspring, mean ST was associated with lower cord blood C-peptide (-0.145 µg/l; -0.279 µg/l, -0.005 µg/l). No associations were found with birthweight or other cord blood parameters.

CONCLUSIONS

Maternal MVPA is associated with neonatal fat mass, but not birthweight, in male offspring. Our findings underline the importance of physical activity throughout pregnancy.

Influence of Physical Activity during Pregnancy on Birth Weight: Systematic Review and Meta-Analysis of Randomized Controlled Trials

Birth weight is a marker that is often referred to determine newborn health, potential growth trajectories and risk of future disease. Accordingly, interventions to promote appropriate and healthy birth weight have been extensively studied and implemented in pregnancy. In particular, physical activity in pregnancy is recommended to promote appropriate fetal development and newborn birth weight. This systematic review and meta-analyses aimed to summarize the effect of physical activity during pregnancy specifically from randomized controlled trials on the following outcomes: birth weight, macrosomia, low birth weight, being large for the gestational age, and being small for the gestational age (Registration No.: CRD42022370729). 63 studies (16,524 pregnant women) were included. There was a significant negative relationship between physical activity during pregnancy and macrosomia (z = 2.16; p = 0.03; RR = 0.79, 95% CI = 0.63, 0.98, I2 = 29%, Pheterogeneity = 0.09). No other significant relationships were found. Promoting physical activity during pregnancy may be an opportune time to reduce the risk of future chronic disease, such as obesity, through the prevention of macrosomia and the promotion of appropriate birth weights.

Is Exercise during Pregnancy a Risk for Gestational Age and Preterm Delivery? Systematic Review and Meta-Analysis

Traditionally, one of the primary concerns regarding exercise during pregnancy has been the potential of reducing gestational age and increasing the likelihood of preterm delivery. The aim of this study was to perform a systematic review about the effects of physical activity (PA) during pregnancy on gestational age and preterm delivery. A systematic review and two meta-analyses were performed (Registration No. CRD42022370770). Data sources from online databases were searched up to November 2022. The review exclusively included studies involving pregnant populations and interventions consisting of PA implemented during pregnancy. The primary outcomes analysed were gestational age, measured in weeks, and the occurrence of preterm deliveries. A total of 57 studies were analysed through two independent meta-analyses for the first one, no association was found between moderate exercise during pregnancy and gestational age (Z = 0.45, p = 0.65, ES = 0.08, 95% CI = -0.06-0.04, I2 = 42%, P heterogeneity = 0.001), showing the exercise group had a higher gestational age. In addition, no differences were found between groups in terms of number of preterm deliveries (RR = 0.96, (95% CI = 0.77-1.21, Z = 0.33, p = 0.74; ES = 0.07; I2 = 31%, P heterogeneity = 0.05)). The findings of this study indicate that there is no association between exercise during pregnancy and reduced gestational age or increased risk of preterm delivery in healthy pregnancies.

Body and Fat mass are not Regulated, Controlled, or Defended: An introduction to the Invisible Hand' and 'Competition' Models of Metabolism

This paper presents two inter-dependent frameworks for understanding the etiology of obesity and the regain of body and fat mass after weight loss. The 'Invisible Hand of Metabolism' illustrates how physiologic states such as body and fat mass and blood glucose levels arise from the unregulated, uncontrolled, yet competitive behavior of trillions of semi-autonomous cells. The 'Competition Model of Metabolism' is an explanatory (mechanistic) framework that details how organismal and cell-specific behaviors generate the apparent stability of physiologic states despite metabolic perturbations (e.g., weight-loss and exercise). Together, these frameworks show that body and fat mass and blood glucose levels are not regulated, controlled, or defended but emerge from the complexity and functional plasticity of competitive cellular relations. Therefore, we argue that the use of abstract constructs such as 'regulation', 'control', 'glucostats', 'adipostats', and 'set-/settling-points' hinders the understanding of obesity and cardiometabolic diseases in human and nonhuman mammals.