Exercise and pregnancy in recreational and elite athletes: 2016 evidence summary from the IOC expert group meeting, Lausanne. Part 2-the effect of exercise on the fetus, labour and birth

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.

Advancing gender equity in sport: a scoping review of international sport federation policies for pregnant, postpartum and parenting elite athletes

OBJECTIVE

The aim was to synthesise international-level sport policies for pregnant, postpartum or parenting high-performance athletes in order to understand what policies currently exist and to identify policy gaps to be addressed.

DESIGN

Scoping review.

DATA SOURCES

Online databases (MEDLINE, EMBASE, CINAHL, SPORTDiscuss, Evidence-Based Medicine Reviews (Ovid), Scopus, Web of Science and ClinicalTrials.gov) and Google up to 14 June 2024. Additionally, a targeted search of existing policies was conducted via the websites of International Federations (IFs) and continental sporting organisations (CSOs) in September 2023.

ELIGIBILITY CRITERIA

We included policies from IFs recognised by the International Olympic Committee, and CSOs associated with the IFs that specifically address pregnant, postpartum or parenting athletes. Policies were a written principle of action adopted by the IFs/CSOs that provided any form of support during pregnancy, post partum or for parents.

RESULTS

A total of 219 organisations (49 IFs; 170 CSOs) were identified and contacted, with 47/49 (96%) IFs and 15/170 (9%) CSOs responding. Sport policies related to pregnancy, postpartum or parenting athletes were identified from 20 IFs including (1) guidance on training/competition during and following pregnancy; (2) eligibility affected or training not advised; (3) protection from dismissal; (4) special rank, points or quota protection; (5) protections apply to adoption, surrogacy, miscarriage, stillbirth, egg freezing and/or fertility treatment; (6) duration of leave and if leave is paid and (7) breastfeeding support/space. No policies identified specific provisions for childcare support/space.

CONCLUSIONS

Less than half of all IFs have developed sport policies to support pregnant, postpartum and parenting athletes. Of the policies that do exist, most are limited in the extent to which they address the broad range of biopsychosocial supports that are necessary for facilitating optimal performance, enhancing long-term athlete health and addressing gender inequities that are deeply entrenched across all levels of sport. This review provides a critical piece of evidence needed to inform future policy development.

The Translation of Policy to Person: A Qualitative Analysis of Elite Athletes' Perceptions of Pregnancy in the United Kingdom

BACKGROUND

An increasing number of female athletes are navigating an athletic career alongside pregnancy. Limited qualitative research has investigated the experiences of elite athletes in the United Kingdom (UK). This study aimed to explore the experiences of elite athletes in the UK as they navigated pregnancy, employing a socio-ecological framework to inform future research and policy recommendations on sport participation during pregnancy.

METHODS

A descriptive qualitative study design, adopting a relativist ontology and constructivist epistemology, was implemented. Semi-structured online interviews were conducted with elite athletes ≥ 18 years old, who resided in the UK, and who trained and/or competed at the highest level of their sport prior to and/or during pregnancy. Interviews were recorded, transcribed and analysed using reflexive thematic analysis.

RESULTS

Eleven athletes (mean age 31 ± 3 years) from nine team and individual sports participated in the study. Four key themes were developed: (1) From the Podium to Parenthood: Institutional versus Individual Influence on Reproductive Planning; (2) Is My Career Over? Micro Level Support versus Macro Level Doubt and Worry; (3) Athlete to Mother: Internal Conflict to Community Role Model; (4) Navigating the Bump: Individual Drive to Tackle Systemic Gaps.

CONCLUSIONS

Findings highlight the complexity female athletes face when navigating pregnancy, motherhood and elite sport. There is a need for high-quality research focusing on preconception and pregnancy-specific training and nutrition modifications for elite athletes, particularly regarding nutrient intake and supplementation. Additionally, efforts to improve the translation of evidence-based research into practical applications remain essential.

"It's unrealistic": experiences of Swedish elite female ice hockey players considering parenthood

Introduction

The number of elite female athletes combining athletic careers with mothering has increased during the last decades. Many mother-athletes return to an equal or an even better level of performance postpartum. Despite numerous success stories across a variety of sports, there are currently no mother-athletes in Swedish elite ice hockey. Therefore, the aim of this study was to explore how Swedish elite female ice hockey players perceive challenges associated with initiating and maintaining the mother-athlete role.

Methods

Qualitative data were collected through semi-structured interviews with 7 elite female ice hockey players (5 prepregnancy and 2 mothers/former athletes) and analyzed using thematic analysis.

Results

Thematic analysis revealed three main challenges facing elite female ice hockey players: (a) Making ends meet, (b) A leap in the dark and (c) You can't be what you can't see. Due to these challenges, the participants perceived combining elite ice hockey and mothering as unrealistic. Consequently, they felt forced to either retire from elite sports early or postpone mothering to post career.

Discussion

Continued work with improving the financial support and developing clear maternity policies is essential to prevent early dropouts before elite female ice hockey players have reached peak performance. Enabling more players to prolong their athletic careers during pregnancy and postpartum will likely produce more positive mother-athlete role models. Further, keeping more players in the sport for a longer period could help women's ice hockey to develop to its highest optimal quality (e.g., level and competition).

Centering the female athlete voice in a sports science research agenda: a modified Delphi survey with Team USA athletes

OBJECTIVES

To co-construct a sports medicine and exercise science research and translational agenda with Team USA elite female athletes serving as the experts on their health, performance and well-being.

METHODS

40 Team USA female athletes across sports disciplines participated in an online, anonymous, modified Delphi survey by ranking topics on a Likert scale (1='strongly disagree' and 5='strongly agree') and providing qualitative justification regarding whether they believed having more information and research on each topic would support their athletic performance, health and well-being. After each Delphi round, quantitative rankings of topics and qualitative justifications were analysed, informing revisions to the list of topics for review in the subsequent round. Researchers provided athletes with a detailed report of findings and revisions following each round.

RESULTS

The final list contained 14 ranked topics. The top five were menstrual cycle symptoms (4.58±0.74), recovery (4.58±0.59), birth control (4.55±0.89), mental health (4.50±0.55) and fueling and the menstrual cycle (4.43±0.74). New topics originating from athletes included recovery, menstrual cycle symptoms, fueling and the menstrual cycle, mental health and sports performance, team dynamics, and institutionalised sexism.

CONCLUSION

This is the first study to co-construct a research and translational agenda with Team USA elite female athletes. The list of sports science research topics developed by focusing on elite female athletes' voices lays the foundation for future research and provides valuable insight into the specific needs of female athletes.

New Public Health and Sport Medicine Institutions Guidelines of Physical Activity Intensity for Pregnancy-A Scoping Review

Background: Before starting PA, pregnant women should select the appropriate type of training and adjust its components to the development of pregnancy and her capabilities. This review aimed to analyze current recommendations for pregnant women on methods for determining and assessing PA intensity levels and characterize the extent and nature of the information provided to pregnant women in official documents published by public health and sports medicine institutions. Methods: The review was conducted as per the PRISMA Extension for Scoping Reviews (PRISMA-ScR). We searched scientific databases (PubMed, ScienceDirect, Web of Science, Academic Search Complete, and SPORTDiscus with Full Text via EBSCO) and the Internet to identify papers regarding recommendations for the PA intensity level for pregnant women. We analyzed 22 eligible guidelines, published over the last 10 years in English, from nine countries and three international organizations. Results: The PA of pregnant women should be at a moderate level. As for higher levels, the analyzed recommendations are contradictory. Methods for assessing PA intensity levels are often not included. The most frequently recommended methods for determining and assessing the PA intensity level for pregnant women are the rating of perceived exertion, the Talk Test, and heart rate measurements. Few guidelines offer specific advice for highly active women (e.g., elite athletes) or trimester-specific considerations. Conclusions: The number of published recommendations regarding PA during pregnancy has increased over the last decade. The amount of information on PA intensity levels is still insufficient. There is a need to update them, based on high-quality scientific work.

Clinical and exercise professional opinion of return-to-running readiness after childbirth: an international Delphi study and consensus statement

Female athletes have identified a lack of guidance as a barrier to successfully returning to running postpartum, and existing guidelines are vague. Our aim was to define the current practice of determining postpartum run-readiness through a consensus survey of international clinicians and exercise professionals in postpartum exercise to assist clinicians and inform sport policy changes.A three-round Delphi approach was used to gain international consensus from clinicians and exercise professionals on run-readiness postpartum. Professionals who work with postpartum runners participated in an online survey to answer open-ended questions about the following postpartum return-to-running topics: definitions (runner and postpartum), key biopsychosocial milestones that runners need to meet, recommended screening, timeline to initiate running, support items, education topics and factors that contribute to advising against running. Consensus was defined as ≥75% participant agreement.One hundred and eighteen professionals participated in round I, 107 participated in round II (response rate 90.6%) and 95 participated in round III (response rate 80.5%). Responses indicated that, following a minimum 3-week period of rest and recovery, an individualised timeline and gradual return to running progression can be considered. Screening for medical and psychological concerns, current physical capacity, and prior training history is recommended prior to a return to running.This study proposes recommendations for the initial guidance on return-to-running postpartum, framed in the context of current research and consensus from professionals. Future research is needed to strengthen and validate specific recommendations and develop guidelines for best practice when returning-to-running after childbirth.

Maternal physical activity, sitting, and risk of non-cardiac birth defects

BACKGROUND

The relationship between maternal physical activity (PA)/sitting and birth defects is largely unexplored. We examined whether pre-pregnancy PA/sitting were associated with having a pregnancy affected by a birth defect.

METHODS

We used data from two United States population-based case-control studies: 2008-2011 deliveries from the National Birth Defects Prevention Study (NBDPS; 9 states) and 2014-2018 deliveries from the Birth Defects Study To Evaluate Pregnancy exposureS (BD-STEPS; 7 states). Cases with one of 12 non-cardiac birth defects (n = 3798) were identified through population-based registries. Controls (n = 2682) were live-born infants without major birth defects randomly sampled using vital/hospital records. Mothers self-reported pre-pregnancy PA/sitting. Unconditional logistic regression models estimated associations between PA/sitting categories and the 12 birth defects.

RESULTS

Mothers engaging in pre-pregnancy PA was associated with a reduced odds of five (spina bifida, cleft palate, anorectal atresia, hypospadias, transverse limb deficiency) and a higher odds of two (anencephaly, gastroschisis) birth defects. Mothers spending less time sitting in pre-pregnancy was associated with a reduced odds of two (anorectal atresia, hypospadias) and a higher odds of one (cleft lip with or without cleft palate) birth defect.

CONCLUSIONS

Reasonable next steps include replication of these findings, improved exposure assessment, and elucidation of biologic mechanisms.

IMPACT

Using data from two population-based case-control studies, we found that mothers engaging in different types of physical activity in the 3 months before pregnancy had an infant with a reduced odds of five and a higher odds of two birth defects. Mothers spending less time sitting in the 3 months before pregnancy had an infant with a reduced odds of two and a higher odds of one birth defect. Clarification and confirmation from additional studies are needed using more precise exposure measures, distinguishing occupational from leisure-time physical activity, and elucidation of mechanisms supporting these associations.

Filling the evidence void: exploration of coach and healthcare provider experiences working with pregnant and postpartum elite athletes - a qualitative study

OBJECTIVE

Recent research grounded in the experiences of elite female athletes has shed light on the complex challenges of navigating sport environments that do not support or value pregnant or postpartum athletes. The purpose of this study was to explore the unique experiences of coaches and healthcare providers working with pregnant and postpartum elite athletes, and to identify actionable steps for research, policy and culture change to support them.

METHODS

Sixteen participants (five coaches, three physicians and eight physiotherapists), who have worked with pregnant and/or postpartum elite athletes within the last 5 years, participated in this qualitative study. Thirteen participants self-identified as women, and three as men. Data were generated via semistructured one-on-one interviews that were audiorecorded, transcribed verbatim and analysed through a process of content analysis.

RESULTS

The findings of this research are represented by five main themes: (a) lack of female athlete reproductive research, (b) need for evidence-informed education and training, (c) need to develop evidence-based progression for sport participation in pregnancy and postpartum, (d) open communication to support athlete-centred care and (e) essential supports and changes required for pregnant/postpartum athletes.

CONCLUSION

Findings from this study, which are grounded in the unique perspectives of coaches and healthcare providers, outline specific recommendations to inform policy and practices that support athletes through the perinatal period, such as developing evidence-based return-to-sport protocols.

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.

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.

Female athlete health domains: a supplement to the International Olympic Committee consensus statement on methods for recording and reporting epidemiological data on injury and illness in sport

The IOC made recommendations for recording and reporting epidemiological data on injuries and illness in sports in 2020, but with little, if any, focus on female athletes. Therefore, the aims of this supplement to the IOC consensus statement are to (i) propose a taxonomy for categorisation of female athlete health problems across the lifespan; (ii) make recommendations for data capture to inform consistent recording and reporting of symptoms, injuries, illnesses and other health outcomes in sports injury epidemiology and (iii) make recommendations for specifications when applying the Strengthening the Reporting of Observational Studies in Epidemiology-Sport Injury and Illness Surveillance (STROBE-SIIS) to female athlete health data.In May 2021, five researchers and clinicians with expertise in sports medicine, epidemiology and female athlete health convened to form a consensus working group, which identified key themes. Twenty additional experts were invited and an iterative process involving all authors was then used to extend the IOC consensus statement, to include issues which affect female athletes.Ten domains of female health for categorising health problems according to biological, life stage or environmental factors that affect females in sport were identified: menstrual and gynaecological health; preconception and assisted reproduction; pregnancy; postpartum; menopause; breast health; pelvic floor health; breast feeding, parenting and caregiving; mental health and sport environments.This paper extends the IOC consensus statement to include 10 domains of female health, which may affect female athletes across the lifespan, from adolescence through young adulthood, to mid-age and older age. Our recommendations for data capture relating to female athlete population characteristics, and injuries, illnesses and other health consequences, will improve the quality of epidemiological studies, to inform better injury and illness prevention strategies.

Effect of Pregnancy in 42 Elite to World-Class Runners on Training and Performance Outcomes

PURPOSE

The International Olympic Committee expert group on pregnancy has identified a paucity of information regarding training and performance in truly elite athletes. Thus, the purpose of this study was to quantify elite runners' training volume throughout pregnancy and postpartum competition performance outcomes.

METHODS

Forty-two elite (>50% competed at the World Championships/Olympic) middle-/long-distance runners' training before, during, and after pregnancy (quality/quantity/type) data (retrospective questionnaire) and competition data (published online) were collected.

RESULTS

Running volume decreased significantly ( P < 0.01) from the first trimester (63 ± 34 km·wk -1 ) to the third trimester (30 ± 30 km·wk -1 ). Participants returned to activity/exercise at ~6 wk postpartum and to 80% of prepregnancy training volumes by 3 months. Participants who intended to return to equivalent performance levels postpregnancy, there was no statistical decrease in performance in the 1 to 3 yr postpregnancy compared with prepregnancy, and ~56% improved performances postpregnancy.

CONCLUSIONS

This study features the largest cohort of elite runners training and competition outcomes assessed throughout pregnancy, with training volumes being approximately two to four times greater than current guidelines. For the first time, performance was directly assessed (due to the quantifiable nature of elite running), and study participants who intended to return to high-level competition did so at a statistically similar level of performance in the 1- to 3-yr period postpregnancy. Taken together, this article provides much needed insights into current training practices and performance of elite pregnant runners, which should help to inform future training guidelines as well as sport policy and sponsor expectations around return to training timelines and performance.

We're not Superhuman, We're Human: A Qualitative Description of Elite Athletes' Experiences of Return to Sport After Childbirth

BACKGROUND

A growing number of athletes return to elite sport following childbirth. Yet, they face significant barriers to do so safely and successfully. The experiences of elite athletes returning to sport following delivery are necessary to support evidence-informed policy.

OBJECTIVE

The purpose of this qualitative description was to describe the experiences of elite athletes as they returned to sport following childbirth, and to identify actionable steps for research, policy and culture-change to support elite athlete mothers.

METHODS

Eighteen elite athletes, primarily from North America, who had returned to sport following childbirth in the last 5 years were interviewed. Data were generated via one-on-one semi-structured interviews that were audio-recorded, transcribed verbatim, and analyzed through a process of content analysis.

RESULTS

The findings of this study are represented by one overarching theme: Need for More Time, and five main themes: (a) Training "New Bodies" Postpartum, (b) Injuries and Safe Return to Sport, (c) Breastfeeding While Training, (d) Critical Supports for Return to Sport, (e) Navigating Motherhood and Sport. The athletes identified the urgent need to develop best-practice policies and funding to support return to sport, as well as develop evidence-based return-to-sport protocols to support a safe and injury-free return.

CONCLUSION

Athletes shared detailed stories highlighting the challenges, barriers and successes elite athletes experience returning to elite-level sport following childbirth. Participants provided clear recommendations for policy and research to better support the next generation of elite athlete mothers.

Longitudinal association of physical activity during pregnancy with maternal and infant outcomes: Findings from the Australian longitudinal study of women's health

BACKGROUND

Physical activity has known benefits during pregnancy; however, the optimum volume of physical activity through the different stages of pregnancy is not well known.

OBJECTIVES

The aims of this study were to investigate the associations of physical activity volume in pregnant women in each trimester of pregnancy with maternal and infant outcomes.

DESIGN

The study involved 1657 pregnant women from the Australian Longitudinal Study on Women's Health, who completed surveys from 2006 to 2012 (aged 28-39 years).

METHODS

Women reported being in either the first, second or third trimester of pregnancy. Women were grouped into four groups according to their self-reported physical activity during pregnancy: (1) Nil (0-<33.3 MET.min/week), (2) Low (33.3-<500 MET.min/week), (3) Moderate (500-<1000 MET.min/week) and (4) High (⩾1000 MET.min/week). Women who reported their physical activity during pregnancy completed a survey within three years after the birth, relating to outcomes associated with pregnancy and childbirth (gestational diabetes, hypertension, and antenatal depression and anxiety) and infant outcomes (birthweight and prematurity).

RESULTS

There was no association of physical activity in any trimester with infant birthweight, prematurity, gestational diabetes, hypertension or antenatal depression. Antenatal anxiety was less prevalent in women who reported low (1.7%) or moderate (1.1%) physical activity than in those who reported no activity (4.7%; p = 0.01).

CONCLUSION

Different amounts of physical activity during pregnancy were not associated with the measured adverse health outcomes. However, low and moderate amounts of physical activity were associated with reduced incidence of antenatal anxiety.

Sport and exercise recommendations for pregnant athletes: a systematic scoping review

Objectives

To analyse the available evidence and identify gaps in current knowledge regarding physical activity volume and intensity and their effects on pregnancy outcomes in female athletes.

Design

Scoping review.

Data sources

A structured literature search of three electronic databases (Embase, PubMed and Web of Science) was conducted on 25 February 2022, and a rerun search was conducted on 8 September 2022.

Eligibility criteria

Studies were eligible if they contained information on the relevant population (ie, elite or competitive amateur female athletes), intervention/exposure (ie, minimum of 10 hours of sport per week) and fetal and maternal outcomes. Eligible comparators included female recreational athletes and pregnant non-exercisers.

Risk of bias

The risk of bias was evaluated with the National Institutes of Health (National Heart, Lung and Blood Institute) quality assessment tool.

Results

The results revealed a discrepancy between the number of original research papers and the number of reviews and recommendations derived from them. The identified studies focused primarily on pregnant recreational athletes. Sixteen clinical studies met the inclusion criteria. No adverse effects on maternal or fetal outcomes were reported. Only during performance tests involving acute intensive exercise with the mother exercising at more than 90% of her maximal heart rate did some fetuses experience decelerations in heart rate.

Summary/conclusion

A lack of high-quality studies and direct evidence on pregnant elite and competitive amateur female athletes is evident. Further prospective observational cohort studies are needed using new monitoring methods (eg, non-invasive, wireless monitoring systems) aiming to gain a broader understanding of the stress tolerance of pregnant athletes and fetuses during exercise. Following that, interventional studies with stress tests in laboratory settings should be conducted. Therefore, technology plays a decisive role in gaining new knowledge and providing evidence-based recommendations on this topic.

PROSPERO registration number

CRD42022309541.

Comparison of First Childbirth Characteristics between Elite Judo Athletes and Non-Athletes: The Preliminary Retrospective Case-Control Study

It has been speculated that elite athletes are more likely to have obstetric interventions during labor and delivery. So far, the impact of many years of competitive sports participation on childbirth characteristics has not been well-established. This preliminary retrospective case-control study aimed to determine whether the first labors of elite judo competitors required obstetric interventions more frequently and were longer than those of non-athletes. The study comprised 32 parous women: 16 elite judo athletes and 16 non-athletes. Women were included if they had access to the following obstetric data (from their first childbirth hospital discharge reports and/or first child's health record books): induction and augmentation of labor, mode of delivery, the duration of labor and its second stage, episiotomy, perineal tear, and the neonate's Apgar score. Electronic surveys were completed concerning childbirth characteristics, level of "eliteness" (judo athletes), and recreational physical activity (non-athletes). The statistical analysis showed no significant between-group differences in any of the first childbirth outcomes under analysis. The preliminary results indicate elite judo practice before first pregnancy had no negative impact on the rates of labor induction and augmentation, delivery mode, duration of labor, the rates of episiotomy and perineal tear, and the neonate's Apgar score. Due to the small sample size, the conclusions should be considered with caution.

Exercise interventions for weight management during pregnancy and up to 1 year postpartum among normal weight women and women with overweight and obesity: An updated systematic review

Background

Given the increased occurrence of pre-gravid obesity in recent years, and the implications of maternal obesity for maternal and offspring health, it is evident that there is a continued need to investigate antenatal and postnatal weight management strategies and to provide evidence-based advice for exercise-based interventions. Given the small number of studies (n = 5) included in an original systematic review by our group in 2015, it was important to add to the dataset by assessing data published since 2015, in order to provide a more in-depth view of current knowledge.

Objective

To provide an updated systematic review on studies employing exercise interventions for weight management in pregnant and postpartum women.

Methods

A systematic review of randomised controlled trials evaluating the effects of an exercise intervention on gestational weight gain and postpartum weight management in normal weight women, and women with overweight and obesity was conducted. PubMed, Scopus, Central Register of Controlled Trials and Web of Science were searched for studies published between September 2013 and June 2021. No restrictions were set on type, intensity, duration, or frequency of exercise intervention. Only studies that targeted body weight or mass as a primary outcome were included.

Results

Thirteen studies were included in this review: 11 during and two following pregnancy. Exercise significantly reduced gestational weight gain in five of the pregnancy studies and induced significant weight loss in one of the postpartum studies. Across studies, there were large disparities in exercise modality, frequency, and duration, although moderate intensity exercise was consistently employed.

Conclusions

Some studies showed positive effects of exercise on weight management during and following pregnancy. While there is still no consensus on effective exercise intervention approaches, it is crucial that physical activity, of any safe form, is recommended to encourage healthy weight management during this time.

Maximizing Recovery in the Postpartum Period: A Timeline for Rehabilitation from Pregnancy through Return to Sport

Increased participation and duration in sport has become commonplace for women with their involvement often including the transition to motherhood in the peak of their athletic careers. No rehabilitation models that assess the full spectrum of pregnancy to postpartum have been developed for women to assist in safe exercise progressions that reduce postpartum symptoms and optimize performance during the return to full activity. Referral to physical therapy both in the prenatal and postnatal period is currently not considered standard of care to reduce prevalence of symptoms such as musculoskeletal pain, diastasis recti, and pelvic floor dysfunction which may ultimately interfere with physical activity and performance. This commentary presents a timeline and suggested progression for exercise participation to improve awareness of the musculoskeletal changes that occur after labor and delivery. The concepts covered may increase the understanding of how to manage pregnant and postpartum athletes from a musculoskeletal perspective and serve as a starting point for establishing appropriate and guided rehabilitation for safe return to sport after childbirth.

Sports Obstetrics: Implications of Pregnancy in Elite Sportswomen, a Narrative Review

Increasing numbers of females are participating in elite sports, with a record number having competed at the Tokyo Olympic Games. Importantly, the ages of peak performance and fertility are very likely to coincide; as such, it is inevitable that pregnancy will occur during training and competition. Whilst there is considerable evidence to promote regular exercise in pregnancy, with benefits including a reduction in hypertensive disorders, gestational diabetes, and reduced rates of post-natal depression, few studies have been conducted which include elite athletes. Indeed, there are concerns that high-intensity exercise may lead to increased rates of miscarriage and preterm labour, amongst other pregnancy-related complications. There is minimal guidance on the obstetric management of athletes, and consequently, healthcare professionals frequently adopt a very conservative approach to managing such people. This narrative review summarises the evidence on the antenatal, intrapartum, and postpartum outcomes in elite athletes and provides recommendations for healthcare providers, demonstrating that generally, pregnant athletes can continue their training, with a few notable exceptions. It also summarises the physiological changes that occur in pregnancy and reviews the literature base regarding how these changes may impact performance, with benefits arising from pregnancy-associated cardiovascular adaptations at earlier gestations but later changes causing an increased risk of injury and fatigue.

Physiological mechanisms of the impact of heat during pregnancy and the clinical implications: review of the evidence from an expert group meeting

Many populations experience high seasonal temperatures. Pregnant women are considered vulnerable to extreme heat because ambient heat exposure has been linked to pregnancy complications including preterm birth and low birthweight. The physiological mechanisms that underpin these associations are poorly understood. We reviewed the existing research evidence to clarify the mechanisms that lead to adverse pregnancy outcomes in order to inform public health actions. A multi-disciplinary expert group met to review the existing evidence base and formulate a consensus regarding the physiological mechanisms that mediate the effect of high ambient temperature on pregnancy. A literature search was conducted in advance of the meeting to identify existing hypotheses and develop a series of questions and themes for discussion. Numerous hypotheses have been generated based on animal models and limited observational studies. There is growing evidence that pregnant women are able to appropriately thermoregulate; however, when exposed to extreme heat, there are a number of processes that may occur which could harm the mother or fetus including a reduction in placental blood flow, dehydration, and an inflammatory response that may trigger preterm birth. There is a lack of substantial evidence regarding the processes that cause heat exposure to harm pregnant women. Research is urgently needed to identify what causes the adverse outcomes in pregnancy related to high ambient temperatures so that the impact of climate change on pregnant women can be mitigated.

Does maternity during sports career jeopardize future athletic success in elite marathon runners?

The impact of maternity (Mat) on subsequent athletic performance is not well known. This study aims to investigate the impact of maternity among elite marathoners on their overall performance progression. For each runner listed in the top 150 female marathoners, who had experienced a mid-career maternity, performance development was reconstituted throughout the career. Maternity data and career break time span (T_total) were collected from publicly available informations. Performances were modelled according to the known age-performance relationship and the impact of maternity was added into the model. Linear mixed effect model was used to study the influence of maternity on the overall career. Among this sample, 37 runners had at least 1 child during her career. Among them, 14 had 2 children. Eleven runners (29.72%) made their personal best performance before Mat, which occurred at an average age of 28.40 ± 4.00 years. Twenty-six runners (70.28%) establish their best performances after Mat, at an average age of 32.20 ± 4.28. The age-performance relationship model explains 92% of the performance variability during the career's progression. When age is considered, maternity does not have significant impact on performance development. World's most competitive marathoners can still perform at their best level after pregnancy. The ability to return and surpass previous performance level is influenced by the age at which pregnancy occurs, relative to the age of peak performance during career development.Highlights Mid-career maternity does not have a significant impact on overall progression in high level runners, who return to official races.The ability to return and surpass previous performance level is influenced by the age at which pregnancy occurs, relative to the age of peak performance.Age is the variable that explains most of performance progression, independently of mid-career maternity occurrence(s).

A Pilot Trial of a Health Promotion and Illness Prevention Paradigm in the Perinatal Period

OBJECTIVES

This is a pilot study of the Vermont Family Based Approach, an innovative health promotion program designed to address behavioral health prevention in primary care, adapted for perinatal women. We aimed to determine the acceptability of the intervention across socioeconomic strata, and to identify if participation improves perinatal mental health.

METHODS

Recruitment occurred at a general obstetrics practice. Women 12-25 weeks gestation were paired with a wellness coach who administered a wellness assessment and used motivational interviewing to facilitate individualized plans based on evidence-based domains of health promotion. Participants were offered access to free, co-located wellness activities through the peripartum, and referred to behavioral health services if appropriate.

RESULTS

93 women consented; 16 Medicaid Insured women (MI) and 30 Privately Insured (PI) were randomized to the intervention. Of all activities, yoga and parenting activities were most appealing, with 58% of women attending. PI (M = 12.30, SD = 11.71) attended significantly more activities than MI (M = 3.81, SD = 12.30; p = .001). Trauma exposure was inversely associated with attendance (p = .004). Randomization to the intervention was not associated with improvements in internalizing symptoms or perceived stress at 12 months postpartum, however, attending three or more wellness activities was associated with a decrease in perceived stress between baseline and 12 months postpartum.

CONCLUSION

This program appeared acceptable and engaging to women with private insurance, but less so with Medicaid. The trial failed to demonstrate improvement in internalizing scores, but of those randomized to the intervention, higher engagement was associated with decreased stress one year after giving birth.

Active Pregnancy: A Physical Exercise Program Promoting Fitness and Health during Pregnancy-Development and Validation of a Complex Intervention

Physical activity during pregnancy is a public health issue. In the view of reproducibility and the successful implementation of exercise interventions, reporting the quality of such study design must be ensured. The objective of this study was to develop and validate a physical exercise program promoting fitness and health during pregnancy. A qualitative methodological study was carried out. For the description of the exercise program, the Consensus on Exercise Reporting Template (CERT) was used. For the validation of the program, the revised guideline of the Criteria for Reporting the Development and Evaluation of Complex Interventions in Health Care (CReDECI2) was followed and went through three stages of development, piloting, and evaluation. The customizable exercise program was designed and validated by exercise and health specialists based on evidence-based, international recommendations and supported by different educational tools to be implemented by qualified exercise professionals in health and fitness settings. A 12-week testing intervention addressing a group of 29 pregnant women was carried out. The program's feasibility was subsequently evaluated by all the pregnant women. The CReDECI2 process guides practitioners and researchers in developing and evaluating complex educational interventions. The presented intervention may assist exercise specialists, health professionals, and researchers in planning, promoting, and implementing a prenatal exercise program.

Pushing for change: a qualitative study of the experiences of elite athletes during pregnancy

Objectives

Athletes train and compete at the elite level during their reproductive years, yet sport policies that support pregnant athletes are lacking. The experiences of elite athletes during pregnancy are vastly under-represented, and such voices are needed to support evidence-informed policy. Thus, the purpose of this qualitative study was to describe the experiences of elite female athletes as they navigate pregnancy, and to identify sport policy considerations regarding participation during pregnancy.

Methods

Twenty athletes (mean age 35±5 years) who, within the last 5 years, had trained or competed at the elite level immediately prior to becoming pregnant were included. Data were generated via one-on-one semistructured interviews that were audio-recorded, transcribed verbatim and analysed through a process of content analysis.

Results

The findings of this study are represented by one overarching message: mother versus athlete, and five main themes: (1) pregnancy planning and fertility, (2) pregnancy disclosure and discrimination, (3) training pregnant athletic bodies, (4) safety concerns, and (5) supportive network and equitable funding.

Conclusion

In-depth stories shared by participants highlight the many significant decisions athletes must make as they navigate pregnancy alongside elite sport participation. The shared experiences of pregnant athletes highlight clear challenges that should be considered in the development of sport policy and practices that are inclusive and supportive of female athletes.

The Legacy of Pregnancy: Elite Athletes and Women in Arduous Occupations

ABSTRACT

Best-practice guidance and management of pregnant and postpartum elite athletes and women in arduous occupations is limited by the lack of high-quality evidence available within these populations. We have summarised the adaptations and implications of pregnancy and childbirth; proposed a novel integrative concept to address these changes; and made recommendations to progress research in this area.

Effect of aerobic water exercise during pregnancy on epidural use and pain: A multi-centre, randomised, controlled trial

OBJECTIVE

The physical and psychological benefits of exercise during pregnancy are well established. However, the impact of exercise on pain during labour and the use of epidural analgesia has been less explored. The main aim of this study was to analyse the effectiveness and safety of moderate aerobic water exercise by pregnant women on the subsequent use of epidural analgesia during labour, induction of labour, mode of delivery, and pain perception.

DESIGN

A multi-centre, parallel, randomised, evaluator blinded, controlled trial in a primary care setting.

SETTING

Primary care centres in a health district of a tertiary obstetric metropolitan hospital in Mallorca, Spain.

PARTICIPANTS

Pregnant women (14 to 20 weeks' gestation) who had low risk of complications.

METHODS

Three hundred and twenty pregnant women were randomly assigned to two groups: women who practiced moderate aquatic aerobic exercise with usual antenatal care, and those who received usual prenatal care alone. The gynaecologist, anaesthesiologist and midwife who assisted the women during labour were blinded to group allocations. Principal outcome: use of epidural analgesia during labour. Other outcomes: use of epidural analgesia before 6 cm cervical dilation, labour pain, type of delivery, time of active labour, episiotomy or perineal tear, and induction of labour.

RESULTS

The exercise program did not affect the use of epidural analgesia (OR = 0.79, 95% CI = 0.44 to 1.40), vaginal delivery (OR = 1.35, 95% CI = 0.73 to 2.41), or caesarean section (OR = 0.94, 95% CI = 0.47 to 1.89). However, women in the exercise group reported less pain during labour (mean difference: -0.6, 95% CI = -1.11 to -0.09). The two groups (moderate aquatic aerobic exercise versus usual antenatal care) showed no significant differences in maternal or newborn adverse events.

CONCLUSION

Aquatic aerobic exercise during pregnancy had no effect on the use of epidural analgesia during labour, whereas pain perception was lower after aquatic exercise compared to usual care in pregnancy. The intervention was safe for pregnant women and their newborns.

Substrate metabolism during exercise: sexual dimorphism and women's specificities

The aim of this review is to discuss sexual dimorphism of energy metabolism, and to describe the impact of women's hormonal status on substrate oxidation during exercise. Many evidences indicate that sex steroids play a pivotal role in the sex-related differences of body composition and energy substrate storage. Compared with men, women rely more on fat and less on carbohydrates at the same relative exercise intensity. Scientific data suggest that 17-β oestradiol is a key hormone for the regulation of body composition and substrate metabolism. However, in women, measurements with stable isotopic tracers did not highlight any difference in whole-body substrate oxidation rates between the follicular and luteal phases of the menstrual cycle during endurance exercise. The remaining discrepancies about the effect of menstrual cycle-related hormone fluctuations on substrate oxidation could be partly explained by the exercise intensity, which is an important regulator of substrate oxidation. Due to their specific nature and concentration, the synthetic ovarian hormones contained in oral contraceptives also influence substrate metabolism during endurance exercise. However, more studies are needed to confirm that oral contraceptives increase lipolytic activity during endurance exercise without any substantial (or detectable) effect on substrate utilization. Pregnancy and menopause also modify body composition and substrate utilization during exercise through specific hormonal fluctuations.This review highlights that the hormonal status is likely to affect substrate oxidation during exercise in women emphasizing the need to take it into consideration to optimize their health and performance.

Maternal physiological changes at rest induced by exercise during pregnancy: A randomized controlled trial

OBJECTIVE

to analyse maternal physiological changes in several areas (cardiovascular, metabolic, renal and hepatic) related to the regular practice of a supervised exercise program.

METHODS

This is an unplanned secondary analysis from a randomized controlled trial carried out in a single maternity unit in Madrid, Spain (NCT 02,756,143). From November 2014 to June 2015, 92 women were randomly assigned to perform a mild-moderate supervised exercise program during pregnancy (Intervention group, IG) or to continue with their routine pregnancy care (control group, CG). For the purpose of this study we collected clinical and analytical data (heart blood pressure, weight, blood glucose, AST, ALT, blood Creatinine and blood Uric acid) available from all obstetric visits and examined the differences between groups.

RESULTS

We did not find any differences in: pregnancy weight (IG: 11.4 ± 4.4 Kg vs. CG: 10.1 ± 5.3 Kg; p = 0.173); fasting glucose at 10⁺⁰-12⁺⁶ weeks (IG: 78.48±8.34 vs. CG: 76±13.26, p = 0.305) or at 34⁺⁰-36⁺⁴ weeks (IG: 73.25±10.27 vs CG: 73.45± 8.29,p = 0.920), and 50 gs glucose tolerance at 24⁺⁴-26⁺⁶weeks (IG: 116.23±35.07 vs CG: 116.36±25.98, p = 0.984); Aspartate-amino-transferase at 10⁺⁰-12⁺⁶ weeks (IG: 15.38±4.17 vs CG: 17.33±7.05, p = 0.124) and at 34⁺⁰-36⁺⁴ weeks (IG: 21.65±5.25 vs CG: 19.53±8.32, p = 0.165) or Alanine-amino- transferase at 10⁺⁰-12⁺⁶ weeks (IG: 27.50±10.63 vs CG: 28.27±11.77, p = 0.746) or at 34⁺⁰-36⁺⁴ weeks (IG: 22.93±9.23 vs CG: 20.84±13.49, p = 0.407); blood Creatinine concentrations at 34⁺⁰-36⁺⁴ weeks (IG: 0.595±0.401 vs CG: 0.575±0.100, p = 0.757) and blood uric acid concentrations at 34⁺⁰-36⁺⁴ weeks (IG: 3.526 ± 0.787 vs CG: 3.262±0.672, p = 0.218). Heart blood pressure was similar between groups except at 27⁺⁰-28⁺⁶ weeks, where systolic blood pressure was significantly lower in the CG in comparison to the IG (116.31±10.8 mmHg vs. 120.22 ± 10.3 mmHg, p = 0.010).

CONCLUSION

Regular supervised exercise during pregnancy does not alter normal maternal physiology.

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

Importance

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

Objective

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

Evidence Acquisition

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

Results

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

Conclusions and Relevance

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

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

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

Elite athletes get pregnant, have healthy babies and return to sport early postpartum

Objectives

To enhance knowledge on pregnancy and return to sport in the postpartum period in elite female athletes.

Methods

34 Norwegian elite athletes (33.1 years) and 34 active controls (31.5 years) were asked about training and competitive history, pregnancy-related issues, injuries, body dissatisfaction (BD), drive for thinness (DT), eating disorders (ED) and practical experiences, through a questionnaire and interview. Independent samples T-tests or χ² tests for between-group differences and paired-samples T-tests and repeated measures analysis of variance for within group differences were used.

Results

No group differences in fertility problems, miscarriage, preterm birth or low birth weight were found. Both groups decreased training volume all trimesters and the first two postpartum periods compared with prepregnancy, and more athletes returned to sport/exercise at week 0–6 postpartum. We found no group differences in complications during pregnancy and delivery, but athletes reported fewer common complaints. Four athletes experienced stress fracture postpartum. Athletes had higher BD and DT postpartum, while controls reduced DT score. Number of athletes with clinical ED was reduced postpartum, while constant in controls. Athletes were not satisfied with advice related to strength training and nutrition during pregnancy.

Conclusion

Elite athletes and active controls get pregnant easily, deliver healthy babies and decrease training during pregnancy and the first postpartum periods compared with prepregnancy. Most athletes and every third control returned to sport or exercise at week 0–6 postpartum. Athletes report stress fractures and increased BD and DT, but decreased ED postpartum. However, since relatively few athletes were included these findings need further investigation.

The effects of vigorous intensity exercise in the third trimester of pregnancy: a systematic review and meta-analysis

Background

Fetal growth is dependent upon utero-placental vascular supply of oxygen and nutrients from the mother and has been proposed to be compromised by vigorous intensity exercise in the third trimester. The aim of this systematic review was to investigate the effects of vigorous intensity exercise performed throughout pregnancy, on infant and maternal outcomes.

Methods

Electronic searching of the PubMed, Medline, EMBASE, Cochrane Library, Web of Science and CINAHL databases was used to conduct the search up to November 2018. Study designs included in the systematic review were randomised control trials, quasi-experimental studies, cohort studies and case-control studies. The studies were required to include an intervention or report of pregnant women performing vigorous exercise during gestation, with a comparator group of either lower intensity exercise or standard care.

Results

Ten cohort studies (n = 32,080) and five randomized control trials (n = 623) were included in the systematic review (n = 15), with 13 studies included in the meta-analysis. No significant difference existed in birthweight for infants of mothers who engaged in vigorous physical activity and those who lacked this exposure (mean difference = 8.06 g, n = 8006). Moreover, no significant increase existed in risk of small for gestational age (risk ratio = 0.15, n = 4504), risk of low birth weight (< 2500 g) (risk ratio = 0.44, n = 2454) or maternal weight gain (mean difference = − 0.46 kg, n = 1834). Women who engaged in vigorous physical activity had a small but significant increase in length of gestational age before delivery (mean difference = 0.21 weeks, n = 4281) and a small but significantly reduced risk of prematurity (risk ratio = − 0.20, n = 3025).

Conclusions

Findings from this meta-analysis indicate that vigorous intensity exercise completed into the third trimester appears to be safe for most healthy pregnancies. Further research is needed on the effects of vigorous intensity exercise in the first and second trimester, and of exercise intensity exceeding 90% of maximum heart rate.

Trial registration

PROSPERO trial registration CRD42018102109.

Electronic supplementary material

The online version of this article (10.1186/s12884-019-2441-1) contains supplementary material, which is available to authorized users.

Impact of exercise during pregnancy on gestational weight gain and birth weight: an overview

OBJECTIVE

This article presents the state of knowledge related to the impact of exercise on gestational weight gain and birth weight.

TRANSCENDENCE OF BABY WEIGHT

Birth weight is an important indicator of intrauterine environment and maternal and newborn health. There are several factors that can affect birth weight including mother's pre-pregnancy Body Mass Index (BMI), gestational weight gain, Gestational Diabetes Mellitus (GDM), chronic diabetes and gestational age at birth.

IMPACT OF EXERCISE DURING PREGNANCY

Physical exercise has the potential to prevent excessive gestational weight gain, GDM and the potential complications associated with obesity during pregnancy. Therefore, women who regularly exercise during pregnancy are more likely to have an appropriate gestational weight gain and in turn, an appropriate birth weight infant, preventing being LGA without increasing risk of SGA, and this reduces risk factors for later life chronic disease development in the child including cardiovascular disease, obesity and diabetes.

RECOMMENDATIONS

It would be advisable to promote compliance with physical activity and exercise recommendations during pregnancy by using the specific resources to prescribe exercise to pregnant women without obstetric contraindications.

The Influence of Objectively Measured Physical Activity During Pregnancy on Maternal and Birth Outcomes in Urban Black South African Women

Objectives Research indicates the beneficial effects of physical activity during pregnancy on maternal health, although controversy still exists regarding its influence on birth outcomes. Little research has been done to objectively measure physical activity during pregnancy in black African women from low-to-middle income countries. The purpose of this study was to examine the association between physical activity and maternal and birth outcomes in this unique population. Methods This observational, longitudinal study assessed total physical activity using a hip-mounted triaxial accelerometer at 14–18 weeks (second trimester, n = 120) and 29–33 weeks (third trimester, n = 90) gestation. Physical activity is expressed as gravity-based acceleration units (mg). Maternal outcomes included both weight and weight gain at 29–33 weeks gestation. Birth outcomes included gestational age, birth weight, ponderal index and Apgar score, measured within 48 h of delivery. Results There was a significant decline in physical activity from the second to the third trimester (12.8 ± 4.1 mg vs. 9.7 ± 3.6 mg, p ≤ 0.01). Physical activity at 29–33 weeks as well as a change in PA was inversely associated with weight change at 29–33 weeks (β = − 0.24; 95% CI − 0.49; − 0.00; p = 0.05 and β = − 0.36; 95% CI − 0.62; − 0.10; p = 0.01, respectively). No significant associations were found between physical activity and birth outcomes. Conclusions for Practice Physical activity during pregnancy may be an effective method to control gestational weight gain, whilst presenting no adverse risk for fetal development, in women from a low-income urban setting.

Diet and Lifestyle Before and During Pregnancy - Practical Recommendations of the Germany-wide Healthy Start - Young Family Network

Diet and exercise before and during pregnancy affect the course of the pregnancy, the child's development and the short- and long-term health of mother and child. The Healthy Start - Young Family Network has updated the recommendations on nutrition in pregnancy that first appeared in 2012 and supplemented them with recommendations on a preconception lifestyle. The recommendations address body weight before conception, weight gain in pregnancy, energy and nutritional requirements and diet (including a vegetarian/vegan diet), the supplements folic acid/folate, iodine, iron and docosahexaenoic acid (DHA), protection against food-borne illnesses, physical activity before and during pregnancy, alcohol, smoking, caffeinated drinks, oral and dental hygiene and the use of medicinal products. Preparation for breast-feeding is recommended already during pregnancy. Vaccination recommendations for women planning a pregnancy are also included. These practical recommendations of the Germany-wide Healthy Start - Young Family Network are intended to assist all professional groups that counsel women and couples wishing to have children and during pregnancy with uniform, scientifically-based and practical information.

2019 Canadian guideline for physical activity throughout pregnancy

The objective is to provide guidance for pregnant women and obstetric care and exercise professionals on prenatal physical activity. The outcomes evaluated were maternal, fetal or neonatal morbidity, or fetal mortality during and following pregnancy. Literature was retrieved through searches of MEDLINE, EMBASE, PsycINFO, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Scopus and Web of Science Core Collection, CINAHL Plus with Full Text, Child Development & Adolescent Studies, Education Resources Information Center, SPORTDiscus, ClinicalTrials.gov and the Trip Database from inception up to 6 January 2017. Primary studies of any design were eligible, except case studies. Results were limited to English-language, Spanish-language or French-language materials. Articles related to maternal physical activity during pregnancy reporting on maternal, fetal or neonatal morbidity, or fetal mortality were eligible for inclusion. The quality of evidence was rated using the Grading of Recommendations Assessment, Development and Evaluation methodology. The Guidelines Consensus Panel solicited feedback from end users (obstetric care providers, exercise professionals, researchers, policy organisations, and pregnant and postpartum women). The development of these guidelines followed the Appraisal of Guidelines for Research and Evaluation II instrument. The benefits of prenatal physical activity are moderate and no harms were identified; therefore, the difference between desirable and undesirable consequences (net benefit) is expected to be moderate. The majority of stakeholders and end users indicated that following these recommendations would be feasible, acceptable and equitable. Following these recommendations is likely to require minimal resources from both individual and health systems perspectives.

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

OBJECTIF

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

VALEURS

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

RECOMMANDATIONS

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

CONTRE-INDICATIONS

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

CONTRE-INDICATIONS ABSOLUES

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

Do female elite athletes experience more complicated childbirth than non-athletes? A case-control study

OBJECTIVE

Previous studies have suggested that female athletes might be at higher risk of experiencing complications such as caesarean sections and perineal tears during labour than non-athletes. Our aim was to study delivery outcomes, including emergency caesarean section rates, length of the first and second stages of labour and severe perineal tears, in first-time pregnant elite athletes compared with non-athletes.

METHODS

This is a retrospective case-control study comparing birth outcomes of primiparous female elite athletes engaging in high-impact and low-impact sports compared with non-athletic controls. The athletes had prior to birth competed at a national team level or equivalent. Participant characteristics and frequency of training for at least 3 years before a first pregnancy were collected via a self-administered questionnaire. Information on delivery outcome was retrieved from the Icelandic Medical Birth Registry.

RESULTS

In total, 248 participated, 118 controls, 41 low-impact and 89 high-impact elite athletes. No significant differences were found between the groups with regard to incidence of emergency caesarean section or length of the first and second stages of labour. The incidence of third-degree to fourth-degree perineal tears was significantly higher (23.7%) among low-impact athletes than in the high-impact group (5.1%, p=0.01), but no significant differences were seen when the athletes were compared with the controls (12%; p=0.09 for low-impact and p=0.12 for high-impact athletes).

CONCLUSION

Participation in competitive sports at the elite level was not related to adverse delivery outcome, including length of labour, the need for caesarean section during delivery and severe perineal tears.

Association between pregravid physical activity and family history of stroke and risk of stillbirth: population-based cohort study

OBJECTIVES

To evaluate whether family history of disease and pregravid lifestyle and cardiovascular risk factors are associated with subsequent stillbirth delivery.

DESIGN

Prepregnancy cohort study.

SETTING

Cohort Norway regional health surveys (1994-2003) linked to Medical Birth Registry of Norway for deliveries through 2012.

PARTICIPANTS

13 497 singleton births (> 22 weeks gestation) in 8478 women.

MAIN OUTCOME MEASURE

Risk of stillbirth evaluated by Poisson regression.

RESULTS

Mean (SD) length of follow-up was 5.5 (3.5) years. In analyses adjusting for baseline age and length of follow-up, ≥3 hours of baseline past-year vigorous physical activity per week (resulting in shortness of breath/sweating) was associated with increased risk of stillbirth compared with <1 hour/week of vigorous activity (incidence rate ratio, IRR 2.46; 95% CI 1.23 to 4.90). In contrast, baseline past-year light physical activity of ≥3 hours per week associated with reduced risk of stillbirth compared with <3 hours of light physical activity per week (IRR 0.53; 95% CI 0.30 to 0.93). A family history of stroke associated with increased risk of stillbirth delivery (IRR 2.53; 95% CI 1.06 to 6.01). Because overweight/obese women may experience shortness of breath and sweating with less physical exertion than normal weight women, a sensitivity analysis was conducted limited to women with a normal BMI (> 18.5 and <25 kg/m²). Vigorous activity of ≥3 hours per week (IRR of 4.50; 95% CI 1.72 to 11.79) and a family history of stroke (IRR of 3.81; 95% CI 1.31 to 11.07) were more strongly related to stillbirth risk among women with a normal BMI than that observed for all women combined. Established risk factors also associated with stillbirth risk.

CONCLUSIONS

The study identified physical activity and family history of stroke as potential new risk factors for stillbirth delivery.