Physical activity and pregnancy outcomes: an expert review

Dose-Response Effects on LBP, Sleep, and Depression of Online Pre-Partum and Post-Partum Pilates-Based Programs

Purpose: Pilates-based programs can help pregnant women deal with the physical and psychological burden derived by major changes in their body. This study was designed to primarily test, in pregnant women, the dose-response and health effects of both pre-partum and post-partum, online Pilates-based program on weight control, low back pain (LBP) severity, sleep disturbances, mood and depression levels. Methods: A total of 136 pregnant women were screened for eligibility (low-risk pregnancy; aged 18-45 years; single pregnancy; 20-28-week gestational age, normal BMI). Participants completed an online Pilates-based program during pregnancy and after delivery, through an online platform guided by a Pilates, Yoga and Lagree certified instructor. Main outcomes (weight control, LBP disability, sleep quality, mood, and mental health) were assessed at baseline and at the completion of pre- and post-partum programs. Results: Regarding pre-partum, significant gains in weight were observed only in low- and intermediate-amount exercisers. Only high-amount exercisers did not display significant increase in LBP-related disability (+42.7%; p = .21) unlike low (+12.2%; p < .0001) and intermediate exercisers (+9.6%; p < .0001). Sleep disturbances increased significantly in low- (+24.3%; p = .005) but not in intermediate- (+4.6%; p = .50) and high-amount exercisers (-0.1%; p = .91). Regardless of the amount of exercise, depression scores improved in all groups. Following post-partum intervention (n = 40), only intermediate-amount exercisers showed significant reductions in sleep disturbances (-24.1%; p = .003) and depression (15.9%; p = .04). Conclusions: Approximately 270 min/week of an online Pilates-based program were needed to prevent LBP worsening, and sleep deterioration in pregnant women. A different pattern was outlined for those women resuming the Pilates-based intervention at post-partum, with 150 min/week emerging as the "dose" of exercise capable of inducing the largest improvements in LBP, sleep, and mood disturbances.

Physical activity among pregnant inpatients and outpatients and associations with anxiety

OBJECTIVE

Physical activity is linked to lower anxiety, but little is known about the association during pregnancy. This is especially important for antepartum inpatients, who are known to have increased anxiety yet may not be able to achieve target levels of physical activity during hospitalization. We compared physical activity metrics between pregnant inpatients and outpatients and explored correlations with anxiety.

MATERIALS AND METHODS

This was a prospective cohort between 2021 and 2022 of pregnant people aged 18-55 years carrying singleton gestations ≥ 16 weeks. Three exposure groups were matched for gestational age: 1) outpatients from general obstetric clinics; 2) outpatients from high-risk Maternal-Fetal Medicine obstetric clinics; and 3) antepartum inpatients. Participants wore Actigraph GT9X Link accelerometer watches for up to 7 days to measure physical activity. The primary outcome was mean daily step count. Secondary outcomes were metabolic equivalent tasks (METs), hourly kilocalories (kcals), moderate to vigorous physical activity (MVPA) bursts, and anxiety (State-Trait Anxiety Inventory [STAI]). Step counts were compared using multivariable generalized estimating equations adjusting for maternal age, body-mass index, and insurance type as a socioeconomic construct, accounting for within-group clustering by gestational age. Spearman correlations were used to correlate anxiety scores with step counts.

RESULTS

58 participants were analyzed. Compared to outpatients, inpatients had significantly lower mean daily steps (primary outcome, adjusted beta -2185, 95 % confidence interval [CI] -3146, -1224, p < 0.01), METs (adjusted beta -0.18, 95 % CI -0.23, -0.13, p < 0.01), MVPAs (adjusted beta -38.2, 95 % CI -52.3, -24.1, p < 0.01), and kcals (adjusted beta -222.9, 95 % CI -438.0, -7.8, p = 0.04). Over the course of the week, steps progressively decreased for inpatients (p-interaction 0.01) but not for either of the outpatient groups. Among the entire cohort, lower step counts correlated with higher anxiety scores (r = 0.30, p = 0.02).

CONCLUSION

We present antenatal population norms and variance for step counts, metabolic equivalent tasks, moderate to vigorous physical activity bursts, and kcals, as well as correlations with anxiety. Antepartum inpatients had significantly lower physical activity than outpatients, and lower step counts correlated with higher anxiety levels. These results highlight the need for physical activity interventions, particularly for hospitalized pregnant people.

Preeclampsia epidemiology(ies) and pathophysiology(ies)

Preeclampsia/eclampsia was first described 2000 years ago. Concepts guiding diagnosis have changed over time making longitudinal studies challenging. Similarly, concepts of pathophysiology have evolved from eclampsia as a pregnancy seizure disorder to preeclampsia as a hypertensive and renal disorder to our current concept of a preeclampsia as a pregnancy specific, multisystemic inflammatory disorder. Although preeclampsia is pregnancy specific and many pathophysiologic findings begin to resolve with delivery, its impact extends beyond pregnancy. The risk of cardiovascular and neurological disease is increased after pregnancy in women who have had preeclampsia. The disorder is not a disease, but a syndrome and emerging data indicate multiple pathways to the syndrome. It is likely that our failure to have a major impact on prediction and prevention despite a large increase in understanding is due to the existence of multiple subtypes of preeclampsia. This concept should guide future research.

Relationships between physical behaviour phenotypes of mothers in pregnancy and their offspring with child body composition

AIM

The aim of this study was to identify physical behaviour phenotypes in mothers in the first trimester and in their offspring at 24 months of age. The secondary aim was to examine relationships between mother and child behaviours with child body composition at age 24 months.

METHODS

Longitudinal secondary analysis of the Glowing cohort collected between 1 February 2011 and 22 August 2017 in Little Rock, Arkansas. Behaviours were measured using ankle-worn accelerometers in mothers during the first trimester and offspring at 24 months of age, including total activity, sleep, sedentary time and a novel variable of daily variation, patternicity. Child body fat was measured using quantitative nuclear magnetic resonance.

RESULTS

Three phenotypes were identified for mothers and children (n = 159 complete dyads). There were no relationships between mother and child phenotypes, but higher maternal patternicity was associated with higher child patternicity (0.2, 95% CI 0.1, 0.3, p = 0.001). There were no associations between mother or child phenotypes with child body composition, however higher child activity was associated with lower body fat (-0.01, 95% CI: -0.02, -0.001, p = 0.031).

CONCLUSION

Limited associations were found between mothers' pregnancy physical behaviours with child behaviours or child body composition at 24 months of age. Factors such as child diet or current parental physical activity may be better predictors of early childhood outcomes.

Perioperative Exercise Testing in Pregnant and Non-Pregnant Women of Reproductive Age: A Systematic Review

BACKGROUND

Women have classically been excluded from the development of normal data and reference ranges, with pregnant women experiencing further neglect. The incidence of Caesarean section in pregnant women, and of general operative management in young women (both pregnant and non-pregnant), necessitates the formal development of healthy baseline data in these cohorts to optimise their perioperative management. This systematic review assesses the representation of young women in existing reference ranges for several functional exercise tests in common use to facilitate functional assessment in this cohort.

METHODS

Existing reference range data for the exercise tests the Six Minute Walk Test (6MWT), the Incremental Shuttle Walk Test (ISWT) and Cardiopulmonary Exercise Testing (CPET) in young women of reproductive age were assessed using the MEDLINE (Ovid) database, last searched December 2023. Results were comparatively tabulated but not statistically analysed given underlying variances in data.

RESULTS

The role of exercise testing in the perioperative period as an assessment tool, as well as its safety during pregnancy, was evaluated using 65 studies which met inclusion criteria.

CONCLUSION

There is a significant lack of baseline data regarding these tests in this population, especially amongst the pregnant cohort, which limits the application of exercise testing clinically.

Ambulation for latency during expectant management of preterm prelabor rupture of membranes: a randomized controlled trial (AMBLE)

BACKGROUND

Individuals hospitalized with preterm prelabor rupture of membranes are often advised to limit their activity or adhere to bed rest. Some evidence suggests that greater activity is associated with longer latency and improved outcomes, but no high-quality evidence from a randomized controlled trial exists.

OBJECTIVE

This study aimed to evaluate whether encouragement to ambulate at least 2000 steps daily affects latency among individuals with preterm prelabor rupture of membranes compared with usual care.

STUDY DESIGN

This was a multisite unblinded, 2-arm randomized trial of individuals at 23 0/7 to 35 0/7 weeks of gestation undergoing inpatient expectant management of preterm prelabor rupture of membranes with planned delivery at least 7 days away. Each participant wore a Fitbit Inspire that tracked steps. The intervention arm was encouraged (verbal and Fitbit-based reminders) to reach a goal of 2000 steps per day. The usual-care arm was allowed ad libitum activity with no step goal or reminders. The primary outcome was latency (days) from randomization to delivery. Secondary analyses included composite neonatal and maternal clinical outcomes and maternal mental health survey results. Statistical analyses were conducted with an intent-to-treat approach under a Bayesian framework using neutral priors (a priori assumed 50:50 likelihood of longer latency in either arm). A total of 100 participants were required to have 80% power to demonstrate a 4-day difference in latency with 75% certainty (Bayesian probability).

RESULTS

Among 163 eligible individuals, 100 (61%) were randomized, and after loss to follow-up, 95 were analyzed. Gestational age at randomization was 29 3/7 weeks (interquartile range, 26 2/7 to 31 5/7) in the intervention arm and 27 4/7 weeks (interquartile range, 25 4/7 to 29 6/7) in the usual-care arm. Median step counts were 1690 per day in the intervention arm (interquartile range, 1031-2641) and 1338 per day in the usual-care arm (interquartile range, 784-1913). Median days of latency were 9 days in the intervention arm (interquartile range, 4-17) and 6 days in the usual-care arm (interquartile range, 2-14). The primary analysis indicated a 65% posterior probability that the intervention increased latency relative to usual care (posterior relative risk, 1.09; 95% credible interval, 0.70-1.71). The relative risk was 0.55 (95% credible interval, 0.32-0.82) for the composite neonatal adverse outcome, with 99% posterior probability of intervention benefit, and was 0.94 (95% credible interval, 0.72-1.20) for the composite maternal adverse outcome, with 70% posterior probability of intervention benefit. There was a 94% posterior probability of the intervention arm having a greater decrease in maternal stress score from baseline to before delivery compared with the usual-care arm (mean arm difference, 3.24 points [95% credible interval, -7.23 to 0.79]). Adjustment for gestational age at randomization had minimal impact on secondary outcome results.

CONCLUSION

Individuals with preterm prelabor rupture of membranes randomized to encouragement to ambulate had a longer latency to delivery and improved neonatal and mental health outcomes, with similar maternal clinical outcomes compared with usual care.

Impact of adverse pregnancy outcomes on brain vascular health and cognition

A State of the Art lecture titled "Impact of Adverse Pregnancy Outcomes on Brain Vascular Health and Cognition" was presented at the International Society on Thrombosis and Haemostasis Congress in 2023. Adverse pregnancy outcomes, encompassing conditions such as gestational hypertension, eclampsia, preeclampsia, preterm birth, fetal growth restriction, stillbirth, and gestational diabetes, may form part of an underrecognized pathway from early adulthood reproductive health factors to later-life vascular cognitive impairment and dementia in women. Adverse pregnancy outcomes are caused by dysregulated vascular and metabolic adaptations during pregnancy, and these pathophysiological changes may persist after delivery. Adverse pregnancy outcomes may contribute to the increased risk of cognitive impairment and dementia directly through vascular and metabolic dysregulation and subsequent development of cardiovascular diseases, or other biological processes may be at play, such as shared maternal risk factors. Extensive epidemiologic evidence has shown that many cognitive impairment and dementia cases may be prevented or delayed by strategies targeting midlife cardiovascular health. Despite the recognized importance of adverse pregnancy outcomes for cardiovascular health, the literature on associated long-term health outcomes is limited. In this State of the Art review article, we summarize the current epidemiologic evidence on the relationship between adverse pregnancy outcomes and cognitive impairment and dementia and provide an overview of the potential pathophysiological mechanisms. Finally, we summarize relevant new data on this topic presented during the 2023 International Society on Thrombosis and Haemostasis Congress.

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.

The PREDG study: A randomised controlled trial testing whether an educational intervention can prevent gestational weight gain in women with obesity

OBJECTIVE

The PREDG trial was designed to study the influence of an educative program on gestational weight gain in women with pregestational obesity.

METHODS

Randomized controlled clinical trial (https://www.isrctn.com/ISRCTN61793947) in 169 women with pregestational obesity (BMI ≥30 kg/m2). Women were randomized to participate in a group education program in nutrition and physical activity or conventional follow-up in a specialized Unit of Obesity and Pregnancy. The nutritional intervention was adjusted to prepregnancy BMI and to the physical activity intensity. Quality was based on the Mediterranean diet. Macronutrients were distributed as follows: 50% carbohydrates, 20% protein and 30% fat. Adequate gestational weight gain was defined between 5 and 9 kg (IOM 2009). Mean gestational weight gain was compared between groups by using the T Student test and frequencies of adequate gestational weight gain were compared by using ꓫ2.

RESULTS

Gestational weight gain was lower in the intervention group: 8 (4-11) vs 9.2 (6-13) kg, p 0.026. Gestational weight gain was below 9 kg in 24 of 39 (61.5%) women of the intervention vs 10 of 41 (24.4%) of the control group (p 0.001). Regarding obstetric complications, there were 15 (8.3%) cases of gestational diabetes with no differences between the groups. There were 14 of 85 (18.2%) cases of gestational hypertension or preeclampsia in the intervention group compared with 26 of 84 (32.5%) in the control group (p 0.040). With reference to neonatal weight, there were 7 of 82 (8.5%) large for gestational age neonates in the intervention group compared with 15 of 79 (19.2%) in the control group (p 0.050).

CONCLUSIONS

A group-based educative and structured intervention results in an adequate weight gain and lower rates of gestational hypertension, preeclampsia and large for gestational age neonates in pregnant women with obesity.

Recent Advances in the Prevention and Screening of Preeclampsia

Throughout the history of medicine, preeclampsia has remained an enigmatic field of obstetrics. In 2023, despite its prevalence and impact, preeclampsia's exact cause and effective treatment remain elusive; the current options are limited to delivery. The purpose of this review is to summarize the knowledge of the possible novel prophylactic therapies and screening methods for preeclampsia, thereby providing valuable insights for healthcare professionals and researchers. Aspirin and LMWH have already been widely used; meanwhile, calcium, vitamin D, and pravastatin show promise, and endothelin receptor antagonists are being explored. Stress reduction, dietary changes, and lifestyle modifications are also being investigated. Another interesting and fast-growing area is AI- and software-based screening methods. It is also key to find novel biomarkers, which, in some cases, are not only able to predict the development of the disease, but some of them hold promise to be a potential therapeutic target. We conclude that, while a definitive cure for preeclampsia may not be eligible in the near future, it is likely that the assessment and enhancement of preventive methods will lead to the prevention of many cases. However, it is also important to highlight that more additional research is needed in the future to clarify the exact pathophysiology of preeclampsia and to thus identify potential therapeutic targets for more improved treatment methods.

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.

Activity restriction for women with arrested preterm labor: a randomized controlled trial

BACKGROUND

In the past, some pregnant women have been recommended to be in activity restriction because of the presumed increased risk of preterm birth due to the increased release of catecholamines, which might stimulate myometrial activity, during exercise and aerobic activity.

OBJECTIVE

This study aimed to test the hypothesis that in women with singleton pregnancy and arrested preterm labor, activity restriction would reduce the rate of preterm birth at <37 weeks of gestation.

STUDY DESIGN

This was a parallel-group nonblinded randomized trial conducted at a single center in Italy. Eligible patients were those with a diagnosis of arrested preterm labor, defined as not delivering after 48 hours of hospitalization for threatened preterm labor, with transvaginal ultrasound cervical length ≤25 mm, no other symptoms of possible uterine contractions, and cervical dilatation <3 cm at pelvic examination. Inclusion criteria were singleton pregnancies between 24 0/7 and 33 6/7 weeks of gestation. Participants were randomized in a 1:1 ratio to either activity restriction at the time of discharge or no activity restriction. Women in the intervention group were recommended activity restriction, defined as the following: pelvic rest, prohibition of sexual activity, and reduction of work and/or nonwork activity. The primary endpoint was preterm birth at <37 weeks of gestation.

RESULTS

A total of 120 participants were included in the trial; 60 patients were enrolled in the activity restriction group and 60 in the control group. Preterm birth at <37 weeks of gestation occurred in 15 of 60 women (25.0%) in the activity restriction group and 23 of 60 women (38.3%) in the control group (relative risk, 0.65; 95% confidence interval, 0.38-1.12). There was no significant between-group difference in the incidence of preterm birth at <32 weeks and in neonatal outcomes, but the trial was not powered for these outcomes.

CONCLUSION

In singleton gestations with arrested preterm labor, activity restriction, including pelvic rest, prohibition of sexual activity, and reduction of work and/or nonwork activity, does not result in a lower rate of preterm birth at <37 weeks. Given the evidence on the lack of benefits, use of activity restriction in this population should be discouraged.

Puerperium experience and lifestyle in women with gestational diabetes mellitus and overweight/obesity in China: A qualitative study

Introduction

Women with overweight or obesity and gestational diabetes mellitus (GDM) are at a high risk of developing type 2 diabetes mellitus (T2DM) and other metabolic diseases. Healthy postpartum lifestyles in women with GDM are important for effectively preventing early T2DM occurrence; however, few studies and guidelines focus in China on this issue.

Aims

This qualitative study aimed to understand the puerperium experience and lifestyle of women with overweight/obesity and GDM.

Methods

A face-to-face, in-depth, and semi-structured interview was conducted using a hermeneutical phenomenology method to collect data that were analyzed through thematic analysis.

Results

Out of 61 recruited women with overweight/obesity and history of GDM, 14 women underwent an interview and provided detailed descriptions of their lifestyle experiences during puerperium. The interview data were used to generate four themes—puerperium dietary behavior, weight perception and “confinement” behavior, family support, disease knowledge, and perceived risk—and nine sub-themes.

Conclusion

Unhealthy lifestyles, misconceptions about food, the conflict between physical activity and confinement behavior, a lack of social and family support, and low awareness of disease risk are all common among overweight/obese women with a history of GDM. Thus, we emphasized that healthcare providers should provide continuous preventive care from pregnancy to postpartum and promote long-term health in high-risk populations with a history of GDM associated with overweight/obesity.