The association between leisure time physical activity in the year before pregnancy and pre-eclampsia

Why are pregnant women physically inactive? A qualitative study on the beliefs and perceptions about physical activity during pregnancy

This study aimed to describe the beliefs and perceptions of pregnant women and healthcare providers about physical activity during pregnancy. Using a qualitative approach, 30 pregnant women and the 14 healthcare providers caring for them were interviewed in the second trimester of pregnancy. We included women who maintained, decreased, or stopped physical activity since becoming pregnant. They were divided into low (≤ 8 years) and high schooling (> 8 years). Semi-structured, in-depth interviews were conducted and guided by three key questions: (1) When does physical activity during pregnancy start to be considered a wrong behavior?; (2) What are the main barriers (biological or others) to physical activity?; and (3) Do the actions of healthcare providers and people close to pregnant women reinforce barriers? Interviews were audio recorded, transcribed, and analyzed based on recurring themes. All women changed their physical activity behavior (decreased or stopped) when they discovered their pregnancy. Fear of miscarriage, contractions, bleeding, and of causing malformations in the baby were the most reported reasons for decreasing or stopping physical activity. Participants also lacked access to consistent information and healthcare providers' support on the benefits of physical activity. Despite the current international recommendations to regular physical activity during pregnancy, uncertainty regarding its benefits remains. Interventions to promote physical activity during this period should include the training of healthcare providers so they can advise and discard ideas contrary to mother-child health benefits.

Physical activity before pregnancy and the risk of hypertensive disorders of pregnancy

BACKGROUND

It is unclear whether pre-pregnancy physical activity influences the risk of hypertensive disorders of pregnancy and whether any impact is similar for preeclampsia or gestational hypertension.

OBJECTIVE

To evaluate the relation between pre-pregnancy physical activity with hypertensive disorders of pregnancy and its alignment with current recommendations for physical activity for the general population.

METHODS

We studied 28,147 singleton pregnancies from 18,283 women participating in the Nurses' Health Study-II without chronic hypertension, cardiovascular disease, or cancer, between 1989 and 2010. Women self-reported physical activity before pregnancy and pregnancy complications, including preeclampsia and gestational hypertension. Logistic regression models using generalized estimating equations to account for within-woman correlations across pregnancies were used to estimate the relative risk (95%CI) of preeclampsia and gestational hypertension across quartiles of pre-pregnancy physical activity, adjusting for age at pregnancy, parity, smoking, multivitamin use, infertility history, marital status, race, year of pregnancy, and history of preeclampsia.

RESULTS

We identified 842 (3.0%) pregnancies with preeclampsia and 905 (3.2%) pregnancies with gestational hypertension. Physical activity before pregnancy was related to a lower risk of hypertensive disorders of pregnancy (RR=0.75 [95%CI: 0.65, 0.87] for women in the highest quartile compared to the lowest quartile). This relation was driven by a 39% lower risk of gestational hypertension (RR=0.61; 95%CI:0.50,0.76) comparing women in the highest quartile of physical activity (≥ 30.6 MET-h/wk) vs. women in the lowest quartile (<6.0 MET-h/wk). Women whose moderate physical activity levels exceeded those recommended in the Physical Activity Guidelines for Americans (>5 h/wk) had a 50% lower (RR=0.50; 95%CI:0.36,0.69) risk of gestational hypertension than women who did not meet this recommendation (<2.5h/wk). For vigorous physical activity, the risk of gestational hypertension was lower among women who met (1.25-2.5 h/wk; RR=0.77; 95%CI: 0.64, 0.93) or exceeded (>2.5h/wk; RR=0.76; 95%CI: 0.62,0.92) the recommendations than women whose activity levels were below those recommended. Physical activity was not related to the risk of preeclampsia (RR=0.93; 95%CI:0.76,1.14).

CONCLUSIONS

Physical activity before pregnancy may lower the risk of developing gestational hypertension but not preeclampsia.

Increased physical activity is correlated with improved pregnancy outcomes in women with preeclampsia: A retrospective study

OBJECTIVES

Several studies have focused on the benefits of physical activity to prevent and treat preeclampsia, given that preeclampsia and cardiovascular disease share several risk factors. However, none of these studies have been conducted in Africa. Moreover, it has been demonstrated that exercise training has preventive effects on the development of preeclampsia in mouse models. Therefore, we evaluated the association between the practice of physical activity and the development of this pathology in a Tunisian cohort.

STUDY DESIGN

Sixty-one healthy pregnant Tunisian women and 45 women with preeclampsia were recruited and completed the Pregnancy Physical Activity Questionnaire to determine their level and type of physical activity during the entire pregnancy.

MAIN OUTCOME MEASURE

Continuous variables were compared using the Mann-Whitney U test, while categorical variables were compared using the Chi-square test. The correlation between preeclampsia features and energy expenditure were assessed using the Pearson's correlation test.

RESULTS

Energy expenditure analysis revealed that women with preeclampsia engaged in more sedentary activities than controls, while controls practiced more physical activities. Interestingly, we found a positive correlation between the total amount of energy spent and the duration of pregnancy in controls and women with preeclampsia.

CONCLUSIONS

Increasing physical activity is correlated with increasing pregnancy duration which is an index of maternal and fetal health. The practice of physical activities during pregnancy is associated with a healthier pregnancy, while sedentary activities is associated with the development of preeclampsia.

Influence of pre-pregnancy leisure time physical activity on gestational and postpartum weight gain and birth weight - a cohort study

In order to examine the association between pre-pregnancy leisure time physical activities and gestational weight gain, postpartum weight gain and birth weight, we analysed prospectively collected data from 1827 women with singleton term pregnancies. Women were categorised in groups of sedentary women, light exercisers, moderate exercisers and competitive athletes. The results showed that sedentary women on average gained 14.1 kg during pregnancy, whereas light exercisers gained 13.7 kg, moderate exercisers gained 14.3 kg and competitive athletes 16.1 kg. Competitive athletes had an increased risk of having a gestational weight gain above Institute of Medicine (IOM) recommendations with an odds ratio of 2.60 (1.32-5.15) compared to light exercisers. However, birth weight and one year postpartum weight was similar for all four groups. Thus, although competitive athletes gain more weight than recommended during pregnancy, this may not affect birth weight or postpartum weight. Impact statement What is already known on this subjectPrevious studies have found that increased pre-pregnancy physical activity is associated with lower gestational weight gain during the last trimester, but showed no association between the pre-pregnancy level of physical activity and mean birth weight. What the results of this study addWe found that women classified as competitive exercisers had a 2.6-fold increased risk of gaining more weight than recommended compared to light exercisers. Nearly 6 out of 10 women among the competitive exercisers gained more weight than recommended by IOM. Surprisingly, this did not appear to increase birth weight or post-partum weight gain, but other adverse effects cannot be excluded. What the implications are of these findings for clinical practice and/or further researchIn the clinical practice it may be relevant to focus on and advise pre-pregnancy competitive exercisers in order to prevent excessive gestational weight gain.

Leisure time physical activity and the risk of pre-eclampsia: a systematic review

Today, pre-eclampsia (PE) is one of the leading causes of maternal and perinatal morbidity and mortality. It has been proposed that leisure time physical activity (LTPA) is associated with a decreased risk of PE. The objective of this study was to perform a systematic literature review examining the association between LTPA before and/or during pregnancy and the risk of PE. A systematic search of the EMBASE and PUBMED databases from inception to November 17, 2011 was conducted by two independent reviewers. Only studies describing the association between the intensity or amount of LTPA before and/or during pregnancy and the risk of PE were included. A narrative synthesis of the results was undertaken following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A quality assessment was performed using the Newcastle Ottawa Scale. Eleven studies were included. None of the studies found light- or moderate-intensity LTPA to be associated with PE. Three studies reported that vigorous-intensity LTPA before and/or during pregnancy may reduce the risk of PE. One study reported a reduced risk among women who participated in LTPA at least 25 times per month or more than 4 h per week. However, one study found an elevated risk of severe PE with high amounts of LTPA, defined as 4.5 h per week or more. Results are mixed, but high intensity LTPA before and/or during pregnancy or more than 4 h per week of LTPA may reduce the risk of PE. However, an urgent need remains for high-quality studies including different ethnicities to further explore this relationship.

Physical activity and the risk of preeclampsia: a systematic review and meta-analysis

BACKGROUND

Physical activity has been hypothesized to reduce the risk of preeclampsia, but epidemiologic studies have not shown consistent results. Therefore, we conducted a systematic review and dose-response meta-analysis of epidemiologic studies.

METHODS

PubMed, Embase, and Ovid databases were searched for case-control and cohort studies of physical activity and preeclampsia up to 2 November 2012. We estimated summary relative risks (RRs) using a random effects model.

RESULTS

Fifteen studies were included. The summary RR for high versus low prepregnancy physical activity was 0.65 (95% confidence interval [CI] = 0.47-0.89, I = 0%; n = 5). In the dose-response analysis, the summary RR was 0.72 (0.53-0.99; I = 0%; n = 3) per 1 hour per day and 0.78 (0.63-0.96; I = 0%; n = 2) per 20 metabolic equivalent task (MET)-hours per week. The summary RR for high versus low physical activity in early pregnancy was 0.79 (0.70-0.91; I = 0%; n = 11). In the dose-response analysis, the summary RR per 1 hour per day was 0.83 (0.72-0.95; I = 21%; n = 7) and 0.85 (0.68-1.07; I = 69%; n = 3) per 20 MET-hours per week. A nonlinear association was observed for physical activity before pregnancy and risk of preeclampsia (test for nonlinearity, P = 0.03), but not for physical activity in early pregnancy (test for nonlinearity, P = 0.37), with a flattening of the curve at higher levels of activity. Both walking and greater intensity of physical activity were inversely associated with preeclampsia.

CONCLUSIONS

Our analysis suggests a reduced risk of preeclampsia with increasing levels of physical activity before pregnancy and during early pregnancy.

Physical activity and pregnancy: past and present evidence and future recommendations

PURPOSE

In this review, we provide researchers and practitioners with an overview of the physical activity and pregnancy literature to promote prenatal physical activity, improve measurement, further elucidate the role of activity in reducing maternal health complications, and inform future research.

METHOD

We examined past and present physical activity and pregnancy studies and highlight key papers with a focus on maternal health outcomes to best inform physical activity promotion efforts.

RESULTS

We discuss: (a) historical overview of prenatal physical activity relative to the physical activity guidelines, how they have changed over time, and how evidence of the effect of prenatal activity on maternal/fetal health outcomes has affected clinical recommendations; (b) existing tools and challenges associated with measuring prenatal physical activity; (c) empirical evidence on multilevel determinants of prenatal activity to guide future intervention work; (d) empirical evidence of prenatal activity on adverse maternal outcomes (gestational diabetes mellitus, preeclampsia, excessive gestational weight gain) from observational and intervention studies; and (e) summary/recommendations for future research and practice.

CONCLUSIONS

The physical activity and pregnancy literature has evolved over the past 50 years, and there is sufficient empirical evidence to support the promotion of moderate-to-vigorous prenatal physical activity for maternal health benefits. Future studies and interventions should be carefully designed, theoretically driven, and include validated and reliable activity measures. Researchers and practitioners should also consider the multifaceted determinants and outcomes of prenatal physical activity and intervene to promote physical activity before, during, and after pregnancy.

Impact of exercise training on preeclampsia: potential preventive mechanisms

Preeclampsia is characterized by hypertension and de novo proteinuria after 20 weeks of pregnancy. It is the leading cause of perinatal morbidity and mortality in the developed world, and to date, the only means of treating the disease is by inducing delivery. Many studies have shown the benefits of exercise training on normal pregnancy. Conversely, because the impact of exercise on reducing the risk of preeclampsia has long been debated, the American College of Obstetricians and Gynecologists has yet to support the prescription of exercise training to women at risk of developing the disease. There is, however, a significant body of evidence in support of the protective role of exercise training against preeclampsia. A recent animal study demonstrated that many preeclampsia features can be eliminated with prenatal followed by gestational exercise training. Hence, the present article reviews the literature on the impact of exercise training on preeclampsia risk, as well as the mechanisms that may be involved.

Exercise and physical activity in the prevention of pre-eclampsia: systematic review

Exercise and physical activity have been studied and suggested as a way to reduce or minimize the effects of pre-eclampsia. Our aim was to evaluate the association between exercise and/or physical activity and occurrence of pre-eclampsia. We conducted electronic searches without year of publication and language limitations. This was a systematic review designed according to PRISMA. Different databases accessed were as follows: PubMed®; Latin-American and Caribbean Literature in Health Sciences (LILACS); Scientific Electronic Library On-line (SciELO); Physiotherapy Evidence Database (PEDro); and ISI web of Knowledge(SM) . The Medical Subject Headings (MeSH) were as follows: ("exercise" OR "motor activity" OR "physical activity") AND ("pre-eclampsia" OR "eclampsia" OR "hypertension, pregnancy-induced"). Inclusion criteria were studies conducted in adults who were engaged in some physical activity. The selection and methodological evaluation were carried out by two independent reviewers. Risk assessment was made by the odds ratio (OR) and incidence of pre-eclampsia in the population who performed physical activity/exercise. A total of 231 articles were found, 214 of which were excluded based on title and full-text, so that 17 remained. Comparison of six case-control studies showed that physical activity had a protective effect on the development of pre-eclampsia [OR 0.77, 95% confidence interval (CI) 0.64-0.91, p < 0.01]. The 10 prospective cohort studies showed no significant difference (OR 0.99, 95% CI 0.93-1.05, p= 0.81). The only randomized clinical trial showed a protective effect on the development of pre-eclampsia in the stretching group (OR 6.34, 95% CI 0.72-55.37, p= 0.09). This systematic review indicates a trend toward a protective effect of physical activity in the prevention of pre-eclampsia.

Hypertension in pregnancy

Hypertension is a common complication of pregnancy. Preeclampsia, in particular, is associated with substantial risk to both the mother and the fetus. Several risk factors have been recognized to predict risk for preeclampsia. However, at present no biomarkers have sufficient discriminatory ability to be useful in clinical practice, and no effective preventive strategies have yet been identified. Commonly used medications for the treatment of hypertension in pregnancy include methyldopa and labetalol. Blood pressure thresholds for initiating antihypertensive therapy are higher than outside of pregnancy. Women with prior preeclampsia are at increased risk of hypertension, cardiovascular disease, and renal disease.