The association between gestational diabetes mellitus and recreational physical activity

Intervention planning and modification of the BUMP intervention: a digital intervention for the early detection of raised blood pressure in pregnancy

BACKGROUND

Hypertensive disorders in pregnancy, particularly pre-eclampsia, pose a substantial health risk for both maternal and foetal outcomes. The BUMP (Blood Pressure Self-Monitoring in Pregnancy) interventions are being tested in a trial. They aim to facilitate the early detection of raised blood pressure through self-monitoring. This article outlines how the self-monitoring interventions in the BUMP trial were developed and modified using the person-based approach to promote engagement and adherence.

METHODS

Key behavioural challenges associated with blood pressure self-monitoring in pregnancy were identified through synthesising qualitative pilot data and existing evidence, which informed guiding principles for the development process. Social cognitive theory was identified as an appropriate theoretical framework. A testable logic model was developed to illustrate the hypothesised processes of change associated with the intervention. Iterative qualitative feedback from women and staff informed modifications to the participant materials.

RESULTS

The evidence synthesis suggested women face challenges integrating self-monitoring into their lives and that adherence is challenging at certain time points in pregnancy (for example, starting maternity leave). Intervention modification included strategies to address adherence but also focussed on modifying outcome expectancies, by providing messages explaining pre-eclampsia and outlining the potential benefits of self-monitoring.

CONCLUSIONS

With an in-depth understanding of the target population, several methods and approaches to plan and develop interventions specifically relevant to pregnant women were successfully integrated, to address barriers to behaviour change while ensuring they are easy to engage with, persuasive and acceptable.

Physical activity pattern in early pregnancy and gestational diabetes mellitus risk among low-income women: A prospective cross-sectional study

Objective:

Gestational diabetes mellitus is increasing worldwide, mainly in developing countries, and physical activity has not been studied in gestational diabetes mellitus prevention among low-income population. This prospective cross-sectional study assessed the gestational diabetes mellitus risk related to physical activity in early pregnancy among low-income women.

Methods:

A prospective cross-sectional study with 544 low-income pregnant women was conducted at the Instituto de Medicina Integral Prof. Fernando Figueira, Brazil. Gestational diabetes mellitus was diagnosed using the International Association of Diabetes and Pregnancy Study Groups criteria. Physical activity was assessed during early pregnancy using the Pregnancy Physical Activity Questionnaire and categorized as sedentary, light, moderate, or vigorous intensity.

Results:

Gestational diabetes mellitus occurred in 95 of 544 women (17.4%). Body mass index was higher in the gestational diabetes mellitus group. Nearly half of all pregnant women studied were physically inactive, and none of them were classified as vigorous physical active. Sedentary physical activity pattern was associated with a higher odds of gestational diabetes mellitus (odds ratio = 1.8, 95% confidence interval = 1.1–2.9), which did not change after adjusting for several covariates (odds ratio = 1.9, 95% confidence interval = 1.2–3.1).

Conclusion:

Physical inactivity in early pregnancy is associated with a higher risk of gestational diabetes mellitus among low-income women.

Assessment of physical activity status among pregnant women in southwestern China

Objective

To assess the patterns and intensities of physical activity among pregnant women in southwestern China, which help us create a fitness regimen based on the 2002 American College of Obstetricians and Gynecologists (ACOG) guidelines for exercise during pregnancy.

Methods

A cross-sectional study was performed to recruit pregnant women at a prenatal checking visit clinic with the self-administered Chinese version of Pregnancy Physical Activity Questionnaire (PPAQ).

Results

A total of 1179 Chinese pregnant women were enrolled, of whom 92.60% were classified as not meeting the ACOG guidelines. By intensity, 47.36% of the score was attributed to light-intensity activities (1.5 to <3.0 metabolic equivalent [MET]) in the first trimester; the other 2 trimesters were similar. By patterns, about 45.15% of the score was attributed to inactivity. More than 82.35% of enrolled pregnant women regarded slowly walking as the most common type of exercise during pregnancy.

Conclusions

This study represents a group of Chinese women who maintained an inactive lifestyle, including low-intensity activities and unitary type of exercises during their pregnancy. Health-care providers are advised to provide appropriate physical activity guidelines to pregnant women. Development of MET-hours/week recommendations is warranted to promote greater physical activity during pregnancy.

Effect of Physical Activity during Pregnancy on Gestational Diabetes Mellitus

AIMS

The present study evaluates association between physical activity and Gestational Diabetes Mellitus (GDM), for it can be an effective intervention for its management. Though physical activity helps maintain glucose homeostasis, evidences of GDM risk are less extensive. Therefore, this study also identifies its correlation with maternal blood glucose levels.

MATERIALS AND METHODS

A prospective case-control study was carried out among pregnant women attending regular antenatal clinic at two private hospitals. The study comprised of 100 cases and 273 matched controls. Data was collected by personal interviews using a standard questionnaire. Physical activity was assessed using long form of International Physical Activity Questionnaire (IPAQ) reported as Metabolic Equivalent-Minutes per week (MET-Minutes/Week). Statistical Package for Social Sciences (SPSS) was used for analysis.

RESULTS

Results shows high exposure rates for low-to-moderate physical activity among cases, across all domains and sub-activities. The odds of GDM engaged in domestic and gardening activities for <2999 MET-minutes per week are 10 times higher than involved for ≥3000 MET-minutes per week (P < 0.001). The study also shows poor or no correlation between physical activity during pregnancy and maternal blood glucose levels.

CONCLUSION

Despite existence of poor or no relationship with maternal blood glucose levels, prolonged sedentary behavior and decreased physical activities, especially domestic, are potential risk factors for GDM, a major finding of the study.

Risk Factors for Gestational Diabetes Mellitus: A Case-Control Study

Background: The underlying causes of gestational diabetes mellitus (GDM) are important because they are effective for the diagnosis and prevention of this condition. The aim of this study was to identify the risk factors for GDM and the possible etiological agents. Materials and Methods: This case-control study was conducted with 100 women with GDM and 100 healthy pregnant women at a tertiary care hospital, affiliated to Babol University. GDM was identified by impaired oral glucose tolerance test based on the Carpenter and Coustan criteria. Healthy women were randomly selected from the prenatal health care clinic of the same center and were matched to gestational age of 24 to 28 weeks. Descriptive and inferential statistics were used for data analysis via the SPSS software. Results: After adjusting variables, multivariate analysis identified 4 significant risk factors of GDM, including prepregnancy low physical activity (odds ratio [OR] = 2.85, 95% confidence interval [CI]= 0.97-8.34), advanced maternal age (OR = 1.24, 95% CI = 1.13-1.35), body mass index ⩾ 30 kg/m² (OR = 1.10, 95% CI = 1.02-1.20), and family history of diabetes mellitus (OR = 5.62, 95% CI = 2.26-13.96). Conclusion: We observed significant associations between low prepregnancy physical activity and obesity with GDM risk. Thus the finding of this study can help devise strategies for the prevention of GDM.

Reasons, Motivational Factors, and Perceived Personal Barriers to Engagement in Physical Activity During Pregnancy Vary Within the BMI Classes: The Prenatal Prevention Project Germany

BACKGROUND

International data indicate that approximately only 20.0% of pregnant women reach physical activity recommendations (≥150 min/wk). To find ways for increasing physical activity, the reasons for exercising, motivational factors, and barriers need to be determined. The aim of this pilot study was to identify these factors in respect to body mass index classification in German pregnant women.

METHODS

A total of 61 women [age: 32.7 (4.8) y; 13.3 (3.4) wk of gestation] participated in this study. Before pregnancy, 10.0% of women were underweight, 58.3% were normal weight, 18.3% were overweight, and 13.4% were obese. Standardized questionnaires were used to evaluate the abovementioned factors.

RESULTS

"Fun" was one of the main reasons for being active in underweight/normal weight compared with overweight/obese women (53.7% vs 10.5%; P = .002), whereas "burning fat" was more important in overweight/obese women (9.8% vs 36.8%; P = .027). According to motivational factors, differences occurred in "calorie burning" (7.3% underweight/normal weight vs 31.6% overweight/obese; P = .025) and "fat burning" (7.3% underweight/normal weight vs 47.4% overweight/obese; P = .001). Regarding barriers for being active, "tiredness" was more often a barrier in overweight/obese (63.2%) compared with normal weight/underweight women (31.7%; P = .022).

CONCLUSION

Pregnant women should be given tailored advice/motivation according to prepregnancy body mass index. However, larger studies are necessary to evaluate these factors on pregnant women's physical activity level.

Combined diet and exercise interventions for preventing gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with a wide range of adverse health consequences for women and their infants in the short and long term. With an increasing prevalence of GDM worldwide, there is an urgent need to assess strategies for GDM prevention, such as combined diet and exercise interventions. This is an update of a Cochrane review that was first published in 2015.

OBJECTIVES

To assess the effects of diet interventions in combination with exercise interventions for pregnant women for preventing GDM, and associated adverse health consequences for the mother and her infant/child.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (27 November 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and cluster-RCTs, comparing combined diet and exercise interventions with no intervention (i.e. standard care), that reported on GDM diagnosis as an outcome. Quasi-RCTs were excluded. Cross-over trials were not eligible for inclusion. We planned to include RCTs comparing two or more different diet/exercise interventions, however none were identified.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data, assessed the risk of bias of the included trials and assessed quality of evidence for selected maternal and infant/child outcomes using the GRADE approach. We checked data for accuracy.

MAIN RESULTS

In this update, we included 23 RCTs (involving 8918 women and 8709 infants) that compared combined diet and exercise interventions with no intervention (standard care). The studies varied in the diet and exercise programs evaluated and health outcomes reported. None reported receiving funding from a drug manufacturer or agency with interests in the results. Overall risk of bias was judged to be unclear due to the lack of methodological detail reported. Most studies were undertaken in high-income countries.For our primary review outcomes, there was a possible reduced risk of GDM in the diet and exercise intervention group compared with the standard care group (average risk ratio (RR) 0.85, 95% confidence interval (CI) 0.71 to 1.01; 6633 women; 19 RCTs; Tau² = 0.05; I² = 42%; P = 0.07; moderate-quality evidence). There was also a possible reduced risk of caesarean section (RR 0.95, 95% CI 0.88 to 1.02; 6089 women; 14 RCTs; moderate-quality evidence). No clear differences were seen between groups for pre-eclampsia (RR 0.98, 95% CI 0.79 to 1.22; 5366 participants; 8 RCTs; low-quality evidence), pregnancy-induced hypertension and/or hypertension (average RR 0.78, 95% CI 0.47 to 1.27; 3073 participants; 6 RCTs; Tau² = 0.19; I² = 62%; very low-quality evidence), perinatal mortality (RR 0.82, 95% CI 0.42 to 1.63; 3757 participants; 2 RCTs; low-quality evidence) or large-for-gestational age (RR 0.93, 95% CI 0.81 to 1.07; 5353 participants; 11 RCTs; low-quality evidence). No data were reported for infant mortality or morbidity composite.Subgroup analyses (based on trial design, maternal body mass index (BMI) and ethnicity) revealed no clear differential treatment effects. We were unable to assess the impact of maternal age, parity and specific features of the diet and exercise interventions. Findings from sensitivity analyses (based on RCT quality) generally supported those observed in the main analyses. We were not able to perform subgroup analyses based on maternal age, parity or nature of the exercise/dietary interventions due to the paucity of information/data on these characteristics and the inability to meaningfully group intervention characteristics.For most of the secondary review outcomes assessed using GRADE, there were no clear differences between groups, including for perineal trauma (RR 1.27, 95% CI 0.78 to 2.05; 2733 participants; 2 RCTs; moderate-quality evidence), neonatal hypoglycaemia (average RR 1.42, 95% CI 0.67 to 2.98; 3653 participants; 2 RCTs; Tau² = 0.23; I² = 77%; low quality evidence); and childhood adiposity (BMI z score) (MD 0.05, 95% CI -0.29 to 0.40; 794 participants; 2 RCTs; Tau² = 0.04; I² = 59%; low-quality evidence). However, there was evidence of less gestational weight gain in the diet and exercise intervention group compared with the control group (mean difference (MD) -0.89 kg, 95% CI -1.39 to -0.40; 5052 women; 16 RCTs; Tau² = 0.37; I² = 43%;moderate-quality evidence). No data were reported for maternal postnatal depression or type 2 diabetes; childhood/adulthood type 2 diabetes, or neurosensory disability.

AUTHORS' CONCLUSIONS

Moderate-quality evidence suggests reduced risks of GDM and caesarean section with combined diet and exercise interventions during pregnancy as well as reductions in gestational weight gain, compared with standard care. There were no clear differences in hypertensive disorders of pregnancy, perinatal mortality, large-for-gestational age, perineal trauma, neonatal hypoglycaemia, and childhood adiposity (moderate- tovery low-quality evidence).Using GRADE methodology, the evidence was assessed as moderate to very low quality. Downgrading decisions were predominantly due to design limitations (risk of bias), and imprecision (uncertain effect estimates, and at times, small sample sizes and low event rates), however two outcomes (pregnancy-induced hypertension/hypertension and neonatal hypoglycaemia), were also downgraded for unexplained inconsistency (statistical heterogeneity).Due to the variability of the diet and exercise components tested in the included studies, the evidence in this review has limited ability to inform practice. Future studies could describe the interventions used in more detail, if and how these influenced behaviour change and ideally be standardised between studies. Studies could also consider using existing core outcome sets to facilitate more standardised reporting.

Associations of physical activity and sedentary behavior during pregnancy with gestational diabetes mellitus among Asian women in Singapore

BACKGROUND

Few studies have investigated physical activity (PA) and sedentary behavior (SB) in relation to fasting (FG) and 2-h postprandial plasma glucose (2hPG) levels and gestational diabetes mellitus (GDM); we investigated these associations among Asian pregnant women.

METHODS

As part of the Growing Up in Singapore Towards healthy Outcomes cohort study, PA and SB (sitting and television times) were assessed by interviewer-administered questionnaire. During 75 g oral glucose tolerance tests at 26-28 weeks' gestation we measured FG, 2hPG levels and GDM (FG ≥ 7.0 mmol/L and/or 2hPG ≥ 7.8 mmol/L). Associations were analysed by multiple linear and logistic regression.

RESULTS

Among the 1083 women studied, 18.6% had GDM. SB was not associated with FG, 2hPG and GDM. Higher categories of PA were associated with lower 2hPG and a lower likelihood of GDM (p-trend < 0.05), but not with FG levels. Compared to insufficiently active women, highly active women had lower 2hPG levels [β (95% CI): -0.32 (-0.59, -0.05), p = 0.020) and were less likely to have GDM [OR: 0.56 (0.32-0.98), p = 0.040]. Stratified analysis revealed no associations among under/normal-weight women, but significant associations among overweight/obese women; in those with BMI ≥23 kg/m2, sufficiently active and highly active women were less likely to have GDM [OR: 0.52, (0.29-0.93), p = 0.028, and OR: 0.34, (0.15-0.77), p = 0.010, respectively].

CONCLUSION

Higher PA was associated with lower 2hPG levels and a lower prevalence of GDM, particularly in overweight/obese women. Further studies are warranted to confirm these findings, and to examine the effectiveness of PA promotion strategies for the prevention of gestational hyperglycemia.

Physical activity and the risk of gestational diabetes mellitus: a systematic review and dose-response meta-analysis of epidemiological studies

Physical activity has been inconsistently associated with risk of gestational diabetes mellitus in epidemiological studies, and questions remain about the strength and shape of the dose-response relationship between the two. We therefore conducted a systematic review and meta-analysis of cohort studies and randomized trials on physical activity and gestational diabetes mellitus. PubMed, Embase and Ovid databases were searched for cohort studies, and randomized controlled trials of physical activity and risk of gestational diabetes mellitus, up to August 5th 2015. Summary relative risks (RRs) were estimated using a random effects model. Twenty-five studies (26 publications) were included. For total physical activity the summary RR for high versus low activity was 0.62 (95 % CI 0.41-0.94, I2 = 0 %, n = 4) before pregnancy, and 0.66 (95 % CI 0.36-1.21, I2 = 0 %, n = 3) during pregnancy. For leisure-time physical activity the respective summary RRs for high versus low activity was 0.78 (95 % CI 0.61-1.00, I2 = 47 %, n = 8) before pregnancy, and it was 0.80 (95 % CI 0.64-1.00, I2 = 17 %, n = 17) during pregnancy. The summary RR for pre-pregnancy activity was 0.70 (95 % CI 0.49-1.01, I2 = 72.6 %, n = 3) per increment of 5 h/week and for activity during pregnancy was 0.98 (95 % CI 0.87-1.09, I2 = 0 %, n = 3) per 5 h/week. There was evidence of a nonlinear association between physical activity before pregnancy and the risk of gestational diabetes mellitus, pnonlinearity = 0.005, with a slightly steeper association at lower levels of activity although further reductions in risk were observed up to 10 h/week. There was also evidence of nonlinearity for physical activity in early pregnancy, pnonlinearity = 0.008, with no further reduction in risk above 8 h/week. There was some indication of inverse associations between walking (before and during pregnancy) and vigorous activity (before pregnancy) and the risk of gestational diabetes mellitus. This meta-analysis suggests that there is a significant inverse association between physical activity before pregnancy and in early pregnancy and the risk of gestational diabetes mellitus. Further studies are needed to clarify the association between specific types and intensities of activity and gestational diabetes mellitus.

Diet and exercise interventions for preventing gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with a wide range of adverse health consequences for women and their babies in the short and long term. With an increasing prevalence of GDM worldwide, there is an urgent need to assess strategies for GDM prevention, such as combined diet and exercise interventions.

OBJECTIVES

To assess the effects of combined diet and exercise interventions for preventing GDM and associated adverse health consequences for women and their babies.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (11 February 2014) and reference lists of retrieved studies. We updated the search in February 2015 but these results have not yet been incorporated and are awaiting classification.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and cluster-RCTs assessing the effects of interventions that included diet and exercise components. We included studies where combined diet and exercise interventions were compared with no intervention (i.e. standard care).We planned to also compare diet and exercise interventions with alternative diet and/or exercise interventions but no trials were identified for this comparison.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data and assessed the risk of bias of the included studies. Data were checked for accuracy.

MAIN RESULTS

We included 13 randomised controlled trials (involving 4983 women and their babies). We assessed the included trials as being of moderate risk of bias overall.When comparing women receiving a diet and exercise intervention with those receiving no intervention, there was no clear difference in the risk of developing GDM (average risk ratio (RR) 0.92, 95% confidence interval (CI) 0.68 to 1.23; 11 trials, 3744 women), caesarean section (RR 0.92, 95% CI 0.83 to 1.01; seven trials, 3246 women), or large-for-gestational age (RR 0.90, 95% CI 0.77 to 1.05; 2950 infants). Only one trial reported on perinatal mortality, and found no clear difference in the risk of stillbirth (RR 0.99, 95% CI 0.29 to 3.42; 2202 fetuses) or neonatal death (RR 0.99, 95% CI 0.06 to 15.85; 2202 neonates).Very few differences were shown between groups for the review's secondary outcomes, including for induction of labour, perineal trauma, pre-eclampsia, postpartum haemorrhage and infection, macrosomia, birthweight, small-for-gestational age, ponderal index, neonatal hypoglycaemia requiring treatment, hyperbilirubinaemia requiring treatment, shoulder dystocia, bone fracture or nerve palsy. Women receiving a combined diet and exercise intervention were, however, found to have a reduced risk of preterm birth compared with women receiving no intervention (RR 0.71, 95% CI 0.55 to 0.93; five trials, 2713 women).A trend towards reduced weight gain during pregnancy was shown for women receiving the combined diet and exercise intervention (mean difference (MD) -0.76 kg, 95% CI -1.55 to 0.03; eight trials, 2707 women; P = 0.06, random-effects); but no clear difference in postnatal weight retention was observed overall.In relation to adherence to the interventions, a number of trials that reported on behaviour modifications showed benefits in diet- (5/8 trials) and physical activity- (4/8 trials) related behaviours for women receiving the combined diet and exercise intervention, compared with women receiving no intervention; however there was notable variation across trials in outcomes measured and results observed. Only two trials reported on well-being and quality of life of women, and did not observe differences between groups for these outcomes.Very few trials reported on outcomes relating to the use of health services, although one trial suggested a reduced length of antenatal hospital stay for women receiving a combined diet and exercise intervention (MD -0.27 days, 95% CI -0.49 to -0.05; 2153 women).No information was available on outcomes for the infant as a child or adult, or for most longer-term outcomes for the mother.

AUTHORS' CONCLUSIONS

There are limitations associated with the available RCT evidence on the effects of combined diet and exercise interventions during pregnancy for preventing GDM. Results from 13 RCTs (of moderate quality) suggest no clear difference in the risk of developing GDM for women receiving a combined diet and exercise intervention compared with women receiving no intervention. However, the ability to draw firm conclusions was limited by variations in the quality of trials, characteristics of the interventions and populations assessed, and outcome definitions between trials.Based on the data currently available, conclusive evidence is not available to guide practice. Further large, well-designed RCTs, addressing the limitations of previous studies, are needed to assess the effects of combined interventions on preventing GDM and other relevant pregnancy outcomes including caesarean birth, large-for-gestational age and perinatal mortality. Health service utilisation and costs, and longer-term outcomes for mothers and their babies should be included. We identified another 16 trials which are ongoing and we will consider these for inclusion in the next update of this review.

Expression of PI3-K, PKB and GSK-3 β in the skeletal muscle tissue of gestational diabetes mellitus

OBJECTIVE

To analyze the expression of phosphatidylinositol 3 kinase (PI3-K), protein kinase B (PKB) and glycogen synthase kinase 3 beta (GSK-3 β) in skeletal muscle tissue of gestational diabetes mellitus (GDM).

METHODS

A total of 90 cases of pregnant women were divided into observation group and control group according to the occurrence of GDM with 45 cases in either, and the expression of PI3-K, PKB, GSK-3 β mRNA expression in skeletal muscle tissue was compared between two groups.

RESULTS

The total PI3-K p85 protein was significantly higher in the observation group compared with the control group, the activity of PI3-K was lower than that of the latter; The total PKB, GSK-3 β protein in skeletal tissue had no significant difference between two groups, while the serine phosphorylation levels of PKB and GSK-3β were significantly lower in observation group compared with the control group.

CONCLUSIONS

The downregulation of PI3-K, PKB and GSK-3βin skeletal tissue of GDM caused by phosphorylation dysfunction of signaling molecules is the reason for insulin resistance and transporter function decline which lead to GDM.

Supervised exercise-based intervention to prevent excessive gestational weight gain: a randomized controlled trial

OBJECTIVE

To study the effect on maternal weight gain of a supervised light- to moderate-intensity exercise-based intervention performed from the ninth week of pregnancy.

PARTICIPANTS AND METHODS

A total of 962 healthy pregnant women were randomly assigned to a standard care or exercise intervention group conducted between September 1, 2007, and January 31, 2011. The intervention included light- to moderate-intensity aerobic and resistance exercises performed 3 days a week (50-55 minutes per session). Excessive gestational weight gain was calculated on the basis of the 2009 Institute of Medicine (IOM) recommendations. Gestational body weight gain was calculated on the basis of the weight measured at the first prenatal visit (fifth to sixth weeks of gestation) and weight measured at the last visit to the clinic before delivery. Women were categorized into normal weight or overweight or obese.

RESULTS

Women in the intervention group gained less weight (adjusted mean difference, 1.039 kg; 95% CI, 0.534-1.545 kg; P<.001) and were less likely to gain weight above the IOM recommendations (odds ratio, 0.625; 95% CI, 0.461-0.847) compared with those in the standard care group. The main treatment effects according to body mass index category were that normal weight women in the intervention group gained less weight (adjusted mean difference, 1.393 kg; 95% CI, 0.813-1.972 kg; P<.001) and were less likely to gain weight above the IOM recommendations (odds ratio, 0.508; 95% CI, 0.334-0.774) than normal weight women who received standard care. No significant treatment effect was observed in overweight or obese women.

CONCLUSION

Supervised exercise of light to moderate intensity can be used to prevent excessive gestational weight gain, especially in normal weight women.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01790347.

Physical activity during pregnancy and the risk of gestational diabetes mellitus: a systematic review and meta-analysis of randomised controlled trials

OBJECTIVES

We performed a systematic review and meta-analysis to assess the effects of physical activity in preventing gestational diabetes mellitus (GDM).

SEARCH STRATEGY

We searched the literature in six electronic databases and bibliographies of relevant articles.

SELECTION CRITERIA

We included randomised controlled trials on pregnant women who did not have GDM and other complications previously and had increased physical activity as the only intervention. The risk of developing GDM was documented separately for the intervention and control groups.

DATA COLLECTION AND ANALYSIS

Two reviewers extracted data and assessed quality independently. Data from the included trials were combined using a fixed-effects model. The effect size was expressed as relative risk (RR) and 95% CI.

MAIN RESULTS

Of the 1110 studies identified, six randomised controlled trials met the inclusion criteria. In three trials, the incidence of GDM was lower in the intervention group than in the control group, whereas two trials showed a higher incidence of GDM in the intervention group and the remaining trial found no GDM in either the intervention or control group. The meta-analysis resulted in a relative risk (RR) of GDM of 0.91 (95% CI 0.57 to 1.44), suggesting no significant difference in the risk of developing GDM between the intervention and the control groups. No indication of publication bias was found.

CONCLUSIONS

Evidence was insufficient to suggest that physical activity during pregnancy might be effective to lower the risk of developing GDM.

A qualitative study of women's perceptions of provider advice about diet and physical activity during pregnancy

OBJECTIVE

The purpose of this qualitative study was to gather insights into pregnant women's experiences with provider advice about diet and physical activity.

METHODS

We conducted a series of 13 focus groups with a total of 58 pregnant African American, Caucasian, and Hispanic women of varying body sizes. Statements were independently coded, reduced, and then reconstructed to identify overarching themes with the assistance of ATLAS/ti software.

RESULTS

Mean gestational age at the time of the focus groups was 30 weeks. Women commonly reported overwhelming and confusing diet advice and a paucity of physical activity advice that was largely limited to walking. Many reported following advice; when advice was not followed, it was because women disagreed with it or simply did not want to do it.

CONCLUSION

Women would benefit from more clear guidance from physicians and other providers regarding dietary choices and physical activity in pregnancy.

PRACTICE IMPLICATIONS

Providers should make dietary and physical activity advice in pregnancy more clear and individualized and offer such guidance multiple times throughout pregnancy.

Physical activity during pregnancy and risk of hyperglycemia

OBJECTIVE

To determine the association between moderate and vigorous physical activities (MVPA) during midpregnancy and the risk of hyperglycemia.

METHODS

Data were from 1437 pregnant women. Frequency, duration, and intensity of MVPA during the previous 7 days were collected via questionnaire at 17-22 weeks' gestation. Modes of MVPA included work, recreation, transportation, caregiving, and indoor and outdoor household activities. Hyperglycemia was defined as a glucose concentration ≥130 mg/dL on a 1-hour, 50-g glucose challenge test or gestational diabetes mellitus (GDM) assessed at ~27 weeks' gestation. Multivariable Poisson regression estimated risks of hyperglycemia associated with total and mode-specific MVPA.

RESULTS

There were 269 women (18.7%) with hyperglycemia. Any metabolic equivalent (MET) hours/week of recreational MVPA was associated with a 27% lower risk of hyperglycemia (adjusted relative risk, [aRR] 0.73, 95% confidence interval [95%CI] 0.54-0.99). Multiplicative interaction terms were significant for prepregnancy body mass index (BMI) and recreational MVPA (p=0.01). Among women with prepregnancy BMI <25 kg/m(2), recreational MVPA was associated with a 48% lower risk of hyperglycemia (aRR 0.52, 95%CI 0.33-0.83) compared to women who reported none. There was no association of hyperglycemia and recreational MVPA among women with prepregnancy BMI <25 kg/m(2).

CONCLUSIONS

Recreational MVPA during pregnancy is associated with a lower risk of hyperglycemia, specifically among women with prepregnancy BMI <25 kg/m(2). Further research is warranted to determine recommended amounts and intensities of physical activity and to discern whether there are differences in the effects of physical activity between specific modes of physical activity or among subgroups of women in relation to hyperglycemia.

Gestational Diabetes

Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy and is strongly related to subsequent risk of type 2 diabetes. The epidemics of obesity and diabetes and the increasing incidence of GDM in recent years highlight the importance of preventing GDM among women at high risk to avoid the associated short- and long-term adverse health outcomes for both mothers and their offspring. Indeed, women may be more likely to adopt healthy lifestyle habits during pregnancy and maintain these habits into the postpartum period. Although there is substantial evidence that targeting at-risk groups for type 2 diabetes prevention is effective if lifestyle changes are made, relatively little attention has been paid to the prevention of GDM. Therefore, the objective of this article is to review the scientific evidence regarding the association between modifiable risk factors and GDM; discuss how lifestyle interventions, including weight management through diet and exercise could be successful in reducing the risk for GDM; and provide recommendations for future lifestyle intervention programs with a focus on translation and dissemination of research findings.

Physical activity and dietary behaviors associated with weight gain and impaired glucose tolerance among pregnant Latinas

Pregnancy has been proposed as a critical period for the development of subsequent maternal overweight and/or obesity. Excessive gestational weight gain is, in turn, associated with maternal complications such as cesarean delivery, hypertension, preeclampsia, impaired glucose tolerance, and gestational diabetes mellitus. Although there is substantial evidence that targeting at-risk groups for type 2 diabetes prevention is effective if lifestyle changes are made, relatively little attention has been paid to the prevention of excessive gestational weight gain and impaired glucose tolerance during pregnancy. Latinos are the largest minority group in the United States, with the highest birth and immigration rates of any minority group and are disproportionately affected by overweight and obesity. However, due to cultural factors, socioeconomic factors, and language barriers, Latinos have had limited access to public health interventions that promote healthy lifestyles. Therefore, the objective of this article is to review the scientific evidence regarding the association between physical activity, dietary behaviors, and gestational weight gain and impaired glucose tolerance among Latinas. A second objective is to discuss how lifestyle interventions including weight management through diet and exercise could be successful in reducing the risk of excessive gestational weight gain and gestational diabetes mellitus. Finally, recommendations are provided for future lifestyle intervention programs in this population with a focus on translation and dissemination of research findings.

Exercise guidelines in pregnancy: new perspectives

In 2002, the American College of Obstetricians and Gynecologists published exercise guidelines for pregnancy, which suggested that in the absence of medical or obstetric complications, 30 minutes or more of moderate exercise a day on most, if not all, days of the week is recommended for pregnant women. However, these guidelines did not define 'moderate intensity' or the specific amount of weekly caloric expenditure from physical activity required. Recent research has determined that increasing physical activity energy expenditure to a minimum of 16 metabolic equivalent task (MET) hours per week, or preferably 28 MET hours per week, and increasing exercise intensity to ≥60% of heart rate reserve during pregnancy, reduces the risk of gestational diabetes mellitus and perhaps hypertensive disorders of pregnancy (i.e. gestational hypertension and pre-eclampsia) compared with less vigorous exercise. To achieve the target expenditure of 28 MET hours per week, one could walk at 3.2 km per hour for 11.2 hours per week (2.5 METs, light intensity), or preferably exercise on a stationary bicycle for 4.7 hours per week (∼6-7 METs, vigorous intensity). The more vigorous the exercise, the less total time of exercise is required per week, resulting in ≥60% reduction in total exercise time compared with light intensity exercise. Light muscle strengthening performed over the second and third trimester of pregnancy has minimal effects on a newborn infant's body size and overall health. On the basis of this and other information, updated recommendations for exercise in pregnancy are suggested.

Physical activity before and during pregnancy and risk of gestational diabetes mellitus: a meta-analysis

OBJECTIVE

Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy and is associated with a substantially elevated risk of adverse health outcomes for both mothers and offspring. Physical activity may contribute to the prevention of GDM and thus is crucial for dissecting the vicious circle involving GDM, childhood obesity, and adulthood obesity, and diabetes. Therefore, we aimed to systematically review and synthesize the current evidence on the relation between physical activity and the development of GDM.

RESEARCH DESIGN AND METHODS

Medline, EMBASE, and Cochrane Reviews were searched from inception to 31 March 2010. Studies assessing the relationship between physical activity and subsequent development of GDM were included. Characteristics including study design, country, GDM diagnostic criteria, ascertainment of physical activity, timing of exposure (prepregnancy or early pregnancy), adjusted relative risks, CIs, and statistical methods were extracted independently by two reviewers.

RESULTS

Our search identified seven prepregnancy and five early pregnancy studies, including five prospective cohorts, two retrospective case-control studies, and two cross-sectional study designs. Prepregnancy physical activity was assessed in 34,929 total participants, which included 2,813 cases of GDM, giving a pooled odds ratio (OR) of 0.45 (95% CI 0.28-0.75) when the highest versus lowest categories were compared. Exercise in early pregnancy was assessed in 4,401 total participants, which included 361 cases of GDM, and was also significantly protective (0.76 [95% CI 0.70-0.83]).

CONCLUSIONS

Higher levels of physical activity before pregnancy or in early pregnancy are associated with a significantly lower risk of developing GDM.