Significant changes in physical activity among pregnant women in the UK as assessed by accelerometry and self-reported activity

Four Days Are Enough to Provide a Reliable Daily Step Count in Mild to Moderate Parkinson's Disease through a Commercial Smartwatch

Daily steps could be a valuable indicator of real-world ambulation in Parkinson's disease (PD). Nonetheless, no study to date has investigated the minimum number of days required to reliably estimate the average daily steps through commercial smartwatches in people with PD. Fifty-six patients were monitored through a commercial smartwatch for 5 consecutive days. The total daily steps for each day was recorded and the average daily steps was calculated as well as the working and weekend days average steps. The intraclass correlation coefficient (ICC) (3,k), standard error of measurement (SEM), Bland-Altman statistics, and minimum detectable change (MDC) were used to evaluate the reliability of the step count for every combination of 2-5 days. The threshold for acceptability was set at an ICC ≥ 0.8 with a lower bound of CI 95% ≥ 0.75 and a SAM < 10%. ANOVA and Mann-Whitney tests were used to compare steps across the days and between the working and weekend days, respectively. Four days were needed to achieve an acceptable reliability (ICC range: 0.84-0.90; SAM range: 7.8-9.4%). In addition, daily steps did not significantly differ across the days and between the working and weekend days. These findings could support the use of step count as a walking activity index and could be relevant to developing monitoring, preventive, and rehabilitation strategies for people with PD.

Evaluation of Physical Activity Level and Related Factors in Pregnancy During the COVID-19 Period

Objectives: It was aimed to determine the level of physical activity and related factors in pregnant women. Methods: The study is a mixed methods study. The participants are women applied to the pregnancy outpatient clinic of a hospital. The level of physical activity was assessed with the Pregnancy Physical Activity Questionnaire. Sociodemographic questions and seven questions of the International Physical Activity Environment Module were asked. Besides, in-depth interviews were conducted with 14 women. Results: The study was conducted with 304 women. The median age was 29.0 (18.0-40.0) years. The mean total activity and sedentary activity scores were 195.8 ± 107.9 and 37.22 ± 31.08 MET-hours/week, respectively. Pregnant women were mostly involved in light-intensity and housework/caregiving activities. Most of the participants mentioned that they were less active than pre-pregnancy period. The most common reasons for being less active were weakness, fatigue, lack of time and complaints such as low back pain and nausea. Conclusion: More than half of the pregnant women mentioned that they were less active during pregnancy. Thus, interventions should be planned to increase physical activity level of pregnant women.

[Fit for Two - A Study of Sedentary Behavior and Physical Activity During Pregnancy]

BACKGROUND

In the pilot study sedentary behavior and physical activity were measured in pregnant women using an accelerometer.

METHODS

A total of 32 pregnant women were enrolled in the study; eleven of them were included in the first trimester. The defined wearing periods for the accelerometer in the first, second and third trimester were weeks 9-12, 23-26, and 36-39, respectively. A self-administered survey was carried out after a 7-day measurement.

RESULTS

The pregnant women were on average 30 years old, 50% were nulliparous, and 68.8% had a high school diploma. The accelerometer was worn on average of 13 hours per day. Sedentary behavior was recorded more than half of the wearing time for all trimesters. The proportion of time spent in moderate-to-vigorous activity was highest at 4.7% in the second trimester, compared to 2.5% in the first and 3.8% in the third. A proportion of women, ranging from 32% in the first, 54% in the second, and 58% in the third trimester did reach the levels of PA recommended by the guidelines. Nulliparous women in the second and third trimester spent twice as much time in moderate-to-vigorous activities compared to multiparous women.

CONCLUSION

Pregnant women spent more than half of the monitored day in sedentary behaviors. Half of them did meet the recommendations for physical activity in the second and third trimester. The results show that sedentary behavior and physical activity should be considered more in clinical practice and research to motivate pregnant women to adopt a physically active lifestyle.

Comparison of the Portuguese Version of the Pregnancy Physical Activity Questionnaire (PPAQ) with Accelerometry for Classifying Physical Activity among Pregnant Women with Obesity

In recent years, the number of pregnant women with obesity has increased exponentially; thus, it is important to evaluate and characterize the physical activity levels of this specific group. The aim of this study is to evaluate the reliability and validity of the Portuguese version of the Physical Activity and Pregnancy Questionnaire and Pregnancy Questionnaire in pregnant women with obesity and to classify physical activity using the Physical Activity and Pregnancy Questionnaire and accelerometry. An analytical observational study was carried out between May and August of 2019 at the University Hospital Center of São João, with a sample of 31 pregnant women with obesity (30.9 ± 4.6 years 36.5 ± 4.6 kg/m² of BMI and 21.5 ± 9 gestational weeks). The physical activity of participants was evaluated using an accelerometer and Physical Activity and Pregnancy Questionnaire at two time points (the first visit at the moment of consultation and the second seven days after, with accelerometer retest), the interclass correlation coefficient was used to test reliability between the Physical Activity and Pregnancy Questionnaire filled out at visit1 and the Physical Activity and Pregnancy Questionnaire filled out at visit2, and Pearson's correlation was used to determine validity between the Physical Activity and Pregnancy Questionnaire and accelerometry. The interclass correlation coefficient values for total activity were 0.95, 0.97 for moderate and 0.58 for vigorous intensities. It ranged from 0.74 for sports/exercise to 0.96 for domestic activities. The Pearson's correlations showed that the Physical Activity and Pregnancy Questionnaire is moderately valid for moderate intensity (r = 0.435). A total of 67.7% of the pregnant women complied with international physical activity recommendations.

Longitudinal Changes in Physical Activity during Pregnancy: National Institute of Child Health and Human Development Fetal Growth Studies

INTRODUCTION

Exercise in pregnancy is associated with many perinatal benefits, but patterns of home, work, and commuting activity are not well described. We investigated longitudinal activity in singleton and twin pregnancy by activity domain and maternal characteristics.

METHODS

In the National Institute of Child Health and Human Development Fetal Growth Studies cohorts, 2778 women with singleton and 169 women with twin gestations reported activity using the Pregnancy Physical Activity Questionnaire at up to six or seven study visits, respectively. Metabolic equivalent of task-hours per week (MET-h·wk -1 ) was calculated from reported activity. Baseline measurements (obtained between 10 and 13 wk) reflected past year activity. Linear mixed models estimated MET-h·wk -1 by domain (household/childcare, occupational, inactive, transportation, sports/exercise), self-reported race/ethnicity (non-Hispanic White, non-Hispanic Black, Hispanic, Asian/Pacific Islander), prepregnancy body mass index (<25, 25 to < 30, ≥30 kg·m -2 ), parity (0, ≥1), baseline activity (quartiles), and plurality (singleton, twin).

RESULTS

Household/caregiving activity made up the largest fraction of reported MET-h·wk -1 at baseline (42%), followed by occupational activity (28%). Median summed activity declined 47%, from 297 to 157 MET-h·wk -1 , between 10 and 40 wk, largely driven by changes in household/caregiving (44% decline), and occupational activity (63% decline). Sports/exercise activity declined 55% but constituted only 5% of reported MET-h·wk -1 at baseline. At baseline, non-Hispanic Black women reported significantly higher activity than non-Hispanic White or Hispanic women, but differences did not persist across pregnancy. Across gestation nulliparous women reported significantly lower activity than parous women. Women with singleton gestations reported significantly more activity than women with twins from weeks 26 to 38. Baseline activity level was strongly associated with later activity levels.

CONCLUSIONS

Measuring domains of activity beyond exercise, and collecting longitudinal measurements, is necessary to fully describe activity in diverse populations of pregnant women.

Level of Physical Activity in Pregnant Populations from Different Geographic Regions: A Systematic Review

The aim of this study was to examine the level of physical activity during pregnancy in different populations worldwide. An intensive search was carried out from February until May 2021. The inclusion criteria were original studies of healthy pregnant women, and the main study variable was the assessment of physical activity. A total of 110 out of 1451 studies were assessed for inclusion, using the Newcastle–Ottawa Scale for quality, and for the risk of bias. The 44 analyzed articles were divided into 5 tables according to the characteristics of the intervention and the validated instrument used to measure physical activity (PA). A total of 59.09% of the studies indicated that participants had a low level of physical activity during pregnancy. In addition, the median quality score of the studies was 7.12, and 77.27% of the studies were cataloged as having a high-quality score. Although international guidelines recommend that women without a contraindication engage in prenatal physical activity, the results of the present study show that the level of PA is too low for women to achieve scientifically proven maternal-fetal benefits. Failure to achieve the recommended levels of weekly physical activity could pose significant risks to maternal well-being.

Does Prenatal Physical Activity Affect the Occurrence of Postnatal Anxiety and Depression? Longitudinal Study

The aim of the foregoing study was to assess whether physical activity during pregnancy affects the occurrence of anxiety and depression during pregnancy, postpartum and 6 months following childbirth. This study tried to answer the following questions: How was the incidence of depression and anxiety different in the pre- and postpartum periods? What intensity level of physical activity protects against the symptoms of anxiety and depression? Does the time spent engaged in sedentary activities and MVPA affect the occurrence of depression and anxiety before and after childbirth? The study group under analysis consisted of 187 women aged 19–41 years. The research was conducted between April 2016 and November 2020. The study was divided into four stages: T0—qualification to participate in the study; T1—medical history acquisition, consisting of a short questionnaire and two long questionnaires (the Edinburgh Postnatal Depression Scale (EPDS) and General Anxiety Disorder-7 (GAD-7)), as well as an assessment of 7-day physical activity using Actigraph accelerometers during the pregnancy; T2—the completion of the EPDS and GAD-7 questionnaires after the birth; T3—the completion of the EPDS and GAD-7 questionnaire 6 months after giving birth. The obtained results were statistically processed in the Statistica 13.3 software package. A significance level of p < 0.05 was assumed. The highest percentage of depression occurred immediately after the delivery, followed by 6 months after delivery, and the smallest number of women suffered from depression before the birth (p < 0.001). The analysis of correlations of physical activity with anxiety symptoms did not show significant correlations. However, the situation is different in the case of depression symptoms. Women taking fewer steps before delivery showed a greater tendency to develop depressive symptoms before, immediately after and 6 months after the delivery (p < 0.001). Women who were less active (took fewer steps per day, spent less time in moderate-to-vigorous physical (MVPA) activities or spent more time being sedentary) showed symptoms of depression on the EPDS scale. It appeared that those with severe anxiety symptoms had the highest sedentary time scores before the delivery (p = 0.020). Reduced physical activity promotes the onset of postnatal depression, while being active reduces this risk. Interestingly, even light physical activity “protects” against the occurrence of depression and is better than sedentary activities. Such clear conclusions cannot be drawn in relation to anxiety symptoms. Sedentary behaviour may promote anxiety symptoms immediately after childbirth, but this study should be continued in order to confirm it during other time periods.

Influence of the degree of adherence to the mediterranean diet and its components on cardiometabolic risk during pregnancy. The GESTAFIT project

BACKGROUND AND AIMS

Studies regarding dietary patterns and cardiometabolic risk markers during pregnancy are scarce. The aim of the present study was to analyse whether different degrees of adherence to the Mediterranean diet (MD) and the MD components were associated with cardiometabolic markers and a clustered cardiometabolic risk during pregnancy.

METHODS AND RESULTS

This study comprised 119 pregnant women from the GEStation and FITness (GESTAFIT) project. Dietary habits were assessed with a food frequency questionnaire at the 16th and 34th gestational weeks (g.w.). The Mediterranean Diet Score was employed to assess MD adherence. The following cardiometabolic markers were assessed: pre-pregnancy body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting glucose, triglycerides and high-density lipoprotein cholesterol (HDL-C). A greater MD adherence was associated with a better cardiometabolic status in cross-sectional (16th g.w. and 34th g.w.) and prospective analyses (MD adherence at the 16th g.w. and cardiometabolic markers at the 34th g.w.; SBP, DBP and HDL-C; all, p < 0.05). Participants with the highest MD adherence (Tertile 3) had a lower clustered cardiometabolic risk than those with the lowest MD adherence (Tertile 1) at the 16th and 34th g.w. (both, p < 0.05). A higher intake of fruits, vegetables and fish and a lower intake of refined cereals and red meat and subproducts were associated with a lower cardiometabolic risk during pregnancy (all, p < 0.05).

CONCLUSION

A higher MD adherence, a greater intake of fruits, vegetables and fish and a lower intake of refined cereals and red meat and subproducts showed a cardioprotective effect throughout gestation.

Location, Location, Location: Accelerometer Placement Affects Steps-Based Physical Activity Outcomes During Pregnancy and Postpartum

As pregnancy progresses, physical changes may affect physical activity (PA) measurement validity. n = 11 pregnant women (30.1 ± 3.8 years) wore ActiGraph GT3X+ accelerometers on the right hip, right ankle, and non-dominant wrist for 3-7 days during the second and third trimesters (21 and 32 weeks, respectively) and 12 weeks postpartum. Data were downloaded into 60-second epochs from which stepping cadence was calculated; repeated-measures analysis of variance was used to determine significant differences among placements. At all time points, the wrist accelerometer measured significantly more daily steps (9930-10 452 steps/d) and faster average stepping cadence (14.5-14.6 steps/min) than either the hip (4972-5944 steps/d, 7.1-8.6 steps/min) or ankle (7161-8205 steps/d, 10.3-11.9 steps/min) placement, while moderate- to vigorous-intensity activity at the wrist (1.2-1.7 min/d) was significantly less than either hip (3.0-5.9 min/d) or ankle (6.1-7.3 min/d). Steps, cadence, and counts were significantly lower for the hip than the ankle at all time points. Kappa calculated for agreement in intensity classification between the various pairwise comparisons ranged from .06 to .41, with Kappa for hip-ankle agreement (.34-.41) significantly higher than for wrist-ankle (.09-.11) or wrist-hip (.06-.16). These data indicate that wrist accelerometer placement during pregnancy likely results in over counting of PA parameters and should be used with caution.

Sleep and physical activity from before conception to the end of pregnancy in healthy women: a longitudinal actigraphy study

BACKGROUND

Sleep and physical activity changes are common in pregnancy, but longitudinal data starting before conception are scarce. Our aim was to determine the changes of the daily total sleep time (TST) and physical activity duration (PAD) from before conception to end of pregnancies in respect of pregestational maternal factors.

METHODS

This longitudinal observational study formed part of the CONIMPREG research project and recruited healthy women planning to become pregnant. Sleep and physical activity were recorded around-the-clock for ≥4 days via actigraphy before conception and during each trimester of pregnancy. Data were adjusted according to pregestational maternal body composition, parity and age.

RESULTS

Among 123 women with eligible data, the unadjusted mean (95% confidence interval) TST increased from 415.3 min (405.5-425.2 min) before conception to 458.0 min (445.4-470.6 min) in the 1st trimester, remaining high through the 2nd and 3rd trimesters. Variation was substantial before conception (±2SD range: 307-523 min). The unadjusted mean PAD before conception was 363.7 min (±2SD range: 120-608 min), decreasing sharply to 262.1 min in the first trimester and more gradually thereafter. Vigorous and moderate activity decreased more than light activity. TST and PAD were significantly associated with age, parity, and pregestational body fat percentage; lean body mass was negatively correlated with TST. Results were generally unaffected by seasonal variations.

CONCLUSION

Marked variations were found in pregestational TST and PAD. Healthy women slept ≥30 min longer during pregnancy, while PAD decreased by ≥ 90 min in early pregnancy and continued to decrease thereafter.

Physical Activity-Related Metabolites Are Associated with Mortality: Findings from the Atherosclerosis Risk in Communities (ARIC) Study

Habitual physical activity can diminish the risk of premature death. Identifying a pattern of metabolites related to physical activity may advance our understanding of disease etiology. We quantified 245 serum metabolites in 3802 participants from the Atherosclerosis Risk in Communities (ARIC) study using chromatography-mass spectrometry. We regressed self-reported moderate-to-vigorous intensity leisure-time physical activity (LTPA) against each metabolite, adjusting for traditional risk factors. A standardized metabolite risk score (MRS) was constructed to examine its association with all-cause mortality using the Cox proportional hazard model. We identified 10 metabolites associated with LTPA (p < 2.04 × 10^-4) and established that an increase of one unit of the metabolic equivalent of task-hours per week (MET·hr·wk^-1) in LTPA was associated with a 0.012 SD increase in MRS. During a median of 27.5 years of follow-up, we observed 1928 deaths. One SD increase of MRS was associated with a 10% lower risk of death (HR = 0.90, 95% CI: 0.85-0.95). The highest vs. the lowest MRS quintile rank was associated with a 22% reduced risk of death (HR = 0.78, 95% CI: 0.62-0.94). The effects were consistent across race and sex groups. In summary, we identified a set of metabolites associated with LTPA and an MRS associated with a lower risk of death. Our study provides novel insights into the potential mechanisms underlying the health impacts of physical activity.

Feasibility and Acceptability of a Counseling- and mHealth-Based Physical Activity Intervention for Pregnant Women With Diabetes: The Fit for Two Pilot Study

BACKGROUND

Diabetes during pregnancy poses serious health risks to both mother and child. Regular physical activity can reduce these risks, yet few clinic-based interventions of physical activity for pregnant women with diabetes have been attempted.

OBJECTIVE

The purpose of this single-arm pilot trial is to assess the feasibility and acceptability, and explore the potential efficacy of a counseling- and mobile health-based physical activity intervention for pregnant women with diabetes.

METHODS

Participants (N=17) who had type 2 or gestational diabetes, could read and speak in English or Spanish, and were between 10 and 27 weeks of gestation were recruited from the University of California San Diego Diabetes and Pregnancy Program. Participants engaged in a one-on-one counseling and goal-setting session immediately following a clinic visit with their physician. They were given a Fitbit and shown how to use the Fitbit app, including entering personalized step goals, and were encouraged to build up to 10,000 daily steps. Daily steps were recorded for 12 weeks, until they were 36 weeks' gestation, or until 1 week before they gave birth, whichever came first. Feasibility was measured by recruitment, retention, and adherence, and acceptability was measured using consumer satisfaction questionnaires and follow-up interviews. Potential efficacy was explored by examining changes in daily steps over time.

RESULTS

The participants were primarily Hispanic (13/17, 76%), had public insurance (15/17, 88%), and had type 2 diabetes (12/17, 71%). Of the 17 patients who began the intervention, 76% (13/17) completed a follow-up visit, and 71% (12/17) continued wearing the Fitbit regularly after 8 weeks in the intervention. Adherence in wearing the Fitbit was relatively high, with a median wear adherence of 90% of days. The intervention was generally well accepted, with 85% (11/13) indicating that they were motivated to exercise more following the counseling session, 85% (11/13) indicating that the Fitbit helped increase their activity, and 92% (12/13) recommending the program overall. Mean daily steps increased from baseline (mean 6122, SD 2439) to week 3 (mean 6269, SD 2166) and then decreased through week 12 (mean 4191, SD 2228).

CONCLUSIONS

High acceptability, retention, and adherence suggest that this may be a promising approach to delivering a simple, low-burden intervention in a clinical setting to a high-risk, underserved population. A randomized controlled trial is needed to determine whether this approach is effective in slowing the reduction in activity typically seen throughout pregnancy.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03302377; https://clinicaltrials.gov/ct2/show/NCT03302377.

Effect of Antenatal Exercises, Including Yoga, on the Course of Labor, Delivery and Pregnancy: A Retrospective Study

Background: Delivering a child is a very stressful experience for women. Pregnancy and labor entail complex events that are unique to each individual female. The management of labor pain is often done using analgesics and anesthesia, which have been shown to have some side effects. More comprehensive data are needed to provide clinically significant evidence for clinicians to confidently prescribe exercises to patients. This study was done to evaluate the effect of antenatal exercises, including yoga, on the course of labor, delivery, and pregnancy outcomes. Methods: A retrospective study was conducted among 200 primiparous subjects (aged 20-40). A questionnaire was provided to the subjects to obtain their demographic and obstetrical information 6 weeks after delivery, and their hospital records were also assessed for further details. Based on the nature and details obtained for the antenatal exercises, subjects were divided into two groups: control and exercise. Outcome measures included the need for labor induction, self-perceived pain and perceived exertion during labor, duration and nature of the delivery, newborn infant weight, maternal weight gain, history of back pain, and post-partum recovery. The total maternal weight gain (in kilograms) was calculated from weight at 6 weeks after delivery minus the weight at 12-14 weeks of gestation. Back pain during pregnancy and self-perceived labor pain were measured using a visual analog scale (VAS). The overall perceived exertion during labor was measured using an adapted Borg scale for perceived effort. Results: The subjects who followed regular antenatal exercises, including yoga, had significantly lower rates of cesarean section, lower weight gain, higher newborn infant weight, lower pain and overall discomfort during labor, lower back pain throughout pregnancy, and earlier post-partum recovery compared to those who did no specific exercises or only walked during pregnancy. Conclusions: This retrospective study showed that regular antenatal exercises, including yoga, result in better outcomes related to the course of labor, delivery, and pregnancy. These results notably indicated that pregnant women should be active throughout pregnancy and follow a supervised exercise program that includes yoga unless contraindicated. We require further large-scale prospective studies and quasi-experimental trials to confirm the observed findings.

Less sedentary time is associated with a more favourable glucose-insulin axis in obese pregnant women-a secondary analysis of the DALI study

Background/objectives

Obese pregnant women are at high risk of developing gestational diabetes mellitus (GDM), which might be reduced by sufficient physical activity (PA) and reduced sedentary time (ST). We assessed whether PA and ST are longitudinally associated with the glucose-insulin axis in obese pregnant women.

Subjects/methods

In this secondary analysis of the DALI (vitamin D And Lifestyle Intervention for gestational diabetes mellitus prevention) study, pregnant women, <20 weeks gestation, with a pre-pregnancy body mass index (BMI) ≥ 29 kg/m², without GDM on entry were included. Time spent in moderate-to-vigorous PA (MVPA) and ST were measured objectively with accelerometers at <20 weeks, 24–28 weeks and 35–37 weeks of gestation. Fasting glucose (mmol/l) and insulin (mU/l), insulin resistance (HOMA-IR) and first-phase and second-phase insulin release (Stumvoll first and second phase) were assessed at the same time. Linear mixed regression models were used to calculate between-participant differences and within-participant changes over time. Analyses were adjusted for gestational age, randomisation, pre-pregnancy BMI, education and age. MVPA, Insulin, HOMA-IR and Stumvoll first and second phase were log-transformed for analyses due to skewness.

Results

232 women were included in the analysis. Concerning differences between participants, more ST was associated with higher fasting glucose (Estimate: 0.008; 95% CI: 0.002, 0.014), fasting insulin (0.011; 0.002, 0.019), HOMA-IR (0.012; 0.004, 0.021) and Stumvoll first and second phase (0.008; 0.001, 0.014 and 0.007; 0.001, 0.014). Participants with more MVPA had lower Stumvoll first and second phase (−0.137; −0.210, −0.064 and −0.133; −0.202, −0.063). Concerning changes over time, an increase in ST during gestation was associated with elevated Stumvoll first and second phase (0.006; 0.000, 0.011).

Conclusions

As the glucose-insulin axis is more strongly associated with ST than MVPA in our obese population, pregnant women could be advised to reduce ST in addition to increasing MVPA. Moreover, our findings suggest that behaviour change interventions aiming at GDM risk reduction should start in early or pre-pregnancy.

What Accounts for Physical Activity during Pregnancy? A Study on the Sociodemographic Predictors of Self-Reported and Objectively Assessed Physical Activity during the 1st and 2nd Trimesters of Pregnancy

Physical activity (PA) during pregnancy has positive health implications for both mother and child. However, current literature indicates that not all pregnant women meet the international recommendations for PA (at least 150 min/week of moderate-to-vigorous PA). The main objective of this study was to assess PA levels among pregnant women in the city of Donostia-San Sebastian and identify their main sociodemographic predictors. We recruited 441 women in the 12th week of pregnancy from the local public obstetric health services. Women wore an accelerometer for one week during two separate time points (1st and 2nd trimesters of pregnancy) and completed a questionnaire assessing several sociodemographic variables as well as self-reported PA. With this information, we estimated women’s overall PA levels during both time points. The fulfillment of PA recommendations raised up to 77% and 85% during the first and second trimesters, respectively. We found that a higher number of children and a greater preference for exercise positively predicted light-to-moderate PA, being the most consistent predictors. The availability of a greater number of cars negatively predicted moderate-to-vigorous PA.

Reproductive history, maternal anxiety and past physical activity practice predict physical activity levels throughout pregnancy

We compared physical activity (PA) levels between pregnant women who conceived naturally (NC) or after fertility treatments (FT) and determined factors predicting prenatal moderate-to-vigorous intensity physical activity (MVPA).

The study was conducted in Trois-Rivières (Canada) between October 2015 and July 2018. MVPA and anxiety levels were assessed at each trimester of pregnancy (TR1, TR2 and TR3) using an accelerometer and the State-Trait Anxiety Inventory, respectively. Sociodemographic and reproductive history data were self-reported or collected from medical files. Repeated measures analysis of variance and regression analyses were conducted.

Ninety-six women were included in the analyses (58 NC and 38 FT). MVPA levels and daily step counts decreased significantly throughout pregnancy (time effect: F = 28.68, p < 0.0001 and F = 39.18, p < 0.0001, respectively), but NC and FT women presented similar MVPA and daily step counts (no group effect). The decline in PA practice throughout pregnancy was similar in both groups (no interaction effect). At TR1, State (β = −0.272, p = 0.012) and Trait (β = −0.349, p = 0.001) anxiety and past PA (β = 0.483, p < 0.0001) were correlated with MVPA. Past MVPA was also correlated with MVPA at TR2 (β = 0.595, p < 0.0001) and TR3 (β = 0.654, p < 0.0001). Past PA was the strongest predictors of MVPA levels at TR1, TR2, and TR3, predicting 17% (p = 0.0002), 34% (p < 0.0001) and 42% (p < 0.0001), respectively. Overall, our findings suggest that MVPA practice throughout pregnancy is built on past PA practice. Therefore, to be effective at promoting PA throughout pregnancy, obstetric health care providers and fitness professionals should reinforce the importance of being active as early as possible during pregnancy.

Effects of a lifestyle intervention in routine care on prenatal physical activity - findings from the cluster-randomised GeliS trial

Background

Excessive gestational weight gain (GWG) is associated with an increased risk of pregnancy and obstetric complications. The “healthy living in pregnancy” (GeliS) study was performed in a routine care setting with the aim of limiting excessive GWG. The purpose of this secondary analysis is to evaluate the effect of the intervention on physical activity (PA) behaviour and to assess the impact of PA intensities on GWG.

Methods

The cluster-randomised, multicentre GeliS trial was performed in a routine care setting alongside scheduled prenatal visits. Pregnant women with a pre-pregnancy BMI between 18.5 and 40.0 kg/m² were either assigned to the control group receiving usual care or to the intervention group. Participants in the intervention group attended three antenatal counselling sessions on diet and PA and one additional postpartum session. Data on PA behaviour were collected twice, before the end of the 12th (baseline) and after the 29th week of gestation using the Pregnancy Physical Activity Questionnaire.

Results

PA data were available for 1061 (93%) participants in the intervention and 1040 (93%) in the control group. Women in the intervention group reported significant improvements in the levels of total PA (p < 0.001), total PA of light intensity and above (p < 0.001), moderate-intensity (p = 0.024) and vigorous-intensity activities (p = 0.002) as well as sport activities (p < 0.001) in late pregnancy compared to the control group. The proportion of women meeting the international PA recommendations in late pregnancy was significantly higher in the intervention (64%) versus the control group (49%, p < 0.001). Activities of light-intensity and above (p = 0.006), light-intensity (p = 0.002) and vigorous-intensity (p = 0.014) in late pregnancy were inversely associated with total GWG.

Conclusion

We found significant evidence of improvements in the PA pattern of pregnant women receiving lifestyle counselling within the framework of routine care. Most PA intensities were inversely associated with total GWG which indicates that PA across different intensities should be promoted.

Trial registration

NCT01958307, ClinicalTrials.gov, retrospectively registered 9 October, 2013.

The Association between Neighborhood Environments and Physical Activity from Pregnancy to Postpartum: a Prospective Cohort Study

The objectives of this study were to determine if neighborhood measures were associated with physical activity cross-sectionally during late pregnancy (27-30 weeks' gestation), 3 months postpartum, and 12 months postpartum, and longitudinally with an increase in physical activity from late pregnancy to 12 months postpartum. Data are from the Pregnancy, Infection, and Nutrition (PIN3) and Postpartum Prospective Cohort Study. Dichotomized self-reported recreation and total physical activity hours/week were explored cross-sectionally at three time points, and as an increase over time. Four factors from a neighborhood environmental audit were examined: arterial or thoroughfare, walkable neighborhood, physical incivilities, and decoration. Secondary spatial data included population density, hilliness, intersection density, distance to nearest major road, distance to nearest park, distance to nearest physical activity facility, and distance to nearest bus stop. Multilevel mixed-effects logistic regression models were used to assess the association between environmental variables and physical activity measures. A number of environmental variables were associated with total and recreation physical activity at the three time points in cross-sectional models. For increase in recreation physical activity over time, a moderate distance to nearest major road was significantly associated with increased recreation physical activity from 3 to 12 months postpartum (tertile 2 OR 2.13, 95% CI 1.08, 4.22). Living the furthest distance from the nearest park was inversely associated with an increase in recreation physical activity from pregnancy to 3 months postpartum (tertile 3 OR 0.50, 95% CI 0.29, 0.85). The findings of this study indicate that several aspects of the neighborhood environment, such as walkability, access to transit, distance to recreation facilities, and road networks, are associated with physical activity during different stages of pregnancy and postpartum. Since physical activity may result in long-term health benefits for both the woman and child, environments that support this activity should be encouraged.

Correlates of Prenatal Diet Quality in Low-Income Hispanic Women

BACKGROUND

Low-income Hispanic women are at-risk of poor prenatal diet quality. Correlates associated with prenatal diet quality in this group of women are understudied.

OBJECTIVE

The objective of this study was to examine the associations between financial, cultural, psychosocial, and lifestyle correlates and prenatal diet quality in low-income Hispanic women.

DESIGN

This cross-sectional analysis used data from pregnant women enrolled in the Starting Early Trial, a randomized-controlled trial of a primary-care based child obesity prevention program beginning in pregnancy. The trial enrolled women from clinics affiliated with a large urban medical center in New York City from 2012 to 2014. Financial, cultural, psychosocial, and lifestyle variables were collected using a comprehensive baseline questionnaire. Usual dietary intakes over the past year were assessed using the Block Food Frequency Questionnaire 2005 bilingual version.

PARTICIPANTS

The study enrolled low-income Hispanic women between 28 and 32 gestational weeks (N=519).

MAIN OUTCOME MEASURES

Prenatal diet quality was measured by the Healthy Eating Index 2015.

STATISTICAL ANALYSES PERFORMED

Unadjusted and adjusted multivariable linear regression analyses were performed to determine independent associations between financial, cultural, psychosocial, and lifestyle correlates and Healthy Eating Index 2015 total score.

RESULTS

Overall prenatal diet quality was poor (mean Healthy Eating Index 2015 total score=69.0±9.4). Most women did not meet the maximum score for total vegetables (65.3%), whole grains (97.1%), dairy (74.8%), fatty acids (84.4%), refined grains (79.8%), sodium (97.5%), saturated fats (92.9%), and added sugars (66.5%). Women who reported screen time ≤2 hours/day, physical activity before and/or during pregnancy, and being born outside the United States had higher mean Healthy Eating Index 2015 total score than women with screen time >2 hours/day, no physical activity, and those born in the United States.

CONCLUSIONS

Prenatal diet quality of low-income pregnant Hispanic women was suboptimal. This cross-sectional study revealed associations between cultural and lifestyle factors and prenatal diet quality in low-income Hispanic women. Longitudinal studies are needed to determine long-term influences and specific behaviors to target for effective intervention studies.

Comparison and validation of accelerometer wear time and non-wear time algorithms for assessing physical activity levels in children and adolescents

Background

Accelerometers are widely used to measure sedentary time and daily physical activity (PA). However, data collection and processing criteria, such as non-wear time rules might affect the assessment of total PA and sedentary time and the associations with health variables. The study aimed to investigate whether the choice of different non-wear time definitions would affect the outcomes of PA levels in youth.

Methods

Seventy-seven healthy youngsters (44 boys), aged 10–17 years, wore an accelerometer and kept a non-wear log diary during 4 consecutives days. We compared 7 published algorithms (10, 15, 20, 30, 60 min of continuous zeros, Choi, and Troiano algorithms). Agreements of each algorithm with the log diary method were assessed using Bland-Altmans plots and by calculating the concordance correlation coefficient for repeated measures.

Results

Variations in time spent in sedentary and moderate to vigorous PA (MVPA) were 30 and 3.7%. Compared with the log diary method, greater discrepancies were found for the algorithm 10 min (p < 0.001). For the time assessed in sedentary, the agreement with diary was excellent for the 4 algorithms (Choi, r = 0.79; Troiano, r = 0.81; 30 min, r = 0.79; 60 min, r = 0.81). Concordance for each method was excellent for the assessment of time spent in MVPA (> 0.86). The agreement for the wear time assessment was excellent for 5 algorithms (Choi r = 0.79; Troiano r = 0.79; 20 min r = 0.77; 30 min r = 0.80; 60 min r = 0.80).

Conclusions

The choice of non-wear time rules may considerably affect the sedentary time assessment in youth. Using of appropriate data reduction decision in youth is needed to limit differences in associations between health outcomes and sedentary behaviors and may improve comparability for future studies. Based on our results, we recommend the use of the algorithm of 30 min of continuous zeros for defining non-wear time to improve the accuracy in assessing PA levels in youth.

Trial registration

NCT02844101 (retrospectively registered at July 13th 2016).

Electronic supplementary material

The online version of this article (10.1186/s12874-019-0712-1) contains supplementary material, which is available to authorized users.

Physical Activity Questionnaires for Pregnancy: A Systematic Review of Measurement Properties

Background

In order to assess physical activity (PA) during pregnancy, it is important to choose the instrument with the best measurement properties.

Objectives

To systematically summarize, appraise, and compare the measurement properties of all self-administered questionnaires assessing PA in pregnancy.

Methods

We searched PubMed, Embase, and SPORTDiscus with the following inclusion criteria: (i) the study reported at least one measurement property (reliability, criterion validity, construct validity, responsiveness) of a self-administered questionnaire; (ii) the questionnaire intended to measure PA; (iii) the questionnaire was evaluated in healthy pregnant women; and (iv) the study was published in English. We evaluated results, quality of individual studies, and quality of evidence using a standardized checklist (Quality Assessment of Physical Activity Questionnaires [QAPAQ]) and the GRADE (Grading of Recommendation, Assessment, Development, and Evaluation) approach.

Results

Seventeen articles, reporting 18 studies of 11 different PA questionnaires (17 versions), were included. Most questionnaire versions showed insufficient measurement properties. Only the French and Turkish versions of the Pregnancy Physical Activity Questionnaire (PPAQ) showed both sufficient reliability and construct validity. However, all versions of the PPAQ pooled together showed insufficient construct validity. The quality of individual studies was usually high for reliability but varied considerably for construct validity. Overall, the quality of evidence was very low to moderate.

Conclusions

We recommend the PPAQ to assess PA in pregnancy, although the pooled results revealed insufficient construct validity. The lack of appropriate standards in data collection and processing criteria for objective devices in measuring PA during pregnancy attenuates the quality of evidence. Therefore, research on the validity of comparison instruments in pregnancy followed by consensus on validation reference criteria and standards of PA measurement is needed.

Electronic supplementary material

The online version of this article (10.1007/s40279-018-0961-x) contains supplementary material, which is available to authorized users.

Progressive changes in walking kinematics throughout pregnancy-A follow up study

BACKGROUND

Progressive weight gain and changes in its distribution following pregnancy may be challenging for the gravidas' ability to move in a stable way.

RESEARCH QUESTION

How is gait kinematics changing throughout pregnancy and to what extend is it affected by physical activity level and energy balance?

METHODS

30 women were enrolled. Three experimental sessions were arranged according to the same protocol in the first, second and third trimesters of pregnancy. Walking kinematics at a self-selected speed was registered. The total physical activity (TPA) was assessed from the subjects' questionnaires. Energy balance ('positive', 'balanced' or 'negative') was estimated as the difference between dietary energy intake and energy expenditure during 7 days.

RESULTS

No significant differences were found in the spatiotemporal variables between experimental sessions. However, the gait analysis revealed significant increments in the single support and base of support (BoS) measures. Generally, the sagittal plane mobility of the lower limb joints did not differ, however, the pelvic tilt increased in late pregnancy. The hip and pelvis angles were significantly different over the gait cycle throughout gestation. The 'balanced' energy was dominant in the first trimester although the relative number of participants with negative balance increased over pregnancy. Overall, gait parameters were independent of the energy balance. However, significant correlation was found between gait parameters, such as BoS, velocity, stride length, and TPA in the advanced pregnancy.

SIGNIFICANCE

The longitudinal assessment of walking kinematics demonstrates few changes adopted to accommodate for pregnancy. The enlargement of BoS is considered as a strategy to provide safety and stability. The increased pelvic tilt is likely to compensate for changes in the body mass distribution. The physical activity correlates with the BoS measures and stride length and thus may be important for enhancing gait stability.

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.

Riding the Rhythm of Melatonin Through Pregnancy to Deliver on Time

Pregnancy is influenced by the circadian ("circa" or approximately; diēm or day) system, which coordinates physiology and behavior with predictable daily changes in the environment such as light/dark cycles. For example, most species deliver around a particular time of day. In mammals, circadian rhythms are controlled by the master circadian pacemaker, the suprachiasmatic nucleus. One key way that the suprachiasmatic nucleus coordinates circadian rhythms throughout the body is by regulating production of the sleep-promoting hormone melatonin. Serum melatonin concentration, which peaks at night and is suppressed during the day, is one of the best biological indicators of circadian timing. Circadian misalignment causes maternal disturbances in the temporal organization of many physiological processes including melatonin synthesis, and these disturbances of the circadian system have been linked to an increased risk for pregnancy complications. Here, we review evidence that melatonin helps regulate the maternal and fetal circadian systems and the timing of birth. Finally, we discuss the potential for melatonin-based therapeutic strategies to alleviate poor pregnancy outcomes such as preeclampsia and preterm birth.

Quality of life in Japanese couples during the transition to parenthood

OBJECTIVE

This study aimed to examine the quality of life (QOL) in Japanese couples during the transition to parenthood with their first child.

BACKGROUND

Relevant literature suggests that the health status of women drop during pregnancy and the postpartum period. However, less is known about their partner's well-being during the transition to parenthood and little research has addressed the relationship between couples' QOL across multiple domains.

METHOD

Participants included 9216 married Japanese men and women, including 3729 couples, who were expecting or raising their first child under the age of three. They independently completed questionnaires on baseline demographics and on WHOQOL-BREF.

RESULTS

Men showed higher scores for psychological QOL, while women had higher scores for social and environment QOL. A significant interaction between gender and stage of transition to parenthood was found. The moderating effect of age between the stage and QOL was found for men on the physical and psychological domains. Couples' QOL scores were weakly to moderately correlated.

CONCLUSION

Findings suggest that both men and women had lower QOL, with the exception of women's physical QOL, after childbirth, but they showed different trends during the transition to parenthood across different domains of QOL.

Lumbopelvic pain, anxiety, physical activity and mode of conception: a prospective cohort study of pregnant women

OBJECTIVES

Pregnancy-related lumbopelvic pain (LPP) is a frequent condition known to significantly affect women in their daily life. The aetiology of pregnancy-related LPP pain is still not clearly established but the mode of conception has been suggested to contribute to LPP. Anxiety related to fertility treatments may be one of the contributing factors. The primary objectives of this study were to determine the evolution of LPP prevalence and severity, and anxiety throughout pregnancy in women who conceived spontaneously (SP) or after fertility treatments (FT). A further aim was to examine the relationship between pregnancy-related LPP severity and anxiety. The secondary objective was to determine the evolution of physical activity and their correlation with the severity of pregnancy-related LPP.

DESIGN

Prospective cohort study.

SETTING

Pregnant women were recruited through physicians' referrals, posters and newspaper advertisements in the local and surrounding communities (hospital, maternity care clinic, prenatal centres, sports centres, local university) in the city of Trois-Rivières, Canada.

PARTICIPANTS

59 pregnant women (33 SP and 26 FT) were assessed during the first, second and third trimester of pregnancy.

PRIMARY AND SECONDARY OUTCOME MEASURES

Pregnancy-related LPP prevalence and severity (primary), trait and state anxiety, and physical activity levels (secondary).

RESULTS

There was no relationship between the mode of conception and the outcome measures. The prevalence and severity of LPP increased over the course of pregnancy (time effect, p<0.0001) whereas trait anxiety decreased from early to mid-pregnancy (time effect, p=0.03). Activity limitations increased throughout pregnancy (time effect, p<0.0001) and physical activity levels decreased (time effect, p<0.0001). The severity of LPP was positively correlated with activity limitations (r=0.51 to 0.55) but negatively with physical activity levels (r=-0.39 to -0.41).

CONCLUSIONS

Maternal health-related factors, such as LPP, anxiety and physical activity, are not different in women who conceived spontaneously or after fertility treatments. The more LPP was severe, the more the women were physically limited and inactive.

Perceived Barriers to Exercise in the First Trimester of Pregnancy

Regular physical activity has been shown to improve pregnancy outcomes. We sought to identify barriers to exercise during the first trimester of pregnancy. Five hundred forty-nine pregnant women in their first trimester rated barriers to exercise on a scale of 1 (not a barrier) to 5 (a huge barrier) and recorded physical activity (minutes/week). Women were placed into one of three classifications, nonexercisers (zero exercise), infrequent exercisers (<150 minutes/week), or exercisers (≥150 minutes/week). The greatest barriers (mean) were nausea/fatigue (3.0) and lack of time (2.6). Exercisers reported significantly lower barrier levels. Nausea/fatigue was a greater barrier for nonexercisers compared to exercisers (3.6 vs 2.8, p < .001). Focusing education and interventions on these barriers may help pregnant women achieve healthy exercise levels.

Validation of the Fitbit Zip and Fitbit Flex with pregnant women in free-living conditions

Physical activity (PA) is a part of a healthy pregnancy. To date, no consumer-based activity monitors have been validated with this population. The aim of this study was to validate the Fitbit Zip and Fitbit Flex monitors in free-living conditions with pregnant women using the ActiGraph GT3X as the ?gold standard?. We compared the accuracy of the Fitbit Zip and Fitbit Flex devices in measuring steps, sedentary time and time spent in different activity intensities. Sixteen women in their third trimester of pregnancy wore the ActiGraph GT3X (hip) plus one Fibit Zip (hip) and one Fitbit Flex (wrist) during seven consecutive days. The validity of Fitbit Zip and Fitbit Flex is good, depending on measured parameters. Fitbit Zip is accurate to measure steps whereas Fitbit Flex is precise for MVPA. When choosing between Fitbit Zip and Fitbit Flex monitors, pregnant women should take into account their preferred PA and the parameters they want to measure..

Pregnancy walking cadence does not vary by trimester

BACKGROUND

Pregnancy-related changes in walking speed, gait dynamics, and total physical activity have been reported in past research, but free-living step cadences and their rates of change across pregnancy have not been studied.

RESEARCH QUESTION

The purpose of this study was to describe free-living stepping cadence in pregnant women and examine differences between second and third trimester women. We hypothesized that physical activity walking cadences would be lower later in pregnancy.

METHODS

Fifty pregnant women were recruited for this study and n = 45 was the analytic sample size; 46.7% were in their second trimester (13-25 weeks) while 53.3% were third trimester (≥26 weeks). Participants completed a survey of demographic characteristics and wore an accelerometer on their non-dominant wrist for 7-8 days. These accelerometer data were downloaded in 60-sec epochs, allowing for determination of min-by-min walking cadence, defined as steps/min. Mean steps/day, mean cadence, peak cadence (average cadence over the 30 min of highest cadence in each day), mean time spent in moderate- to vigorous-intensity physical activity (MVPA, time spent with cadence ≥100 steps/min), and mean daily time spent in several cadence ranges were calculated for each participant. Between-trimester differences were determined using independent-samples t-tests.

RESULTS

Average daily steps were 11,060.1 ± 2,955.3; 66.7% of second trimester and 54.2% of third trimester women met daily step recommendations of 10,000 steps/day, but 0.0% of the sample accumulated the recommended 150 min/wk of MVPA. There were no differences by trimester for cadence at any step rates (p > 0.05).

SIGNIFICANCE

Overall, pregnant women accumulated high numbers of steps per day but at low cadences; neither daily steps nor cadence varied from second to third trimester. These data suggest that steps and MVPA recommendations are not equivalent and therefore should not be used interchangeably, especially during pregnancy.

MET-values of standardised activities in relation to body fat: studies in pregnant and non-pregnant women

Background

Physical activity is associated with health in women. Published MET-values (MET: metabolic equivalent of task) may assess physical activity and energy expenditure but tend to be too low for subjects with a high total body fat (TBF) content and therefore inappropriate for many contemporary women. The MET-value for an activity is the energy expenditure of a subject performing this activity divided by his/her resting energy expenditure, often assumed to be 4.2 kJ/kg/h. Relationships between TBF and MET have been little studied although overweight and obesity is common in women. Available data indicate that MET-values decrease during pregnancy but more studies in pregnant contemporary women are needed.

Subjects and methods

Using indirect calorimetry we measured energy expenditure and assessed MET-values in women, 22 non-pregnant (BMI: 18–34) and 22 in gestational week 32 (non-pregnant BMI: 18–32) when resting, sitting, cycling (30 and 60 watts), walking (3.2 and 5.6 km/h) and running (8 km/h). Relationships between TBF and MET-values were investigated and used to predict modified MET-values. The potential of such values to improve calculations of total energy expenditure of women was investigated.

Results

The resting energy expenditure was below 4.2 kJ/kg/h in both groups of women. Women in gestational week 32 had a higher resting energy metabolism (p < 0.001) and 7–15% lower MET-values (p < 0.05) than non-pregnant women. MET-values of all activities were correlated with TBF (p < 0.05) in non-pregnant women and modified MET-values improved estimates of total energy expenditure in such women. In pregnant women, correlations (p ≤ 0.03) between TBF and MET were found for running (8 km/h) and for walking at 5.6 km/h.

Conclusions

Our results are relevant when attempts are made to modify the MET-system in contemporary pregnant and non-pregnant women. MET-values were decreased in gestational week 32, mainly due to an increased resting energy metabolism and studies describing how body composition affects the one MET-value (i.e. the resting energy metabolism in kJ/kg/h) during pregnancy are warranted. Studies of how pregnancy and TBF affect MET-values of high intensity activities are also needed. Corrections based on TBF may have a potential to improve the MET-system in non-pregnant women.

Physical activity and sedentary behavior during pregnancy and postpartum, measured using hip and wrist-worn accelerometers

BACKGROUND

Physical activity in pregnancy and postpartum is beneficial to mothers and infants. To advance knowledge of objective physical activity measurement during these periods, this study compares hip to wrist accelerometer compliance; assesses convergent validity (correlation) between hip- and wrist-worn accelerometry; and assesses change in physical activity from pregnancy to postpartum.

METHODS

We recruited women during pregnancy (n = 100; 2014-2015), asking them to wear hip and wrist accelerometers for 7 days during Trimester 2 (T2), Trimester 3 (T3), and 3-, 6-, 9- and 12-months postpartum. We assessed average wear-time and correlations (axis-specific counts/minute, vector magnitude counts/day and step counts/day) at T2, T3, and postpartum.

RESULTS

Compliance was higher for wrist-worn accelerometers. Hip and wrist accelerometers showed moderate to high correlations (Pearson's r 0.59 to 0.84). Hip-measured sedentary and active time differed little between T2 and T3. Moderate-to-vigorous physical activity decreased at T3 and remained low postpartum. Light physical activity increased and sedentary time decreased throughout the postpartum period.

CONCLUSIONS

Wrist accelerometers may be preferable during pregnancy and appear comparable to hip accelerometers. As physical activity declines during later pregnancy and may not rebound post birth, support for re-engaging in physical activity earlier in the postpartum period may benefit women.

Correlates of accelerometer-assessed physical activity in pregnancy-The 2015 Pelotas (Brazil) Birth Cohort Study

Objective methods to measure physical activity (PA) have become available and widely used given the high degree of precision to evaluate PA. However, few studies have used accelerometers to measure PA during pregnancy, especially in low‐ and middle‐income countries. We assessed overall PA, moderate, vigorous, and moderate‐to‐vigorous physical activity (MVPA) objectively measured among pregnant women and their correlates in a population‐based study. PA was assessed for seven consecutive days using a raw triaxial wrist‐worn accelerometer in women interviewed around 16 and 24 weeks of gestation in the 2015 Pelotas (Brazil) Birth Cohort Study. The average acceleration, which expresses overall PA, was presented in milli‐g (1 mg = 0.001 g), and average time (min/day) spent in MVPA (>100 mg) was also analyzed in 5‐ and 10‐min bouts. Analyses were performed using linear regression. In total, 2317 women were included in the analyses. Overall PA was 27.6 mg. Pregnant women spent on average 14 min/day in MVPA and 0.4 min in vigorous PA. Time spent in MVPA and total PA were inversely associated with years in school and income, and were lower among women receiving advice to not exercise. MVPA was also inversely associated with age, lower among women living with a partner, and higher among non‐white women. The study indicated low levels of PA among pregnant women. The identified correlates may provide a framework to better understand factors influencing PA during pregnancy and thus inform future interventions.

Rhythmic Three-Part Harmony: The Complex Interaction of Maternal, Placental and Fetal Circadian Systems

From the perspective of circadian biology, mammalian pregnancy presents an unusual biological scenario in which an entire circadian system (i.e., that of the fetus) is embodied within another (i.e., that of the mother). Moreover, both systems are likely to be influenced at their interface by a third player, the placenta. Successful pregnancy requires major adaptations in maternal physiology, many of which involve circadian changes that support the high metabolic demands of the growing fetus. A functional role for maternal circadian adaptations is implied by the effects of circadian disruption, which result in pregnancy complications including higher risks for miscarriage, preterm labor, and low birth weight. Various aspects of fetal physiology lead to circadian variation, at least in late gestation, but it remains unclear what drives this rhythmicity. It likely involves contributions from the maternal environment and possibly from the placenta and the developing intrinsic molecular clocks within fetal tissues. The role of the placenta is of particular significance because it serves not only to relay signals about the external environment (via the mother) but may also exhibit its own circadian rhythmicity. This review considers how the fetus may be influenced by dynamic circadian signals from the mother and the placenta during gestation, and how, in the face of these changing influences, a new fetal circadian system emerges. Particular emphasis is placed on the role of endocrine signals, most notably melatonin and glucocorticoids, as mediators of maternal-fetal circadian interactions, and on the expression of the clock gene in the 3 compartments. Further study is required to understand how the mother, placenta, and fetus interact across pregnancy to optimize circadian adaptations that support adequate growth and development of the fetus and its transition to postnatal life in a circadian environment.

Improving pregnancy outcome in obese women: the UK Pregnancies Better Eating and Activity randomised controlled Trial

Background

Obesity in pregnancy is associated with insulin resistance, which underpins many common complications including gestational diabetes mellitus (GDM) and fetal macrosomia.

Objectives

To assess the effect of a complex behavioural intervention based on diet and physical activity (PA) on the risk of GDM and delivery of a large-for-gestational age (LGA) infant.

Design

Three phases: (1) the development phase, (2) the pilot study and (3) a multicentre randomised controlled trial (RCT) comparing a behavioural intervention to improve glycaemic control with standard antenatal care in obese pregnant women. A cost–utility analysis was undertaken to estimate the cost-effectiveness of the health training (intervention) over and above standard care (control).

Setting

Pilot study: antenatal clinics in four inner-city UK hospitals. RCT: eight antenatal clinics in eight UK inner-city hospitals.

Participants

Women were eligible for inclusion if they had a body mass index of ≥ 30 kg/m2, were pregnant with a single fetus and at 15+0to 18+6weeks’ gestation, were able to give written informed consent and were without predefined disorders.

Intervention

The intervention comprised an initial session with a health trainer, followed by eight weekly sessions. Dietary advice recommended foods with a low dietary glycaemic index, avoidance of sugar-sweetened beverages and reduced saturated fats. Women were encouraged to increase daily PA.

Main outcome measures

Development phase: intervention development, acceptability and optimal approach for delivery. Pilot study: change in dietary and PA behaviours at 28 weeks’ gestation. RCT: the primary outcome of the RCT was, for the mother, GDM [as measured by the International Association of the Diabetes and Pregnancy Study Groups (IADPSG)’s diagnostic criteria] and, for the infant, LGA delivery (i.e. customised birthweight ≥ 90th centile for gestational age).

Results

Development phase: following a literature meta-analysis, a study of dietary intention questionnaires and semistructured interviews, an intervention based on behavioural science was developed that incorporated optimal and acceptable methods for delivery. Pilot study: the pilot study demonstrated improvement in dietary behaviours in the intervention compared with the standard care arm but no increase in objectively measured PA. Process evaluation demonstrated feasibility and general acceptability. RCT: the RCT showed no effect of the intervention on GDM in obese pregnant women or the number of deliveries of LGA infants. There was a reduction in dietary glycaemic load (GL) and reduced saturated fat intake, an increase in PA and a modest reduction in gestational weight gain, all secondary outcomes. Lower than expected was the number of LGA infant deliveries in all women, which suggested that universal screening for GDM with IADPSG’s diagnostic criteria, and subsequent treatment, may reduce the number of deliveries of LGA infants. According to the cost–utility analysis, the estimated probability that the UK Pregnancies Better Eating and Activity Trial (UPBEAT) behavioural intervention is cost-effective at the £30,000/quality-adjusted life-year willingness-to-pay threshold was 1%.

Limitations

Included the high refusal rate for participation and self-reported assessment of diet and PA.

Conclusions

The UPBEAT intervention, an intense theoretically based intervention in obese pregnant women, did not reduce the risk of GDM in women or the number of LGA infant deliveries, despite successfully reducing the dietary GL. Based on total cost to the NHS provider and health gains, the UPBEAT intervention provided no supporting evidence to suggest that the intervention represents value for money based on the National Institute for Health and Care Excellence benchmarks for cost-effectiveness.

Future work

Alternative strategies for reducing the risk of GDM in obese pregnant women and the number of LGA infant deliveries should be considered, including development of clinically effective interventions to prevent obesity in women of reproductive age, of clinically effective interventions to reduce weight retention following pregnancy and of risk stratification tools in early pregnancy.

Trial registration

Current Controlled Trials ISRCTN89971375 and UK Clinical Research Network Portfolio 5035.

Funding

This project was funded by the NIHR Programme Grant for Applied Research programme and will be published in full inProgramme Grants for Applied Research, Vol. 5, No. 10. See the NIHR journals library website for further project information. Contributions to funding were also provided by the Chief Scientist Office CZB/4/680, Scottish Government Health Directorates, Edinburgh; Guys and St Thomas’ Charity, Tommy’s Charity (Lucilla Poston, Annette L Briley, Paul T Seed) and the NIHR Biomedical Research Centre at Guy’s and St Thomas’ NHS Foundation Trust and King’s College London, UK and the Academy of Finland, Finland. Keith M Godfrey was supported by the National Institute for Health Research through the NIHR Southampton Biomedical Research Centre. Lucilla Poston and Keith M Godfrey were supported by the European Union’s Seventh Framework Programme (FP7/2007-2013), project EarlyNutrition under grant agreement number 289346.

Physical Activity Patterns in Normal-Weight and Overweight/Obese Pregnant Women

The aims of the present study were to assess the volume of physical activity (PA) throughout pregnancy in normal-weight vs overweight/obese women, and to investigate which factors may predict compliance to PA recommendations in these women throughout gestation. In 236 pregnant women, 177 normal-weight and 59 overweight/obese (median[IQR] BMI 21.2[19.9–22.8] vs 26.5[25.5–29.0] kg/m2, respectively), medical history, anthropometry and clinical data, including glucose tolerance, were recorded. In addition, pre-pregnancy PA was estimated by the Kaiser questionnaire, while total, walking and fitness/sport PA during pregnancy were assessed by the Physical Activity Scale for the Elderly (PASE) modified questionnaire, at 14–16, 24–28 and 30–32 weeks of gestation. PA volume was very low in the first trimester of pregnancy in both groups of women. However, it increased in the second and third trimester in normal-weight, but not in overweight/obese subjects. Higher pre-pregnancy PA was a statistically significant predictor of being physically active (>150 minutes of PA per week) during all trimesters of gestation. In conclusion, physical activity volume is low in pregnant women, especially in overweight/obese subjects. PA volume increases during pregnancy only in normal-weight women. Pre-pregnancy PA is an independent predictor of achieving a PA volume of at least 150 min per week during pregnancy.

The influence of physical activity during pregnancy on maternal, fetal or infant heart rate variability: a systematic review

Background

Physical activity (PA) during pregnancy has been shown to be associated with several positive effects for mother, fetus, and offspring. Heart rate variability (HRV) is a noninvasive and surrogate marker to determine fetal overall health and the development of fetal autonomic nervous system. In addition, it has been shown to be significantly influenced by maternal behavior. However, the influence of maternal PA on HRV has not yet been systematically reviewed. Therefore, the aim of this systematic review was to assess the influence of regular maternal PA on maternal, fetal or infant HRV.

Methods

A systematic literature search following a priori formulated criteria of studies that examined the influence of regular maternal PA (assessed for a minimum period of 6 weeks) on maternal, fetal or infant HRV was performed in the databases Pubmed and SPORTDiscus. Quality of each study was assessed using the standardized Quality Assessment Tool for Quantitative Studies (QATQS).

Results

Nine articles were included into the present systematic review: two intervention studies, one prospective longitudinal study, and six post-hoc analysis of subsets of the longitudinal study. Of these articles four referred to maternal HRV, five to fetal HRV, and one to infant HRV. The overall global rating for the standardized quality assessment of the articles was moderate to weak. The articles regarding the influence of maternal PA on maternal HRV indicated contrary results. Five of five articles regarding the influence of maternal PA on fetal HRV showed increases of fetal HRV on most parameters depending on maternal PA. The article referring to infant HRV (measured one month postnatal) showed an increased HRV.

Conclusions

Based on the current evidence available, our overall conclusion is that the hypothesis that maternal PA influences maternal HRV cannot be supported, but there is a trend that maternal PA might increase fetal and infant HRV (clinical conclusion). Therefore, we recommend that further, high quality studies addressing the influence of maternal PA on HRV should be performed (methodological conclusion).

The London Exercise And Pregnant smokers (LEAP) trial: a randomised controlled trial of physical activity for smoking cessation in pregnancy with an economic evaluation

BACKGROUND

Smoking during pregnancy is the main preventable cause of poor birth outcomes. Improved methods are needed to help women to stop smoking during pregnancy. Pregnancy provides a compelling rationale for physical activity (PA) interventions as cessation medication is contraindicated or ineffective, and an effective PA intervention could be highly cost-effective.

OBJECTIVE

To examine the effectiveness and cost-effectiveness of a PA intervention plus standard behavioural support for smoking cessation relative to behavioural support alone for achieving smoking cessation at the end of pregnancy.

DESIGN

Multicentre, two-group, pragmatic randomised controlled trial and economic evaluation with follow-up at the end of pregnancy and 6 months postnatally. Randomisation was stratified by centre and a computer-generated sequence was used to allocate participants using a 1 : 1 ratio.

SETTING

13 hospitals offering antenatal care in the UK.

PARTICIPANTS

Women between 10 and 24 weeks' gestation smoking five or more cigarettes a day before pregnancy and one or more during pregnancy.

INTERVENTIONS

Participants were randomised to behavioural support for smoking cessation (control) or behavioural support plus a PA intervention consisting of supervised treadmill exercise plus PA consultations. Neither participants nor researchers were blinded to treatment allocation.

MAIN OUTCOME MEASURES

The primary outcome was self-reported, continuous smoking abstinence between a quit date and end of pregnancy, validated by expired carbon monoxide and/or salivary cotinine. Secondary outcomes were maternal weight, depression, birth outcomes, withdrawal symptoms and urges to smoke. The economic evaluation investigated the costs of the PA intervention compared with the control intervention.

RESULTS

In total, 789 women were randomised (n = 394 PA, n = 395 control). Four were excluded post randomisation (two had been enrolled twice in sequential pregnancies and two were ineligible and randomised erroneously). The intention-to-treat analysis comprised 785 participants (n = 392 PA, n = 393 control). There was no significant difference in the rate of abstinence at the end of pregnancy between the PA group (7.7%) and the control group (6.4%) [odds ratio for PA group abstinence 1.21, 95% confidence interval (CI) 0.70 to 2.10]. For the PA group compared with the control group, there was a 33% (95% CI 14% to 56%), 28% (95% CI 7% to 52%) and 36% (95% CI 12% to 65%) significantly greater increase in self-reported minutes of moderate- and vigorous-intensity PA from baseline to 1 week, 4 weeks and 6 weeks respectively. Accelerometer data showed that there was no significant difference in PA levels between the groups. There were no significant differences between the groups for change in maternal weight, depression, withdrawal symptoms or urges to smoke. Adverse events and birth outcomes were similar between the groups except for there being significantly more caesarean births in the control group than in the PA group (28.7% vs. 21.3%; p < 0.023). The PA intervention was less costly than the control intervention by £35 per participant. This was mainly attributable to increased health-care usage in the control group. However, there was considerable statistical uncertainty around this estimate.

CONCLUSIONS

During pregnancy, offering an intervention combining supervised exercise and PA counselling does not add to the effectiveness of behavioural support for smoking cessation. Only 10% of participants had PA levels accessed by accelerometer and it is, therefore, unclear whether or not the lack of an effect on the primary outcome is the result of insufficient increases in PA. Research is needed to identify the smoking populations most suitable for PA interventions and methods for increasing PA adherence.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN48600346.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 19, No. 84. See the NIHR Journals Library website for further project information.

Community level predictors of physical activity among women in the preconception period

Although physical activity is a key behavior targeted during the preconception period given its significant impact on pregnancy/birth outcomes and psychological well-being, few women meet national guidelines. While intrapersonal factors influencing physical activity among this population have been studied, community factors remain unexplored. The objective of this study was to examine community level predictors of physical activity among preconception women. Data from Add Health were limited to women (Wave III; age 18-28; n = 7,596) and excluded respondents who were pregnant, physically disabled, and missing data. The outcome variable was ≥5 instances of moderate-vigorous physical activity (MVPA) in 1 week. Community predictor variables included neighborhood-level structural and social determinants (e.g., socio-demographic composition; landscape diversity; urbanization; access to resources; crime; vehicle availability). Multilevel logistic regression modeling was used to estimate the odds of engaging in ≥5 instances of MVPA. Few women (26 %) reported ≥5 instances of MVPA in 1 week. Adjusted multilevel analysis revealed women in the preconception period were more likely to report high MVPA when living in communities with larger population densities (OR 1.34, 95 % CI 1.02-1.77) and median household income greater than $50,000 (OR 1.33, 95 % CI 1.06-1.66). Additionally, a significant inverse trend was found between high MVPA and proportion of the community without a high school diploma. Findings suggest that neighborhood composition may have an impact on preconception physical activity status. Implications include increased efforts targeting community conditions for facilitating physical activity; ultimately, improving health among women and subsequent offspring.

Intentions Toward Physical Activity and Resting Behavior in Pregnant Women: Using the Theory of Planned Behavior Framework in a Cross-Sectional Study

BACKGROUND

Pregnant women are recommended to 1) perform daily moderate-intensity physical activity and 2) limit the amount of sedentary time. Many women do not meet these recommendations. Reduced physical activity and increased sedentary behavior may result from women actively intending to rest during pregnancy. The Theory of Planned Behavior (TPB) has been used to assess attitudes (e.g., positive/negative beliefs), subjective norms (e.g., perception of others' views), perceived behavioral control (PBC) (e.g., self-efficacy), and intention toward exercising while pregnant but has not been applied to aspects pertaining to resting during pregnancy.

METHODS

Pregnant women (n = 345) completed a cross-sectional questionnaire that included two TPB Questionnaires where the target behaviors were 1) being physically active and 2) resting. Bootstrapped paired t tests, ANOVA, and linear hierarchal regression analyses were performed to identify predictors of intentions and whether intentions toward the two behaviors varied at different stages of pregnancy.

RESULTS

As women progressed in their pregnancy, their attitude, PBC, and intention toward being physically active all significantly declined. A positive attitude, subjective norms, and intention toward resting all significantly increased with the advancing trimester. Self-reported health conditions predicted lower intention for physical activity but not for resting.

DISCUSSION

The significantly inverse relationship between physical activity and resting across time suggests that women feel they should focus on one behavior at the expense of the other. Finding that women generally do not perceive these behaviors as mutually compatible has implications in strategizing as to how to encourage women to be active during pregnancy.

Physical activities during pregnancy and type of delivery in nulliparae

The aim of this study was to investigate changes in physical activity across pregnancy and the relationship between trimester-specific physical activity and unplanned caesarean sections (CSs). A cohort study design was carried out. A cohort of 150 pregnant women was established when they received prenatal care at 29-40 weeks of gestation at a medical centre in northern Taiwan. Participants were asked to recall the amounts of physical activity in which they had engaged in the three trimesters as assessed by the Pregnancy Physical Activity Questionnaire (PPAQ). Overall self-reported physical activity for the cohort decreased by 31% in the first trimester compared to the pre-gravid period, then increased in the second trimester and remained stable until delivery. A repeated measures analysis of variance was used to evaluate the data and revealed significantly more physical activity during the second trimester than in the first and third trimesters (F = 36.471, P = 0.000). In addition, there was a significant difference between normal spontaneous delivery and unplanned CS groups (F = 4.770, P = 0.031). Logistic regression determined that the odds ratio of undergoing a CS increased by 0.644 (95% confidence interval: 0.429-0.968) for women in the third trimester who performed low levels of physical activity. Results support the benefits of physical activity, and professionals are encouraged to provide pregnant women with information on recommendations for physical activity, particularly in terms of reducing unplanned CSs.

Change in level of physical activity during pregnancy in obese women: findings from the UPBEAT pilot trial

BACKGROUND

Maternal obesity is associated with an increased risk of pregnancy complications, including gestational diabetes. Physical activity (PA) might improve glucose metabolism and reduce the incidence of gestational diabetes. The purpose of this study was to explore patterns of PA and factors associated with change in PA in obese pregnant women.

METHODS

PA was assessed objectively by accelerometer at 16 - 18 weeks' (T0), 27 - 28 weeks' (T1) and 35 - 36 weeks' gestation (T2) in 183 obese pregnant women recruited to a pilot randomised trial of a combined diet and PA intervention (the UPBEAT study).

RESULTS

Valid PA data were available for 140 (77%), 76 (42%) and 54 (30%) women at T0, T1 and T2 respectively. Moderate and vigorous physical activity as a proportion of accelerometer wear time declined with gestation from a median of 4.8% at T0 to 3% at T2 (p < 0.05). Total activity as a proportion of accelerometer wear time did not change. Being more active in early pregnancy was associated with a higher level of PA later in pregnancy. The intervention had no effect on PA.

CONCLUSIONS

PA in early pregnancy was the factor most strongly associated with PA at later gestations. Women should be encouraged to participate in PA before becoming pregnant and to maintain their activity levels during pregnancy. There is a need for effective interventions, tailored to the needs of individuals and delivered early in pregnancy to support obese women to be sufficiently active during pregnancy.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN89971375 (Registered 28/11/2008).

Adherence to physical activity guidelines in mid-pregnancy does not reduce sedentary time: an observational study

Background

Physical activity (PA) interventions designed to prevent prenatal complications have focused on increasing moderate PA yielding conflicting results. Minimal attention has focused on the evaluation of sleep, sedentary behavior (SB), light activity or total daily PA during pregnancy. The purpose of this prospective, longitudinal study was to 1) objectively quantify and compare habitual PA and SB during the 2^nd and 3^rd trimester; and 2) evaluate differences in activity patterns for women meeting prenatal PA guidelines versus those that did not.

Methods

Forty-six participants wore 2 PA monitors (SenseWear® Mini and activPAL™) during week 18 and week 35 of pregnancy. We compared differences in sleep duration, postural allocation, daily steps, and PA between the 2^nd and 3^rd trimester and for women who met and did not meet PA guidelines.

Results

During the 2^nd trimester, 30% of the women’s day (24-hours) was total sleep; 52% SB; 13% light; 3% moderate; and 0% vigorous PA. Light (P = 0.05), vigorous (P = 0.02), and moderate-vigorous PA (MET-minutes; P = 0.02), decreased with a trend in increased SB (P = 0.07). Activity of other intensities and sleep duration did not significantly change. Only 39% and 37% of participants slept between 7–9 hours/night at week 18 and 35, respectively. Forty-six percent (n = 21) and 28% (n = 13) of participants met prenatal PA guidelines during the 2^nd and 3^rd trimester, respectively. At week 18, no differences in total sleep, SB, or light PA existed for women who met PA guidelines versus those who did not; total PA was significantly greater for women who met guidelines. At week 35, women that met PA guidelines had significantly less SB (P < 0.005) than women who did not.

Conclusions

This study demonstrates that pregnant women spend the majority of their day in SB. Significant reductions in total activity across pregnancy may be attributed, in part to shifts in light PA and increased SB. Based on the lifestyle of our sample, regardless of meeting PA guidelines in mid-pregnancy, no significant difference exists in time spent in SB, however meeting PA recommendations in late pregnancy may reduce SB. Future interventions should target reducing SB by increasing light and moderate PA beyond volitional exercise.

Improving ambulatory saliva-sampling compliance in pregnant women: a randomized controlled study

Objective

Noncompliance with scheduled ambulatory saliva sampling is common and has been associated with biased cortisol estimates in nonpregnant subjects. This study is the first to investigate in pregnant women strategies to improve ambulatory saliva-sampling compliance, and the association between sampling noncompliance and saliva cortisol estimates.

Methods

We instructed 64 pregnant women to collect eight scheduled saliva samples on two consecutive days each. Objective compliance with scheduled sampling times was assessed with a Medication Event Monitoring System and self-reported compliance with a paper-and-pencil diary. In a randomized controlled study, we estimated whether a disclosure intervention (informing women about objective compliance monitoring) and a reminder intervention (use of acoustical reminders) improved compliance. A mixed model analysis was used to estimate associations between women's objective compliance and their diurnal cortisol profiles, and between deviation from scheduled sampling and the cortisol concentration measured in the related sample.

Results

Self-reported compliance with a saliva-sampling protocol was 91%, and objective compliance was 70%. The disclosure intervention was associated with improved objective compliance (informed: 81%, noninformed: 60%), F(1,60)  = 17.64, p<0.001, but not the reminder intervention (reminders: 68%, without reminders: 72%), F(1,60)  = 0.78, p = 0.379. Furthermore, a woman's increased objective compliance was associated with a higher diurnal cortisol profile, F(2,64) = 8.22, p<0.001. Altered cortisol levels were observed in less objective compliant samples, F(1,705) = 7.38, p = 0.007, with delayed sampling associated with lower cortisol levels.

Conclusions

The results suggest that in pregnant women, objective noncompliance with scheduled ambulatory saliva sampling is common and is associated with biased cortisol estimates. To improve sampling compliance, results suggest informing women about objective compliance monitoring but discourage use of acoustical reminders.

Pre-pregnancy body size dissatisfaction and excessive gestational weight gain

Body size dissatisfaction has been documented as a risk factor for obesity, but little is known about the effect of body size dissatisfaction on excessive gestational weight gain. The objective of the study was to determine the association of pre-pregnancy body size dissatisfaction with excessive gestational weight gain in Iranian pregnant women. This case-control study compared pre-gravid body satisfaction status in 182 women with excessive gestational weight gain and 180 women who gained weight within the guidelines of the Institute of Medicine. All the participants of the study were 35-41 weeks gestational age and received prenatal care in Shahid Akbarabadi Hospital. The women were asked to think back to their pre-pregnant state and report their body size satisfaction status measured by the Body Image Assessment for Obesity (BIA-O). According to this measurement, the women were divided into three categories: dissatisfied women with a thinner body size preference, dissatisfied women with a heavier body size preference and satisfied women. Among women with excessive gestational weight gain, 56.6% preferred a thinner body size, while 53.9% of those with adequate gestational weight gain were satisfied with their pre-gravid body sizes. After adjusting for cofounders, those with a thinner body size preference were more likely to gain weight excessively during pregnancy when compared to satisfied women (OR: 2.17, 95% CI: 1.17-4.02). Our result showed that thinner body size preference was associated with excessive gestational weight gain. Further studies are needed to investigate whether changes in women's feelings about their body sizes will decrease the proportion of women with excessive gestational weight gain.

Physical activity during pregnancy and offspring cardiovascular risk factors: findings from a prospective cohort study

OBJECTIVES

The long-term consequences of maternal physical activity during pregnancy for offspring cardiovascular health are unknown. We examined the association of maternal self-reported physical activity in pregnancy (18 weeks gestation) with offspring cardiovascular risk factors at age 15.

DESIGN

Prospective cohort study.

SETTING

The Avon Longitudinal Study of Parents and Children (ALSPAC).

PARTICIPANTS

4665 maternal-offspring pairs (based on a sample with multiple imputation to deal with missing data) from the ALSPAC, a prospective cohort based in the South West of England with mothers recruited in pregnancy in 1991-1992.

PRIMARY AND SECONDARY OUTCOME MEASURES

Offspring cardiovascular risk factors at age 15; body mass index (BMI), waist circumference, systolic blood pressure, diastolic blood pressure, glucose, insulin, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides.

RESULTS

Greater maternal physical activity was associated with lower BMI, waist circumference, glucose and insulin in unadjusted analyses. The magnitude of associations was generally small with wide CIs, and most associations attenuated towards the null after adjusting for confounders. The strongest evidence of association after adjustment for confounders was for glucose, although the 95% CI for this association includes the null; a one SD greater physical activity during pregnancy was associated with a -0.013 mmol/L difference in offspring glucose levels (equivalent to approximately one-third of a SD; 95% CI -0.027 to 0.001 mmol/L).

CONCLUSIONS

Our results suggest that maternal physical activity in pregnancy, measured at 18 weeks gestation, is unlikely to be an important determinant of later offspring cardiovascular health. There was some suggestion of association with offspring glucose, but given that all other associations (including insulin) were null after adjustment for confounders, this result should be interpreted with caution.

Developing a complex intervention for diet and activity behaviour change in obese pregnant women (the UPBEAT trial); assessment of behavioural change and process evaluation in a pilot randomised controlled trial

BACKGROUND

Complex interventions in obese pregnant women should be theoretically based, feasible and shown to demonstrate anticipated behavioural change prior to inception of large randomised controlled trials (RCTs). The aim was to determine if a) a complex intervention in obese pregnant women leads to anticipated changes in diet and physical activity behaviours, and b) to refine the intervention protocol through process evaluation of intervention fidelity.

METHODS

We undertook a pilot RCT of a complex intervention in obese pregnant women, comparing routine antenatal care with an intervention to reduce dietary glycaemic load and saturated fat intake, and increase physical activity. Subjects included 183 obese pregnant women (mean BMI 36.3 kg/m2).

RESULTS

Compared to women in the control arm, women in the intervention arm had a significant reduction in dietary glycaemic load (33 points, 95% CI -47 to -20), (p < 0.001) and saturated fat intake (-1.6% energy, 95% CI -2.8 to -0. 3) at 28 weeks' gestation. Objectively measured physical activity did not change. Physical discomfort and sustained barriers to physical activity were common at 28 weeks' gestation. Process evaluation identified barriers to recruitment, group attendance and compliance, leading to modification of intervention delivery.

CONCLUSIONS

This pilot trial of a complex intervention in obese pregnant women suggests greater potential for change in dietary intake than for change in physical activity, and through process evaluation illustrates the considerable advantage of performing an exploratory trial of a complex intervention in obese pregnant women before undertaking a large RCT.

TRIAL REGISTRATION

TRIAL REGISTRATION NUMBER

ISRCTN89971375.

Measuring physical activity in pregnancy: a comparison of accelerometry and self-completion questionnaires in overweight and obese women

OBJECTIVES

Increased physical activity in pregnancy may reduce the risk of gestational diabetes and pre-eclampsia, which occur more commonly in overweight and obese women. There is limited assessment of physical activity questionnaires in pregnancy. This study compares self-reported physical activity using two questionnaire methods with objectively recorded physical activity using accelerometry in overweight and obese pregnant women.

STUDY DESIGN

59 women with booking BMI≥25 kg/m(2) completed the Recent Physical Activity Questionnaire (RPAQ) and Australian Women's Activity Survey (AWAS) or recorded at least 3 days of accelerometry at median 12 weeks' gestation. Accelerometer thresholds of 100 counts/min and 1952 counts/min were used to define light and moderate or vigorous physical activity (MVPA) respectively.

RESULTS

48% of women were in their first pregnancy and 41% were obese. Median daily self-reported MVPA was significantly higher for both AWAS (127 min, p<0.001) and RPAQ (81 min, p<0.001) than that recorded by accelerometer (35 min). There was low or moderate correlation between questionnaire and accelerometer estimates of total active time (AWAS ρ=0.36, p=0.008; RPAQ ρ=0.53, p<0.001) but no significant correlation between estimates of time spent in MVPA.

CONCLUSIONS

These self-report questionnaires over-estimated MVPA and showed poor ability to discriminate women on the basis of MVPA. Accelerometry measurement was feasible and acceptable. Objective methods should be used where possible in studies measuring physical activity in pregnancy. Questionnaires remain valuable to define types of activity.