How Many Valid Days Are Necessary to Assess Physical Activity Data From Accelerometry During Pregnancy?

Maternal 24-h movement patterns across pregnancy and postpartum: The LIFE-Moms consortium

Objective

Time spent among the 24-h movement behaviors (physical activity [PA], sleep, sedentary behavior [SB]) in the perinatal period is important for maternal and child health. We described changes to 24-h movement behaviors and behavior guideline attainment during pregnancy and postpartum and identified correlates of behavior changes.

Methods

This secondary data analysis included the standard of care group (n = 439) from the U.S.-based Lifestyle Interventions For Expectant Moms (LIFE-Moms) consortium, including persons with overweight and obesity. Wrist-worn accelerometry was used to measure movement behaviors early (9-15 weeks) and late (35-36 weeks) pregnancy, and ∼ 1-year postpartum. Sleep and moderate-to-vigorous PA (MVPA) were compared to adult and pregnancy-specific guidelines, respectively. SB was classified into quartiles. PA and SB context were quantified using questionnaires. Mixed models were used to examine changes in behaviors and guidelines and identify correlates.

Results

Participants were 31.3 ± 3.5 years, 53.5 % were Black or Hispanic, and 45.1 % had overweight. Sleep duration decreased across time, but participants consistently met the guideline (range: 85.0-93.6 %). SB increased during pregnancy and decreased postpartum, while light PA and MVPA followed the inverse pattern. Participants met slightly fewer guidelines late pregnancy (1.2 ± 0.7 guidelines) but more postpartum (1.7 ± 0.8 guidelines) than early pregnancy (1.4 ± 0.8 guidelines). Black or Hispanic race/ethnicity, higher pregravid body mass index, and non-day work-shift (e.g., night-shift) were identified correlates of lower guideline adherence and varying PA and SB context.

Conclusion

Perinatal interventions should consider strategies to prevent SB increase and sustain MVPA to promote guideline adherence.

Determinants of Physical Activity Among Black Women During Pregnancy

OBJECTIVE

To describe associations among background determinants of physical activity, modifiable theoretical determinants of physical activity, and measures of physical activity during the second and third trimesters of pregnancy among Black women.

DESIGN

Longitudinal cohort.

SETTING

Medical center obstetric clinic.

PARTICIPANTS

Pregnant Black women (n = 40 in second trimester, n = 38 in third trimester) METHODS: We measured background determinants (demographic and pregnancy characteristics, discrimination, and neighborhood walkability) during the second trimester. We measured modifiable theoretical determinants (self-efficacy and social support) and physical activity using self-report and device measures during the second and third trimesters. We used paired t tests to determine differences in the modifiable theoretical determinants from the second trimester to third trimester and used Pearson correlations among background and modifiable determinants and physical activity measures during the second trimester.

RESULTS

Participants' physical activity levels were low during the second and third trimesters (32% and 22% met recommendation, respectively). We found no changes in self-efficacy or social support between trimesters and found no associations between these modifiable determinants and actual physical activity. We found a positive correlation between previous pregnancies and physical activity measured by devices, r(36) = .33, p = .048. Pregnancy-specific stress, r(38) = -.40, p = .013, was negatively correlated, and age, r(38) = .38, p = .017, was positively correlated with self-reported physical activity.

CONCLUSIONS

Low levels of physical activity during pregnancy coupled with the absence of an association with modifiable factors affecting pregnancy physical activity indicate a need to further examine the social, cultural, and environmental determinants of physical activity.

Examining the Effects of Gestational Physical Activity and Hofbauer Cell Polarization on Angiogenic Factors

While gestational physical activity (PA) has demonstrated health benefits for both birthing parent and fetus, the mechanisms still need to be fully understood. Placental macrophages, or Hofbauer cells (HBCs), comprise a heterogenous population containing inflammatory (CD206-) and anti-inflammatory (CD206+) phenotypes. Similar to other tissue-resident macrophages (TRMs), HBCs are potential mediators of angiogenesis due to their secretion of both pro- and anti-angiogenic factors, including FGF2, VEGF, and SPRY2. While PA is associated with an increase in the proportion of VEGF- and FGF2-producing CD206+ macrophages in other tissues, the phenotypes producing FGF2, VEGF, and SPRY2 in the placenta and the associated relationships with gestational PA have not been studied. Using accelerometry, pregnant participants were classified as physically active or inactive in mid- and late-gestation. Term placenta tissue was collected at delivery and used for Western blotting and immunofluorescence to examine the protein expression of FGF2 and SPRY2, and to localize FGF2 in histological samples, respectively. Primary cultures of HBCs were used to examine the phenotypic differences in FGF2, SPRY2, and VEGF production. While no differences in the placental expression of SPRY2, total FGF2, or high-molecular-weight FGF2 were observed based on PA status, active individuals had significantly reduced levels of low-molecular-weight FGF2. Additionally, HBCs of all polarizations produce VEGF, FGF2, and SPRY2, and can form intercellular junctions and multinucleated giant cells. These findings suggest a possible relationship between PA and HBC-driven angiogenesis, providing an avenue for future exploration.

Effectiveness of interventions to increase device-measured physical activity in pregnant women: systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Interventions that provide pregnant women with opportunities to access and participate in physical activity have been shown to be beneficial to their health. Much of this evidence however has been based on self-reported physical activity data, which may be prone to inflated effects due to recall bias and social desirability bias. No previous synthesis of randomised controlled trials has assessed the effectiveness of these interventions using only device measured data, to assess their health benefits more accurately in pregnant women. This systematic review and meta-analysis aimed to address this evidence gap.

DATA SOURCES

Cochrane Central Register of Controlled Trials, Medline, SportDiscus, APA PsycINFO, Embase and Web of Science databases were queried from inception up to December 2, 2021. An updated search of PubMed was conducted on May 16, 2022.

STUDY ELIGIBILITY CRITERIA

Randomised controlled trials that recruited pregnant women, participating in any physical activity intervention (excluding interventions aimed entirely at body conditioning), compared with standard antenatal care (comparators), using device-measured total physical activity as an outcome were eligible for inclusion.

METHODS

3144 titles and abstracts were screened for eligibility, and 18 met the inclusion criteria. Data were analysed using random effect models, (standardised mean difference and mean difference), using data from baseline to last available follow-up (primary end point), and until between 24 to 30 weeks gestation. Gestational weight gain was also assessed at these timepoints in the included trials.

RESULTS

No significant differences between the groups were found for total physical activity at last available follow-up or 24 to 30 weeks gestation (95% CI 0.03 to 0.27, p = 0.10: 95% CI -0.05 to 0.33, p = 0.15) respectively. On average, pregnant women randomised to a physical activity intervention completed 435 and 449 more steps per day than comparators at last available follow-up and at 24 to 30 weeks gestation (95% CI -0.5-870.6, p = 0.05: 95% CI 5.5-892.7, p = 0.05) respectively. Intervention participants also gained 0.69 kg less (95% CI -1.30 to -0.08, p = 0.03) weight than comparators.

CONCLUSION

Based on device-measured data, interventions to promote physical activity during pregnancy have small but important effects on increasing physical activity and managing excessive gestational weight gain.

Physical Activity and Weight Gain Throughout Pregnancy Are Associated With Umbilical Cord Markers

OBJECTIVE

Maternal serum and umbilical cord (UC) lipid and glucose levels are influenced by a variety of maternal factors over the course of pregnancy, including maternal physical activity (PA) levels and gestational weight gain (GWG). However, previous research has not assessed the interaction of these 2 variables. This study investigated mid-gestation (24-28 weeks) and late gestation (34-38 weeks) maternal and UC serum lipid and glucose profiles in relation to maternal PA status and GWG, independently and in combination.

METHODS

This study had a longitudinal design. Pregnant participants (n = 40) were categorized as active or inactive based on the 2019 Canadian Guideline for Physical Activity throughout Pregnancy, and GWG was categorized as insufficient, appropriate, or excessive based on 2009 Institute of Medicine recommendations. Fasting maternal serum was taken in mid- and late gestation, and venous UC serum was taken at birth.

RESULTS

No relationship was found between maternal serum values and PA and/or GWG. Infants born to individuals who were physically active across pregnancy, or who were active in mid-pregnancy and had their activity status drop in late gestation, had lower UC total cholesterol levels than those who were inactive throughout pregnancy (P < 0.0001). Participants who had gained weight appropriately at mid-gestation had significantly lower UC glucose levels than those who gained weight insufficiently (P = 0.040) or excessively (P = 0.021).

CONCLUSION

In our study, PA, and GWG (independently and in combination) may not have affected maternal serum; however, meeting PA recommendations at mid-gestation may provide prophylactic effects on UC serum, potentially providing long-term health benefits to the newborn.

Relationship between physical activity and mental health in women after childbirth: a cross-sectional exploratory study

Background

Physical activity (PA) is recommended for women after childbirth. However, it is unknown whether PA, such as housework and child-rearing, is associated with mental health. This study aimed to measure daily PA in women 2 months postpartum as well as investigate the relationship between daily PA and mental health.

Methods

In this cross-sectional quantitative exploratory study conducted between September 2017 and May 2018, 110 women were approached for participation. Mental health was evaluated using the General Health Questionnaire-28, and PA measurements were performed using accelerometers that the participants wore for 2 days. Welch’s t-test and linear regression analysis were performed to assess the relationship between PA and mental health.

Results

This study included 99 participants. The mean amount of daily activities from housework and child-rearing was 3.21 ± 1.14 metabolic equivalent of tasks (METs)-h/day and that of time spent sitting was at least 7.5 h/12.5 h. PA time spent in light child-rearing and housework activities was significantly longer among multiparous women than among primiparous women (t =  − 3.41). PA time comprising the duration of moderate (3 METs) or more vigorous PA was 73 min/day. No significant relationship between mental health and PA was observed. However, the amount of daily activities tended to increase with an improvement in mental health. The amount of daily activities exceeded 3 METs-h/day regardless of the mental health status.

Conclusions

No significant relationship was found between the amount of daily activities and mental health. The former increased as the latter improved. The amount of daily activities met the standard recommended by the World Health Organization, regardless of the mental health status.

Relationships between Objectively Measured Sedentary Behavior during Pregnancy and Infant Birthweight

Background: Although numerous studies have assessed physical activity during pregnancy and relationships with infant outcomes, such as birthweight, few have evaluated sedentary behavior. Our objective was to evaluate sedentary behavior across pregnancy and relationships with infant birthweight in a sociodemographically diverse sample. Methods: We measured device-assessed sedentary behavior and physical activity over three days at 16–18, 24–26, and 32–34 weeks gestation and infant birthweight from medical records among 71 participants. We used linear regression to assess relationships between sedentary behavior at each evaluation period with birthweight-for-gestational age Z-scores (BW-for-GA). Results: There were no linear relationships between sedentary behavior and BW-for-GA at any evaluation period. We observed a modest curvilinear relationship between sedentary behavior at 16–18 weeks and BW-for-GA (R² = 0.073, p = 0.021). Low and high levels of sedentary behavior predicted lower BW-for-GA. Multivariate models suggested that this relationship was independent of physical activity levels. Conclusions: Considering the high levels of sedentary behavior during pregnancy observed in many studies, even modest associations with birthweight merit further consideration. Relationships might not be evident later in pregnancy or if only linear relationships are considered. More detailed studies could help guide recommendations on sedentary behavior during pregnancy and the development of more comprehensive interventions.