Study On Physical Activity And The Effects Of A Community Based Exercise Intervention Among Pregnant Women In Tianjin,China

Objectives:(1)To explore the prevalence and correlates of physical activity in pregnant urban Chinese women in Tianjin.(2)Track the changes of physical activity during pregnancy and analyze the correlation between physical activity and perinantal outcomes.(3)To evaluate the effects of a community based intervention for impoving pregnant women's physical activity.Methods:(1)During 2012.11 and 2013.3,a prospective cross-sectional study involved 1,056 pregnant women in Tianjin,China.Their socio-demographic characteristics were recorded and the Pregnancy Physical Activity Questionnaire was used to assess their physical activity during pregnancy.Epi data database was established and One-way ANOVA and Chi-square test were used to determine whether the women in each of the three trimesters differed in terms of continuous and categorical variables,respectively.Multinomial logistic regression was performed to estimate the odds ratios(ORs)and 95%confidence intervals(CI)of meeting the guideline.(2)During 2012.11-2013.12,152 pregnant women's physical activity and perinatal outcomes were tracked.The correlations between physical activity and perinatal outcomes were analyzed using single factor analysis such as One-way ANOVA,Pearson/Spearman correlation analysis,etc.(3)A quasi-experimental study was used in the study during 2013.3-2014.2.One hundred and forty pregnant women were sampled by purposive sampling and each group had seventy subjects.The study group received the community based intervention for improving physical activity during pregnancy,while the control group received general guidance.The comparison of physical activity and perinatal outcomes between the study group and the control group were analyzed using Chi-square test and Paired Sample T test,etc.Results:(1)Only 117 of the women(11.1%)met the international guideline for physical activity in pregnancy(?150 min moderate exercise per week).The total energy expenditure in the first trimester(23.98 MET-hours/day)was higher than the second and third trimester(20.41 and 20.11 MET-hours/day)(p<0.001).More than half of the energy expenditure came from sedentary activities.Sports/exercise contributed 1.9%to the total energy expenditure across three trimesters.Higher education level(OR,4.11;95%CI,1.59-10.62),habitual exercise before pregnancy(OR,2.14;95%CI,1.39-3.28),and husband's who exercised habitually(OR,2.21;95%CI,1.33-3.67)significantly increased the odds of meeting the guideline(p<0.001),while a low pre-gravid body mass index(OR,0.42;95%CI,0.20-0.87)significantly decreased these odds(p<0.001).(2)Among 152 pregnant women.101 pregnant women(66.4%)had excessive GWG and the mean GWG was 18.79±15.06kg.The rate of excessive GWG,the mean GWG and blood sugar level among pregnant women meeting the international guideline were significantly lower than the women not meeting the guideline(P<0.01).Negative correlations were found between energy expenditure on sports/exercise and GWG as same as blood sugar level(P<0.05).In late stage during pregnancy,birth weight in group meeting the guideline were significantly lower than another group(P<0.05),meanwhile,the total energy expenditure and energy expenditure on sports/exercise were both negatively correlated to GWG,blood sugar level and birth weight(P<0.05).(3)After intervention,the rate of meeting the guideline among the study group was significantly higher than the control group as same as the total expenditure(sendetary activity excluded).The study group had higher energy expenditure on moderate activity,household activity and sports/exercise than the control group.In terms of perinatal outcomes,GWG,the rate of excessive GWG,the sugar level in the study group were all significantly lower than the control group(P<0.01).Conclusions:Urban Chinese women met the guideline less frequently and expended less energy during pregnancy than women in developed countries.Nearly 50%urban pregnant women had excessive GWG.Physical activity,especially sports/exercise could be useful for controlling the blood sugar level and weight control.The physical activity in the late stage was useful for controlling birth weight.The community based intervention during pregnancy could significantly improve regular physical activity and control GWG as same as blood sugar level.Future interventions based on the clinic environment and target family members need further exploration.