Non-occupational Physical Activity And The Risk Of Preterm Birth

Abstract

Active participation in physical activity (PA) has been confirmed to help maintain health condition and reduce risks of developing chronic diseases in the general population. Systematic reviews and meta-analysis studies have been conducted to investigate the association between occupational physical activity and the risk of preterm birth (PTB). However, the influence of non-occupational physical activity, such as leisure-time physical activity (LTPA), domestic physical activity (DPA) and commuting physical activity (CPA), on incident preterm birth has not been evaluated separately. PURPOSE: To evaluate the association between non-occupational physical activity and risk of preterm birth. Design Meta-analysis of observational studies. Data source PubMed and EMBASE database was searched through Oct 2015. Eligibility criteria Observational studies published in English language, which reported relative risk (RR) and the corresponding confidence intervals (CIs) of PTB in relation to any non-occupational physical activity during pregnancy. RESULTS: Twenty-six observational studies (18 cohort and 8 case-control studies) were included in this meta-analysis. LTPA studies include 13 cohort studies totaling 167,087 participants and 4 case-control studies totaling 966 cases and 1,685 controls. DPA studies include 7 cohort studies totaling 11,009 participants and 3 case-control studies totaling 391 cases and 651 controls. CPA studies include 5 cohort studies totaling 5,489 participants and 2 case-control studies totaling 2,558 cases and 4,144 controls. For LTPA, comparing the highest to the lowest level of PA, the pooled RR was 0.83 (95% CI=0.74-0.93) for cohort studies and 0.60 (95% CI=0.43-0.84) for case-control studies. But, no evidence of reduced risk of PTB was observed with elevated DPA or CPA during pregnancy. CONCLUSIONS: It was found in this meta-analysis that levels of leisure-time, but not domestic or commuting PA during pregnancy was inversely and significantly associated with risk of PTB. Further research is needed to confirm our findings and to determine the optimal intensity and duration of LTPA for pregnant women considering risk of PTB. Supported by the Graduate Abroad Visiting Program from Shanghai University of Sport, China (STFX20150103).