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The Influence of Objectively Measured Physical Activity During Pregnancy on Maternal and Birth Outcomes in Urban Black South African Women.

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Watson, Estelle D 
Brage, Søren 
White, Tom 
Norris, Shane A 


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.



Birth outcomes, Low-to-middle income country, Maternal outcomes, Physical activity, Pregnancy

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Maternal and Child Health Journal

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Medical Research Council (MC_UU_12015/3)
This work is based on the research supported in part by the National Research Foundation of South Africa for the Grant Nos.: 87944 and 98248 ... SAN is supported by the MRC/DFID African Research Leader Scheme (UK) and DST-NRF Centre of Excellence in Human Development at the University of the Witwatersand, Johannesburg, South Africa. SB and KW are supported by a UK Medical Research Council program grant (MC UU 12015/3), and TW is supported by a studentship from MedImmune Ltd. LKM acknowledges funding from the Academy of Medical Sciences-Newton Advanced Fellowship.