Physical activity trajectory during pregnancy and associations with maternal fatigue using a growth mixture modeling approach.

The purpose of this study was to investigate the associations of physical activity trajectories with maternal fatigue. Pregnant women provided objectively assessed physical activity data by Pregnancy Physical Activity Questionnaire four times. Fatigue scale-14 was used to assess fatigue during pregnancy. Growth mixture modelling characterized physical activity trajectories across pregnancy. The generalized estimating equations was used to analyze the relationship between different physical activity profiles and fatigue in pregnant women. A total of 626 pregnant women were included in analysis in a teaching hospital in Nantong city. Fatigue (total, mental and physical) was not different between two groups based on total energy expenditure of PA (constantly high vs. constantly low). The pregnant women in "constantly high household PA" group had the higher fatigue compared to "constantly low household PA" (P < 0.05) and "constantly medium household PA" (P < 0.05). The pregnant women in "constantly high sport PA" group had lower fatigue compared to "constantly low sport PA" (P < 0.05). Household PA and sport PA were still an independent influencing factor for fatigue after controlling for confounding variables. Specifically, we observed that higher household PA and lower sport PA were associated with higher fatigue during pregnancy.