The aim of this study was to investigate changes in physical activity across pregnancy and the relationship between trimester-specific physical activity and unplanned caesarean sections (CSs). A cohort study design was carried out. A cohort of 150 pregnant women was established when they received prenatal care at 29-40 weeks of gestation at a medical centre in northern Taiwan. Participants were asked to recall the amounts of physical activity in which they had engaged in the three trimesters as assessed by the Pregnancy Physical Activity Questionnaire (PPAQ). Overall self-reported physical activity for the cohort decreased by 31% in the first trimester compared to the pre-gravid period, then increased in the second trimester and remained stable until delivery. A repeated measures analysis of variance was used to evaluate the data and revealed significantly more physical activity during the second trimester than in the first and third trimesters (F = 36.471, P = 0.000). In addition, there was a significant difference between normal spontaneous delivery and unplanned CS groups (F = 4.770, P = 0.031). Logistic regression determined that the odds ratio of undergoing a CS increased by 0.644 (95% confidence interval: 0.429-0.968) for women in the third trimester who performed low levels of physical activity. Results support the benefits of physical activity, and professionals are encouraged to provide pregnant women with information on recommendations for physical activity, particularly in terms of reducing unplanned CSs.
Keywords: Pregnancy; physical activity; unplanned caesarean section.