3.5 The results of subgroup analysis
Among subjects with pregnancy complications, PTB rates were high regardless of whether they exercised or not, and the adjusted OR(95%CI ) for the risk of PTB related to exercise during pregnancy was 0.87 (0.45-1.74), which was not significant. Among subjects without pregnancy complications, exercise during pregnancy was associated with PTB, and the adjusted OR (95%CI ) was 0.72 (0.55-0.95) (Table 3). However, after interaction analysis, no statistically significant interaction terms were found.