The results of the bivariate tests of the factors at 20 weeks gestation with the mental health risk in the Edinburgh Postpartum Depression Scale at one month postpartum).

*, **: The participants was divided into two groups, i.e. "At high risk" or "Not at high risk" of postpartum depression using the cut-off score of the Japanese version of the Edinburgh Postpartum Depression Scale (8/9) at 20 weeks' gestation and at 1 month after delivery, respectively. The scores of the "At high risk" group were not lower than 8. The scores of the "Not at high risk" group were not greater than 9. "p value" means the value of the Chi-square test for each variable between the two groups. "Total number" means the number of the participants which were in the analyses.*** indicates statistically significant (p The results of the bivariate tests of the factors at 20 weeks gestation with the mental health risk in the Edinburgh Postpartum Depression Scale at one month postpartum).