Intervention group

Pregnant women were informed by the research assistant staff that they were in the intervention group and were sent a pre-program questionnaire by mail. After being collected by return mail, CBT pamphlet were mailed to them. At a date and time arranged by email, the interventionist conducted a CBT session remotely with each participant using the pamphlet and through video call function software. The date and time for the next session was determined at that time or by subsequent email. After the third session, a post-program evaluation questionnaire was mailed to participants and later collected by return mail. A follow-up email was sent 2 weeks after the third session. In this email, the researcher asked the participants to contact her if they were going to give birth; if they did not, the researcher determined the expected delivery date and sent an email. Further follow-up emails were sent at 1 week, 2 weeks, and 3 weeks after the day of delivery. A postpartum questionnaire was mailed out around 1 month after delivery, and completed questionnaires were collected. In addition, during the sessions, interveners worked from private rooms in the laboratory or at home, and data collection was managed in a secure room at the university. In addition, the researcher explained to the intervention group that since the study was in progress, they were prohibited from talking about the program or sharing the contents of the pamphlet.

Session interventions were performed by a midwife at the advanced level.