People often use \”pregnancy in ten months and delivery in one day\” and \”ripe\” to describe childbirth after the pregnancy period. Therefore, some women are unwilling to induce labor at that time and must wait for natural delivery. Among women who give birth naturally, only about 5% give birth on the expected date of delivery, and about 85% give birth within two weeks before and after the expected date of delivery, which is within the normal range. About 10% of pregnant women after 42 weeks of pregnancy