Under normal circumstances, the fetal lungs mature after 37 weeks, so pregnant women usually deliver at 37~41 weeks, which is categorized into preterm, full-term and expired births according to the time period. 1. Labor usually occurs during 28~36 weeks (196~258 days) from the first day of the last menstrual period and is considered preterm. Preterm labor may lead to complications in preterm babies and should be treated aggressively. 2. Delivery between 37 and 41 weeks (259 and 293 days) is considered a full-term labor, which is also normal. 3. Delivery after more than 42 weeks (more than 294 days) is a term birth. If you are not in labor one week after the due date, you need to go to the hospital in time under the guidance of the doctor to actively induce labor. It should be reminded that pregnant women are a special period in a woman’s life, during which she should do the maternity checkup on time, keep a good attitude, relax, eat a reasonable diet and avoid stimulating foods.