Preterm labor can occur due to many factors. To know what circumstances are more likely to preterm labor, the following, a detailed and comprehensive introduction of the following points. If the pregnant woman’s uterus is deformed, the fetus cannot grow well, which may lead to preterm delivery. Second, cervical injury. If the patient has had multiple deliveries, miscarriages and other surgical experiences, or has a history of preterm delivery, it will cause cervical damage, which may lead to fetal membrane rupture, and then the situation of preterm delivery. If a pregnant woman has a vaginal infection and certain diseases, she is more likely to have a preterm delivery, which is a more dangerous situation. Vaginitis can cause the fetal membranes to break and preterm labor to occur. Pregnant women should not have too much sexual life. For pregnant women, too much exercise will affect the quality of production. And sex is more athletic, more likely to cause premature birth. Too much sex also has a certain damage to the vagina uterus, so sex is also an important factor in causing preterm labor. Five, mood depression. This is also one of the more influential. If the pregnant woman is depressed, more depressed, it may lead to premature birth. In summary, there are a total of the above five possible situations. Patients can defend themselves according to the above to avoid preterm birth.