How long to wait for placenta II at 40 weeks needs to be judged according to the actual situation, and not simply according to the maturity of the placenta, there are the following situations: 1, placenta II at 40 weeks of pregnancy is normal, there is no placental aging, the fetal nutrition supply and blood supply are relatively adequate, basically will not affect the growth and development of the fetus, if the fetus has been pelvic, may If the fetus is already in the pelvis, it may be produced in the last 1 week or so, but the situation of each fetus is different, and some fetuses are produced later, so it is not possible to make a specific judgment; 2, if the fetus is not yet in the pelvis at this time, it may be relatively late for production, but the specific production time is also impossible to judge, and it needs to be judged according to the actual symptoms, if there are contractions, redness, water breaking and other problems, it may be a sign of imminent If there are contractions, redness, water breakage and other problems, it may be a sign of impending labor.