The origin of the problem comes from a case study of a primigravida with a 39-week obstetrical examination suggesting that the lower edge of the placenta was 24 mm from the uterine orifice and the woman wanted to deliver spontaneously. After the operation, the pregnant woman regretted not being able to deliver vaginally. She regretted that she did not go to a high-level hospital and felt that she had received the knife for nothing. Now that the two-child policy is out, I feel extremely regretful. I feel that small places do not have enough medical conditions, doctors are not skilled enough, and hospitals are afraid to take risks. This kind of situation to the big hospital also may not be able to smooth delivery, pregnancy low set placenta fetal head on the cervical compression expansion degree is not enough, somehow increase the fetal resistance out of the birth canal, fetal heart frequent contractions deceleration, according to the specific fetal heart monitoring to interpret. At the same time, the cervical opening is enlarged, but the placenta does not develop with the enlargement of the cervical opening, the phenomenon of abruption at the possible attachment, and in case of heavy bleeding, the pregnant woman becomes anemic, and in severe cases, shock may occur, and the fetus is at increased risk of hypoxia. According to the situation, it was still in the early stages of the first stage of labor. Generally speaking, it takes 11-12 hours on average to enter the second stage of labor, when the uterus is fully opened and 1-2 hours to deliver the fetus. After that time, the risk of fetal distress is greatly increased. The fetal vagus nerve is excited, the intestinal peristalsis is enhanced, the anal sphincter is relaxed, and defecation occurs. Hypoxia, while increasing carbon dioxide stimulation, increased respiratory movements, fetal stool aspiration. It does not seem to be dangerous, but note that the most dangerous thing about hypoxia for the fetus is in the brain cells, which are irreversibly damaged in just a few minutes, enough to make some of the brain cells irreversible, although the brain cell utilization is very low, but the brain cells are not renewable. For families and individuals is a devastating disaster. The end result of raising water has been fetal feces-like, and waiting any longer may damage brain cells and intelligence. Really in case you give birth fast and deliver within minutes, it can be said to be a miracle. The obstetrics department is looking for safety and the safety of mother and baby. In addition, the placenta low value state is mainly due to: fertilized egg trophoblast inflammation delay, after reaching the uterine cavity can not be timely bed, continue to move down, so that the bed surrounded in a lower position; endometrial lesions and injury meconium vascular formation is poor, the placenta blood supply is insufficient, in order to get more nutrients area increased, so that the lower edge of the downward spread; pregnant women over exercise, after the preterm abortion turned normal, etc. caused.