The procedure of induction of labor is an operation to terminate the pregnancy by inducing contraction of the uterus through artificial means for maternal or fetal reasons. 4 months induction of labor generally has two methods: water bag induction of labor and drug induction of labor. 1. Pre-operative preparation: ultrasound should be done before the operation to observe the placenta, to rule out low position, placenta abruptio, inflammatory or neoplastic diseases of the cervix; 2. A sterile gauze is placed in the posterior fornix to avoid infection due to direct contact of the bladder with the vagina. Insert the water bladder and inject a certain amount of sterile saline into the bladder. After the injection, fold and tie the end of the catheter, wrap it with sterile gauze and insert it into the vagina; 3. Postoperative precautions: After the operation, attention should be paid to measuring the height of the uterine fundus to clarify whether there are signs of placental abruption and internal bleeding. Second, the amniotic cavity drug injection to induce labor: 1, preoperative preparation: before the induction of labor pregnant women pay attention to emptying the bladder, supine on the operating table, abdominal examination, to find out the height of the fundus, the skin disinfection of the injection site; 2, the surgical process: in the fundus and the pubic symphysis between the midline next to the 2 transverse fingers, the fetal limb side of the puncture, amniotic fluid extraction after the slow injection of the drug into the amniotic cavity; 3, postoperative precautions: after surgery Quickly withdraw the needle, press with sterile gauze for 2-3 minutes, and fix with adhesive tape after pressing. Usually contractions occur within 48-72 hours after the injection of drugs to expel the fetus from the body. Induction of labor can cause a certain degree of damage to a woman’s body, so it is recommended not to do it without special circumstances. In addition, it is important to go to a regular hospital for induction of labor and to have adequate examination before induction of labor, to be psychologically prepared and relaxed, not to have sex for 1 month after the operation, and to pay attention to pubic hygiene.