It is normal for a pregnant woman to go into labor in 1-3 days after the oxytocic injection. However, some pregnant women are not sensitive to the oxytocin injection and may take longer. Oxytocin advances the progress of labor mainly by promoting the contraction of the smooth muscles of the uterus. Usually, after the application of oxytocin, more sensitive pregnant women will have contractions after a few minutes, and regular contractions occur when the duration of contractions remains at 40-60 seconds and the interval between contractions is 2-3 minutes. It takes about 11-12 hours for first-time mothers and 6-8 hours for menstruating mothers to fully open the uterus, and about 2 hours to deliver the baby after the uterus is fully opened. However, some pregnant women are not sensitive to the oxytocic injection and the time required for the whole process is extended accordingly. In addition, since some pregnant women may experience nausea, vomiting and diarrhea after using oxytocin, they are advised to strictly follow the medical advice to avoid adverse consequences.