Typical symptoms of amniotic fluid breaking in the 4th month of pregnancy are more fluid flowing out of the pregnant woman’s vagina, which is uncontrollable, and some pregnant women may experience abdominal pain and so on. From the time of pregnancy until the time of birth, the fetus grows and develops within the amniotic fluid in the pregnant woman’s uterus, so changes in the amniotic fluid will affect the fetus. Normally, the breaking of amniotic fluid occurs in late pregnancy when labor is imminent, but some pregnant women may experience breaking of amniotic fluid as early as 4 months of pregnancy. When amniotic fluid breaks in the 4th month of pregnancy, the pregnant woman can feel a large amount of warm liquid, known as amniotic fluid, flowing out through her vagina, which cannot be stopped after tightening the vagina with force. Amniotic fluid should be clear, colorless and tasteless when it is normal, and when there is an infection, there can be a bad smell, accelerated heart rate of the pregnant woman and the fetus; it can be accompanied by abdominal pain, which is relatively mild and can be hidden, mostly caused by the substances in the amniotic fluid irritating the uterus and leading to uterine contractions. In addition, after more amniotic fluid has flowed out, the pregnant woman will find a significant decrease in the amount of amniotic fluid through ultrasound. After the rupture of membranes in the fourth month of pregnancy, the infection rate of the pregnant woman and the fetus increases, and the fetus may have infections, intrauterine death, malformations, etc. It is generally not recommended to continue to keep the fetus in labor, and labor should be induced.