Fetal arrest refers to the cessation of fetal development. Fetal arrest in the sixth month of pregnancy is related to embryonic factors, maternal factors, environmental factors or other factors. 1. Embryonic factors: when the embryo 13, 6, 18, 21 chromosomes and trisomy 22 are abnormal, it is easy to cause the embryo to stop developing. 2. Maternal factors: such as maternal infection, poor immune status, uterine development abnormalities or malformations, luteal insufficiency, thyroid function abnormalities and smoking, drinking, etc., easy to cause fetal arrest. 3. Environmental factors: mainly related to exposure to radiation, chemicals, heavy metals and air pollution during pregnancy. In addition to the above factors, older gestational age, multiple pregnancies, previous history of fetal termination, etc. can induce fetal termination. When it is clear that the fetus has been sterilized, the pregnant woman should cooperate with the doctor to terminate the pregnancy through medication abortion, curettage and other means. For those who still want to have children, they should actively do chromosome testing and pay attention to adjusting their mindset in daily life. If you have any other questions, it is recommended to consult a professional doctor for guidance.