The main risk of amniocentesis is fetal loss. Most hospitals currently report a fetal loss rate of approximately 0.5% (including miscarriage, infection, intrauterine death, etc.). The main cause of miscarriage is caused by uterine contractions stimulated by the puncture procedure, which is related to the sensitivity of each individual’s uterus and cannot be completely avoided. Therefore, for the safety of the procedure, any frequent contractions or any infection in the body such as upper respiratory tract infection or urinary tract infection should be treated before the procedure and should not be performed immediately. Body temperature should be taken and laboratory tests should be done before surgery, and bed rest for 1 day and no bathing for 24 hours are required after surgery, all to reduce the risk of infection and miscarriage. The occurrence of fetal loss is basically symptomatic within 24 hours after surgery. After 24 hours, the needle dressing can be removed for normal activities, but sexual life and physical labor should be avoided for 2 weeks. If abdominal pain, fever, vaginal bleeding or vaginal fluid occurs after surgery, go to the hospital immediately. If the puncture can be performed in real time under ultrasound guidance, there is no need to worry about piercing the fetus. However, not all hospitals are able to perform this operation. The results of the amniocentesis will not be available for more than a month after the procedure. The reason why it takes so long is that the fetal cells in the amniotic fluid extracted are very few and need to be cultured to obtain more cells before karyotyping can be performed, and the culture process is lengthy. If there are too few cells in the amniotic fluid for a successful culture, the result will not be obtained and the procedure will need to be repeated. Therefore, the real technical challenges in the process of amniocentesis are the laboratory techniques of cell culture and karyotyping, which is why only a few hospitals are able to perform this technique. Failure to obtain a result in culture is one of the risks that must be taken into account. Some hospitals can now perform fluorescent chromosomal in situ hybridization, which does not require cell culture and is essentially failure-free, with results available in 2 weeks, but only for chromosomes 21, 13 and 18 and sex chromosomes, making it suitable for non-advanced patients at high risk for Down’s syndrome screening.