Down’s syndrome screening is done on pregnant women to check for genetic disorders such as Down’s syndrome (23 in one) and some hereditary diseases. The normal values for Down’s syndrome screening are not comparable due to the different testing methods used by different hospital laboratories. Generally speaking, Down’s syndrome screening can be divided into high risk, low risk and critical risk, which are generally reported by hospitals. High risk indicates that there is a possibility of the disease occurring, nor is it certain that the disease is going to occur, in terms of the amount of Down’s syndrome screening results