Predicting the risk of Turner syndrome based on ultrasonographic markers in the first trimester of pregnancy

To the Editor:Turner syndrome is the most common sexchromosome abnormality in females with an incidence of 1 per 2500 female live births,and it is associated with either complete or partial loss of one X chromosome.[1]Predicting the risk of Turner syndrome in the first trimester of pregnancy is of critical importance,in order to provide parturient with reproductive choices for affected fetuses at the earliest opportunity.